diff options
Diffstat (limited to 'reftable')
54 files changed, 11187 insertions, 0 deletions
diff --git a/reftable/LICENSE b/reftable/LICENSE new file mode 100644 index 0000000000..402e0f9356 --- /dev/null +++ b/reftable/LICENSE @@ -0,0 +1,31 @@ +BSD License + +Copyright (c) 2020, Google LLC +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + +* Redistributions of source code must retain the above copyright notice, +this list of conditions and the following disclaimer. + +* Redistributions in binary form must reproduce the above copyright +notice, this list of conditions and the following disclaimer in the +documentation and/or other materials provided with the distribution. + +* Neither the name of Google LLC nor the names of its contributors may +be used to endorse or promote products derived from this software +without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/reftable/basics.c b/reftable/basics.c new file mode 100644 index 0000000000..f761e48028 --- /dev/null +++ b/reftable/basics.c @@ -0,0 +1,128 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "basics.h" + +void put_be24(uint8_t *out, uint32_t i) +{ + out[0] = (uint8_t)((i >> 16) & 0xff); + out[1] = (uint8_t)((i >> 8) & 0xff); + out[2] = (uint8_t)(i & 0xff); +} + +uint32_t get_be24(uint8_t *in) +{ + return (uint32_t)(in[0]) << 16 | (uint32_t)(in[1]) << 8 | + (uint32_t)(in[2]); +} + +void put_be16(uint8_t *out, uint16_t i) +{ + out[0] = (uint8_t)((i >> 8) & 0xff); + out[1] = (uint8_t)(i & 0xff); +} + +int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args) +{ + size_t lo = 0; + size_t hi = sz; + + /* Invariants: + * + * (hi == sz) || f(hi) == true + * (lo == 0 && f(0) == true) || fi(lo) == false + */ + while (hi - lo > 1) { + size_t mid = lo + (hi - lo) / 2; + + if (f(mid, args)) + hi = mid; + else + lo = mid; + } + + if (lo) + return hi; + + return f(0, args) ? 0 : 1; +} + +void free_names(char **a) +{ + char **p; + if (!a) { + return; + } + for (p = a; *p; p++) { + reftable_free(*p); + } + reftable_free(a); +} + +int names_length(char **names) +{ + char **p = names; + for (; *p; p++) { + /* empty */ + } + return p - names; +} + +void parse_names(char *buf, int size, char ***namesp) +{ + char **names = NULL; + size_t names_cap = 0; + size_t names_len = 0; + + char *p = buf; + char *end = buf + size; + while (p < end) { + char *next = strchr(p, '\n'); + if (next && next < end) { + *next = 0; + } else { + next = end; + } + if (p < next) { + if (names_len == names_cap) { + names_cap = 2 * names_cap + 1; + names = reftable_realloc( + names, names_cap * sizeof(*names)); + } + names[names_len++] = xstrdup(p); + } + p = next + 1; + } + + names = reftable_realloc(names, (names_len + 1) * sizeof(*names)); + names[names_len] = NULL; + *namesp = names; +} + +int names_equal(char **a, char **b) +{ + int i = 0; + for (; a[i] && b[i]; i++) { + if (strcmp(a[i], b[i])) { + return 0; + } + } + + return a[i] == b[i]; +} + +int common_prefix_size(struct strbuf *a, struct strbuf *b) +{ + int p = 0; + for (; p < a->len && p < b->len; p++) { + if (a->buf[p] != b->buf[p]) + break; + } + + return p; +} diff --git a/reftable/basics.h b/reftable/basics.h new file mode 100644 index 0000000000..096b36862b --- /dev/null +++ b/reftable/basics.h @@ -0,0 +1,60 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef BASICS_H +#define BASICS_H + +/* + * miscellaneous utilities that are not provided by Git. + */ + +#include "system.h" + +/* Bigendian en/decoding of integers */ + +void put_be24(uint8_t *out, uint32_t i); +uint32_t get_be24(uint8_t *in); +void put_be16(uint8_t *out, uint16_t i); + +/* + * find smallest index i in [0, sz) at which f(i) is true, assuming + * that f is ascending. Return sz if f(i) is false for all indices. + * + * Contrary to bsearch(3), this returns something useful if the argument is not + * found. + */ +int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args); + +/* + * Frees a NULL terminated array of malloced strings. The array itself is also + * freed. + */ +void free_names(char **a); + +/* parse a newline separated list of names. `size` is the length of the buffer, + * without terminating '\0'. Empty names are discarded. */ +void parse_names(char *buf, int size, char ***namesp); + +/* compares two NULL-terminated arrays of strings. */ +int names_equal(char **a, char **b); + +/* returns the array size of a NULL-terminated array of strings. */ +int names_length(char **names); + +/* Allocation routines; they invoke the functions set through + * reftable_set_alloc() */ +void *reftable_malloc(size_t sz); +void *reftable_realloc(void *p, size_t sz); +void reftable_free(void *p); +void *reftable_calloc(size_t sz); + +/* Find the longest shared prefix size of `a` and `b` */ +struct strbuf; +int common_prefix_size(struct strbuf *a, struct strbuf *b); + +#endif diff --git a/reftable/basics_test.c b/reftable/basics_test.c new file mode 100644 index 0000000000..1fcd229725 --- /dev/null +++ b/reftable/basics_test.c @@ -0,0 +1,98 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" + +#include "basics.h" +#include "test_framework.h" +#include "reftable-tests.h" + +struct binsearch_args { + int key; + int *arr; +}; + +static int binsearch_func(size_t i, void *void_args) +{ + struct binsearch_args *args = void_args; + + return args->key < args->arr[i]; +} + +static void test_binsearch(void) +{ + int arr[] = { 2, 4, 6, 8, 10 }; + size_t sz = ARRAY_SIZE(arr); + struct binsearch_args args = { + .arr = arr, + }; + + int i = 0; + for (i = 1; i < 11; i++) { + int res; + args.key = i; + res = binsearch(sz, &binsearch_func, &args); + + if (res < sz) { + EXPECT(args.key < arr[res]); + if (res > 0) { + EXPECT(args.key >= arr[res - 1]); + } + } else { + EXPECT(args.key == 10 || args.key == 11); + } + } +} + +static void test_names_length(void) +{ + char *a[] = { "a", "b", NULL }; + EXPECT(names_length(a) == 2); +} + +static void test_parse_names_normal(void) +{ + char in[] = "a\nb\n"; + char **out = NULL; + parse_names(in, strlen(in), &out); + EXPECT(!strcmp(out[0], "a")); + EXPECT(!strcmp(out[1], "b")); + EXPECT(!out[2]); + free_names(out); +} + +static void test_parse_names_drop_empty(void) +{ + char in[] = "a\n\n"; + char **out = NULL; + parse_names(in, strlen(in), &out); + EXPECT(!strcmp(out[0], "a")); + EXPECT(!out[1]); + free_names(out); +} + +static void test_common_prefix(void) +{ + struct strbuf s1 = STRBUF_INIT; + struct strbuf s2 = STRBUF_INIT; + strbuf_addstr(&s1, "abcdef"); + strbuf_addstr(&s2, "abc"); + EXPECT(common_prefix_size(&s1, &s2) == 3); + strbuf_release(&s1); + strbuf_release(&s2); +} + +int basics_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_common_prefix); + RUN_TEST(test_parse_names_normal); + RUN_TEST(test_parse_names_drop_empty); + RUN_TEST(test_binsearch); + RUN_TEST(test_names_length); + return 0; +} diff --git a/reftable/block.c b/reftable/block.c new file mode 100644 index 0000000000..34d4d07369 --- /dev/null +++ b/reftable/block.c @@ -0,0 +1,452 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "block.h" + +#include "blocksource.h" +#include "constants.h" +#include "record.h" +#include "reftable-error.h" +#include "system.h" +#include <zlib.h> + +int header_size(int version) +{ + switch (version) { + case 1: + return 24; + case 2: + return 28; + } + abort(); +} + +int footer_size(int version) +{ + switch (version) { + case 1: + return 68; + case 2: + return 72; + } + abort(); +} + +static int block_writer_register_restart(struct block_writer *w, int n, + int is_restart, struct strbuf *key) +{ + int rlen = w->restart_len; + if (rlen >= MAX_RESTARTS) { + is_restart = 0; + } + + if (is_restart) { + rlen++; + } + if (2 + 3 * rlen + n > w->block_size - w->next) + return -1; + if (is_restart) { + if (w->restart_len == w->restart_cap) { + w->restart_cap = w->restart_cap * 2 + 1; + w->restarts = reftable_realloc( + w->restarts, sizeof(uint32_t) * w->restart_cap); + } + + w->restarts[w->restart_len++] = w->next; + } + + w->next += n; + + strbuf_reset(&w->last_key); + strbuf_addbuf(&w->last_key, key); + w->entries++; + return 0; +} + +void block_writer_init(struct block_writer *bw, uint8_t typ, uint8_t *buf, + uint32_t block_size, uint32_t header_off, int hash_size) +{ + bw->buf = buf; + bw->hash_size = hash_size; + bw->block_size = block_size; + bw->header_off = header_off; + bw->buf[header_off] = typ; + bw->next = header_off + 4; + bw->restart_interval = 16; + bw->entries = 0; + bw->restart_len = 0; + bw->last_key.len = 0; +} + +uint8_t block_writer_type(struct block_writer *bw) +{ + return bw->buf[bw->header_off]; +} + +/* Adds the reftable_record to the block. Returns -1 if it does not fit, 0 on + success. Returns REFTABLE_API_ERROR if attempting to write a record with + empty key. */ +int block_writer_add(struct block_writer *w, struct reftable_record *rec) +{ + struct strbuf empty = STRBUF_INIT; + struct strbuf last = + w->entries % w->restart_interval == 0 ? empty : w->last_key; + struct string_view out = { + .buf = w->buf + w->next, + .len = w->block_size - w->next, + }; + + struct string_view start = out; + + int is_restart = 0; + struct strbuf key = STRBUF_INIT; + int n = 0; + int err = -1; + + reftable_record_key(rec, &key); + if (!key.len) { + err = REFTABLE_API_ERROR; + goto done; + } + + n = reftable_encode_key(&is_restart, out, last, key, + reftable_record_val_type(rec)); + if (n < 0) + goto done; + string_view_consume(&out, n); + + n = reftable_record_encode(rec, out, w->hash_size); + if (n < 0) + goto done; + string_view_consume(&out, n); + + err = block_writer_register_restart(w, start.len - out.len, is_restart, + &key); +done: + strbuf_release(&key); + return err; +} + +int block_writer_finish(struct block_writer *w) +{ + int i; + for (i = 0; i < w->restart_len; i++) { + put_be24(w->buf + w->next, w->restarts[i]); + w->next += 3; + } + + put_be16(w->buf + w->next, w->restart_len); + w->next += 2; + put_be24(w->buf + 1 + w->header_off, w->next); + + if (block_writer_type(w) == BLOCK_TYPE_LOG) { + int block_header_skip = 4 + w->header_off; + uLongf src_len = w->next - block_header_skip; + uLongf dest_cap = src_len * 1.001 + 12; + + uint8_t *compressed = reftable_malloc(dest_cap); + while (1) { + uLongf out_dest_len = dest_cap; + int zresult = compress2(compressed, &out_dest_len, + w->buf + block_header_skip, + src_len, 9); + if (zresult == Z_BUF_ERROR && dest_cap < LONG_MAX) { + dest_cap *= 2; + compressed = + reftable_realloc(compressed, dest_cap); + if (compressed) + continue; + } + + if (Z_OK != zresult) { + reftable_free(compressed); + return REFTABLE_ZLIB_ERROR; + } + + memcpy(w->buf + block_header_skip, compressed, + out_dest_len); + w->next = out_dest_len + block_header_skip; + reftable_free(compressed); + break; + } + } + return w->next; +} + +uint8_t block_reader_type(struct block_reader *r) +{ + return r->block.data[r->header_off]; +} + +int block_reader_init(struct block_reader *br, struct reftable_block *block, + uint32_t header_off, uint32_t table_block_size, + int hash_size) +{ + uint32_t full_block_size = table_block_size; + uint8_t typ = block->data[header_off]; + uint32_t sz = get_be24(block->data + header_off + 1); + int err = 0; + uint16_t restart_count = 0; + uint32_t restart_start = 0; + uint8_t *restart_bytes = NULL; + uint8_t *uncompressed = NULL; + + if (!reftable_is_block_type(typ)) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + if (typ == BLOCK_TYPE_LOG) { + int block_header_skip = 4 + header_off; + uLongf dst_len = sz - block_header_skip; /* total size of dest + buffer. */ + uLongf src_len = block->len - block_header_skip; + /* Log blocks specify the *uncompressed* size in their header. + */ + uncompressed = reftable_malloc(sz); + + /* Copy over the block header verbatim. It's not compressed. */ + memcpy(uncompressed, block->data, block_header_skip); + + /* Uncompress */ + if (Z_OK != + uncompress2(uncompressed + block_header_skip, &dst_len, + block->data + block_header_skip, &src_len)) { + err = REFTABLE_ZLIB_ERROR; + goto done; + } + + if (dst_len + block_header_skip != sz) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + /* We're done with the input data. */ + reftable_block_done(block); + block->data = uncompressed; + uncompressed = NULL; + block->len = sz; + block->source = malloc_block_source(); + full_block_size = src_len + block_header_skip; + } else if (full_block_size == 0) { + full_block_size = sz; + } else if (sz < full_block_size && sz < block->len && + block->data[sz] != 0) { + /* If the block is smaller than the full block size, it is + padded (data followed by '\0') or the next block is + unaligned. */ + full_block_size = sz; + } + + restart_count = get_be16(block->data + sz - 2); + restart_start = sz - 2 - 3 * restart_count; + restart_bytes = block->data + restart_start; + + /* transfer ownership. */ + br->block = *block; + block->data = NULL; + block->len = 0; + + br->hash_size = hash_size; + br->block_len = restart_start; + br->full_block_size = full_block_size; + br->header_off = header_off; + br->restart_count = restart_count; + br->restart_bytes = restart_bytes; + +done: + reftable_free(uncompressed); + return err; +} + +static uint32_t block_reader_restart_offset(struct block_reader *br, int i) +{ + return get_be24(br->restart_bytes + 3 * i); +} + +void block_reader_start(struct block_reader *br, struct block_iter *it) +{ + it->br = br; + strbuf_reset(&it->last_key); + it->next_off = br->header_off + 4; +} + +struct restart_find_args { + int error; + struct strbuf key; + struct block_reader *r; +}; + +static int restart_key_less(size_t idx, void *args) +{ + struct restart_find_args *a = args; + uint32_t off = block_reader_restart_offset(a->r, idx); + struct string_view in = { + .buf = a->r->block.data + off, + .len = a->r->block_len - off, + }; + + /* the restart key is verbatim in the block, so this could avoid the + alloc for decoding the key */ + struct strbuf rkey = STRBUF_INIT; + struct strbuf last_key = STRBUF_INIT; + uint8_t unused_extra; + int n = reftable_decode_key(&rkey, &unused_extra, last_key, in); + int result; + if (n < 0) { + a->error = 1; + return -1; + } + + result = strbuf_cmp(&a->key, &rkey); + strbuf_release(&rkey); + return result; +} + +void block_iter_copy_from(struct block_iter *dest, struct block_iter *src) +{ + dest->br = src->br; + dest->next_off = src->next_off; + strbuf_reset(&dest->last_key); + strbuf_addbuf(&dest->last_key, &src->last_key); +} + +int block_iter_next(struct block_iter *it, struct reftable_record *rec) +{ + struct string_view in = { + .buf = it->br->block.data + it->next_off, + .len = it->br->block_len - it->next_off, + }; + struct string_view start = in; + struct strbuf key = STRBUF_INIT; + uint8_t extra = 0; + int n = 0; + + if (it->next_off >= it->br->block_len) + return 1; + + n = reftable_decode_key(&key, &extra, it->last_key, in); + if (n < 0) + return -1; + + if (!key.len) + return REFTABLE_FORMAT_ERROR; + + string_view_consume(&in, n); + n = reftable_record_decode(rec, key, extra, in, it->br->hash_size); + if (n < 0) + return -1; + string_view_consume(&in, n); + + strbuf_reset(&it->last_key); + strbuf_addbuf(&it->last_key, &key); + it->next_off += start.len - in.len; + strbuf_release(&key); + return 0; +} + +int block_reader_first_key(struct block_reader *br, struct strbuf *key) +{ + struct strbuf empty = STRBUF_INIT; + int off = br->header_off + 4; + struct string_view in = { + .buf = br->block.data + off, + .len = br->block_len - off, + }; + + uint8_t extra = 0; + int n = reftable_decode_key(key, &extra, empty, in); + if (n < 0) + return n; + if (!key->len) + return REFTABLE_FORMAT_ERROR; + + return 0; +} + +int block_iter_seek(struct block_iter *it, struct strbuf *want) +{ + return block_reader_seek(it->br, it, want); +} + +void block_iter_close(struct block_iter *it) +{ + strbuf_release(&it->last_key); +} + +int block_reader_seek(struct block_reader *br, struct block_iter *it, + struct strbuf *want) +{ + struct restart_find_args args = { + .key = *want, + .r = br, + }; + struct reftable_record rec = reftable_new_record(block_reader_type(br)); + struct strbuf key = STRBUF_INIT; + int err = 0; + struct block_iter next = { + .last_key = STRBUF_INIT, + }; + + int i = binsearch(br->restart_count, &restart_key_less, &args); + if (args.error) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + it->br = br; + if (i > 0) { + i--; + it->next_off = block_reader_restart_offset(br, i); + } else { + it->next_off = br->header_off + 4; + } + + /* We're looking for the last entry less/equal than the wanted key, so + we have to go one entry too far and then back up. + */ + while (1) { + block_iter_copy_from(&next, it); + err = block_iter_next(&next, &rec); + if (err < 0) + goto done; + + reftable_record_key(&rec, &key); + if (err > 0 || strbuf_cmp(&key, want) >= 0) { + err = 0; + goto done; + } + + block_iter_copy_from(it, &next); + } + +done: + strbuf_release(&key); + strbuf_release(&next.last_key); + reftable_record_release(&rec); + + return err; +} + +void block_writer_release(struct block_writer *bw) +{ + FREE_AND_NULL(bw->restarts); + strbuf_release(&bw->last_key); + /* the block is not owned. */ +} + +void reftable_block_done(struct reftable_block *blockp) +{ + struct reftable_block_source source = blockp->source; + if (blockp && source.ops) + source.ops->return_block(source.arg, blockp); + blockp->data = NULL; + blockp->len = 0; + blockp->source.ops = NULL; + blockp->source.arg = NULL; +} diff --git a/reftable/block.h b/reftable/block.h new file mode 100644 index 0000000000..87c77539b5 --- /dev/null +++ b/reftable/block.h @@ -0,0 +1,127 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef BLOCK_H +#define BLOCK_H + +#include "basics.h" +#include "record.h" +#include "reftable-blocksource.h" + +/* + * Writes reftable blocks. The block_writer is reused across blocks to minimize + * allocation overhead. + */ +struct block_writer { + uint8_t *buf; + uint32_t block_size; + + /* Offset of the global header. Nonzero in the first block only. */ + uint32_t header_off; + + /* How often to restart keys. */ + int restart_interval; + int hash_size; + + /* Offset of next uint8_t to write. */ + uint32_t next; + uint32_t *restarts; + uint32_t restart_len; + uint32_t restart_cap; + + struct strbuf last_key; + int entries; +}; + +/* + * initializes the blockwriter to write `typ` entries, using `buf` as temporary + * storage. `buf` is not owned by the block_writer. */ +void block_writer_init(struct block_writer *bw, uint8_t typ, uint8_t *buf, + uint32_t block_size, uint32_t header_off, int hash_size); + +/* returns the block type (eg. 'r' for ref records. */ +uint8_t block_writer_type(struct block_writer *bw); + +/* appends the record, or -1 if it doesn't fit. */ +int block_writer_add(struct block_writer *w, struct reftable_record *rec); + +/* appends the key restarts, and compress the block if necessary. */ +int block_writer_finish(struct block_writer *w); + +/* clears out internally allocated block_writer members. */ +void block_writer_release(struct block_writer *bw); + +/* Read a block. */ +struct block_reader { + /* offset of the block header; nonzero for the first block in a + * reftable. */ + uint32_t header_off; + + /* the memory block */ + struct reftable_block block; + int hash_size; + + /* size of the data, excluding restart data. */ + uint32_t block_len; + uint8_t *restart_bytes; + uint16_t restart_count; + + /* size of the data in the file. For log blocks, this is the compressed + * size. */ + uint32_t full_block_size; +}; + +/* Iterate over entries in a block */ +struct block_iter { + /* offset within the block of the next entry to read. */ + uint32_t next_off; + struct block_reader *br; + + /* key for last entry we read. */ + struct strbuf last_key; +}; + +/* initializes a block reader. */ +int block_reader_init(struct block_reader *br, struct reftable_block *bl, + uint32_t header_off, uint32_t table_block_size, + int hash_size); + +/* Position `it` at start of the block */ +void block_reader_start(struct block_reader *br, struct block_iter *it); + +/* Position `it` to the `want` key in the block */ +int block_reader_seek(struct block_reader *br, struct block_iter *it, + struct strbuf *want); + +/* Returns the block type (eg. 'r' for refs) */ +uint8_t block_reader_type(struct block_reader *r); + +/* Decodes the first key in the block */ +int block_reader_first_key(struct block_reader *br, struct strbuf *key); + +void block_iter_copy_from(struct block_iter *dest, struct block_iter *src); + +/* return < 0 for error, 0 for OK, > 0 for EOF. */ +int block_iter_next(struct block_iter *it, struct reftable_record *rec); + +/* Seek to `want` with in the block pointed to by `it` */ +int block_iter_seek(struct block_iter *it, struct strbuf *want); + +/* deallocate memory for `it`. The block reader and its block is left intact. */ +void block_iter_close(struct block_iter *it); + +/* size of file header, depending on format version */ +int header_size(int version); + +/* size of file footer, depending on format version */ +int footer_size(int version); + +/* returns a block to its source. */ +void reftable_block_done(struct reftable_block *ret); + +#endif diff --git a/reftable/block_test.c b/reftable/block_test.c new file mode 100644 index 0000000000..cb88af4a56 --- /dev/null +++ b/reftable/block_test.c @@ -0,0 +1,125 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "block.h" + +#include "system.h" +#include "blocksource.h" +#include "basics.h" +#include "constants.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static void test_block_read_write(void) +{ + const int header_off = 21; /* random */ + char *names[30]; + const int N = ARRAY_SIZE(names); + const int block_size = 1024; + struct reftable_block block = { NULL }; + struct block_writer bw = { + .last_key = STRBUF_INIT, + }; + struct reftable_record rec = { + .type = BLOCK_TYPE_REF, + }; + int i = 0; + int n; + struct block_reader br = { 0 }; + struct block_iter it = { .last_key = STRBUF_INIT }; + int j = 0; + struct strbuf want = STRBUF_INIT; + + block.data = reftable_calloc(block_size); + block.len = block_size; + block.source = malloc_block_source(); + block_writer_init(&bw, BLOCK_TYPE_REF, block.data, block_size, + header_off, hash_size(GIT_SHA1_FORMAT_ID)); + + rec.u.ref.refname = ""; + rec.u.ref.value_type = REFTABLE_REF_DELETION; + n = block_writer_add(&bw, &rec); + EXPECT(n == REFTABLE_API_ERROR); + + for (i = 0; i < N; i++) { + char name[100]; + uint8_t hash[GIT_SHA1_RAWSZ]; + snprintf(name, sizeof(name), "branch%02d", i); + memset(hash, i, sizeof(hash)); + + rec.u.ref.refname = name; + rec.u.ref.value_type = REFTABLE_REF_VAL1; + rec.u.ref.value.val1 = hash; + + names[i] = xstrdup(name); + n = block_writer_add(&bw, &rec); + rec.u.ref.refname = NULL; + rec.u.ref.value_type = REFTABLE_REF_DELETION; + EXPECT(n == 0); + } + + n = block_writer_finish(&bw); + EXPECT(n > 0); + + block_writer_release(&bw); + + block_reader_init(&br, &block, header_off, block_size, GIT_SHA1_RAWSZ); + + block_reader_start(&br, &it); + + while (1) { + int r = block_iter_next(&it, &rec); + EXPECT(r >= 0); + if (r > 0) { + break; + } + EXPECT_STREQ(names[j], rec.u.ref.refname); + j++; + } + + reftable_record_release(&rec); + block_iter_close(&it); + + for (i = 0; i < N; i++) { + struct block_iter it = { .last_key = STRBUF_INIT }; + strbuf_reset(&want); + strbuf_addstr(&want, names[i]); + + n = block_reader_seek(&br, &it, &want); + EXPECT(n == 0); + + n = block_iter_next(&it, &rec); + EXPECT(n == 0); + + EXPECT_STREQ(names[i], rec.u.ref.refname); + + want.len--; + n = block_reader_seek(&br, &it, &want); + EXPECT(n == 0); + + n = block_iter_next(&it, &rec); + EXPECT(n == 0); + EXPECT_STREQ(names[10 * (i / 10)], rec.u.ref.refname); + + block_iter_close(&it); + } + + reftable_record_release(&rec); + reftable_block_done(&br.block); + strbuf_release(&want); + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } +} + +int block_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_block_read_write); + return 0; +} diff --git a/reftable/blocksource.c b/reftable/blocksource.c new file mode 100644 index 0000000000..2605371c28 --- /dev/null +++ b/reftable/blocksource.c @@ -0,0 +1,150 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" + +#include "basics.h" +#include "blocksource.h" +#include "reftable-blocksource.h" +#include "reftable-error.h" + +static void strbuf_return_block(void *b, struct reftable_block *dest) +{ + memset(dest->data, 0xff, dest->len); + reftable_free(dest->data); +} + +static void strbuf_close(void *b) +{ +} + +static int strbuf_read_block(void *v, struct reftable_block *dest, uint64_t off, + uint32_t size) +{ + struct strbuf *b = v; + assert(off + size <= b->len); + dest->data = reftable_calloc(size); + memcpy(dest->data, b->buf + off, size); + dest->len = size; + return size; +} + +static uint64_t strbuf_size(void *b) +{ + return ((struct strbuf *)b)->len; +} + +static struct reftable_block_source_vtable strbuf_vtable = { + .size = &strbuf_size, + .read_block = &strbuf_read_block, + .return_block = &strbuf_return_block, + .close = &strbuf_close, +}; + +void block_source_from_strbuf(struct reftable_block_source *bs, + struct strbuf *buf) +{ + assert(!bs->ops); + bs->ops = &strbuf_vtable; + bs->arg = buf; +} + +static void malloc_return_block(void *b, struct reftable_block *dest) +{ + memset(dest->data, 0xff, dest->len); + reftable_free(dest->data); +} + +static struct reftable_block_source_vtable malloc_vtable = { + .return_block = &malloc_return_block, +}; + +static struct reftable_block_source malloc_block_source_instance = { + .ops = &malloc_vtable, +}; + +struct reftable_block_source malloc_block_source(void) +{ + return malloc_block_source_instance; +} + +struct file_block_source { + int fd; + uint64_t size; +}; + +static uint64_t file_size(void *b) +{ + return ((struct file_block_source *)b)->size; +} + +static void file_return_block(void *b, struct reftable_block *dest) +{ + memset(dest->data, 0xff, dest->len); + reftable_free(dest->data); +} + +static void file_close(void *b) +{ + int fd = ((struct file_block_source *)b)->fd; + if (fd > 0) { + close(fd); + ((struct file_block_source *)b)->fd = 0; + } + + reftable_free(b); +} + +static int file_read_block(void *v, struct reftable_block *dest, uint64_t off, + uint32_t size) +{ + struct file_block_source *b = v; + assert(off + size <= b->size); + dest->data = reftable_malloc(size); + if (pread(b->fd, dest->data, size, off) != size) + return -1; + dest->len = size; + return size; +} + +static struct reftable_block_source_vtable file_vtable = { + .size = &file_size, + .read_block = &file_read_block, + .return_block = &file_return_block, + .close = &file_close, +}; + +int reftable_block_source_from_file(struct reftable_block_source *bs, + const char *name) +{ + struct stat st = { 0 }; + int err = 0; + int fd = open(name, O_RDONLY); + struct file_block_source *p = NULL; + if (fd < 0) { + if (errno == ENOENT) { + return REFTABLE_NOT_EXIST_ERROR; + } + return -1; + } + + err = fstat(fd, &st); + if (err < 0) { + close(fd); + return REFTABLE_IO_ERROR; + } + + p = reftable_calloc(sizeof(struct file_block_source)); + p->size = st.st_size; + p->fd = fd; + + assert(!bs->ops); + bs->ops = &file_vtable; + bs->arg = p; + return 0; +} diff --git a/reftable/blocksource.h b/reftable/blocksource.h new file mode 100644 index 0000000000..072e2727ad --- /dev/null +++ b/reftable/blocksource.h @@ -0,0 +1,22 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef BLOCKSOURCE_H +#define BLOCKSOURCE_H + +#include "system.h" + +struct reftable_block_source; + +/* Create an in-memory block source for reading reftables */ +void block_source_from_strbuf(struct reftable_block_source *bs, + struct strbuf *buf); + +struct reftable_block_source malloc_block_source(void); + +#endif diff --git a/reftable/constants.h b/reftable/constants.h new file mode 100644 index 0000000000..5eee72c4c1 --- /dev/null +++ b/reftable/constants.h @@ -0,0 +1,21 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef CONSTANTS_H +#define CONSTANTS_H + +#define BLOCK_TYPE_LOG 'g' +#define BLOCK_TYPE_INDEX 'i' +#define BLOCK_TYPE_REF 'r' +#define BLOCK_TYPE_OBJ 'o' +#define BLOCK_TYPE_ANY 0 + +#define MAX_RESTARTS ((1 << 16) - 1) +#define DEFAULT_BLOCK_SIZE 4096 + +#endif diff --git a/reftable/dump.c b/reftable/dump.c new file mode 100644 index 0000000000..155953d1b8 --- /dev/null +++ b/reftable/dump.c @@ -0,0 +1,107 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "git-compat-util.h" +#include "hash.h" + +#include "reftable-blocksource.h" +#include "reftable-error.h" +#include "reftable-merged.h" +#include "reftable-record.h" +#include "reftable-tests.h" +#include "reftable-writer.h" +#include "reftable-iterator.h" +#include "reftable-reader.h" +#include "reftable-stack.h" +#include "reftable-generic.h" + +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> + +static int compact_stack(const char *stackdir) +{ + struct reftable_stack *stack = NULL; + struct reftable_write_options cfg = { 0 }; + + int err = reftable_new_stack(&stack, stackdir, cfg); + if (err < 0) + goto done; + + err = reftable_stack_compact_all(stack, NULL); + if (err < 0) + goto done; +done: + if (stack) { + reftable_stack_destroy(stack); + } + return err; +} + +static void print_help(void) +{ + printf("usage: dump [-cst] arg\n\n" + "options: \n" + " -c compact\n" + " -t dump table\n" + " -s dump stack\n" + " -6 sha256 hash format\n" + " -h this help\n" + "\n"); +} + +int reftable_dump_main(int argc, char *const *argv) +{ + int err = 0; + int opt_dump_table = 0; + int opt_dump_stack = 0; + int opt_compact = 0; + uint32_t opt_hash_id = GIT_SHA1_FORMAT_ID; + const char *arg = NULL, *argv0 = argv[0]; + + for (; argc > 1; argv++, argc--) + if (*argv[1] != '-') + break; + else if (!strcmp("-t", argv[1])) + opt_dump_table = 1; + else if (!strcmp("-6", argv[1])) + opt_hash_id = GIT_SHA256_FORMAT_ID; + else if (!strcmp("-s", argv[1])) + opt_dump_stack = 1; + else if (!strcmp("-c", argv[1])) + opt_compact = 1; + else if (!strcmp("-?", argv[1]) || !strcmp("-h", argv[1])) { + print_help(); + return 2; + } + + if (argc != 2) { + fprintf(stderr, "need argument\n"); + print_help(); + return 2; + } + + arg = argv[1]; + + if (opt_dump_table) { + err = reftable_reader_print_file(arg); + } else if (opt_dump_stack) { + err = reftable_stack_print_directory(arg, opt_hash_id); + } else if (opt_compact) { + err = compact_stack(arg); + } + + if (err < 0) { + fprintf(stderr, "%s: %s: %s\n", argv0, arg, + reftable_error_str(err)); + return 1; + } + return 0; +} diff --git a/reftable/error.c b/reftable/error.c new file mode 100644 index 0000000000..93941f2145 --- /dev/null +++ b/reftable/error.c @@ -0,0 +1,43 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reftable-error.h" + +#include <stdio.h> + +const char *reftable_error_str(int err) +{ + static char buf[250]; + switch (err) { + case REFTABLE_IO_ERROR: + return "I/O error"; + case REFTABLE_FORMAT_ERROR: + return "corrupt reftable file"; + case REFTABLE_NOT_EXIST_ERROR: + return "file does not exist"; + case REFTABLE_LOCK_ERROR: + return "data is outdated"; + case REFTABLE_API_ERROR: + return "misuse of the reftable API"; + case REFTABLE_ZLIB_ERROR: + return "zlib failure"; + case REFTABLE_NAME_CONFLICT: + return "file/directory conflict"; + case REFTABLE_EMPTY_TABLE_ERROR: + return "wrote empty table"; + case REFTABLE_REFNAME_ERROR: + return "invalid refname"; + case REFTABLE_ENTRY_TOO_BIG_ERROR: + return "entry too large"; + case -1: + return "general error"; + default: + snprintf(buf, sizeof(buf), "unknown error code %d", err); + return buf; + } +} diff --git a/reftable/generic.c b/reftable/generic.c new file mode 100644 index 0000000000..57f8032db9 --- /dev/null +++ b/reftable/generic.c @@ -0,0 +1,180 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "basics.h" +#include "constants.h" +#include "record.h" +#include "generic.h" +#include "reftable-iterator.h" +#include "reftable-generic.h" + +int reftable_table_seek_ref(struct reftable_table *tab, + struct reftable_iterator *it, const char *name) +{ + struct reftable_record rec = { .type = BLOCK_TYPE_REF, + .u.ref = { + .refname = (char *)name, + } }; + return tab->ops->seek_record(tab->table_arg, it, &rec); +} + +int reftable_table_seek_log(struct reftable_table *tab, + struct reftable_iterator *it, const char *name) +{ + struct reftable_record rec = { .type = BLOCK_TYPE_LOG, + .u.log = { + .refname = (char *)name, + .update_index = ~((uint64_t)0), + } }; + return tab->ops->seek_record(tab->table_arg, it, &rec); +} + +int reftable_table_read_ref(struct reftable_table *tab, const char *name, + struct reftable_ref_record *ref) +{ + struct reftable_iterator it = { NULL }; + int err = reftable_table_seek_ref(tab, &it, name); + if (err) + goto done; + + err = reftable_iterator_next_ref(&it, ref); + if (err) + goto done; + + if (strcmp(ref->refname, name) || + reftable_ref_record_is_deletion(ref)) { + reftable_ref_record_release(ref); + err = 1; + goto done; + } + +done: + reftable_iterator_destroy(&it); + return err; +} + +int reftable_table_print(struct reftable_table *tab) { + struct reftable_iterator it = { NULL }; + struct reftable_ref_record ref = { NULL }; + struct reftable_log_record log = { NULL }; + uint32_t hash_id = reftable_table_hash_id(tab); + int err = reftable_table_seek_ref(tab, &it, ""); + if (err < 0) { + return err; + } + + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) { + return err; + } + reftable_ref_record_print(&ref, hash_id); + } + reftable_iterator_destroy(&it); + reftable_ref_record_release(&ref); + + err = reftable_table_seek_log(tab, &it, ""); + if (err < 0) { + return err; + } + while (1) { + err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + break; + } + if (err < 0) { + return err; + } + reftable_log_record_print(&log, hash_id); + } + reftable_iterator_destroy(&it); + reftable_log_record_release(&log); + return 0; +} + +uint64_t reftable_table_max_update_index(struct reftable_table *tab) +{ + return tab->ops->max_update_index(tab->table_arg); +} + +uint64_t reftable_table_min_update_index(struct reftable_table *tab) +{ + return tab->ops->min_update_index(tab->table_arg); +} + +uint32_t reftable_table_hash_id(struct reftable_table *tab) +{ + return tab->ops->hash_id(tab->table_arg); +} + +void reftable_iterator_destroy(struct reftable_iterator *it) +{ + if (!it->ops) { + return; + } + it->ops->close(it->iter_arg); + it->ops = NULL; + FREE_AND_NULL(it->iter_arg); +} + +int reftable_iterator_next_ref(struct reftable_iterator *it, + struct reftable_ref_record *ref) +{ + struct reftable_record rec = { + .type = BLOCK_TYPE_REF, + .u = { + .ref = *ref + }, + }; + int err = iterator_next(it, &rec); + *ref = rec.u.ref; + return err; +} + +int reftable_iterator_next_log(struct reftable_iterator *it, + struct reftable_log_record *log) +{ + struct reftable_record rec = { + .type = BLOCK_TYPE_LOG, + .u = { + .log = *log, + }, + }; + int err = iterator_next(it, &rec); + *log = rec.u.log; + return err; +} + +int iterator_next(struct reftable_iterator *it, struct reftable_record *rec) +{ + return it->ops->next(it->iter_arg, rec); +} + +static int empty_iterator_next(void *arg, struct reftable_record *rec) +{ + return 1; +} + +static void empty_iterator_close(void *arg) +{ +} + +static struct reftable_iterator_vtable empty_vtable = { + .next = &empty_iterator_next, + .close = &empty_iterator_close, +}; + +void iterator_set_empty(struct reftable_iterator *it) +{ + assert(!it->ops); + it->iter_arg = NULL; + it->ops = &empty_vtable; +} diff --git a/reftable/generic.h b/reftable/generic.h new file mode 100644 index 0000000000..98886a0640 --- /dev/null +++ b/reftable/generic.h @@ -0,0 +1,32 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef GENERIC_H +#define GENERIC_H + +#include "record.h" +#include "reftable-generic.h" + +/* generic interface to reftables */ +struct reftable_table_vtable { + int (*seek_record)(void *tab, struct reftable_iterator *it, + struct reftable_record *); + uint32_t (*hash_id)(void *tab); + uint64_t (*min_update_index)(void *tab); + uint64_t (*max_update_index)(void *tab); +}; + +struct reftable_iterator_vtable { + int (*next)(void *iter_arg, struct reftable_record *rec); + void (*close)(void *iter_arg); +}; + +void iterator_set_empty(struct reftable_iterator *it); +int iterator_next(struct reftable_iterator *it, struct reftable_record *rec); + +#endif diff --git a/reftable/iter.c b/reftable/iter.c new file mode 100644 index 0000000000..a8d174c040 --- /dev/null +++ b/reftable/iter.c @@ -0,0 +1,194 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "iter.h" + +#include "system.h" + +#include "block.h" +#include "generic.h" +#include "constants.h" +#include "reader.h" +#include "reftable-error.h" + +int iterator_is_null(struct reftable_iterator *it) +{ + return !it->ops; +} + +static void filtering_ref_iterator_close(void *iter_arg) +{ + struct filtering_ref_iterator *fri = iter_arg; + strbuf_release(&fri->oid); + reftable_iterator_destroy(&fri->it); +} + +static int filtering_ref_iterator_next(void *iter_arg, + struct reftable_record *rec) +{ + struct filtering_ref_iterator *fri = iter_arg; + struct reftable_ref_record *ref = &rec->u.ref; + int err = 0; + while (1) { + err = reftable_iterator_next_ref(&fri->it, ref); + if (err != 0) { + break; + } + + if (fri->double_check) { + struct reftable_iterator it = { NULL }; + + err = reftable_table_seek_ref(&fri->tab, &it, + ref->refname); + if (err == 0) { + err = reftable_iterator_next_ref(&it, ref); + } + + reftable_iterator_destroy(&it); + + if (err < 0) { + break; + } + + if (err > 0) { + continue; + } + } + + if (ref->value_type == REFTABLE_REF_VAL2 && + (!memcmp(fri->oid.buf, ref->value.val2.target_value, + fri->oid.len) || + !memcmp(fri->oid.buf, ref->value.val2.value, + fri->oid.len))) + return 0; + + if (ref->value_type == REFTABLE_REF_VAL1 && + !memcmp(fri->oid.buf, ref->value.val1, fri->oid.len)) { + return 0; + } + } + + reftable_ref_record_release(ref); + return err; +} + +static struct reftable_iterator_vtable filtering_ref_iterator_vtable = { + .next = &filtering_ref_iterator_next, + .close = &filtering_ref_iterator_close, +}; + +void iterator_from_filtering_ref_iterator(struct reftable_iterator *it, + struct filtering_ref_iterator *fri) +{ + assert(!it->ops); + it->iter_arg = fri; + it->ops = &filtering_ref_iterator_vtable; +} + +static void indexed_table_ref_iter_close(void *p) +{ + struct indexed_table_ref_iter *it = p; + block_iter_close(&it->cur); + reftable_block_done(&it->block_reader.block); + reftable_free(it->offsets); + strbuf_release(&it->oid); +} + +static int indexed_table_ref_iter_next_block(struct indexed_table_ref_iter *it) +{ + uint64_t off; + int err = 0; + if (it->offset_idx == it->offset_len) { + it->is_finished = 1; + return 1; + } + + reftable_block_done(&it->block_reader.block); + + off = it->offsets[it->offset_idx++]; + err = reader_init_block_reader(it->r, &it->block_reader, off, + BLOCK_TYPE_REF); + if (err < 0) { + return err; + } + if (err > 0) { + /* indexed block does not exist. */ + return REFTABLE_FORMAT_ERROR; + } + block_reader_start(&it->block_reader, &it->cur); + return 0; +} + +static int indexed_table_ref_iter_next(void *p, struct reftable_record *rec) +{ + struct indexed_table_ref_iter *it = p; + struct reftable_ref_record *ref = &rec->u.ref; + + while (1) { + int err = block_iter_next(&it->cur, rec); + if (err < 0) { + return err; + } + + if (err > 0) { + err = indexed_table_ref_iter_next_block(it); + if (err < 0) { + return err; + } + + if (it->is_finished) { + return 1; + } + continue; + } + /* BUG */ + if (!memcmp(it->oid.buf, ref->value.val2.target_value, + it->oid.len) || + !memcmp(it->oid.buf, ref->value.val2.value, it->oid.len)) { + return 0; + } + } +} + +int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest, + struct reftable_reader *r, uint8_t *oid, + int oid_len, uint64_t *offsets, int offset_len) +{ + struct indexed_table_ref_iter empty = INDEXED_TABLE_REF_ITER_INIT; + struct indexed_table_ref_iter *itr = + reftable_calloc(sizeof(struct indexed_table_ref_iter)); + int err = 0; + + *itr = empty; + itr->r = r; + strbuf_add(&itr->oid, oid, oid_len); + + itr->offsets = offsets; + itr->offset_len = offset_len; + + err = indexed_table_ref_iter_next_block(itr); + if (err < 0) { + reftable_free(itr); + } else { + *dest = itr; + } + return err; +} + +static struct reftable_iterator_vtable indexed_table_ref_iter_vtable = { + .next = &indexed_table_ref_iter_next, + .close = &indexed_table_ref_iter_close, +}; + +void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it, + struct indexed_table_ref_iter *itr) +{ + assert(!it->ops); + it->iter_arg = itr; + it->ops = &indexed_table_ref_iter_vtable; +} diff --git a/reftable/iter.h b/reftable/iter.h new file mode 100644 index 0000000000..09eb0cbfa5 --- /dev/null +++ b/reftable/iter.h @@ -0,0 +1,69 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef ITER_H +#define ITER_H + +#include "system.h" +#include "block.h" +#include "record.h" + +#include "reftable-iterator.h" +#include "reftable-generic.h" + +/* Returns true for a zeroed out iterator, such as the one returned from + * iterator_destroy. */ +int iterator_is_null(struct reftable_iterator *it); + +/* iterator that produces only ref records that point to `oid` */ +struct filtering_ref_iterator { + int double_check; + struct reftable_table tab; + struct strbuf oid; + struct reftable_iterator it; +}; +#define FILTERING_REF_ITERATOR_INIT \ + { \ + .oid = STRBUF_INIT \ + } + +void iterator_from_filtering_ref_iterator(struct reftable_iterator *, + struct filtering_ref_iterator *); + +/* iterator that produces only ref records that point to `oid`, + * but using the object index. + */ +struct indexed_table_ref_iter { + struct reftable_reader *r; + struct strbuf oid; + + /* mutable */ + uint64_t *offsets; + + /* Points to the next offset to read. */ + int offset_idx; + int offset_len; + struct block_reader block_reader; + struct block_iter cur; + int is_finished; +}; + +#define INDEXED_TABLE_REF_ITER_INIT \ + { \ + .cur = { .last_key = STRBUF_INIT }, .oid = STRBUF_INIT, \ + } + +void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it, + struct indexed_table_ref_iter *itr); + +/* Takes ownership of `offsets` */ +int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest, + struct reftable_reader *r, uint8_t *oid, + int oid_len, uint64_t *offsets, int offset_len); + +#endif diff --git a/reftable/merged.c b/reftable/merged.c new file mode 100644 index 0000000000..2a6efa110d --- /dev/null +++ b/reftable/merged.c @@ -0,0 +1,361 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "merged.h" + +#include "constants.h" +#include "iter.h" +#include "pq.h" +#include "reader.h" +#include "record.h" +#include "generic.h" +#include "reftable-merged.h" +#include "reftable-error.h" +#include "system.h" + +static int merged_iter_init(struct merged_iter *mi) +{ + int i = 0; + for (i = 0; i < mi->stack_len; i++) { + struct reftable_record rec = reftable_new_record(mi->typ); + int err = iterator_next(&mi->stack[i], &rec); + if (err < 0) { + return err; + } + + if (err > 0) { + reftable_iterator_destroy(&mi->stack[i]); + reftable_record_release(&rec); + } else { + struct pq_entry e = { + .rec = rec, + .index = i, + }; + merged_iter_pqueue_add(&mi->pq, e); + } + } + + return 0; +} + +static void merged_iter_close(void *p) +{ + struct merged_iter *mi = p; + int i = 0; + merged_iter_pqueue_release(&mi->pq); + for (i = 0; i < mi->stack_len; i++) { + reftable_iterator_destroy(&mi->stack[i]); + } + reftable_free(mi->stack); +} + +static int merged_iter_advance_nonnull_subiter(struct merged_iter *mi, + size_t idx) +{ + struct pq_entry e = { + .rec = reftable_new_record(mi->typ), + .index = idx, + }; + int err = iterator_next(&mi->stack[idx], &e.rec); + if (err < 0) + return err; + + if (err > 0) { + reftable_iterator_destroy(&mi->stack[idx]); + reftable_record_release(&e.rec); + return 0; + } + + merged_iter_pqueue_add(&mi->pq, e); + return 0; +} + +static int merged_iter_advance_subiter(struct merged_iter *mi, size_t idx) +{ + if (iterator_is_null(&mi->stack[idx])) + return 0; + return merged_iter_advance_nonnull_subiter(mi, idx); +} + +static int merged_iter_next_entry(struct merged_iter *mi, + struct reftable_record *rec) +{ + struct strbuf entry_key = STRBUF_INIT; + struct pq_entry entry = { 0 }; + int err = 0; + + if (merged_iter_pqueue_is_empty(mi->pq)) + return 1; + + entry = merged_iter_pqueue_remove(&mi->pq); + err = merged_iter_advance_subiter(mi, entry.index); + if (err < 0) + return err; + + /* + One can also use reftable as datacenter-local storage, where the ref + database is maintained in globally consistent database (eg. + CockroachDB or Spanner). In this scenario, replication delays together + with compaction may cause newer tables to contain older entries. In + such a deployment, the loop below must be changed to collect all + entries for the same key, and return new the newest one. + */ + reftable_record_key(&entry.rec, &entry_key); + while (!merged_iter_pqueue_is_empty(mi->pq)) { + struct pq_entry top = merged_iter_pqueue_top(mi->pq); + struct strbuf k = STRBUF_INIT; + int err = 0, cmp = 0; + + reftable_record_key(&top.rec, &k); + + cmp = strbuf_cmp(&k, &entry_key); + strbuf_release(&k); + + if (cmp > 0) { + break; + } + + merged_iter_pqueue_remove(&mi->pq); + err = merged_iter_advance_subiter(mi, top.index); + if (err < 0) { + return err; + } + reftable_record_release(&top.rec); + } + + reftable_record_copy_from(rec, &entry.rec, hash_size(mi->hash_id)); + reftable_record_release(&entry.rec); + strbuf_release(&entry_key); + return 0; +} + +static int merged_iter_next(struct merged_iter *mi, struct reftable_record *rec) +{ + while (1) { + int err = merged_iter_next_entry(mi, rec); + if (err == 0 && mi->suppress_deletions && + reftable_record_is_deletion(rec)) { + continue; + } + + return err; + } +} + +static int merged_iter_next_void(void *p, struct reftable_record *rec) +{ + struct merged_iter *mi = p; + if (merged_iter_pqueue_is_empty(mi->pq)) + return 1; + + return merged_iter_next(mi, rec); +} + +static struct reftable_iterator_vtable merged_iter_vtable = { + .next = &merged_iter_next_void, + .close = &merged_iter_close, +}; + +static void iterator_from_merged_iter(struct reftable_iterator *it, + struct merged_iter *mi) +{ + assert(!it->ops); + it->iter_arg = mi; + it->ops = &merged_iter_vtable; +} + +int reftable_new_merged_table(struct reftable_merged_table **dest, + struct reftable_table *stack, int n, + uint32_t hash_id) +{ + struct reftable_merged_table *m = NULL; + uint64_t last_max = 0; + uint64_t first_min = 0; + int i = 0; + for (i = 0; i < n; i++) { + uint64_t min = reftable_table_min_update_index(&stack[i]); + uint64_t max = reftable_table_max_update_index(&stack[i]); + + if (reftable_table_hash_id(&stack[i]) != hash_id) { + return REFTABLE_FORMAT_ERROR; + } + if (i == 0 || min < first_min) { + first_min = min; + } + if (i == 0 || max > last_max) { + last_max = max; + } + } + + m = reftable_calloc(sizeof(struct reftable_merged_table)); + m->stack = stack; + m->stack_len = n; + m->min = first_min; + m->max = last_max; + m->hash_id = hash_id; + *dest = m; + return 0; +} + +/* clears the list of subtable, without affecting the readers themselves. */ +void merged_table_release(struct reftable_merged_table *mt) +{ + FREE_AND_NULL(mt->stack); + mt->stack_len = 0; +} + +void reftable_merged_table_free(struct reftable_merged_table *mt) +{ + if (!mt) { + return; + } + merged_table_release(mt); + reftable_free(mt); +} + +uint64_t +reftable_merged_table_max_update_index(struct reftable_merged_table *mt) +{ + return mt->max; +} + +uint64_t +reftable_merged_table_min_update_index(struct reftable_merged_table *mt) +{ + return mt->min; +} + +static int reftable_table_seek_record(struct reftable_table *tab, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + return tab->ops->seek_record(tab->table_arg, it, rec); +} + +static int merged_table_seek_record(struct reftable_merged_table *mt, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + struct reftable_iterator *iters = reftable_calloc( + sizeof(struct reftable_iterator) * mt->stack_len); + struct merged_iter merged = { + .stack = iters, + .typ = reftable_record_type(rec), + .hash_id = mt->hash_id, + .suppress_deletions = mt->suppress_deletions, + }; + int n = 0; + int err = 0; + int i = 0; + for (i = 0; i < mt->stack_len && err == 0; i++) { + int e = reftable_table_seek_record(&mt->stack[i], &iters[n], + rec); + if (e < 0) { + err = e; + } + if (e == 0) { + n++; + } + } + if (err < 0) { + int i = 0; + for (i = 0; i < n; i++) { + reftable_iterator_destroy(&iters[i]); + } + reftable_free(iters); + return err; + } + + merged.stack_len = n; + err = merged_iter_init(&merged); + if (err < 0) { + merged_iter_close(&merged); + return err; + } else { + struct merged_iter *p = + reftable_malloc(sizeof(struct merged_iter)); + *p = merged; + iterator_from_merged_iter(it, p); + } + return 0; +} + +int reftable_merged_table_seek_ref(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name) +{ + struct reftable_record rec = { + .type = BLOCK_TYPE_REF, + .u.ref = { + .refname = (char *)name, + }, + }; + return merged_table_seek_record(mt, it, &rec); +} + +int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name, uint64_t update_index) +{ + struct reftable_record rec = { .type = BLOCK_TYPE_LOG, + .u.log = { + .refname = (char *)name, + .update_index = update_index, + } }; + return merged_table_seek_record(mt, it, &rec); +} + +int reftable_merged_table_seek_log(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name) +{ + uint64_t max = ~((uint64_t)0); + return reftable_merged_table_seek_log_at(mt, it, name, max); +} + +uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *mt) +{ + return mt->hash_id; +} + +static int reftable_merged_table_seek_void(void *tab, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + return merged_table_seek_record(tab, it, rec); +} + +static uint32_t reftable_merged_table_hash_id_void(void *tab) +{ + return reftable_merged_table_hash_id(tab); +} + +static uint64_t reftable_merged_table_min_update_index_void(void *tab) +{ + return reftable_merged_table_min_update_index(tab); +} + +static uint64_t reftable_merged_table_max_update_index_void(void *tab) +{ + return reftable_merged_table_max_update_index(tab); +} + +static struct reftable_table_vtable merged_table_vtable = { + .seek_record = reftable_merged_table_seek_void, + .hash_id = reftable_merged_table_hash_id_void, + .min_update_index = reftable_merged_table_min_update_index_void, + .max_update_index = reftable_merged_table_max_update_index_void, +}; + +void reftable_table_from_merged_table(struct reftable_table *tab, + struct reftable_merged_table *merged) +{ + assert(!tab->ops); + tab->ops = &merged_table_vtable; + tab->table_arg = merged; +} diff --git a/reftable/merged.h b/reftable/merged.h new file mode 100644 index 0000000000..7d9f95d27e --- /dev/null +++ b/reftable/merged.h @@ -0,0 +1,38 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef MERGED_H +#define MERGED_H + +#include "pq.h" + +struct reftable_merged_table { + struct reftable_table *stack; + size_t stack_len; + uint32_t hash_id; + + /* If unset, produce deletions. This is useful for compaction. For the + * full stack, deletions should be produced. */ + int suppress_deletions; + + uint64_t min; + uint64_t max; +}; + +struct merged_iter { + struct reftable_iterator *stack; + uint32_t hash_id; + size_t stack_len; + uint8_t typ; + int suppress_deletions; + struct merged_iter_pqueue pq; +}; + +void merged_table_release(struct reftable_merged_table *mt); + +#endif diff --git a/reftable/merged_test.c b/reftable/merged_test.c new file mode 100644 index 0000000000..d08c16abef --- /dev/null +++ b/reftable/merged_test.c @@ -0,0 +1,468 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "merged.h" + +#include "system.h" + +#include "basics.h" +#include "blocksource.h" +#include "constants.h" +#include "reader.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-merged.h" +#include "reftable-tests.h" +#include "reftable-generic.h" +#include "reftable-writer.h" + +static void write_test_table(struct strbuf *buf, + struct reftable_ref_record refs[], int n) +{ + uint64_t min = 0xffffffff; + uint64_t max = 0; + int i = 0; + int err; + + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_writer *w = NULL; + for (i = 0; i < n; i++) { + uint64_t ui = refs[i].update_index; + if (ui > max) { + max = ui; + } + if (ui < min) { + min = ui; + } + } + + w = reftable_new_writer(&strbuf_add_void, buf, &opts); + reftable_writer_set_limits(w, min, max); + + for (i = 0; i < n; i++) { + uint64_t before = refs[i].update_index; + int n = reftable_writer_add_ref(w, &refs[i]); + EXPECT(n == 0); + EXPECT(before == refs[i].update_index); + } + + err = reftable_writer_close(w); + EXPECT_ERR(err); + + reftable_writer_free(w); +} + +static void write_test_log_table(struct strbuf *buf, + struct reftable_log_record logs[], int n, + uint64_t update_index) +{ + int i = 0; + int err; + + struct reftable_write_options opts = { + .block_size = 256, + .exact_log_message = 1, + }; + struct reftable_writer *w = NULL; + w = reftable_new_writer(&strbuf_add_void, buf, &opts); + reftable_writer_set_limits(w, update_index, update_index); + + for (i = 0; i < n; i++) { + int err = reftable_writer_add_log(w, &logs[i]); + EXPECT_ERR(err); + } + + err = reftable_writer_close(w); + EXPECT_ERR(err); + + reftable_writer_free(w); +} + +static struct reftable_merged_table * +merged_table_from_records(struct reftable_ref_record **refs, + struct reftable_block_source **source, + struct reftable_reader ***readers, int *sizes, + struct strbuf *buf, int n) +{ + int i = 0; + struct reftable_merged_table *mt = NULL; + int err; + struct reftable_table *tabs = + reftable_calloc(n * sizeof(struct reftable_table)); + *readers = reftable_calloc(n * sizeof(struct reftable_reader *)); + *source = reftable_calloc(n * sizeof(**source)); + for (i = 0; i < n; i++) { + write_test_table(&buf[i], refs[i], sizes[i]); + block_source_from_strbuf(&(*source)[i], &buf[i]); + + err = reftable_new_reader(&(*readers)[i], &(*source)[i], + "name"); + EXPECT_ERR(err); + reftable_table_from_reader(&tabs[i], (*readers)[i]); + } + + err = reftable_new_merged_table(&mt, tabs, n, GIT_SHA1_FORMAT_ID); + EXPECT_ERR(err); + return mt; +} + +static void readers_destroy(struct reftable_reader **readers, size_t n) +{ + int i = 0; + for (; i < n; i++) + reftable_reader_free(readers[i]); + reftable_free(readers); +} + +static void test_merged_between(void) +{ + uint8_t hash1[GIT_SHA1_RAWSZ] = { 1, 2, 3, 0 }; + + struct reftable_ref_record r1[] = { { + .refname = "b", + .update_index = 1, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash1, + } }; + struct reftable_ref_record r2[] = { { + .refname = "a", + .update_index = 2, + .value_type = REFTABLE_REF_DELETION, + } }; + + struct reftable_ref_record *refs[] = { r1, r2 }; + int sizes[] = { 1, 1 }; + struct strbuf bufs[2] = { STRBUF_INIT, STRBUF_INIT }; + struct reftable_block_source *bs = NULL; + struct reftable_reader **readers = NULL; + struct reftable_merged_table *mt = + merged_table_from_records(refs, &bs, &readers, sizes, bufs, 2); + int i; + struct reftable_ref_record ref = { NULL }; + struct reftable_iterator it = { NULL }; + int err = reftable_merged_table_seek_ref(mt, &it, "a"); + EXPECT_ERR(err); + + err = reftable_iterator_next_ref(&it, &ref); + EXPECT_ERR(err); + EXPECT(ref.update_index == 2); + reftable_ref_record_release(&ref); + reftable_iterator_destroy(&it); + readers_destroy(readers, 2); + reftable_merged_table_free(mt); + for (i = 0; i < ARRAY_SIZE(bufs); i++) { + strbuf_release(&bufs[i]); + } + reftable_free(bs); +} + +static void test_merged(void) +{ + uint8_t hash1[GIT_SHA1_RAWSZ] = { 1 }; + uint8_t hash2[GIT_SHA1_RAWSZ] = { 2 }; + struct reftable_ref_record r1[] = { + { + .refname = "a", + .update_index = 1, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash1, + }, + { + .refname = "b", + .update_index = 1, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash1, + }, + { + .refname = "c", + .update_index = 1, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash1, + } + }; + struct reftable_ref_record r2[] = { { + .refname = "a", + .update_index = 2, + .value_type = REFTABLE_REF_DELETION, + } }; + struct reftable_ref_record r3[] = { + { + .refname = "c", + .update_index = 3, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash2, + }, + { + .refname = "d", + .update_index = 3, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash1, + }, + }; + + struct reftable_ref_record *want[] = { + &r2[0], + &r1[1], + &r3[0], + &r3[1], + }; + + struct reftable_ref_record *refs[] = { r1, r2, r3 }; + int sizes[3] = { 3, 1, 2 }; + struct strbuf bufs[3] = { STRBUF_INIT, STRBUF_INIT, STRBUF_INIT }; + struct reftable_block_source *bs = NULL; + struct reftable_reader **readers = NULL; + struct reftable_merged_table *mt = + merged_table_from_records(refs, &bs, &readers, sizes, bufs, 3); + + struct reftable_iterator it = { NULL }; + int err = reftable_merged_table_seek_ref(mt, &it, "a"); + struct reftable_ref_record *out = NULL; + size_t len = 0; + size_t cap = 0; + int i = 0; + + EXPECT_ERR(err); + EXPECT(reftable_merged_table_hash_id(mt) == GIT_SHA1_FORMAT_ID); + EXPECT(reftable_merged_table_min_update_index(mt) == 1); + + while (len < 100) { /* cap loops/recursion. */ + struct reftable_ref_record ref = { NULL }; + int err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (len == cap) { + cap = 2 * cap + 1; + out = reftable_realloc( + out, sizeof(struct reftable_ref_record) * cap); + } + out[len++] = ref; + } + reftable_iterator_destroy(&it); + + EXPECT(ARRAY_SIZE(want) == len); + for (i = 0; i < len; i++) { + EXPECT(reftable_ref_record_equal(want[i], &out[i], + GIT_SHA1_RAWSZ)); + } + for (i = 0; i < len; i++) { + reftable_ref_record_release(&out[i]); + } + reftable_free(out); + + for (i = 0; i < 3; i++) { + strbuf_release(&bufs[i]); + } + readers_destroy(readers, 3); + reftable_merged_table_free(mt); + reftable_free(bs); +} + +static struct reftable_merged_table * +merged_table_from_log_records(struct reftable_log_record **logs, + struct reftable_block_source **source, + struct reftable_reader ***readers, int *sizes, + struct strbuf *buf, int n) +{ + int i = 0; + struct reftable_merged_table *mt = NULL; + int err; + struct reftable_table *tabs = + reftable_calloc(n * sizeof(struct reftable_table)); + *readers = reftable_calloc(n * sizeof(struct reftable_reader *)); + *source = reftable_calloc(n * sizeof(**source)); + for (i = 0; i < n; i++) { + write_test_log_table(&buf[i], logs[i], sizes[i], i + 1); + block_source_from_strbuf(&(*source)[i], &buf[i]); + + err = reftable_new_reader(&(*readers)[i], &(*source)[i], + "name"); + EXPECT_ERR(err); + reftable_table_from_reader(&tabs[i], (*readers)[i]); + } + + err = reftable_new_merged_table(&mt, tabs, n, GIT_SHA1_FORMAT_ID); + EXPECT_ERR(err); + return mt; +} + +static void test_merged_logs(void) +{ + uint8_t hash1[GIT_SHA1_RAWSZ] = { 1 }; + uint8_t hash2[GIT_SHA1_RAWSZ] = { 2 }; + uint8_t hash3[GIT_SHA1_RAWSZ] = { 3 }; + struct reftable_log_record r1[] = { + { + .refname = "a", + .update_index = 2, + .value_type = REFTABLE_LOG_UPDATE, + .value.update = { + .old_hash = hash2, + /* deletion */ + .name = "jane doe", + .email = "jane@invalid", + .message = "message2", + } + }, + { + .refname = "a", + .update_index = 1, + .value_type = REFTABLE_LOG_UPDATE, + .value.update = { + .old_hash = hash1, + .new_hash = hash2, + .name = "jane doe", + .email = "jane@invalid", + .message = "message1", + } + }, + }; + struct reftable_log_record r2[] = { + { + .refname = "a", + .update_index = 3, + .value_type = REFTABLE_LOG_UPDATE, + .value.update = { + .new_hash = hash3, + .name = "jane doe", + .email = "jane@invalid", + .message = "message3", + } + }, + }; + struct reftable_log_record r3[] = { + { + .refname = "a", + .update_index = 2, + .value_type = REFTABLE_LOG_DELETION, + }, + }; + struct reftable_log_record *want[] = { + &r2[0], + &r3[0], + &r1[1], + }; + + struct reftable_log_record *logs[] = { r1, r2, r3 }; + int sizes[3] = { 2, 1, 1 }; + struct strbuf bufs[3] = { STRBUF_INIT, STRBUF_INIT, STRBUF_INIT }; + struct reftable_block_source *bs = NULL; + struct reftable_reader **readers = NULL; + struct reftable_merged_table *mt = merged_table_from_log_records( + logs, &bs, &readers, sizes, bufs, 3); + + struct reftable_iterator it = { NULL }; + int err = reftable_merged_table_seek_log(mt, &it, "a"); + struct reftable_log_record *out = NULL; + size_t len = 0; + size_t cap = 0; + int i = 0; + + EXPECT_ERR(err); + EXPECT(reftable_merged_table_hash_id(mt) == GIT_SHA1_FORMAT_ID); + EXPECT(reftable_merged_table_min_update_index(mt) == 1); + + while (len < 100) { /* cap loops/recursion. */ + struct reftable_log_record log = { NULL }; + int err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + break; + } + if (len == cap) { + cap = 2 * cap + 1; + out = reftable_realloc( + out, sizeof(struct reftable_log_record) * cap); + } + out[len++] = log; + } + reftable_iterator_destroy(&it); + + EXPECT(ARRAY_SIZE(want) == len); + for (i = 0; i < len; i++) { + EXPECT(reftable_log_record_equal(want[i], &out[i], + GIT_SHA1_RAWSZ)); + } + + err = reftable_merged_table_seek_log_at(mt, &it, "a", 2); + EXPECT_ERR(err); + reftable_log_record_release(&out[0]); + err = reftable_iterator_next_log(&it, &out[0]); + EXPECT_ERR(err); + EXPECT(reftable_log_record_equal(&out[0], &r3[0], GIT_SHA1_RAWSZ)); + reftable_iterator_destroy(&it); + + for (i = 0; i < len; i++) { + reftable_log_record_release(&out[i]); + } + reftable_free(out); + + for (i = 0; i < 3; i++) { + strbuf_release(&bufs[i]); + } + readers_destroy(readers, 3); + reftable_merged_table_free(mt); + reftable_free(bs); +} + +static void test_default_write_opts(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + struct reftable_ref_record rec = { + .refname = "master", + .update_index = 1, + }; + int err; + struct reftable_block_source source = { NULL }; + struct reftable_table *tab = reftable_calloc(sizeof(*tab) * 1); + uint32_t hash_id; + struct reftable_reader *rd = NULL; + struct reftable_merged_table *merged = NULL; + + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_add_ref(w, &rec); + EXPECT_ERR(err); + + err = reftable_writer_close(w); + EXPECT_ERR(err); + reftable_writer_free(w); + + block_source_from_strbuf(&source, &buf); + + err = reftable_new_reader(&rd, &source, "filename"); + EXPECT_ERR(err); + + hash_id = reftable_reader_hash_id(rd); + EXPECT(hash_id == GIT_SHA1_FORMAT_ID); + + reftable_table_from_reader(&tab[0], rd); + err = reftable_new_merged_table(&merged, tab, 1, GIT_SHA1_FORMAT_ID); + EXPECT_ERR(err); + + reftable_reader_free(rd); + reftable_merged_table_free(merged); + strbuf_release(&buf); +} + +/* XXX test refs_for(oid) */ + +int merged_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_merged_logs); + RUN_TEST(test_merged_between); + RUN_TEST(test_merged); + RUN_TEST(test_default_write_opts); + return 0; +} diff --git a/reftable/pq.c b/reftable/pq.c new file mode 100644 index 0000000000..96ca6dd37b --- /dev/null +++ b/reftable/pq.c @@ -0,0 +1,106 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "pq.h" + +#include "reftable-record.h" +#include "system.h" +#include "basics.h" + +int pq_less(struct pq_entry *a, struct pq_entry *b) +{ + struct strbuf ak = STRBUF_INIT; + struct strbuf bk = STRBUF_INIT; + int cmp = 0; + reftable_record_key(&a->rec, &ak); + reftable_record_key(&b->rec, &bk); + + cmp = strbuf_cmp(&ak, &bk); + + strbuf_release(&ak); + strbuf_release(&bk); + + if (cmp == 0) + return a->index > b->index; + + return cmp < 0; +} + +struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq) +{ + return pq.heap[0]; +} + +int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq) +{ + return pq.len == 0; +} + +struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq) +{ + int i = 0; + struct pq_entry e = pq->heap[0]; + pq->heap[0] = pq->heap[pq->len - 1]; + pq->len--; + + i = 0; + while (i < pq->len) { + int min = i; + int j = 2 * i + 1; + int k = 2 * i + 2; + if (j < pq->len && pq_less(&pq->heap[j], &pq->heap[i])) { + min = j; + } + if (k < pq->len && pq_less(&pq->heap[k], &pq->heap[min])) { + min = k; + } + + if (min == i) { + break; + } + + SWAP(pq->heap[i], pq->heap[min]); + i = min; + } + + return e; +} + +void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e) +{ + int i = 0; + + if (pq->len == pq->cap) { + pq->cap = 2 * pq->cap + 1; + pq->heap = reftable_realloc(pq->heap, + pq->cap * sizeof(struct pq_entry)); + } + + pq->heap[pq->len++] = e; + i = pq->len - 1; + while (i > 0) { + int j = (i - 1) / 2; + if (pq_less(&pq->heap[j], &pq->heap[i])) { + break; + } + + SWAP(pq->heap[j], pq->heap[i]); + + i = j; + } +} + +void merged_iter_pqueue_release(struct merged_iter_pqueue *pq) +{ + int i = 0; + for (i = 0; i < pq->len; i++) { + reftable_record_release(&pq->heap[i].rec); + } + FREE_AND_NULL(pq->heap); + pq->len = pq->cap = 0; +} diff --git a/reftable/pq.h b/reftable/pq.h new file mode 100644 index 0000000000..56fc1b6d87 --- /dev/null +++ b/reftable/pq.h @@ -0,0 +1,33 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef PQ_H +#define PQ_H + +#include "record.h" + +struct pq_entry { + int index; + struct reftable_record rec; +}; + +struct merged_iter_pqueue { + struct pq_entry *heap; + size_t len; + size_t cap; +}; + +struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq); +int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq); +void merged_iter_pqueue_check(struct merged_iter_pqueue pq); +struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq); +void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e); +void merged_iter_pqueue_release(struct merged_iter_pqueue *pq); +int pq_less(struct pq_entry *a, struct pq_entry *b); + +#endif diff --git a/reftable/pq_test.c b/reftable/pq_test.c new file mode 100644 index 0000000000..7de5e886f3 --- /dev/null +++ b/reftable/pq_test.c @@ -0,0 +1,79 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" + +#include "basics.h" +#include "constants.h" +#include "pq.h" +#include "record.h" +#include "reftable-tests.h" +#include "test_framework.h" + +void merged_iter_pqueue_check(struct merged_iter_pqueue pq) +{ + int i; + for (i = 1; i < pq.len; i++) { + int parent = (i - 1) / 2; + + EXPECT(pq_less(&pq.heap[parent], &pq.heap[i])); + } +} + +static void test_pq(void) +{ + char *names[54] = { NULL }; + int N = ARRAY_SIZE(names) - 1; + + struct merged_iter_pqueue pq = { NULL }; + char *last = NULL; + + int i = 0; + for (i = 0; i < N; i++) { + char name[100]; + snprintf(name, sizeof(name), "%02d", i); + names[i] = xstrdup(name); + } + + i = 1; + do { + struct pq_entry e = { .rec = { .type = BLOCK_TYPE_REF, + .u.ref = { + .refname = names[i], + } } }; + merged_iter_pqueue_add(&pq, e); + merged_iter_pqueue_check(pq); + i = (i * 7) % N; + } while (i != 1); + + while (!merged_iter_pqueue_is_empty(pq)) { + struct pq_entry e = merged_iter_pqueue_remove(&pq); + struct reftable_record *rec = &e.rec; + merged_iter_pqueue_check(pq); + + EXPECT(reftable_record_type(rec) == BLOCK_TYPE_REF); + if (last) { + EXPECT(strcmp(last, rec->u.ref.refname) < 0); + } + // this is names[i], so don't dealloc. + last = rec->u.ref.refname; + rec->u.ref.refname = NULL; + reftable_record_release(rec); + } + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } + + merged_iter_pqueue_release(&pq); +} + +int pq_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_pq); + return 0; +} diff --git a/reftable/publicbasics.c b/reftable/publicbasics.c new file mode 100644 index 0000000000..0ad7d5c0ff --- /dev/null +++ b/reftable/publicbasics.c @@ -0,0 +1,65 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reftable-malloc.h" + +#include "basics.h" +#include "system.h" + +static void *(*reftable_malloc_ptr)(size_t sz); +static void *(*reftable_realloc_ptr)(void *, size_t); +static void (*reftable_free_ptr)(void *); + +void *reftable_malloc(size_t sz) +{ + if (reftable_malloc_ptr) + return (*reftable_malloc_ptr)(sz); + return malloc(sz); +} + +void *reftable_realloc(void *p, size_t sz) +{ + if (reftable_realloc_ptr) + return (*reftable_realloc_ptr)(p, sz); + return realloc(p, sz); +} + +void reftable_free(void *p) +{ + if (reftable_free_ptr) + reftable_free_ptr(p); + else + free(p); +} + +void *reftable_calloc(size_t sz) +{ + void *p = reftable_malloc(sz); + memset(p, 0, sz); + return p; +} + +void reftable_set_alloc(void *(*malloc)(size_t), + void *(*realloc)(void *, size_t), void (*free)(void *)) +{ + reftable_malloc_ptr = malloc; + reftable_realloc_ptr = realloc; + reftable_free_ptr = free; +} + +int hash_size(uint32_t id) +{ + switch (id) { + case 0: + case GIT_SHA1_FORMAT_ID: + return GIT_SHA1_RAWSZ; + case GIT_SHA256_FORMAT_ID: + return GIT_SHA256_RAWSZ; + } + abort(); +} diff --git a/reftable/reader.c b/reftable/reader.c new file mode 100644 index 0000000000..54b4025105 --- /dev/null +++ b/reftable/reader.c @@ -0,0 +1,816 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reader.h" + +#include "system.h" +#include "block.h" +#include "constants.h" +#include "generic.h" +#include "iter.h" +#include "record.h" +#include "reftable-error.h" +#include "reftable-generic.h" +#include "tree.h" + +uint64_t block_source_size(struct reftable_block_source *source) +{ + return source->ops->size(source->arg); +} + +int block_source_read_block(struct reftable_block_source *source, + struct reftable_block *dest, uint64_t off, + uint32_t size) +{ + int result = source->ops->read_block(source->arg, dest, off, size); + dest->source = *source; + return result; +} + +void block_source_close(struct reftable_block_source *source) +{ + if (!source->ops) { + return; + } + + source->ops->close(source->arg); + source->ops = NULL; +} + +static struct reftable_reader_offsets * +reader_offsets_for(struct reftable_reader *r, uint8_t typ) +{ + switch (typ) { + case BLOCK_TYPE_REF: + return &r->ref_offsets; + case BLOCK_TYPE_LOG: + return &r->log_offsets; + case BLOCK_TYPE_OBJ: + return &r->obj_offsets; + } + abort(); +} + +static int reader_get_block(struct reftable_reader *r, + struct reftable_block *dest, uint64_t off, + uint32_t sz) +{ + if (off >= r->size) + return 0; + + if (off + sz > r->size) { + sz = r->size - off; + } + + return block_source_read_block(&r->source, dest, off, sz); +} + +uint32_t reftable_reader_hash_id(struct reftable_reader *r) +{ + return r->hash_id; +} + +const char *reader_name(struct reftable_reader *r) +{ + return r->name; +} + +static int parse_footer(struct reftable_reader *r, uint8_t *footer, + uint8_t *header) +{ + uint8_t *f = footer; + uint8_t first_block_typ; + int err = 0; + uint32_t computed_crc; + uint32_t file_crc; + + if (memcmp(f, "REFT", 4)) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + f += 4; + + if (memcmp(footer, header, header_size(r->version))) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + f++; + r->block_size = get_be24(f); + + f += 3; + r->min_update_index = get_be64(f); + f += 8; + r->max_update_index = get_be64(f); + f += 8; + + if (r->version == 1) { + r->hash_id = GIT_SHA1_FORMAT_ID; + } else { + r->hash_id = get_be32(f); + switch (r->hash_id) { + case GIT_SHA1_FORMAT_ID: + break; + case GIT_SHA256_FORMAT_ID: + break; + default: + err = REFTABLE_FORMAT_ERROR; + goto done; + } + f += 4; + } + + r->ref_offsets.index_offset = get_be64(f); + f += 8; + + r->obj_offsets.offset = get_be64(f); + f += 8; + + r->object_id_len = r->obj_offsets.offset & ((1 << 5) - 1); + r->obj_offsets.offset >>= 5; + + r->obj_offsets.index_offset = get_be64(f); + f += 8; + r->log_offsets.offset = get_be64(f); + f += 8; + r->log_offsets.index_offset = get_be64(f); + f += 8; + + computed_crc = crc32(0, footer, f - footer); + file_crc = get_be32(f); + f += 4; + if (computed_crc != file_crc) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + first_block_typ = header[header_size(r->version)]; + r->ref_offsets.is_present = (first_block_typ == BLOCK_TYPE_REF); + r->ref_offsets.offset = 0; + r->log_offsets.is_present = (first_block_typ == BLOCK_TYPE_LOG || + r->log_offsets.offset > 0); + r->obj_offsets.is_present = r->obj_offsets.offset > 0; + if (r->obj_offsets.is_present && !r->object_id_len) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + err = 0; +done: + return err; +} + +int init_reader(struct reftable_reader *r, struct reftable_block_source *source, + const char *name) +{ + struct reftable_block footer = { NULL }; + struct reftable_block header = { NULL }; + int err = 0; + uint64_t file_size = block_source_size(source); + + /* Need +1 to read type of first block. */ + uint32_t read_size = header_size(2) + 1; /* read v2 because it's larger. */ + memset(r, 0, sizeof(struct reftable_reader)); + + if (read_size > file_size) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + err = block_source_read_block(source, &header, 0, read_size); + if (err != read_size) { + err = REFTABLE_IO_ERROR; + goto done; + } + + if (memcmp(header.data, "REFT", 4)) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + r->version = header.data[4]; + if (r->version != 1 && r->version != 2) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + r->size = file_size - footer_size(r->version); + r->source = *source; + r->name = xstrdup(name); + r->hash_id = 0; + + err = block_source_read_block(source, &footer, r->size, + footer_size(r->version)); + if (err != footer_size(r->version)) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = parse_footer(r, footer.data, header.data); +done: + reftable_block_done(&footer); + reftable_block_done(&header); + return err; +} + +struct table_iter { + struct reftable_reader *r; + uint8_t typ; + uint64_t block_off; + struct block_iter bi; + int is_finished; +}; +#define TABLE_ITER_INIT \ + { \ + .bi = {.last_key = STRBUF_INIT } \ + } + +static void table_iter_copy_from(struct table_iter *dest, + struct table_iter *src) +{ + dest->r = src->r; + dest->typ = src->typ; + dest->block_off = src->block_off; + dest->is_finished = src->is_finished; + block_iter_copy_from(&dest->bi, &src->bi); +} + +static int table_iter_next_in_block(struct table_iter *ti, + struct reftable_record *rec) +{ + int res = block_iter_next(&ti->bi, rec); + if (res == 0 && reftable_record_type(rec) == BLOCK_TYPE_REF) { + rec->u.ref.update_index += ti->r->min_update_index; + } + + return res; +} + +static void table_iter_block_done(struct table_iter *ti) +{ + if (!ti->bi.br) { + return; + } + reftable_block_done(&ti->bi.br->block); + FREE_AND_NULL(ti->bi.br); + + ti->bi.last_key.len = 0; + ti->bi.next_off = 0; +} + +static int32_t extract_block_size(uint8_t *data, uint8_t *typ, uint64_t off, + int version) +{ + int32_t result = 0; + + if (off == 0) { + data += header_size(version); + } + + *typ = data[0]; + if (reftable_is_block_type(*typ)) { + result = get_be24(data + 1); + } + return result; +} + +int reader_init_block_reader(struct reftable_reader *r, struct block_reader *br, + uint64_t next_off, uint8_t want_typ) +{ + int32_t guess_block_size = r->block_size ? r->block_size : + DEFAULT_BLOCK_SIZE; + struct reftable_block block = { NULL }; + uint8_t block_typ = 0; + int err = 0; + uint32_t header_off = next_off ? 0 : header_size(r->version); + int32_t block_size = 0; + + if (next_off >= r->size) + return 1; + + err = reader_get_block(r, &block, next_off, guess_block_size); + if (err < 0) + goto done; + + block_size = extract_block_size(block.data, &block_typ, next_off, + r->version); + if (block_size < 0) { + err = block_size; + goto done; + } + if (want_typ != BLOCK_TYPE_ANY && block_typ != want_typ) { + err = 1; + goto done; + } + + if (block_size > guess_block_size) { + reftable_block_done(&block); + err = reader_get_block(r, &block, next_off, block_size); + if (err < 0) { + goto done; + } + } + + err = block_reader_init(br, &block, header_off, r->block_size, + hash_size(r->hash_id)); +done: + reftable_block_done(&block); + + return err; +} + +static int table_iter_next_block(struct table_iter *dest, + struct table_iter *src) +{ + uint64_t next_block_off = src->block_off + src->bi.br->full_block_size; + struct block_reader br = { 0 }; + int err = 0; + + dest->r = src->r; + dest->typ = src->typ; + dest->block_off = next_block_off; + + err = reader_init_block_reader(src->r, &br, next_block_off, src->typ); + if (err > 0) { + dest->is_finished = 1; + return 1; + } + if (err != 0) + return err; + else { + struct block_reader *brp = + reftable_malloc(sizeof(struct block_reader)); + *brp = br; + + dest->is_finished = 0; + block_reader_start(brp, &dest->bi); + } + return 0; +} + +static int table_iter_next(struct table_iter *ti, struct reftable_record *rec) +{ + if (reftable_record_type(rec) != ti->typ) + return REFTABLE_API_ERROR; + + while (1) { + struct table_iter next = TABLE_ITER_INIT; + int err = 0; + if (ti->is_finished) { + return 1; + } + + err = table_iter_next_in_block(ti, rec); + if (err <= 0) { + return err; + } + + err = table_iter_next_block(&next, ti); + if (err != 0) { + ti->is_finished = 1; + } + table_iter_block_done(ti); + if (err != 0) { + return err; + } + table_iter_copy_from(ti, &next); + block_iter_close(&next.bi); + } +} + +static int table_iter_next_void(void *ti, struct reftable_record *rec) +{ + return table_iter_next(ti, rec); +} + +static void table_iter_close(void *p) +{ + struct table_iter *ti = p; + table_iter_block_done(ti); + block_iter_close(&ti->bi); +} + +static struct reftable_iterator_vtable table_iter_vtable = { + .next = &table_iter_next_void, + .close = &table_iter_close, +}; + +static void iterator_from_table_iter(struct reftable_iterator *it, + struct table_iter *ti) +{ + assert(!it->ops); + it->iter_arg = ti; + it->ops = &table_iter_vtable; +} + +static int reader_table_iter_at(struct reftable_reader *r, + struct table_iter *ti, uint64_t off, + uint8_t typ) +{ + struct block_reader br = { 0 }; + struct block_reader *brp = NULL; + + int err = reader_init_block_reader(r, &br, off, typ); + if (err != 0) + return err; + + brp = reftable_malloc(sizeof(struct block_reader)); + *brp = br; + ti->r = r; + ti->typ = block_reader_type(brp); + ti->block_off = off; + block_reader_start(brp, &ti->bi); + return 0; +} + +static int reader_start(struct reftable_reader *r, struct table_iter *ti, + uint8_t typ, int index) +{ + struct reftable_reader_offsets *offs = reader_offsets_for(r, typ); + uint64_t off = offs->offset; + if (index) { + off = offs->index_offset; + if (off == 0) { + return 1; + } + typ = BLOCK_TYPE_INDEX; + } + + return reader_table_iter_at(r, ti, off, typ); +} + +static int reader_seek_linear(struct reftable_reader *r, struct table_iter *ti, + struct reftable_record *want) +{ + struct reftable_record rec = + reftable_new_record(reftable_record_type(want)); + struct strbuf want_key = STRBUF_INIT; + struct strbuf got_key = STRBUF_INIT; + struct table_iter next = TABLE_ITER_INIT; + int err = -1; + + reftable_record_key(want, &want_key); + + while (1) { + err = table_iter_next_block(&next, ti); + if (err < 0) + goto done; + + if (err > 0) { + break; + } + + err = block_reader_first_key(next.bi.br, &got_key); + if (err < 0) + goto done; + + if (strbuf_cmp(&got_key, &want_key) > 0) { + table_iter_block_done(&next); + break; + } + + table_iter_block_done(ti); + table_iter_copy_from(ti, &next); + } + + err = block_iter_seek(&ti->bi, &want_key); + if (err < 0) + goto done; + err = 0; + +done: + block_iter_close(&next.bi); + reftable_record_release(&rec); + strbuf_release(&want_key); + strbuf_release(&got_key); + return err; +} + +static int reader_seek_indexed(struct reftable_reader *r, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + struct reftable_record want_index = { + .type = BLOCK_TYPE_INDEX, .u.idx = { .last_key = STRBUF_INIT } + }; + struct reftable_record index_result = { + .type = BLOCK_TYPE_INDEX, + .u.idx = { .last_key = STRBUF_INIT }, + }; + struct table_iter index_iter = TABLE_ITER_INIT; + struct table_iter next = TABLE_ITER_INIT; + int err = 0; + + reftable_record_key(rec, &want_index.u.idx.last_key); + err = reader_start(r, &index_iter, reftable_record_type(rec), 1); + if (err < 0) + goto done; + + err = reader_seek_linear(r, &index_iter, &want_index); + while (1) { + err = table_iter_next(&index_iter, &index_result); + table_iter_block_done(&index_iter); + if (err != 0) + goto done; + + err = reader_table_iter_at(r, &next, index_result.u.idx.offset, + 0); + if (err != 0) + goto done; + + err = block_iter_seek(&next.bi, &want_index.u.idx.last_key); + if (err < 0) + goto done; + + if (next.typ == reftable_record_type(rec)) { + err = 0; + break; + } + + if (next.typ != BLOCK_TYPE_INDEX) { + err = REFTABLE_FORMAT_ERROR; + break; + } + + table_iter_copy_from(&index_iter, &next); + } + + if (err == 0) { + struct table_iter empty = TABLE_ITER_INIT; + struct table_iter *malloced = + reftable_calloc(sizeof(struct table_iter)); + *malloced = empty; + table_iter_copy_from(malloced, &next); + iterator_from_table_iter(it, malloced); + } +done: + block_iter_close(&next.bi); + table_iter_close(&index_iter); + reftable_record_release(&want_index); + reftable_record_release(&index_result); + return err; +} + +static int reader_seek_internal(struct reftable_reader *r, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + struct reftable_reader_offsets *offs = + reader_offsets_for(r, reftable_record_type(rec)); + uint64_t idx = offs->index_offset; + struct table_iter ti = TABLE_ITER_INIT; + int err = 0; + if (idx > 0) + return reader_seek_indexed(r, it, rec); + + err = reader_start(r, &ti, reftable_record_type(rec), 0); + if (err < 0) + return err; + err = reader_seek_linear(r, &ti, rec); + if (err < 0) + return err; + else { + struct table_iter *p = + reftable_malloc(sizeof(struct table_iter)); + *p = ti; + iterator_from_table_iter(it, p); + } + + return 0; +} + +static int reader_seek(struct reftable_reader *r, struct reftable_iterator *it, + struct reftable_record *rec) +{ + uint8_t typ = reftable_record_type(rec); + + struct reftable_reader_offsets *offs = reader_offsets_for(r, typ); + if (!offs->is_present) { + iterator_set_empty(it); + return 0; + } + + return reader_seek_internal(r, it, rec); +} + +int reftable_reader_seek_ref(struct reftable_reader *r, + struct reftable_iterator *it, const char *name) +{ + struct reftable_record rec = { + .type = BLOCK_TYPE_REF, + .u.ref = { + .refname = (char *)name, + }, + }; + return reader_seek(r, it, &rec); +} + +int reftable_reader_seek_log_at(struct reftable_reader *r, + struct reftable_iterator *it, const char *name, + uint64_t update_index) +{ + struct reftable_record rec = { .type = BLOCK_TYPE_LOG, + .u.log = { + .refname = (char *)name, + .update_index = update_index, + } }; + return reader_seek(r, it, &rec); +} + +int reftable_reader_seek_log(struct reftable_reader *r, + struct reftable_iterator *it, const char *name) +{ + uint64_t max = ~((uint64_t)0); + return reftable_reader_seek_log_at(r, it, name, max); +} + +void reader_close(struct reftable_reader *r) +{ + block_source_close(&r->source); + FREE_AND_NULL(r->name); +} + +int reftable_new_reader(struct reftable_reader **p, + struct reftable_block_source *src, char const *name) +{ + struct reftable_reader *rd = + reftable_calloc(sizeof(struct reftable_reader)); + int err = init_reader(rd, src, name); + if (err == 0) { + *p = rd; + } else { + block_source_close(src); + reftable_free(rd); + } + return err; +} + +void reftable_reader_free(struct reftable_reader *r) +{ + if (!r) + return; + reader_close(r); + reftable_free(r); +} + +static int reftable_reader_refs_for_indexed(struct reftable_reader *r, + struct reftable_iterator *it, + uint8_t *oid) +{ + struct reftable_record want = { + .type = BLOCK_TYPE_OBJ, + .u.obj = { + .hash_prefix = oid, + .hash_prefix_len = r->object_id_len, + }, + }; + struct reftable_iterator oit = { NULL }; + struct reftable_record got = { + .type = BLOCK_TYPE_OBJ, + .u.obj = { 0 }, + }; + int err = 0; + struct indexed_table_ref_iter *itr = NULL; + + /* Look through the reverse index. */ + err = reader_seek(r, &oit, &want); + if (err != 0) + goto done; + + /* read out the reftable_obj_record */ + err = iterator_next(&oit, &got); + if (err < 0) + goto done; + + if (err > 0 || memcmp(want.u.obj.hash_prefix, got.u.obj.hash_prefix, + r->object_id_len)) { + /* didn't find it; return empty iterator */ + iterator_set_empty(it); + err = 0; + goto done; + } + + err = new_indexed_table_ref_iter(&itr, r, oid, hash_size(r->hash_id), + got.u.obj.offsets, + got.u.obj.offset_len); + if (err < 0) + goto done; + got.u.obj.offsets = NULL; + iterator_from_indexed_table_ref_iter(it, itr); + +done: + reftable_iterator_destroy(&oit); + reftable_record_release(&got); + return err; +} + +static int reftable_reader_refs_for_unindexed(struct reftable_reader *r, + struct reftable_iterator *it, + uint8_t *oid) +{ + struct table_iter ti_empty = TABLE_ITER_INIT; + struct table_iter *ti = reftable_calloc(sizeof(struct table_iter)); + struct filtering_ref_iterator *filter = NULL; + struct filtering_ref_iterator empty = FILTERING_REF_ITERATOR_INIT; + int oid_len = hash_size(r->hash_id); + int err; + + *ti = ti_empty; + err = reader_start(r, ti, BLOCK_TYPE_REF, 0); + if (err < 0) { + reftable_free(ti); + return err; + } + + filter = reftable_malloc(sizeof(struct filtering_ref_iterator)); + *filter = empty; + + strbuf_add(&filter->oid, oid, oid_len); + reftable_table_from_reader(&filter->tab, r); + filter->double_check = 0; + iterator_from_table_iter(&filter->it, ti); + + iterator_from_filtering_ref_iterator(it, filter); + return 0; +} + +int reftable_reader_refs_for(struct reftable_reader *r, + struct reftable_iterator *it, uint8_t *oid) +{ + if (r->obj_offsets.is_present) + return reftable_reader_refs_for_indexed(r, it, oid); + return reftable_reader_refs_for_unindexed(r, it, oid); +} + +uint64_t reftable_reader_max_update_index(struct reftable_reader *r) +{ + return r->max_update_index; +} + +uint64_t reftable_reader_min_update_index(struct reftable_reader *r) +{ + return r->min_update_index; +} + +/* generic table interface. */ + +static int reftable_reader_seek_void(void *tab, struct reftable_iterator *it, + struct reftable_record *rec) +{ + return reader_seek(tab, it, rec); +} + +static uint32_t reftable_reader_hash_id_void(void *tab) +{ + return reftable_reader_hash_id(tab); +} + +static uint64_t reftable_reader_min_update_index_void(void *tab) +{ + return reftable_reader_min_update_index(tab); +} + +static uint64_t reftable_reader_max_update_index_void(void *tab) +{ + return reftable_reader_max_update_index(tab); +} + +static struct reftable_table_vtable reader_vtable = { + .seek_record = reftable_reader_seek_void, + .hash_id = reftable_reader_hash_id_void, + .min_update_index = reftable_reader_min_update_index_void, + .max_update_index = reftable_reader_max_update_index_void, +}; + +void reftable_table_from_reader(struct reftable_table *tab, + struct reftable_reader *reader) +{ + assert(!tab->ops); + tab->ops = &reader_vtable; + tab->table_arg = reader; +} + + +int reftable_reader_print_file(const char *tablename) +{ + struct reftable_block_source src = { NULL }; + int err = reftable_block_source_from_file(&src, tablename); + struct reftable_reader *r = NULL; + struct reftable_table tab = { NULL }; + if (err < 0) + goto done; + + err = reftable_new_reader(&r, &src, tablename); + if (err < 0) + goto done; + + reftable_table_from_reader(&tab, r); + err = reftable_table_print(&tab); +done: + reftable_reader_free(r); + return err; +} diff --git a/reftable/reader.h b/reftable/reader.h new file mode 100644 index 0000000000..e869165f23 --- /dev/null +++ b/reftable/reader.h @@ -0,0 +1,64 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef READER_H +#define READER_H + +#include "block.h" +#include "record.h" +#include "reftable-iterator.h" +#include "reftable-reader.h" + +uint64_t block_source_size(struct reftable_block_source *source); + +int block_source_read_block(struct reftable_block_source *source, + struct reftable_block *dest, uint64_t off, + uint32_t size); +void block_source_close(struct reftable_block_source *source); + +/* metadata for a block type */ +struct reftable_reader_offsets { + int is_present; + uint64_t offset; + uint64_t index_offset; +}; + +/* The state for reading a reftable file. */ +struct reftable_reader { + /* for convience, associate a name with the instance. */ + char *name; + struct reftable_block_source source; + + /* Size of the file, excluding the footer. */ + uint64_t size; + + /* 'sha1' for SHA1, 's256' for SHA-256 */ + uint32_t hash_id; + + uint32_t block_size; + uint64_t min_update_index; + uint64_t max_update_index; + /* Length of the OID keys in the 'o' section */ + int object_id_len; + int version; + + struct reftable_reader_offsets ref_offsets; + struct reftable_reader_offsets obj_offsets; + struct reftable_reader_offsets log_offsets; +}; + +int init_reader(struct reftable_reader *r, struct reftable_block_source *source, + const char *name); +void reader_close(struct reftable_reader *r); +const char *reader_name(struct reftable_reader *r); + +/* initialize a block reader to read from `r` */ +int reader_init_block_reader(struct reftable_reader *r, struct block_reader *br, + uint64_t next_off, uint8_t want_typ); + +#endif diff --git a/reftable/readwrite_test.c b/reftable/readwrite_test.c new file mode 100644 index 0000000000..469ab79a5a --- /dev/null +++ b/reftable/readwrite_test.c @@ -0,0 +1,851 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" + +#include "basics.h" +#include "block.h" +#include "blocksource.h" +#include "constants.h" +#include "reader.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-tests.h" +#include "reftable-writer.h" + +static const int update_index = 5; + +static void test_buffer(void) +{ + struct strbuf buf = STRBUF_INIT; + struct reftable_block_source source = { NULL }; + struct reftable_block out = { NULL }; + int n; + uint8_t in[] = "hello"; + strbuf_add(&buf, in, sizeof(in)); + block_source_from_strbuf(&source, &buf); + EXPECT(block_source_size(&source) == 6); + n = block_source_read_block(&source, &out, 0, sizeof(in)); + EXPECT(n == sizeof(in)); + EXPECT(!memcmp(in, out.data, n)); + reftable_block_done(&out); + + n = block_source_read_block(&source, &out, 1, 2); + EXPECT(n == 2); + EXPECT(!memcmp(out.data, "el", 2)); + + reftable_block_done(&out); + block_source_close(&source); + strbuf_release(&buf); +} + +static void write_table(char ***names, struct strbuf *buf, int N, + int block_size, uint32_t hash_id) +{ + struct reftable_write_options opts = { + .block_size = block_size, + .hash_id = hash_id, + }; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, buf, &opts); + struct reftable_ref_record ref = { NULL }; + int i = 0, n; + struct reftable_log_record log = { NULL }; + const struct reftable_stats *stats = NULL; + *names = reftable_calloc(sizeof(char *) * (N + 1)); + reftable_writer_set_limits(w, update_index, update_index); + for (i = 0; i < N; i++) { + uint8_t hash[GIT_SHA256_RAWSZ] = { 0 }; + char name[100]; + int n; + + set_test_hash(hash, i); + + snprintf(name, sizeof(name), "refs/heads/branch%02d", i); + + ref.refname = name; + ref.update_index = update_index; + ref.value_type = REFTABLE_REF_VAL1; + ref.value.val1 = hash; + (*names)[i] = xstrdup(name); + + n = reftable_writer_add_ref(w, &ref); + EXPECT(n == 0); + } + + for (i = 0; i < N; i++) { + uint8_t hash[GIT_SHA256_RAWSZ] = { 0 }; + char name[100]; + int n; + + set_test_hash(hash, i); + + snprintf(name, sizeof(name), "refs/heads/branch%02d", i); + + log.refname = name; + log.update_index = update_index; + log.value_type = REFTABLE_LOG_UPDATE; + log.value.update.new_hash = hash; + log.value.update.message = "message"; + + n = reftable_writer_add_log(w, &log); + EXPECT(n == 0); + } + + n = reftable_writer_close(w); + EXPECT(n == 0); + + stats = reftable_writer_stats(w); + for (i = 0; i < stats->ref_stats.blocks; i++) { + int off = i * opts.block_size; + if (off == 0) { + off = header_size( + (hash_id == GIT_SHA256_FORMAT_ID) ? 2 : 1); + } + EXPECT(buf->buf[off] == 'r'); + } + + EXPECT(stats->log_stats.blocks > 0); + reftable_writer_free(w); +} + +static void test_log_buffer_size(void) +{ + struct strbuf buf = STRBUF_INIT; + struct reftable_write_options opts = { + .block_size = 4096, + }; + int err; + int i; + struct reftable_log_record + log = { .refname = "refs/heads/master", + .update_index = 0xa, + .value_type = REFTABLE_LOG_UPDATE, + .value = { .update = { + .name = "Han-Wen Nienhuys", + .email = "hanwen@google.com", + .tz_offset = 100, + .time = 0x5e430672, + .message = "commit: 9\n", + } } }; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + /* This tests buffer extension for log compression. Must use a random + hash, to ensure that the compressed part is larger than the original. + */ + uint8_t hash1[GIT_SHA1_RAWSZ], hash2[GIT_SHA1_RAWSZ]; + for (i = 0; i < GIT_SHA1_RAWSZ; i++) { + hash1[i] = (uint8_t)(rand() % 256); + hash2[i] = (uint8_t)(rand() % 256); + } + log.value.update.old_hash = hash1; + log.value.update.new_hash = hash2; + reftable_writer_set_limits(w, update_index, update_index); + err = reftable_writer_add_log(w, &log); + EXPECT_ERR(err); + err = reftable_writer_close(w); + EXPECT_ERR(err); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_log_overflow(void) +{ + struct strbuf buf = STRBUF_INIT; + char msg[256] = { 0 }; + struct reftable_write_options opts = { + .block_size = ARRAY_SIZE(msg), + }; + int err; + struct reftable_log_record + log = { .refname = "refs/heads/master", + .update_index = 0xa, + .value_type = REFTABLE_LOG_UPDATE, + .value = { .update = { + .name = "Han-Wen Nienhuys", + .email = "hanwen@google.com", + .tz_offset = 100, + .time = 0x5e430672, + .message = msg, + } } }; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + uint8_t hash1[GIT_SHA1_RAWSZ] = {1}, hash2[GIT_SHA1_RAWSZ] = { 2 }; + + memset(msg, 'x', sizeof(msg) - 1); + log.value.update.old_hash = hash1; + log.value.update.new_hash = hash2; + reftable_writer_set_limits(w, update_index, update_index); + err = reftable_writer_add_log(w, &log); + EXPECT(err == REFTABLE_ENTRY_TOO_BIG_ERROR); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_log_write_read(void) +{ + int N = 2; + char **names = reftable_calloc(sizeof(char *) * (N + 1)); + int err; + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_ref_record ref = { NULL }; + int i = 0; + struct reftable_log_record log = { NULL }; + int n; + struct reftable_iterator it = { NULL }; + struct reftable_reader rd = { NULL }; + struct reftable_block_source source = { NULL }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + const struct reftable_stats *stats = NULL; + reftable_writer_set_limits(w, 0, N); + for (i = 0; i < N; i++) { + char name[256]; + struct reftable_ref_record ref = { NULL }; + snprintf(name, sizeof(name), "b%02d%0*d", i, 130, 7); + names[i] = xstrdup(name); + ref.refname = name; + ref.update_index = i; + + err = reftable_writer_add_ref(w, &ref); + EXPECT_ERR(err); + } + for (i = 0; i < N; i++) { + uint8_t hash1[GIT_SHA1_RAWSZ], hash2[GIT_SHA1_RAWSZ]; + struct reftable_log_record log = { NULL }; + set_test_hash(hash1, i); + set_test_hash(hash2, i + 1); + + log.refname = names[i]; + log.update_index = i; + log.value_type = REFTABLE_LOG_UPDATE; + log.value.update.old_hash = hash1; + log.value.update.new_hash = hash2; + + err = reftable_writer_add_log(w, &log); + EXPECT_ERR(err); + } + + n = reftable_writer_close(w); + EXPECT(n == 0); + + stats = reftable_writer_stats(w); + EXPECT(stats->log_stats.blocks > 0); + reftable_writer_free(w); + w = NULL; + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.log"); + EXPECT_ERR(err); + + err = reftable_reader_seek_ref(&rd, &it, names[N - 1]); + EXPECT_ERR(err); + + err = reftable_iterator_next_ref(&it, &ref); + EXPECT_ERR(err); + + /* end of iteration. */ + err = reftable_iterator_next_ref(&it, &ref); + EXPECT(0 < err); + + reftable_iterator_destroy(&it); + reftable_ref_record_release(&ref); + + err = reftable_reader_seek_log(&rd, &it, ""); + EXPECT_ERR(err); + + i = 0; + while (1) { + int err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + break; + } + + EXPECT_ERR(err); + EXPECT_STREQ(names[i], log.refname); + EXPECT(i == log.update_index); + i++; + reftable_log_record_release(&log); + } + + EXPECT(i == N); + reftable_iterator_destroy(&it); + + /* cleanup. */ + strbuf_release(&buf); + free_names(names); + reader_close(&rd); +} + +static void test_log_zlib_corruption(void) +{ + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_iterator it = { 0 }; + struct reftable_reader rd = { 0 }; + struct reftable_block_source source = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + const struct reftable_stats *stats = NULL; + uint8_t hash1[GIT_SHA1_RAWSZ] = { 1 }; + uint8_t hash2[GIT_SHA1_RAWSZ] = { 2 }; + char message[100] = { 0 }; + int err, i, n; + + struct reftable_log_record log = { + .refname = "refname", + .value_type = REFTABLE_LOG_UPDATE, + .value = { + .update = { + .new_hash = hash1, + .old_hash = hash2, + .name = "My Name", + .email = "myname@invalid", + .message = message, + }, + }, + }; + + for (i = 0; i < sizeof(message) - 1; i++) + message[i] = (uint8_t)(rand() % 64 + ' '); + + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_add_log(w, &log); + EXPECT_ERR(err); + + n = reftable_writer_close(w); + EXPECT(n == 0); + + stats = reftable_writer_stats(w); + EXPECT(stats->log_stats.blocks > 0); + reftable_writer_free(w); + w = NULL; + + /* corrupt the data. */ + buf.buf[50] ^= 0x99; + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.log"); + EXPECT_ERR(err); + + err = reftable_reader_seek_log(&rd, &it, "refname"); + EXPECT(err == REFTABLE_ZLIB_ERROR); + + reftable_iterator_destroy(&it); + + /* cleanup. */ + strbuf_release(&buf); + reader_close(&rd); +} + +static void test_table_read_write_sequential(void) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 50; + struct reftable_iterator it = { NULL }; + struct reftable_block_source source = { NULL }; + struct reftable_reader rd = { NULL }; + int err = 0; + int j = 0; + + write_table(&names, &buf, N, 256, GIT_SHA1_FORMAT_ID); + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + EXPECT_ERR(err); + + err = reftable_reader_seek_ref(&rd, &it, ""); + EXPECT_ERR(err); + + while (1) { + struct reftable_ref_record ref = { NULL }; + int r = reftable_iterator_next_ref(&it, &ref); + EXPECT(r >= 0); + if (r > 0) { + break; + } + EXPECT(0 == strcmp(names[j], ref.refname)); + EXPECT(update_index == ref.update_index); + + j++; + reftable_ref_record_release(&ref); + } + EXPECT(j == N); + reftable_iterator_destroy(&it); + strbuf_release(&buf); + free_names(names); + + reader_close(&rd); +} + +static void test_table_write_small_table(void) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 1; + write_table(&names, &buf, N, 4096, GIT_SHA1_FORMAT_ID); + EXPECT(buf.len < 200); + strbuf_release(&buf); + free_names(names); +} + +static void test_table_read_api(void) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 50; + struct reftable_reader rd = { NULL }; + struct reftable_block_source source = { NULL }; + int err; + int i; + struct reftable_log_record log = { NULL }; + struct reftable_iterator it = { NULL }; + + write_table(&names, &buf, N, 256, GIT_SHA1_FORMAT_ID); + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + EXPECT_ERR(err); + + err = reftable_reader_seek_ref(&rd, &it, names[0]); + EXPECT_ERR(err); + + err = reftable_iterator_next_log(&it, &log); + EXPECT(err == REFTABLE_API_ERROR); + + strbuf_release(&buf); + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } + reftable_iterator_destroy(&it); + reftable_free(names); + reader_close(&rd); + strbuf_release(&buf); +} + +static void test_table_read_write_seek(int index, int hash_id) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 50; + struct reftable_reader rd = { NULL }; + struct reftable_block_source source = { NULL }; + int err; + int i = 0; + + struct reftable_iterator it = { NULL }; + struct strbuf pastLast = STRBUF_INIT; + struct reftable_ref_record ref = { NULL }; + + write_table(&names, &buf, N, 256, hash_id); + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + EXPECT_ERR(err); + EXPECT(hash_id == reftable_reader_hash_id(&rd)); + + if (!index) { + rd.ref_offsets.index_offset = 0; + } else { + EXPECT(rd.ref_offsets.index_offset > 0); + } + + for (i = 1; i < N; i++) { + int err = reftable_reader_seek_ref(&rd, &it, names[i]); + EXPECT_ERR(err); + err = reftable_iterator_next_ref(&it, &ref); + EXPECT_ERR(err); + EXPECT(0 == strcmp(names[i], ref.refname)); + EXPECT(REFTABLE_REF_VAL1 == ref.value_type); + EXPECT(i == ref.value.val1[0]); + + reftable_ref_record_release(&ref); + reftable_iterator_destroy(&it); + } + + strbuf_addstr(&pastLast, names[N - 1]); + strbuf_addstr(&pastLast, "/"); + + err = reftable_reader_seek_ref(&rd, &it, pastLast.buf); + if (err == 0) { + struct reftable_ref_record ref = { NULL }; + int err = reftable_iterator_next_ref(&it, &ref); + EXPECT(err > 0); + } else { + EXPECT(err > 0); + } + + strbuf_release(&pastLast); + reftable_iterator_destroy(&it); + + strbuf_release(&buf); + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } + reftable_free(names); + reader_close(&rd); +} + +static void test_table_read_write_seek_linear(void) +{ + test_table_read_write_seek(0, GIT_SHA1_FORMAT_ID); +} + +static void test_table_read_write_seek_linear_sha256(void) +{ + test_table_read_write_seek(0, GIT_SHA256_FORMAT_ID); +} + +static void test_table_read_write_seek_index(void) +{ + test_table_read_write_seek(1, GIT_SHA1_FORMAT_ID); +} + +static void test_table_refs_for(int indexed) +{ + int N = 50; + char **want_names = reftable_calloc(sizeof(char *) * (N + 1)); + int want_names_len = 0; + uint8_t want_hash[GIT_SHA1_RAWSZ]; + + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_ref_record ref = { NULL }; + int i = 0; + int n; + int err; + struct reftable_reader rd; + struct reftable_block_source source = { NULL }; + + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + struct reftable_iterator it = { NULL }; + int j; + + set_test_hash(want_hash, 4); + + for (i = 0; i < N; i++) { + uint8_t hash[GIT_SHA1_RAWSZ]; + char fill[51] = { 0 }; + char name[100]; + uint8_t hash1[GIT_SHA1_RAWSZ]; + uint8_t hash2[GIT_SHA1_RAWSZ]; + struct reftable_ref_record ref = { NULL }; + + memset(hash, i, sizeof(hash)); + memset(fill, 'x', 50); + /* Put the variable part in the start */ + snprintf(name, sizeof(name), "br%02d%s", i, fill); + name[40] = 0; + ref.refname = name; + + set_test_hash(hash1, i / 4); + set_test_hash(hash2, 3 + i / 4); + ref.value_type = REFTABLE_REF_VAL2; + ref.value.val2.value = hash1; + ref.value.val2.target_value = hash2; + + /* 80 bytes / entry, so 3 entries per block. Yields 17 + */ + /* blocks. */ + n = reftable_writer_add_ref(w, &ref); + EXPECT(n == 0); + + if (!memcmp(hash1, want_hash, GIT_SHA1_RAWSZ) || + !memcmp(hash2, want_hash, GIT_SHA1_RAWSZ)) { + want_names[want_names_len++] = xstrdup(name); + } + } + + n = reftable_writer_close(w); + EXPECT(n == 0); + + reftable_writer_free(w); + w = NULL; + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + EXPECT_ERR(err); + if (!indexed) { + rd.obj_offsets.is_present = 0; + } + + err = reftable_reader_seek_ref(&rd, &it, ""); + EXPECT_ERR(err); + reftable_iterator_destroy(&it); + + err = reftable_reader_refs_for(&rd, &it, want_hash); + EXPECT_ERR(err); + + j = 0; + while (1) { + int err = reftable_iterator_next_ref(&it, &ref); + EXPECT(err >= 0); + if (err > 0) { + break; + } + + EXPECT(j < want_names_len); + EXPECT(0 == strcmp(ref.refname, want_names[j])); + j++; + reftable_ref_record_release(&ref); + } + EXPECT(j == want_names_len); + + strbuf_release(&buf); + free_names(want_names); + reftable_iterator_destroy(&it); + reader_close(&rd); +} + +static void test_table_refs_for_no_index(void) +{ + test_table_refs_for(0); +} + +static void test_table_refs_for_obj_index(void) +{ + test_table_refs_for(1); +} + +static void test_write_empty_table(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + struct reftable_block_source source = { NULL }; + struct reftable_reader *rd = NULL; + struct reftable_ref_record rec = { NULL }; + struct reftable_iterator it = { NULL }; + int err; + + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_close(w); + EXPECT(err == REFTABLE_EMPTY_TABLE_ERROR); + reftable_writer_free(w); + + EXPECT(buf.len == header_size(1) + footer_size(1)); + + block_source_from_strbuf(&source, &buf); + + err = reftable_new_reader(&rd, &source, "filename"); + EXPECT_ERR(err); + + err = reftable_reader_seek_ref(rd, &it, ""); + EXPECT_ERR(err); + + err = reftable_iterator_next_ref(&it, &rec); + EXPECT(err > 0); + + reftable_iterator_destroy(&it); + reftable_reader_free(rd); + strbuf_release(&buf); +} + +static void test_write_object_id_min_length(void) +{ + struct reftable_write_options opts = { + .block_size = 75, + }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + uint8_t hash[GIT_SHA1_RAWSZ] = {42}; + struct reftable_ref_record ref = { + .update_index = 1, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash, + }; + int err; + int i; + + reftable_writer_set_limits(w, 1, 1); + + /* Write the same hash in many refs. If there is only 1 hash, the + * disambiguating prefix is length 0 */ + for (i = 0; i < 256; i++) { + char name[256]; + snprintf(name, sizeof(name), "ref%05d", i); + ref.refname = name; + err = reftable_writer_add_ref(w, &ref); + EXPECT_ERR(err); + } + + err = reftable_writer_close(w); + EXPECT_ERR(err); + EXPECT(reftable_writer_stats(w)->object_id_len == 2); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_write_object_id_length(void) +{ + struct reftable_write_options opts = { + .block_size = 75, + }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + uint8_t hash[GIT_SHA1_RAWSZ] = {42}; + struct reftable_ref_record ref = { + .update_index = 1, + .value_type = REFTABLE_REF_VAL1, + .value.val1 = hash, + }; + int err; + int i; + + reftable_writer_set_limits(w, 1, 1); + + /* Write the same hash in many refs. If there is only 1 hash, the + * disambiguating prefix is length 0 */ + for (i = 0; i < 256; i++) { + char name[256]; + snprintf(name, sizeof(name), "ref%05d", i); + ref.refname = name; + ref.value.val1[15] = i; + err = reftable_writer_add_ref(w, &ref); + EXPECT_ERR(err); + } + + err = reftable_writer_close(w); + EXPECT_ERR(err); + EXPECT(reftable_writer_stats(w)->object_id_len == 16); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_write_empty_key(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + struct reftable_ref_record ref = { + .refname = "", + .update_index = 1, + .value_type = REFTABLE_REF_DELETION, + }; + int err; + + reftable_writer_set_limits(w, 1, 1); + err = reftable_writer_add_ref(w, &ref); + EXPECT(err == REFTABLE_API_ERROR); + + err = reftable_writer_close(w); + EXPECT(err == REFTABLE_EMPTY_TABLE_ERROR); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_write_key_order(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + struct reftable_ref_record refs[2] = { + { + .refname = "b", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value = { + .symref = "target", + }, + }, { + .refname = "a", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value = { + .symref = "target", + }, + } + }; + int err; + + reftable_writer_set_limits(w, 1, 1); + err = reftable_writer_add_ref(w, &refs[0]); + EXPECT_ERR(err); + err = reftable_writer_add_ref(w, &refs[1]); + EXPECT(err == REFTABLE_API_ERROR); + reftable_writer_close(w); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_corrupt_table_empty(void) +{ + struct strbuf buf = STRBUF_INIT; + struct reftable_block_source source = { NULL }; + struct reftable_reader rd = { NULL }; + int err; + + block_source_from_strbuf(&source, &buf); + err = init_reader(&rd, &source, "file.log"); + EXPECT(err == REFTABLE_FORMAT_ERROR); +} + +static void test_corrupt_table(void) +{ + uint8_t zeros[1024] = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_block_source source = { NULL }; + struct reftable_reader rd = { NULL }; + int err; + strbuf_add(&buf, zeros, sizeof(zeros)); + + block_source_from_strbuf(&source, &buf); + err = init_reader(&rd, &source, "file.log"); + EXPECT(err == REFTABLE_FORMAT_ERROR); + strbuf_release(&buf); +} + +int readwrite_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_log_zlib_corruption); + RUN_TEST(test_corrupt_table); + RUN_TEST(test_corrupt_table_empty); + RUN_TEST(test_log_write_read); + RUN_TEST(test_write_key_order); + RUN_TEST(test_table_read_write_seek_linear_sha256); + RUN_TEST(test_log_buffer_size); + RUN_TEST(test_table_write_small_table); + RUN_TEST(test_buffer); + RUN_TEST(test_table_read_api); + RUN_TEST(test_table_read_write_sequential); + RUN_TEST(test_table_read_write_seek_linear); + RUN_TEST(test_table_read_write_seek_index); + RUN_TEST(test_table_refs_for_no_index); + RUN_TEST(test_table_refs_for_obj_index); + RUN_TEST(test_write_empty_key); + RUN_TEST(test_write_empty_table); + RUN_TEST(test_log_overflow); + RUN_TEST(test_write_object_id_length); + RUN_TEST(test_write_object_id_min_length); + return 0; +} diff --git a/reftable/record.c b/reftable/record.c new file mode 100644 index 0000000000..fbaa1fbef5 --- /dev/null +++ b/reftable/record.c @@ -0,0 +1,1314 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +/* record.c - methods for different types of records. */ + +#include "record.h" + +#include "system.h" +#include "constants.h" +#include "reftable-error.h" +#include "basics.h" + +static struct reftable_record_vtable * +reftable_record_vtable(struct reftable_record *rec); +static void *reftable_record_data(struct reftable_record *rec); + +int get_var_int(uint64_t *dest, struct string_view *in) +{ + int ptr = 0; + uint64_t val; + + if (in->len == 0) + return -1; + val = in->buf[ptr] & 0x7f; + + while (in->buf[ptr] & 0x80) { + ptr++; + if (ptr > in->len) { + return -1; + } + val = (val + 1) << 7 | (uint64_t)(in->buf[ptr] & 0x7f); + } + + *dest = val; + return ptr + 1; +} + +int put_var_int(struct string_view *dest, uint64_t val) +{ + uint8_t buf[10] = { 0 }; + int i = 9; + int n = 0; + buf[i] = (uint8_t)(val & 0x7f); + i--; + while (1) { + val >>= 7; + if (!val) { + break; + } + val--; + buf[i] = 0x80 | (uint8_t)(val & 0x7f); + i--; + } + + n = sizeof(buf) - i - 1; + if (dest->len < n) + return -1; + memcpy(dest->buf, &buf[i + 1], n); + return n; +} + +int reftable_is_block_type(uint8_t typ) +{ + switch (typ) { + case BLOCK_TYPE_REF: + case BLOCK_TYPE_LOG: + case BLOCK_TYPE_OBJ: + case BLOCK_TYPE_INDEX: + return 1; + } + return 0; +} + +uint8_t *reftable_ref_record_val1(const struct reftable_ref_record *rec) +{ + switch (rec->value_type) { + case REFTABLE_REF_VAL1: + return rec->value.val1; + case REFTABLE_REF_VAL2: + return rec->value.val2.value; + default: + return NULL; + } +} + +uint8_t *reftable_ref_record_val2(const struct reftable_ref_record *rec) +{ + switch (rec->value_type) { + case REFTABLE_REF_VAL2: + return rec->value.val2.target_value; + default: + return NULL; + } +} + +static int decode_string(struct strbuf *dest, struct string_view in) +{ + int start_len = in.len; + uint64_t tsize = 0; + int n = get_var_int(&tsize, &in); + if (n <= 0) + return -1; + string_view_consume(&in, n); + if (in.len < tsize) + return -1; + + strbuf_reset(dest); + strbuf_add(dest, in.buf, tsize); + string_view_consume(&in, tsize); + + return start_len - in.len; +} + +static int encode_string(char *str, struct string_view s) +{ + struct string_view start = s; + int l = strlen(str); + int n = put_var_int(&s, l); + if (n < 0) + return -1; + string_view_consume(&s, n); + if (s.len < l) + return -1; + memcpy(s.buf, str, l); + string_view_consume(&s, l); + + return start.len - s.len; +} + +int reftable_encode_key(int *restart, struct string_view dest, + struct strbuf prev_key, struct strbuf key, + uint8_t extra) +{ + struct string_view start = dest; + int prefix_len = common_prefix_size(&prev_key, &key); + uint64_t suffix_len = key.len - prefix_len; + int n = put_var_int(&dest, (uint64_t)prefix_len); + if (n < 0) + return -1; + string_view_consume(&dest, n); + + *restart = (prefix_len == 0); + + n = put_var_int(&dest, suffix_len << 3 | (uint64_t)extra); + if (n < 0) + return -1; + string_view_consume(&dest, n); + + if (dest.len < suffix_len) + return -1; + memcpy(dest.buf, key.buf + prefix_len, suffix_len); + string_view_consume(&dest, suffix_len); + + return start.len - dest.len; +} + +int reftable_decode_key(struct strbuf *key, uint8_t *extra, + struct strbuf last_key, struct string_view in) +{ + int start_len = in.len; + uint64_t prefix_len = 0; + uint64_t suffix_len = 0; + int n = get_var_int(&prefix_len, &in); + if (n < 0) + return -1; + string_view_consume(&in, n); + + if (prefix_len > last_key.len) + return -1; + + n = get_var_int(&suffix_len, &in); + if (n <= 0) + return -1; + string_view_consume(&in, n); + + *extra = (uint8_t)(suffix_len & 0x7); + suffix_len >>= 3; + + if (in.len < suffix_len) + return -1; + + strbuf_reset(key); + strbuf_add(key, last_key.buf, prefix_len); + strbuf_add(key, in.buf, suffix_len); + string_view_consume(&in, suffix_len); + + return start_len - in.len; +} + +static void reftable_ref_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_ref_record *rec = + (const struct reftable_ref_record *)r; + strbuf_reset(dest); + strbuf_addstr(dest, rec->refname); +} + +static void reftable_ref_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_ref_record *ref = rec; + const struct reftable_ref_record *src = src_rec; + assert(hash_size > 0); + + /* This is simple and correct, but we could probably reuse the hash + * fields. */ + reftable_ref_record_release(ref); + if (src->refname) { + ref->refname = xstrdup(src->refname); + } + ref->update_index = src->update_index; + ref->value_type = src->value_type; + switch (src->value_type) { + case REFTABLE_REF_DELETION: + break; + case REFTABLE_REF_VAL1: + ref->value.val1 = reftable_malloc(hash_size); + memcpy(ref->value.val1, src->value.val1, hash_size); + break; + case REFTABLE_REF_VAL2: + ref->value.val2.value = reftable_malloc(hash_size); + memcpy(ref->value.val2.value, src->value.val2.value, hash_size); + ref->value.val2.target_value = reftable_malloc(hash_size); + memcpy(ref->value.val2.target_value, + src->value.val2.target_value, hash_size); + break; + case REFTABLE_REF_SYMREF: + ref->value.symref = xstrdup(src->value.symref); + break; + } +} + +static char hexdigit(int c) +{ + if (c <= 9) + return '0' + c; + return 'a' + (c - 10); +} + +static void hex_format(char *dest, uint8_t *src, int hash_size) +{ + assert(hash_size > 0); + if (src) { + int i = 0; + for (i = 0; i < hash_size; i++) { + dest[2 * i] = hexdigit(src[i] >> 4); + dest[2 * i + 1] = hexdigit(src[i] & 0xf); + } + dest[2 * hash_size] = 0; + } +} + +static void reftable_ref_record_print_sz(const struct reftable_ref_record *ref, + int hash_size) +{ + char hex[GIT_MAX_HEXSZ + 1] = { 0 }; /* BUG */ + printf("ref{%s(%" PRIu64 ") ", ref->refname, ref->update_index); + switch (ref->value_type) { + case REFTABLE_REF_SYMREF: + printf("=> %s", ref->value.symref); + break; + case REFTABLE_REF_VAL2: + hex_format(hex, ref->value.val2.value, hash_size); + printf("val 2 %s", hex); + hex_format(hex, ref->value.val2.target_value, + hash_size); + printf("(T %s)", hex); + break; + case REFTABLE_REF_VAL1: + hex_format(hex, ref->value.val1, hash_size); + printf("val 1 %s", hex); + break; + case REFTABLE_REF_DELETION: + printf("delete"); + break; + } + printf("}\n"); +} + +void reftable_ref_record_print(const struct reftable_ref_record *ref, + uint32_t hash_id) { + reftable_ref_record_print_sz(ref, hash_size(hash_id)); +} + +static void reftable_ref_record_release_void(void *rec) +{ + reftable_ref_record_release(rec); +} + +void reftable_ref_record_release(struct reftable_ref_record *ref) +{ + switch (ref->value_type) { + case REFTABLE_REF_SYMREF: + reftable_free(ref->value.symref); + break; + case REFTABLE_REF_VAL2: + reftable_free(ref->value.val2.target_value); + reftable_free(ref->value.val2.value); + break; + case REFTABLE_REF_VAL1: + reftable_free(ref->value.val1); + break; + case REFTABLE_REF_DELETION: + break; + default: + abort(); + } + + reftable_free(ref->refname); + memset(ref, 0, sizeof(struct reftable_ref_record)); +} + +static uint8_t reftable_ref_record_val_type(const void *rec) +{ + const struct reftable_ref_record *r = + (const struct reftable_ref_record *)rec; + return r->value_type; +} + +static int reftable_ref_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + const struct reftable_ref_record *r = + (const struct reftable_ref_record *)rec; + struct string_view start = s; + int n = put_var_int(&s, r->update_index); + assert(hash_size > 0); + if (n < 0) + return -1; + string_view_consume(&s, n); + + switch (r->value_type) { + case REFTABLE_REF_SYMREF: + n = encode_string(r->value.symref, s); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + break; + case REFTABLE_REF_VAL2: + if (s.len < 2 * hash_size) { + return -1; + } + memcpy(s.buf, r->value.val2.value, hash_size); + string_view_consume(&s, hash_size); + memcpy(s.buf, r->value.val2.target_value, hash_size); + string_view_consume(&s, hash_size); + break; + case REFTABLE_REF_VAL1: + if (s.len < hash_size) { + return -1; + } + memcpy(s.buf, r->value.val1, hash_size); + string_view_consume(&s, hash_size); + break; + case REFTABLE_REF_DELETION: + break; + default: + abort(); + } + + return start.len - s.len; +} + +static int reftable_ref_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct reftable_ref_record *r = rec; + struct string_view start = in; + uint64_t update_index = 0; + int n = get_var_int(&update_index, &in); + if (n < 0) + return n; + string_view_consume(&in, n); + + reftable_ref_record_release(r); + + assert(hash_size > 0); + + r->refname = reftable_realloc(r->refname, key.len + 1); + memcpy(r->refname, key.buf, key.len); + r->update_index = update_index; + r->refname[key.len] = 0; + r->value_type = val_type; + switch (val_type) { + case REFTABLE_REF_VAL1: + if (in.len < hash_size) { + return -1; + } + + r->value.val1 = reftable_malloc(hash_size); + memcpy(r->value.val1, in.buf, hash_size); + string_view_consume(&in, hash_size); + break; + + case REFTABLE_REF_VAL2: + if (in.len < 2 * hash_size) { + return -1; + } + + r->value.val2.value = reftable_malloc(hash_size); + memcpy(r->value.val2.value, in.buf, hash_size); + string_view_consume(&in, hash_size); + + r->value.val2.target_value = reftable_malloc(hash_size); + memcpy(r->value.val2.target_value, in.buf, hash_size); + string_view_consume(&in, hash_size); + break; + + case REFTABLE_REF_SYMREF: { + struct strbuf dest = STRBUF_INIT; + int n = decode_string(&dest, in); + if (n < 0) { + return -1; + } + string_view_consume(&in, n); + r->value.symref = dest.buf; + } break; + + case REFTABLE_REF_DELETION: + break; + default: + abort(); + break; + } + + return start.len - in.len; +} + +static int reftable_ref_record_is_deletion_void(const void *p) +{ + return reftable_ref_record_is_deletion( + (const struct reftable_ref_record *)p); +} + + +static int reftable_ref_record_equal_void(const void *a, + const void *b, int hash_size) +{ + struct reftable_ref_record *ra = (struct reftable_ref_record *) a; + struct reftable_ref_record *rb = (struct reftable_ref_record *) b; + return reftable_ref_record_equal(ra, rb, hash_size); +} + +static void reftable_ref_record_print_void(const void *rec, + int hash_size) +{ + reftable_ref_record_print_sz((struct reftable_ref_record *) rec, hash_size); +} + +static struct reftable_record_vtable reftable_ref_record_vtable = { + .key = &reftable_ref_record_key, + .type = BLOCK_TYPE_REF, + .copy_from = &reftable_ref_record_copy_from, + .val_type = &reftable_ref_record_val_type, + .encode = &reftable_ref_record_encode, + .decode = &reftable_ref_record_decode, + .release = &reftable_ref_record_release_void, + .is_deletion = &reftable_ref_record_is_deletion_void, + .equal = &reftable_ref_record_equal_void, + .print = &reftable_ref_record_print_void, +}; + +static void reftable_obj_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_obj_record *rec = + (const struct reftable_obj_record *)r; + strbuf_reset(dest); + strbuf_add(dest, rec->hash_prefix, rec->hash_prefix_len); +} + +static void reftable_obj_record_release(void *rec) +{ + struct reftable_obj_record *obj = rec; + FREE_AND_NULL(obj->hash_prefix); + FREE_AND_NULL(obj->offsets); + memset(obj, 0, sizeof(struct reftable_obj_record)); +} + +static void reftable_obj_record_print(const void *rec, int hash_size) +{ + const struct reftable_obj_record *obj = rec; + char hex[GIT_MAX_HEXSZ + 1] = { 0 }; + struct strbuf offset_str = STRBUF_INIT; + int i; + + for (i = 0; i < obj->offset_len; i++) + strbuf_addf(&offset_str, "%" PRIu64 " ", obj->offsets[i]); + hex_format(hex, obj->hash_prefix, obj->hash_prefix_len); + printf("prefix %s (len %d), offsets [%s]\n", + hex, obj->hash_prefix_len, offset_str.buf); + strbuf_release(&offset_str); +} + +static void reftable_obj_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_obj_record *obj = rec; + const struct reftable_obj_record *src = + (const struct reftable_obj_record *)src_rec; + + reftable_obj_record_release(obj); + obj->hash_prefix = reftable_malloc(src->hash_prefix_len); + obj->hash_prefix_len = src->hash_prefix_len; + if (src->hash_prefix_len) + memcpy(obj->hash_prefix, src->hash_prefix, obj->hash_prefix_len); + + obj->offsets = reftable_malloc(src->offset_len * sizeof(uint64_t)); + obj->offset_len = src->offset_len; + COPY_ARRAY(obj->offsets, src->offsets, src->offset_len); +} + +static uint8_t reftable_obj_record_val_type(const void *rec) +{ + const struct reftable_obj_record *r = rec; + if (r->offset_len > 0 && r->offset_len < 8) + return r->offset_len; + return 0; +} + +static int reftable_obj_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + const struct reftable_obj_record *r = rec; + struct string_view start = s; + int i = 0; + int n = 0; + uint64_t last = 0; + if (r->offset_len == 0 || r->offset_len >= 8) { + n = put_var_int(&s, r->offset_len); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + } + if (r->offset_len == 0) + return start.len - s.len; + n = put_var_int(&s, r->offsets[0]); + if (n < 0) + return -1; + string_view_consume(&s, n); + + last = r->offsets[0]; + for (i = 1; i < r->offset_len; i++) { + int n = put_var_int(&s, r->offsets[i] - last); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + last = r->offsets[i]; + } + return start.len - s.len; +} + +static int reftable_obj_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_obj_record *r = rec; + uint64_t count = val_type; + int n = 0; + uint64_t last; + int j; + r->hash_prefix = reftable_malloc(key.len); + memcpy(r->hash_prefix, key.buf, key.len); + r->hash_prefix_len = key.len; + + if (val_type == 0) { + n = get_var_int(&count, &in); + if (n < 0) { + return n; + } + + string_view_consume(&in, n); + } + + r->offsets = NULL; + r->offset_len = 0; + if (count == 0) + return start.len - in.len; + + r->offsets = reftable_malloc(count * sizeof(uint64_t)); + r->offset_len = count; + + n = get_var_int(&r->offsets[0], &in); + if (n < 0) + return n; + string_view_consume(&in, n); + + last = r->offsets[0]; + j = 1; + while (j < count) { + uint64_t delta = 0; + int n = get_var_int(&delta, &in); + if (n < 0) { + return n; + } + string_view_consume(&in, n); + + last = r->offsets[j] = (delta + last); + j++; + } + return start.len - in.len; +} + +static int not_a_deletion(const void *p) +{ + return 0; +} + +static int reftable_obj_record_equal_void(const void *a, const void *b, int hash_size) +{ + struct reftable_obj_record *ra = (struct reftable_obj_record *) a; + struct reftable_obj_record *rb = (struct reftable_obj_record *) b; + + if (ra->hash_prefix_len != rb->hash_prefix_len + || ra->offset_len != rb->offset_len) + return 0; + + if (ra->hash_prefix_len && + memcmp(ra->hash_prefix, rb->hash_prefix, ra->hash_prefix_len)) + return 0; + if (ra->offset_len && + memcmp(ra->offsets, rb->offsets, ra->offset_len * sizeof(uint64_t))) + return 0; + + return 1; +} + +static struct reftable_record_vtable reftable_obj_record_vtable = { + .key = &reftable_obj_record_key, + .type = BLOCK_TYPE_OBJ, + .copy_from = &reftable_obj_record_copy_from, + .val_type = &reftable_obj_record_val_type, + .encode = &reftable_obj_record_encode, + .decode = &reftable_obj_record_decode, + .release = &reftable_obj_record_release, + .is_deletion = ¬_a_deletion, + .equal = &reftable_obj_record_equal_void, + .print = &reftable_obj_record_print, +}; + +static void reftable_log_record_print_sz(struct reftable_log_record *log, + int hash_size) +{ + char hex[GIT_MAX_HEXSZ + 1] = { 0 }; + + switch (log->value_type) { + case REFTABLE_LOG_DELETION: + printf("log{%s(%" PRIu64 ") delete\n", log->refname, + log->update_index); + break; + case REFTABLE_LOG_UPDATE: + printf("log{%s(%" PRIu64 ") %s <%s> %" PRIu64 " %04d\n", + log->refname, log->update_index, + log->value.update.name ? log->value.update.name : "", + log->value.update.email ? log->value.update.email : "", + log->value.update.time, + log->value.update.tz_offset); + hex_format(hex, log->value.update.old_hash, hash_size); + printf("%s => ", hex); + hex_format(hex, log->value.update.new_hash, hash_size); + printf("%s\n\n%s\n}\n", hex, + log->value.update.message ? log->value.update.message : ""); + break; + } +} + +void reftable_log_record_print(struct reftable_log_record *log, + uint32_t hash_id) +{ + reftable_log_record_print_sz(log, hash_size(hash_id)); +} + +static void reftable_log_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_log_record *rec = + (const struct reftable_log_record *)r; + int len = strlen(rec->refname); + uint8_t i64[8]; + uint64_t ts = 0; + strbuf_reset(dest); + strbuf_add(dest, (uint8_t *)rec->refname, len + 1); + + ts = (~ts) - rec->update_index; + put_be64(&i64[0], ts); + strbuf_add(dest, i64, sizeof(i64)); +} + +static void reftable_log_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_log_record *dst = rec; + const struct reftable_log_record *src = + (const struct reftable_log_record *)src_rec; + + reftable_log_record_release(dst); + *dst = *src; + if (dst->refname) { + dst->refname = xstrdup(dst->refname); + } + switch (dst->value_type) { + case REFTABLE_LOG_DELETION: + break; + case REFTABLE_LOG_UPDATE: + if (dst->value.update.email) { + dst->value.update.email = + xstrdup(dst->value.update.email); + } + if (dst->value.update.name) { + dst->value.update.name = + xstrdup(dst->value.update.name); + } + if (dst->value.update.message) { + dst->value.update.message = + xstrdup(dst->value.update.message); + } + + if (dst->value.update.new_hash) { + dst->value.update.new_hash = reftable_malloc(hash_size); + memcpy(dst->value.update.new_hash, + src->value.update.new_hash, hash_size); + } + if (dst->value.update.old_hash) { + dst->value.update.old_hash = reftable_malloc(hash_size); + memcpy(dst->value.update.old_hash, + src->value.update.old_hash, hash_size); + } + break; + } +} + +static void reftable_log_record_release_void(void *rec) +{ + struct reftable_log_record *r = rec; + reftable_log_record_release(r); +} + +void reftable_log_record_release(struct reftable_log_record *r) +{ + reftable_free(r->refname); + switch (r->value_type) { + case REFTABLE_LOG_DELETION: + break; + case REFTABLE_LOG_UPDATE: + reftable_free(r->value.update.new_hash); + reftable_free(r->value.update.old_hash); + reftable_free(r->value.update.name); + reftable_free(r->value.update.email); + reftable_free(r->value.update.message); + break; + } + memset(r, 0, sizeof(struct reftable_log_record)); +} + +static uint8_t reftable_log_record_val_type(const void *rec) +{ + const struct reftable_log_record *log = + (const struct reftable_log_record *)rec; + + return reftable_log_record_is_deletion(log) ? 0 : 1; +} + +static uint8_t zero[GIT_SHA256_RAWSZ] = { 0 }; + +static int reftable_log_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + const struct reftable_log_record *r = rec; + struct string_view start = s; + int n = 0; + uint8_t *oldh = NULL; + uint8_t *newh = NULL; + if (reftable_log_record_is_deletion(r)) + return 0; + + oldh = r->value.update.old_hash; + newh = r->value.update.new_hash; + if (!oldh) { + oldh = zero; + } + if (!newh) { + newh = zero; + } + + if (s.len < 2 * hash_size) + return -1; + + memcpy(s.buf, oldh, hash_size); + memcpy(s.buf + hash_size, newh, hash_size); + string_view_consume(&s, 2 * hash_size); + + n = encode_string(r->value.update.name ? r->value.update.name : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + n = encode_string(r->value.update.email ? r->value.update.email : "", + s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + n = put_var_int(&s, r->value.update.time); + if (n < 0) + return -1; + string_view_consume(&s, n); + + if (s.len < 2) + return -1; + + put_be16(s.buf, r->value.update.tz_offset); + string_view_consume(&s, 2); + + n = encode_string( + r->value.update.message ? r->value.update.message : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + return start.len - s.len; +} + +static int reftable_log_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_log_record *r = rec; + uint64_t max = 0; + uint64_t ts = 0; + struct strbuf dest = STRBUF_INIT; + int n; + + if (key.len <= 9 || key.buf[key.len - 9] != 0) + return REFTABLE_FORMAT_ERROR; + + r->refname = reftable_realloc(r->refname, key.len - 8); + memcpy(r->refname, key.buf, key.len - 8); + ts = get_be64(key.buf + key.len - 8); + + r->update_index = (~max) - ts; + + if (val_type != r->value_type) { + switch (r->value_type) { + case REFTABLE_LOG_UPDATE: + FREE_AND_NULL(r->value.update.old_hash); + FREE_AND_NULL(r->value.update.new_hash); + FREE_AND_NULL(r->value.update.message); + FREE_AND_NULL(r->value.update.email); + FREE_AND_NULL(r->value.update.name); + break; + case REFTABLE_LOG_DELETION: + break; + } + } + + r->value_type = val_type; + if (val_type == REFTABLE_LOG_DELETION) + return 0; + + if (in.len < 2 * hash_size) + return REFTABLE_FORMAT_ERROR; + + r->value.update.old_hash = + reftable_realloc(r->value.update.old_hash, hash_size); + r->value.update.new_hash = + reftable_realloc(r->value.update.new_hash, hash_size); + + memcpy(r->value.update.old_hash, in.buf, hash_size); + memcpy(r->value.update.new_hash, in.buf + hash_size, hash_size); + + string_view_consume(&in, 2 * hash_size); + + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->value.update.name = + reftable_realloc(r->value.update.name, dest.len + 1); + memcpy(r->value.update.name, dest.buf, dest.len); + r->value.update.name[dest.len] = 0; + + strbuf_reset(&dest); + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->value.update.email = + reftable_realloc(r->value.update.email, dest.len + 1); + memcpy(r->value.update.email, dest.buf, dest.len); + r->value.update.email[dest.len] = 0; + + ts = 0; + n = get_var_int(&ts, &in); + if (n < 0) + goto done; + string_view_consume(&in, n); + r->value.update.time = ts; + if (in.len < 2) + goto done; + + r->value.update.tz_offset = get_be16(in.buf); + string_view_consume(&in, 2); + + strbuf_reset(&dest); + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->value.update.message = + reftable_realloc(r->value.update.message, dest.len + 1); + memcpy(r->value.update.message, dest.buf, dest.len); + r->value.update.message[dest.len] = 0; + + strbuf_release(&dest); + return start.len - in.len; + +done: + strbuf_release(&dest); + return REFTABLE_FORMAT_ERROR; +} + +static int null_streq(char *a, char *b) +{ + char *empty = ""; + if (!a) + a = empty; + + if (!b) + b = empty; + + return 0 == strcmp(a, b); +} + +static int zero_hash_eq(uint8_t *a, uint8_t *b, int sz) +{ + if (!a) + a = zero; + + if (!b) + b = zero; + + return !memcmp(a, b, sz); +} + +static int reftable_log_record_equal_void(const void *a, + const void *b, int hash_size) +{ + return reftable_log_record_equal((struct reftable_log_record *) a, + (struct reftable_log_record *) b, + hash_size); +} + +int reftable_log_record_equal(const struct reftable_log_record *a, + const struct reftable_log_record *b, int hash_size) +{ + if (!(null_streq(a->refname, b->refname) && + a->update_index == b->update_index && + a->value_type == b->value_type)) + return 0; + + switch (a->value_type) { + case REFTABLE_LOG_DELETION: + return 1; + case REFTABLE_LOG_UPDATE: + return null_streq(a->value.update.name, b->value.update.name) && + a->value.update.time == b->value.update.time && + a->value.update.tz_offset == b->value.update.tz_offset && + null_streq(a->value.update.email, + b->value.update.email) && + null_streq(a->value.update.message, + b->value.update.message) && + zero_hash_eq(a->value.update.old_hash, + b->value.update.old_hash, hash_size) && + zero_hash_eq(a->value.update.new_hash, + b->value.update.new_hash, hash_size); + } + + abort(); +} + +static int reftable_log_record_is_deletion_void(const void *p) +{ + return reftable_log_record_is_deletion( + (const struct reftable_log_record *)p); +} + +static void reftable_log_record_print_void(const void *rec, int hash_size) +{ + reftable_log_record_print_sz((struct reftable_log_record*)rec, hash_size); +} + +static struct reftable_record_vtable reftable_log_record_vtable = { + .key = &reftable_log_record_key, + .type = BLOCK_TYPE_LOG, + .copy_from = &reftable_log_record_copy_from, + .val_type = &reftable_log_record_val_type, + .encode = &reftable_log_record_encode, + .decode = &reftable_log_record_decode, + .release = &reftable_log_record_release_void, + .is_deletion = &reftable_log_record_is_deletion_void, + .equal = &reftable_log_record_equal_void, + .print = &reftable_log_record_print_void, +}; + +static void reftable_index_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_index_record *rec = r; + strbuf_reset(dest); + strbuf_addbuf(dest, &rec->last_key); +} + +static void reftable_index_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_index_record *dst = rec; + const struct reftable_index_record *src = src_rec; + + strbuf_reset(&dst->last_key); + strbuf_addbuf(&dst->last_key, &src->last_key); + dst->offset = src->offset; +} + +static void reftable_index_record_release(void *rec) +{ + struct reftable_index_record *idx = rec; + strbuf_release(&idx->last_key); +} + +static uint8_t reftable_index_record_val_type(const void *rec) +{ + return 0; +} + +static int reftable_index_record_encode(const void *rec, struct string_view out, + int hash_size) +{ + const struct reftable_index_record *r = + (const struct reftable_index_record *)rec; + struct string_view start = out; + + int n = put_var_int(&out, r->offset); + if (n < 0) + return n; + + string_view_consume(&out, n); + + return start.len - out.len; +} + +static int reftable_index_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_index_record *r = rec; + int n = 0; + + strbuf_reset(&r->last_key); + strbuf_addbuf(&r->last_key, &key); + + n = get_var_int(&r->offset, &in); + if (n < 0) + return n; + + string_view_consume(&in, n); + return start.len - in.len; +} + +static int reftable_index_record_equal(const void *a, const void *b, int hash_size) +{ + struct reftable_index_record *ia = (struct reftable_index_record *) a; + struct reftable_index_record *ib = (struct reftable_index_record *) b; + + return ia->offset == ib->offset && !strbuf_cmp(&ia->last_key, &ib->last_key); +} + +static void reftable_index_record_print(const void *rec, int hash_size) +{ + const struct reftable_index_record *idx = rec; + /* TODO: escape null chars? */ + printf("\"%s\" %" PRIu64 "\n", idx->last_key.buf, idx->offset); +} + +static struct reftable_record_vtable reftable_index_record_vtable = { + .key = &reftable_index_record_key, + .type = BLOCK_TYPE_INDEX, + .copy_from = &reftable_index_record_copy_from, + .val_type = &reftable_index_record_val_type, + .encode = &reftable_index_record_encode, + .decode = &reftable_index_record_decode, + .release = &reftable_index_record_release, + .is_deletion = ¬_a_deletion, + .equal = &reftable_index_record_equal, + .print = &reftable_index_record_print, +}; + +void reftable_record_key(struct reftable_record *rec, struct strbuf *dest) +{ + reftable_record_vtable(rec)->key(reftable_record_data(rec), dest); +} + +uint8_t reftable_record_type(struct reftable_record *rec) +{ + return rec->type; +} + +int reftable_record_encode(struct reftable_record *rec, struct string_view dest, + int hash_size) +{ + return reftable_record_vtable(rec)->encode(reftable_record_data(rec), + dest, hash_size); +} + +void reftable_record_copy_from(struct reftable_record *rec, + struct reftable_record *src, int hash_size) +{ + assert(src->type == rec->type); + + reftable_record_vtable(rec)->copy_from(reftable_record_data(rec), + reftable_record_data(src), + hash_size); +} + +uint8_t reftable_record_val_type(struct reftable_record *rec) +{ + return reftable_record_vtable(rec)->val_type(reftable_record_data(rec)); +} + +int reftable_record_decode(struct reftable_record *rec, struct strbuf key, + uint8_t extra, struct string_view src, int hash_size) +{ + return reftable_record_vtable(rec)->decode(reftable_record_data(rec), + key, extra, src, hash_size); +} + +void reftable_record_release(struct reftable_record *rec) +{ + reftable_record_vtable(rec)->release(reftable_record_data(rec)); +} + +int reftable_record_is_deletion(struct reftable_record *rec) +{ + return reftable_record_vtable(rec)->is_deletion( + reftable_record_data(rec)); +} + +int reftable_record_equal(struct reftable_record *a, struct reftable_record *b, int hash_size) +{ + if (a->type != b->type) + return 0; + return reftable_record_vtable(a)->equal( + reftable_record_data(a), reftable_record_data(b), hash_size); +} + +static int hash_equal(uint8_t *a, uint8_t *b, int hash_size) +{ + if (a && b) + return !memcmp(a, b, hash_size); + + return a == b; +} + +int reftable_ref_record_equal(const struct reftable_ref_record *a, + const struct reftable_ref_record *b, int hash_size) +{ + assert(hash_size > 0); + if (!null_streq(a->refname, b->refname)) + return 0; + + if (a->update_index != b->update_index || + a->value_type != b->value_type) + return 0; + + switch (a->value_type) { + case REFTABLE_REF_SYMREF: + return !strcmp(a->value.symref, b->value.symref); + case REFTABLE_REF_VAL2: + return hash_equal(a->value.val2.value, b->value.val2.value, + hash_size) && + hash_equal(a->value.val2.target_value, + b->value.val2.target_value, hash_size); + case REFTABLE_REF_VAL1: + return hash_equal(a->value.val1, b->value.val1, hash_size); + case REFTABLE_REF_DELETION: + return 1; + default: + abort(); + } +} + +int reftable_ref_record_compare_name(const void *a, const void *b) +{ + return strcmp(((struct reftable_ref_record *)a)->refname, + ((struct reftable_ref_record *)b)->refname); +} + +int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref) +{ + return ref->value_type == REFTABLE_REF_DELETION; +} + +int reftable_log_record_compare_key(const void *a, const void *b) +{ + const struct reftable_log_record *la = a; + const struct reftable_log_record *lb = b; + + int cmp = strcmp(la->refname, lb->refname); + if (cmp) + return cmp; + if (la->update_index > lb->update_index) + return -1; + return (la->update_index < lb->update_index) ? 1 : 0; +} + +int reftable_log_record_is_deletion(const struct reftable_log_record *log) +{ + return (log->value_type == REFTABLE_LOG_DELETION); +} + +void string_view_consume(struct string_view *s, int n) +{ + s->buf += n; + s->len -= n; +} + +static void *reftable_record_data(struct reftable_record *rec) +{ + switch (rec->type) { + case BLOCK_TYPE_REF: + return &rec->u.ref; + case BLOCK_TYPE_LOG: + return &rec->u.log; + case BLOCK_TYPE_INDEX: + return &rec->u.idx; + case BLOCK_TYPE_OBJ: + return &rec->u.obj; + } + abort(); +} + +static struct reftable_record_vtable * +reftable_record_vtable(struct reftable_record *rec) +{ + switch (rec->type) { + case BLOCK_TYPE_REF: + return &reftable_ref_record_vtable; + case BLOCK_TYPE_LOG: + return &reftable_log_record_vtable; + case BLOCK_TYPE_INDEX: + return &reftable_index_record_vtable; + case BLOCK_TYPE_OBJ: + return &reftable_obj_record_vtable; + } + abort(); +} + +struct reftable_record reftable_new_record(uint8_t typ) +{ + struct reftable_record clean = { + .type = typ, + }; + + /* the following is involved, but the naive solution (just return + * `clean` as is, except for BLOCK_TYPE_INDEX), returns a garbage + * clean.u.obj.offsets pointer on Windows VS CI. Go figure. + */ + switch (typ) { + case BLOCK_TYPE_OBJ: + { + struct reftable_obj_record obj = { 0 }; + clean.u.obj = obj; + break; + } + case BLOCK_TYPE_INDEX: + { + struct reftable_index_record idx = { + .last_key = STRBUF_INIT, + }; + clean.u.idx = idx; + break; + } + case BLOCK_TYPE_REF: + { + struct reftable_ref_record ref = { 0 }; + clean.u.ref = ref; + break; + } + case BLOCK_TYPE_LOG: + { + struct reftable_log_record log = { 0 }; + clean.u.log = log; + break; + } + } + return clean; +} + +void reftable_record_print(struct reftable_record *rec, int hash_size) +{ + printf("'%c': ", rec->type); + reftable_record_vtable(rec)->print(reftable_record_data(rec), hash_size); +} diff --git a/reftable/record.h b/reftable/record.h new file mode 100644 index 0000000000..fd80cd451d --- /dev/null +++ b/reftable/record.h @@ -0,0 +1,140 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef RECORD_H +#define RECORD_H + +#include "system.h" + +#include <stdint.h> + +#include "reftable-record.h" + +/* + * A substring of existing string data. This structure takes no responsibility + * for the lifetime of the data it points to. + */ +struct string_view { + uint8_t *buf; + size_t len; +}; + +/* Advance `s.buf` by `n`, and decrease length. */ +void string_view_consume(struct string_view *s, int n); + +/* utilities for de/encoding varints */ + +int get_var_int(uint64_t *dest, struct string_view *in); +int put_var_int(struct string_view *dest, uint64_t val); + +/* Methods for records. */ +struct reftable_record_vtable { + /* encode the key of to a uint8_t strbuf. */ + void (*key)(const void *rec, struct strbuf *dest); + + /* The record type of ('r' for ref). */ + uint8_t type; + + void (*copy_from)(void *dest, const void *src, int hash_size); + + /* a value of [0..7], indicating record subvariants (eg. ref vs. symref + * vs ref deletion) */ + uint8_t (*val_type)(const void *rec); + + /* encodes rec into dest, returning how much space was used. */ + int (*encode)(const void *rec, struct string_view dest, int hash_size); + + /* decode data from `src` into the record. */ + int (*decode)(void *rec, struct strbuf key, uint8_t extra, + struct string_view src, int hash_size); + + /* deallocate and null the record. */ + void (*release)(void *rec); + + /* is this a tombstone? */ + int (*is_deletion)(const void *rec); + + /* Are two records equal? This assumes they have the same type. Returns 0 for non-equal. */ + int (*equal)(const void *a, const void *b, int hash_size); + + /* Print on stdout, for debugging. */ + void (*print)(const void *rec, int hash_size); +}; + +/* returns true for recognized block types. Block start with the block type. */ +int reftable_is_block_type(uint8_t typ); + +/* return an initialized record for the given type */ +struct reftable_record reftable_new_record(uint8_t typ); + +/* Encode `key` into `dest`. Sets `is_restart` to indicate a restart. Returns + * number of bytes written. */ +int reftable_encode_key(int *is_restart, struct string_view dest, + struct strbuf prev_key, struct strbuf key, + uint8_t extra); + +/* Decode into `key` and `extra` from `in` */ +int reftable_decode_key(struct strbuf *key, uint8_t *extra, + struct strbuf last_key, struct string_view in); + +/* reftable_index_record are used internally to speed up lookups. */ +struct reftable_index_record { + uint64_t offset; /* Offset of block */ + struct strbuf last_key; /* Last key of the block. */ +}; + +/* reftable_obj_record stores an object ID => ref mapping. */ +struct reftable_obj_record { + uint8_t *hash_prefix; /* leading bytes of the object ID */ + int hash_prefix_len; /* number of leading bytes. Constant + * across a single table. */ + uint64_t *offsets; /* a vector of file offsets. */ + int offset_len; +}; + +/* record is a generic wrapper for different types of records. It is normally + * created on the stack, or embedded within another struct. If the type is + * known, a fresh instance can be initialized explicitly. Otherwise, use + * reftable_new_record() to initialize generically (as the index_record is not + * valid as 0-initialized structure) + */ +struct reftable_record { + uint8_t type; + union { + struct reftable_ref_record ref; + struct reftable_log_record log; + struct reftable_obj_record obj; + struct reftable_index_record idx; + } u; +}; + +/* see struct record_vtable */ +int reftable_record_equal(struct reftable_record *a, struct reftable_record *b, int hash_size); +void reftable_record_print(struct reftable_record *rec, int hash_size); +void reftable_record_key(struct reftable_record *rec, struct strbuf *dest); +uint8_t reftable_record_type(struct reftable_record *rec); +void reftable_record_copy_from(struct reftable_record *rec, + struct reftable_record *src, int hash_size); +uint8_t reftable_record_val_type(struct reftable_record *rec); +int reftable_record_encode(struct reftable_record *rec, struct string_view dest, + int hash_size); +int reftable_record_decode(struct reftable_record *rec, struct strbuf key, + uint8_t extra, struct string_view src, + int hash_size); +int reftable_record_is_deletion(struct reftable_record *rec); + +/* frees and zeroes out the embedded record */ +void reftable_record_release(struct reftable_record *rec); + +/* for qsort. */ +int reftable_ref_record_compare_name(const void *a, const void *b); + +/* for qsort. */ +int reftable_log_record_compare_key(const void *a, const void *b); + +#endif diff --git a/reftable/record_test.c b/reftable/record_test.c new file mode 100644 index 0000000000..70ae78feca --- /dev/null +++ b/reftable/record_test.c @@ -0,0 +1,419 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ + +#include "record.h" + +#include "system.h" +#include "basics.h" +#include "constants.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static void test_copy(struct reftable_record *rec) +{ + struct reftable_record copy = { 0 }; + uint8_t typ; + + typ = reftable_record_type(rec); + copy = reftable_new_record(typ); + reftable_record_copy_from(©, rec, GIT_SHA1_RAWSZ); + /* do it twice to catch memory leaks */ + reftable_record_copy_from(©, rec, GIT_SHA1_RAWSZ); + EXPECT(reftable_record_equal(rec, ©, GIT_SHA1_RAWSZ)); + + puts("testing print coverage:\n"); + reftable_record_print(©, GIT_SHA1_RAWSZ); + + reftable_record_release(©); +} + +static void test_varint_roundtrip(void) +{ + uint64_t inputs[] = { 0, + 1, + 27, + 127, + 128, + 257, + 4096, + ((uint64_t)1 << 63), + ((uint64_t)1 << 63) + ((uint64_t)1 << 63) - 1 }; + int i = 0; + for (i = 0; i < ARRAY_SIZE(inputs); i++) { + uint8_t dest[10]; + + struct string_view out = { + .buf = dest, + .len = sizeof(dest), + }; + uint64_t in = inputs[i]; + int n = put_var_int(&out, in); + uint64_t got = 0; + + EXPECT(n > 0); + out.len = n; + n = get_var_int(&got, &out); + EXPECT(n > 0); + + EXPECT(got == in); + } +} + +static void test_common_prefix(void) +{ + struct { + const char *a, *b; + int want; + } cases[] = { + { "abc", "ab", 2 }, + { "", "abc", 0 }, + { "abc", "abd", 2 }, + { "abc", "pqr", 0 }, + }; + + int i = 0; + for (i = 0; i < ARRAY_SIZE(cases); i++) { + struct strbuf a = STRBUF_INIT; + struct strbuf b = STRBUF_INIT; + strbuf_addstr(&a, cases[i].a); + strbuf_addstr(&b, cases[i].b); + EXPECT(common_prefix_size(&a, &b) == cases[i].want); + + strbuf_release(&a); + strbuf_release(&b); + } +} + +static void set_hash(uint8_t *h, int j) +{ + int i = 0; + for (i = 0; i < hash_size(GIT_SHA1_FORMAT_ID); i++) { + h[i] = (j >> i) & 0xff; + } +} + +static void test_reftable_ref_record_roundtrip(void) +{ + int i = 0; + + for (i = REFTABLE_REF_DELETION; i < REFTABLE_NR_REF_VALUETYPES; i++) { + struct reftable_record in = { + .type = BLOCK_TYPE_REF, + }; + struct reftable_record out = { .type = BLOCK_TYPE_REF }; + struct strbuf key = STRBUF_INIT; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + int n, m; + + in.u.ref.value_type = i; + switch (i) { + case REFTABLE_REF_DELETION: + break; + case REFTABLE_REF_VAL1: + in.u.ref.value.val1 = reftable_malloc(GIT_SHA1_RAWSZ); + set_hash(in.u.ref.value.val1, 1); + break; + case REFTABLE_REF_VAL2: + in.u.ref.value.val2.value = + reftable_malloc(GIT_SHA1_RAWSZ); + set_hash(in.u.ref.value.val2.value, 1); + in.u.ref.value.val2.target_value = + reftable_malloc(GIT_SHA1_RAWSZ); + set_hash(in.u.ref.value.val2.target_value, 2); + break; + case REFTABLE_REF_SYMREF: + in.u.ref.value.symref = xstrdup("target"); + break; + } + in.u.ref.refname = xstrdup("refs/heads/master"); + + test_copy(&in); + + EXPECT(reftable_record_val_type(&in) == i); + + reftable_record_key(&in, &key); + n = reftable_record_encode(&in, dest, GIT_SHA1_RAWSZ); + EXPECT(n > 0); + + /* decode into a non-zero reftable_record to test for leaks. */ + m = reftable_record_decode(&out, key, i, dest, GIT_SHA1_RAWSZ); + EXPECT(n == m); + + EXPECT(reftable_ref_record_equal(&in.u.ref, &out.u.ref, + GIT_SHA1_RAWSZ)); + reftable_record_release(&in); + + strbuf_release(&key); + reftable_record_release(&out); + } +} + +static void test_reftable_log_record_equal(void) +{ + struct reftable_log_record in[2] = { + { + .refname = xstrdup("refs/heads/master"), + .update_index = 42, + }, + { + .refname = xstrdup("refs/heads/master"), + .update_index = 22, + } + }; + + EXPECT(!reftable_log_record_equal(&in[0], &in[1], GIT_SHA1_RAWSZ)); + in[1].update_index = in[0].update_index; + EXPECT(reftable_log_record_equal(&in[0], &in[1], GIT_SHA1_RAWSZ)); + reftable_log_record_release(&in[0]); + reftable_log_record_release(&in[1]); +} + +static void test_reftable_log_record_roundtrip(void) +{ + int i; + + struct reftable_log_record in[] = { + { + .refname = xstrdup("refs/heads/master"), + .update_index = 42, + .value_type = REFTABLE_LOG_UPDATE, + .value = { + .update = { + .old_hash = reftable_malloc(GIT_SHA1_RAWSZ), + .new_hash = reftable_malloc(GIT_SHA1_RAWSZ), + .name = xstrdup("han-wen"), + .email = xstrdup("hanwen@google.com"), + .message = xstrdup("test"), + .time = 1577123507, + .tz_offset = 100, + }, + } + }, + { + .refname = xstrdup("refs/heads/master"), + .update_index = 22, + .value_type = REFTABLE_LOG_DELETION, + }, + { + .refname = xstrdup("branch"), + .update_index = 33, + .value_type = REFTABLE_LOG_UPDATE, + .value = { + .update = { + .old_hash = reftable_malloc(GIT_SHA1_RAWSZ), + .new_hash = reftable_malloc(GIT_SHA1_RAWSZ), + /* rest of fields left empty. */ + }, + }, + } + }; + set_test_hash(in[0].value.update.new_hash, 1); + set_test_hash(in[0].value.update.old_hash, 2); + set_test_hash(in[2].value.update.new_hash, 3); + set_test_hash(in[2].value.update.old_hash, 4); + for (i = 0; i < ARRAY_SIZE(in); i++) { + struct reftable_record rec = { .type = BLOCK_TYPE_LOG }; + struct strbuf key = STRBUF_INIT; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + /* populate out, to check for leaks. */ + struct reftable_record out = { + .type = BLOCK_TYPE_LOG, + .u.log = { + .refname = xstrdup("old name"), + .value_type = REFTABLE_LOG_UPDATE, + .value = { + .update = { + .new_hash = reftable_calloc(GIT_SHA1_RAWSZ), + .old_hash = reftable_calloc(GIT_SHA1_RAWSZ), + .name = xstrdup("old name"), + .email = xstrdup("old@email"), + .message = xstrdup("old message"), + }, + }, + }, + }; + int n, m, valtype; + + rec.u.log = in[i]; + + test_copy(&rec); + + reftable_record_key(&rec, &key); + + n = reftable_record_encode(&rec, dest, GIT_SHA1_RAWSZ); + EXPECT(n >= 0); + valtype = reftable_record_val_type(&rec); + m = reftable_record_decode(&out, key, valtype, dest, + GIT_SHA1_RAWSZ); + EXPECT(n == m); + + EXPECT(reftable_log_record_equal(&in[i], &out.u.log, + GIT_SHA1_RAWSZ)); + reftable_log_record_release(&in[i]); + strbuf_release(&key); + reftable_record_release(&out); + } +} + +static void test_u24_roundtrip(void) +{ + uint32_t in = 0x112233; + uint8_t dest[3]; + uint32_t out; + put_be24(dest, in); + out = get_be24(dest); + EXPECT(in == out); +} + +static void test_key_roundtrip(void) +{ + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + struct strbuf last_key = STRBUF_INIT; + struct strbuf key = STRBUF_INIT; + struct strbuf roundtrip = STRBUF_INIT; + int restart; + uint8_t extra; + int n, m; + uint8_t rt_extra; + + strbuf_addstr(&last_key, "refs/heads/master"); + strbuf_addstr(&key, "refs/tags/bla"); + extra = 6; + n = reftable_encode_key(&restart, dest, last_key, key, extra); + EXPECT(!restart); + EXPECT(n > 0); + + m = reftable_decode_key(&roundtrip, &rt_extra, last_key, dest); + EXPECT(n == m); + EXPECT(0 == strbuf_cmp(&key, &roundtrip)); + EXPECT(rt_extra == extra); + + strbuf_release(&last_key); + strbuf_release(&key); + strbuf_release(&roundtrip); +} + +static void test_reftable_obj_record_roundtrip(void) +{ + uint8_t testHash1[GIT_SHA1_RAWSZ] = { 1, 2, 3, 4, 0 }; + uint64_t till9[] = { 1, 2, 3, 4, 500, 600, 700, 800, 9000 }; + struct reftable_obj_record recs[3] = { { + .hash_prefix = testHash1, + .hash_prefix_len = 5, + .offsets = till9, + .offset_len = 3, + }, + { + .hash_prefix = testHash1, + .hash_prefix_len = 5, + .offsets = till9, + .offset_len = 9, + }, + { + .hash_prefix = testHash1, + .hash_prefix_len = 5, + } }; + int i = 0; + for (i = 0; i < ARRAY_SIZE(recs); i++) { + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + struct reftable_record in = { + .type = BLOCK_TYPE_OBJ, + .u = { + .obj = recs[i], + }, + }; + struct strbuf key = STRBUF_INIT; + struct reftable_record out = { .type = BLOCK_TYPE_OBJ }; + int n, m; + uint8_t extra; + + test_copy(&in); + reftable_record_key(&in, &key); + n = reftable_record_encode(&in, dest, GIT_SHA1_RAWSZ); + EXPECT(n > 0); + extra = reftable_record_val_type(&in); + m = reftable_record_decode(&out, key, extra, dest, + GIT_SHA1_RAWSZ); + EXPECT(n == m); + + EXPECT(reftable_record_equal(&in, &out, GIT_SHA1_RAWSZ)); + strbuf_release(&key); + reftable_record_release(&out); + } +} + +static void test_reftable_index_record_roundtrip(void) +{ + struct reftable_record in = { + .type = BLOCK_TYPE_INDEX, + .u.idx = { + .offset = 42, + .last_key = STRBUF_INIT, + }, + }; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + struct strbuf key = STRBUF_INIT; + struct reftable_record out = { + .type = BLOCK_TYPE_INDEX, + .u.idx = { .last_key = STRBUF_INIT }, + }; + int n, m; + uint8_t extra; + + strbuf_addstr(&in.u.idx.last_key, "refs/heads/master"); + reftable_record_key(&in, &key); + test_copy(&in); + + EXPECT(0 == strbuf_cmp(&key, &in.u.idx.last_key)); + n = reftable_record_encode(&in, dest, GIT_SHA1_RAWSZ); + EXPECT(n > 0); + + extra = reftable_record_val_type(&in); + m = reftable_record_decode(&out, key, extra, dest, GIT_SHA1_RAWSZ); + EXPECT(m == n); + + EXPECT(reftable_record_equal(&in, &out, GIT_SHA1_RAWSZ)); + + reftable_record_release(&out); + strbuf_release(&key); + strbuf_release(&in.u.idx.last_key); +} + +int record_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_reftable_log_record_equal); + RUN_TEST(test_reftable_log_record_roundtrip); + RUN_TEST(test_reftable_ref_record_roundtrip); + RUN_TEST(test_varint_roundtrip); + RUN_TEST(test_key_roundtrip); + RUN_TEST(test_common_prefix); + RUN_TEST(test_reftable_obj_record_roundtrip); + RUN_TEST(test_reftable_index_record_roundtrip); + RUN_TEST(test_u24_roundtrip); + return 0; +} diff --git a/reftable/refname.c b/reftable/refname.c new file mode 100644 index 0000000000..9573496932 --- /dev/null +++ b/reftable/refname.c @@ -0,0 +1,209 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" +#include "reftable-error.h" +#include "basics.h" +#include "refname.h" +#include "reftable-iterator.h" + +struct find_arg { + char **names; + const char *want; +}; + +static int find_name(size_t k, void *arg) +{ + struct find_arg *f_arg = arg; + return strcmp(f_arg->names[k], f_arg->want) >= 0; +} + +static int modification_has_ref(struct modification *mod, const char *name) +{ + struct reftable_ref_record ref = { NULL }; + int err = 0; + + if (mod->add_len > 0) { + struct find_arg arg = { + .names = mod->add, + .want = name, + }; + int idx = binsearch(mod->add_len, find_name, &arg); + if (idx < mod->add_len && !strcmp(mod->add[idx], name)) { + return 0; + } + } + + if (mod->del_len > 0) { + struct find_arg arg = { + .names = mod->del, + .want = name, + }; + int idx = binsearch(mod->del_len, find_name, &arg); + if (idx < mod->del_len && !strcmp(mod->del[idx], name)) { + return 1; + } + } + + err = reftable_table_read_ref(&mod->tab, name, &ref); + reftable_ref_record_release(&ref); + return err; +} + +static void modification_release(struct modification *mod) +{ + /* don't delete the strings themselves; they're owned by ref records. + */ + FREE_AND_NULL(mod->add); + FREE_AND_NULL(mod->del); + mod->add_len = 0; + mod->del_len = 0; +} + +static int modification_has_ref_with_prefix(struct modification *mod, + const char *prefix) +{ + struct reftable_iterator it = { NULL }; + struct reftable_ref_record ref = { NULL }; + int err = 0; + + if (mod->add_len > 0) { + struct find_arg arg = { + .names = mod->add, + .want = prefix, + }; + int idx = binsearch(mod->add_len, find_name, &arg); + if (idx < mod->add_len && + !strncmp(prefix, mod->add[idx], strlen(prefix))) + goto done; + } + err = reftable_table_seek_ref(&mod->tab, &it, prefix); + if (err) + goto done; + + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err) + goto done; + + if (mod->del_len > 0) { + struct find_arg arg = { + .names = mod->del, + .want = ref.refname, + }; + int idx = binsearch(mod->del_len, find_name, &arg); + if (idx < mod->del_len && + !strcmp(ref.refname, mod->del[idx])) { + continue; + } + } + + if (strncmp(ref.refname, prefix, strlen(prefix))) { + err = 1; + goto done; + } + err = 0; + goto done; + } + +done: + reftable_ref_record_release(&ref); + reftable_iterator_destroy(&it); + return err; +} + +static int validate_refname(const char *name) +{ + while (1) { + char *next = strchr(name, '/'); + if (!*name) { + return REFTABLE_REFNAME_ERROR; + } + if (!next) { + return 0; + } + if (next - name == 0 || (next - name == 1 && *name == '.') || + (next - name == 2 && name[0] == '.' && name[1] == '.')) + return REFTABLE_REFNAME_ERROR; + name = next + 1; + } + return 0; +} + +int validate_ref_record_addition(struct reftable_table tab, + struct reftable_ref_record *recs, size_t sz) +{ + struct modification mod = { + .tab = tab, + .add = reftable_calloc(sizeof(char *) * sz), + .del = reftable_calloc(sizeof(char *) * sz), + }; + int i = 0; + int err = 0; + for (; i < sz; i++) { + if (reftable_ref_record_is_deletion(&recs[i])) { + mod.del[mod.del_len++] = recs[i].refname; + } else { + mod.add[mod.add_len++] = recs[i].refname; + } + } + + err = modification_validate(&mod); + modification_release(&mod); + return err; +} + +static void strbuf_trim_component(struct strbuf *sl) +{ + while (sl->len > 0) { + int is_slash = (sl->buf[sl->len - 1] == '/'); + strbuf_setlen(sl, sl->len - 1); + if (is_slash) + break; + } +} + +int modification_validate(struct modification *mod) +{ + struct strbuf slashed = STRBUF_INIT; + int err = 0; + int i = 0; + for (; i < mod->add_len; i++) { + err = validate_refname(mod->add[i]); + if (err) + goto done; + strbuf_reset(&slashed); + strbuf_addstr(&slashed, mod->add[i]); + strbuf_addstr(&slashed, "/"); + + err = modification_has_ref_with_prefix(mod, slashed.buf); + if (err == 0) { + err = REFTABLE_NAME_CONFLICT; + goto done; + } + if (err < 0) + goto done; + + strbuf_reset(&slashed); + strbuf_addstr(&slashed, mod->add[i]); + while (slashed.len) { + strbuf_trim_component(&slashed); + err = modification_has_ref(mod, slashed.buf); + if (err == 0) { + err = REFTABLE_NAME_CONFLICT; + goto done; + } + if (err < 0) + goto done; + } + } + err = 0; +done: + strbuf_release(&slashed); + return err; +} diff --git a/reftable/refname.h b/reftable/refname.h new file mode 100644 index 0000000000..a24b40fcb4 --- /dev/null +++ b/reftable/refname.h @@ -0,0 +1,29 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ +#ifndef REFNAME_H +#define REFNAME_H + +#include "reftable-record.h" +#include "reftable-generic.h" + +struct modification { + struct reftable_table tab; + + char **add; + size_t add_len; + + char **del; + size_t del_len; +}; + +int validate_ref_record_addition(struct reftable_table tab, + struct reftable_ref_record *recs, size_t sz); + +int modification_validate(struct modification *mod); + +#endif diff --git a/reftable/refname_test.c b/reftable/refname_test.c new file mode 100644 index 0000000000..8645cd93bb --- /dev/null +++ b/reftable/refname_test.c @@ -0,0 +1,102 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "basics.h" +#include "block.h" +#include "blocksource.h" +#include "constants.h" +#include "reader.h" +#include "record.h" +#include "refname.h" +#include "reftable-error.h" +#include "reftable-writer.h" +#include "system.h" + +#include "test_framework.h" +#include "reftable-tests.h" + +struct testcase { + char *add; + char *del; + int error_code; +}; + +static void test_conflict(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + struct reftable_ref_record rec = { + .refname = "a/b", + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "destination", /* make sure it's not a symref. + */ + .update_index = 1, + }; + int err; + int i; + struct reftable_block_source source = { NULL }; + struct reftable_reader *rd = NULL; + struct reftable_table tab = { NULL }; + struct testcase cases[] = { + { "a/b/c", NULL, REFTABLE_NAME_CONFLICT }, + { "b", NULL, 0 }, + { "a", NULL, REFTABLE_NAME_CONFLICT }, + { "a", "a/b", 0 }, + + { "p/", NULL, REFTABLE_REFNAME_ERROR }, + { "p//q", NULL, REFTABLE_REFNAME_ERROR }, + { "p/./q", NULL, REFTABLE_REFNAME_ERROR }, + { "p/../q", NULL, REFTABLE_REFNAME_ERROR }, + + { "a/b/c", "a/b", 0 }, + { NULL, "a//b", 0 }, + }; + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_add_ref(w, &rec); + EXPECT_ERR(err); + + err = reftable_writer_close(w); + EXPECT_ERR(err); + reftable_writer_free(w); + + block_source_from_strbuf(&source, &buf); + err = reftable_new_reader(&rd, &source, "filename"); + EXPECT_ERR(err); + + reftable_table_from_reader(&tab, rd); + + for (i = 0; i < ARRAY_SIZE(cases); i++) { + struct modification mod = { + .tab = tab, + }; + + if (cases[i].add) { + mod.add = &cases[i].add; + mod.add_len = 1; + } + if (cases[i].del) { + mod.del = &cases[i].del; + mod.del_len = 1; + } + + err = modification_validate(&mod); + EXPECT(err == cases[i].error_code); + } + + reftable_reader_free(rd); + strbuf_release(&buf); +} + +int refname_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_conflict); + return 0; +} diff --git a/reftable/reftable-blocksource.h b/reftable/reftable-blocksource.h new file mode 100644 index 0000000000..5aa3990a57 --- /dev/null +++ b/reftable/reftable-blocksource.h @@ -0,0 +1,49 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_BLOCKSOURCE_H +#define REFTABLE_BLOCKSOURCE_H + +#include <stdint.h> + +/* block_source is a generic wrapper for a seekable readable file. + */ +struct reftable_block_source { + struct reftable_block_source_vtable *ops; + void *arg; +}; + +/* a contiguous segment of bytes. It keeps track of its generating block_source + * so it can return itself into the pool. */ +struct reftable_block { + uint8_t *data; + int len; + struct reftable_block_source source; +}; + +/* block_source_vtable are the operations that make up block_source */ +struct reftable_block_source_vtable { + /* returns the size of a block source */ + uint64_t (*size)(void *source); + + /* reads a segment from the block source. It is an error to read + beyond the end of the block */ + int (*read_block)(void *source, struct reftable_block *dest, + uint64_t off, uint32_t size); + /* mark the block as read; may return the data back to malloc */ + void (*return_block)(void *source, struct reftable_block *blockp); + + /* release all resources associated with the block source */ + void (*close)(void *source); +}; + +/* opens a file on the file system as a block_source */ +int reftable_block_source_from_file(struct reftable_block_source *block_src, + const char *name); + +#endif diff --git a/reftable/reftable-error.h b/reftable/reftable-error.h new file mode 100644 index 0000000000..4c457aaaf8 --- /dev/null +++ b/reftable/reftable-error.h @@ -0,0 +1,66 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_ERROR_H +#define REFTABLE_ERROR_H + +/* + * Errors in reftable calls are signaled with negative integer return values. 0 + * means success. + */ +enum reftable_error { + /* Unexpected file system behavior */ + REFTABLE_IO_ERROR = -2, + + /* Format inconsistency on reading data */ + REFTABLE_FORMAT_ERROR = -3, + + /* File does not exist. Returned from block_source_from_file(), because + * it needs special handling in stack. + */ + REFTABLE_NOT_EXIST_ERROR = -4, + + /* Trying to write out-of-date data. */ + REFTABLE_LOCK_ERROR = -5, + + /* Misuse of the API: + * - on writing a record with NULL refname. + * - on writing a reftable_ref_record outside the table limits + * - on writing a ref or log record before the stack's + * next_update_inde*x + * - on writing a log record with multiline message with + * exact_log_message unset + * - on reading a reftable_ref_record from log iterator, or vice versa. + * + * When a call misuses the API, the internal state of the library is + * kept unchanged. + */ + REFTABLE_API_ERROR = -6, + + /* Decompression error */ + REFTABLE_ZLIB_ERROR = -7, + + /* Wrote a table without blocks. */ + REFTABLE_EMPTY_TABLE_ERROR = -8, + + /* Dir/file conflict. */ + REFTABLE_NAME_CONFLICT = -9, + + /* Invalid ref name. */ + REFTABLE_REFNAME_ERROR = -10, + + /* Entry does not fit. This can happen when writing outsize reflog + messages. */ + REFTABLE_ENTRY_TOO_BIG_ERROR = -11, +}; + +/* convert the numeric error code to a string. The string should not be + * deallocated. */ +const char *reftable_error_str(int err); + +#endif diff --git a/reftable/reftable-generic.h b/reftable/reftable-generic.h new file mode 100644 index 0000000000..d239751a77 --- /dev/null +++ b/reftable/reftable-generic.h @@ -0,0 +1,47 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_GENERIC_H +#define REFTABLE_GENERIC_H + +#include "reftable-iterator.h" + +struct reftable_table_vtable; + +/* + * Provides a unified API for reading tables, either merged tables, or single + * readers. */ +struct reftable_table { + struct reftable_table_vtable *ops; + void *table_arg; +}; + +int reftable_table_seek_log(struct reftable_table *tab, + struct reftable_iterator *it, const char *name); + +int reftable_table_seek_ref(struct reftable_table *tab, + struct reftable_iterator *it, const char *name); + +/* returns the hash ID from a generic reftable_table */ +uint32_t reftable_table_hash_id(struct reftable_table *tab); + +/* returns the max update_index covered by this table. */ +uint64_t reftable_table_max_update_index(struct reftable_table *tab); + +/* returns the min update_index covered by this table. */ +uint64_t reftable_table_min_update_index(struct reftable_table *tab); + +/* convenience function to read a single ref. Returns < 0 for error, 0 + for success, and 1 if ref not found. */ +int reftable_table_read_ref(struct reftable_table *tab, const char *name, + struct reftable_ref_record *ref); + +/* dump table contents onto stdout for debugging */ +int reftable_table_print(struct reftable_table *tab); + +#endif diff --git a/reftable/reftable-iterator.h b/reftable/reftable-iterator.h new file mode 100644 index 0000000000..d3eee7af35 --- /dev/null +++ b/reftable/reftable-iterator.h @@ -0,0 +1,39 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_ITERATOR_H +#define REFTABLE_ITERATOR_H + +#include "reftable-record.h" + +struct reftable_iterator_vtable; + +/* iterator is the generic interface for walking over data stored in a + * reftable. + */ +struct reftable_iterator { + struct reftable_iterator_vtable *ops; + void *iter_arg; +}; + +/* reads the next reftable_ref_record. Returns < 0 for error, 0 for OK and > 0: + * end of iteration. + */ +int reftable_iterator_next_ref(struct reftable_iterator *it, + struct reftable_ref_record *ref); + +/* reads the next reftable_log_record. Returns < 0 for error, 0 for OK and > 0: + * end of iteration. + */ +int reftable_iterator_next_log(struct reftable_iterator *it, + struct reftable_log_record *log); + +/* releases resources associated with an iterator. */ +void reftable_iterator_destroy(struct reftable_iterator *it); + +#endif diff --git a/reftable/reftable-malloc.h b/reftable/reftable-malloc.h new file mode 100644 index 0000000000..5f2185f1f3 --- /dev/null +++ b/reftable/reftable-malloc.h @@ -0,0 +1,18 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_H +#define REFTABLE_H + +#include <stddef.h> + +/* Overrides the functions to use for memory management. */ +void reftable_set_alloc(void *(*malloc)(size_t), + void *(*realloc)(void *, size_t), void (*free)(void *)); + +#endif diff --git a/reftable/reftable-merged.h b/reftable/reftable-merged.h new file mode 100644 index 0000000000..1a6d16915a --- /dev/null +++ b/reftable/reftable-merged.h @@ -0,0 +1,72 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_MERGED_H +#define REFTABLE_MERGED_H + +#include "reftable-iterator.h" + +/* + * Merged tables + * + * A ref database kept in a sequence of table files. The merged_table presents a + * unified view to reading (seeking, iterating) a sequence of immutable tables. + * + * The merged tables are on purpose kept disconnected from their actual storage + * (eg. files on disk), because it is useful to merge tables aren't files. For + * example, the per-workspace and global ref namespace can be implemented as a + * merged table of two stacks of file-backed reftables. + */ + +/* A merged table is implements seeking/iterating over a stack of tables. */ +struct reftable_merged_table; + +/* A generic reftable; see below. */ +struct reftable_table; + +/* reftable_new_merged_table creates a new merged table. It takes ownership of + the stack array. +*/ +int reftable_new_merged_table(struct reftable_merged_table **dest, + struct reftable_table *stack, int n, + uint32_t hash_id); + +/* returns an iterator positioned just before 'name' */ +int reftable_merged_table_seek_ref(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name); + +/* returns an iterator for log entry, at given update_index */ +int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name, uint64_t update_index); + +/* like reftable_merged_table_seek_log_at but look for the newest entry. */ +int reftable_merged_table_seek_log(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name); + +/* returns the max update_index covered by this merged table. */ +uint64_t +reftable_merged_table_max_update_index(struct reftable_merged_table *mt); + +/* returns the min update_index covered by this merged table. */ +uint64_t +reftable_merged_table_min_update_index(struct reftable_merged_table *mt); + +/* releases memory for the merged_table */ +void reftable_merged_table_free(struct reftable_merged_table *m); + +/* return the hash ID of the merged table. */ +uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *m); + +/* create a generic table from reftable_merged_table */ +void reftable_table_from_merged_table(struct reftable_table *tab, + struct reftable_merged_table *table); + +#endif diff --git a/reftable/reftable-reader.h b/reftable/reftable-reader.h new file mode 100644 index 0000000000..4a4bc2fdf8 --- /dev/null +++ b/reftable/reftable-reader.h @@ -0,0 +1,101 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_READER_H +#define REFTABLE_READER_H + +#include "reftable-iterator.h" +#include "reftable-blocksource.h" + +/* + * Reading single tables + * + * The follow routines are for reading single files. For an + * application-level interface, skip ahead to struct + * reftable_merged_table and struct reftable_stack. + */ + +/* The reader struct is a handle to an open reftable file. */ +struct reftable_reader; + +/* Generic table. */ +struct reftable_table; + +/* reftable_new_reader opens a reftable for reading. If successful, + * returns 0 code and sets pp. The name is used for creating a + * stack. Typically, it is the basename of the file. The block source + * `src` is owned by the reader, and is closed on calling + * reftable_reader_destroy(). On error, the block source `src` is + * closed as well. + */ +int reftable_new_reader(struct reftable_reader **pp, + struct reftable_block_source *src, const char *name); + +/* reftable_reader_seek_ref returns an iterator where 'name' would be inserted + in the table. To seek to the start of the table, use name = "". + + example: + + struct reftable_reader *r = NULL; + int err = reftable_new_reader(&r, &src, "filename"); + if (err < 0) { ... } + struct reftable_iterator it = {0}; + err = reftable_reader_seek_ref(r, &it, "refs/heads/master"); + if (err < 0) { ... } + struct reftable_ref_record ref = {0}; + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) { + ..error handling.. + } + ..found.. + } + reftable_iterator_destroy(&it); + reftable_ref_record_release(&ref); +*/ +int reftable_reader_seek_ref(struct reftable_reader *r, + struct reftable_iterator *it, const char *name); + +/* returns the hash ID used in this table. */ +uint32_t reftable_reader_hash_id(struct reftable_reader *r); + +/* seek to logs for the given name, older than update_index. To seek to the + start of the table, use name = "". +*/ +int reftable_reader_seek_log_at(struct reftable_reader *r, + struct reftable_iterator *it, const char *name, + uint64_t update_index); + +/* seek to newest log entry for given name. */ +int reftable_reader_seek_log(struct reftable_reader *r, + struct reftable_iterator *it, const char *name); + +/* closes and deallocates a reader. */ +void reftable_reader_free(struct reftable_reader *); + +/* return an iterator for the refs pointing to `oid`. */ +int reftable_reader_refs_for(struct reftable_reader *r, + struct reftable_iterator *it, uint8_t *oid); + +/* return the max_update_index for a table */ +uint64_t reftable_reader_max_update_index(struct reftable_reader *r); + +/* return the min_update_index for a table */ +uint64_t reftable_reader_min_update_index(struct reftable_reader *r); + +/* creates a generic table from a file reader. */ +void reftable_table_from_reader(struct reftable_table *tab, + struct reftable_reader *reader); + +/* print table onto stdout for debugging. */ +int reftable_reader_print_file(const char *tablename); + +#endif diff --git a/reftable/reftable-record.h b/reftable/reftable-record.h new file mode 100644 index 0000000000..67104f8fbf --- /dev/null +++ b/reftable/reftable-record.h @@ -0,0 +1,114 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_RECORD_H +#define REFTABLE_RECORD_H + +#include <stdint.h> + +/* + * Basic data types + * + * Reftables store the state of each ref in struct reftable_ref_record, and they + * store a sequence of reflog updates in struct reftable_log_record. + */ + +/* reftable_ref_record holds a ref database entry target_value */ +struct reftable_ref_record { + char *refname; /* Name of the ref, malloced. */ + uint64_t update_index; /* Logical timestamp at which this value is + * written */ + + enum { + /* tombstone to hide deletions from earlier tables */ + REFTABLE_REF_DELETION = 0x0, + + /* a simple ref */ + REFTABLE_REF_VAL1 = 0x1, + /* a tag, plus its peeled hash */ + REFTABLE_REF_VAL2 = 0x2, + + /* a symbolic reference */ + REFTABLE_REF_SYMREF = 0x3, +#define REFTABLE_NR_REF_VALUETYPES 4 + } value_type; + union { + uint8_t *val1; /* malloced hash. */ + struct { + uint8_t *value; /* first value, malloced hash */ + uint8_t *target_value; /* second value, malloced hash */ + } val2; + char *symref; /* referent, malloced 0-terminated string */ + } value; +}; + +/* Returns the first hash, or NULL if `rec` is not of type + * REFTABLE_REF_VAL1 or REFTABLE_REF_VAL2. */ +uint8_t *reftable_ref_record_val1(const struct reftable_ref_record *rec); + +/* Returns the second hash, or NULL if `rec` is not of type + * REFTABLE_REF_VAL2. */ +uint8_t *reftable_ref_record_val2(const struct reftable_ref_record *rec); + +/* returns whether 'ref' represents a deletion */ +int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref); + +/* prints a reftable_ref_record onto stdout. Useful for debugging. */ +void reftable_ref_record_print(const struct reftable_ref_record *ref, + uint32_t hash_id); + +/* frees and nulls all pointer values inside `ref`. */ +void reftable_ref_record_release(struct reftable_ref_record *ref); + +/* returns whether two reftable_ref_records are the same. Useful for testing. */ +int reftable_ref_record_equal(const struct reftable_ref_record *a, + const struct reftable_ref_record *b, int hash_size); + +/* reftable_log_record holds a reflog entry */ +struct reftable_log_record { + char *refname; + uint64_t update_index; /* logical timestamp of a transactional update. + */ + + enum { + /* tombstone to hide deletions from earlier tables */ + REFTABLE_LOG_DELETION = 0x0, + + /* a simple update */ + REFTABLE_LOG_UPDATE = 0x1, +#define REFTABLE_NR_LOG_VALUETYPES 2 + } value_type; + + union { + struct { + uint8_t *new_hash; + uint8_t *old_hash; + char *name; + char *email; + uint64_t time; + int16_t tz_offset; + char *message; + } update; + } value; +}; + +/* returns whether 'ref' represents the deletion of a log record. */ +int reftable_log_record_is_deletion(const struct reftable_log_record *log); + +/* frees and nulls all pointer values. */ +void reftable_log_record_release(struct reftable_log_record *log); + +/* returns whether two records are equal. Useful for testing. */ +int reftable_log_record_equal(const struct reftable_log_record *a, + const struct reftable_log_record *b, int hash_size); + +/* dumps a reftable_log_record on stdout, for debugging/testing. */ +void reftable_log_record_print(struct reftable_log_record *log, + uint32_t hash_id); + +#endif diff --git a/reftable/reftable-stack.h b/reftable/reftable-stack.h new file mode 100644 index 0000000000..1b602dda58 --- /dev/null +++ b/reftable/reftable-stack.h @@ -0,0 +1,128 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_STACK_H +#define REFTABLE_STACK_H + +#include "reftable-writer.h" + +/* + * The stack presents an interface to a mutable sequence of reftables. + + * A stack can be mutated by pushing a table to the top of the stack. + + * The reftable_stack automatically compacts files on disk to ensure good + * amortized performance. + * + * For windows and other platforms that cannot have open files as rename + * destinations, concurrent access from multiple processes needs the rand() + * random seed to be randomized. + */ +struct reftable_stack; + +/* open a new reftable stack. The tables along with the table list will be + * stored in 'dir'. Typically, this should be .git/reftables. + */ +int reftable_new_stack(struct reftable_stack **dest, const char *dir, + struct reftable_write_options config); + +/* returns the update_index at which a next table should be written. */ +uint64_t reftable_stack_next_update_index(struct reftable_stack *st); + +/* holds a transaction to add tables at the top of a stack. */ +struct reftable_addition; + +/* + * returns a new transaction to add reftables to the given stack. As a side + * effect, the ref database is locked. + */ +int reftable_stack_new_addition(struct reftable_addition **dest, + struct reftable_stack *st); + +/* Adds a reftable to transaction. */ +int reftable_addition_add(struct reftable_addition *add, + int (*write_table)(struct reftable_writer *wr, + void *arg), + void *arg); + +/* Commits the transaction, releasing the lock. After calling this, + * reftable_addition_destroy should still be called. + */ +int reftable_addition_commit(struct reftable_addition *add); + +/* Release all non-committed data from the transaction, and deallocate the + * transaction. Releases the lock if held. */ +void reftable_addition_destroy(struct reftable_addition *add); + +/* add a new table to the stack. The write_table function must call + * reftable_writer_set_limits, add refs and return an error value. */ +int reftable_stack_add(struct reftable_stack *st, + int (*write_table)(struct reftable_writer *wr, + void *write_arg), + void *write_arg); + +/* returns the merged_table for seeking. This table is valid until the + * next write or reload, and should not be closed or deleted. + */ +struct reftable_merged_table * +reftable_stack_merged_table(struct reftable_stack *st); + +/* frees all resources associated with the stack. */ +void reftable_stack_destroy(struct reftable_stack *st); + +/* Reloads the stack if necessary. This is very cheap to run if the stack was up + * to date */ +int reftable_stack_reload(struct reftable_stack *st); + +/* Policy for expiring reflog entries. */ +struct reftable_log_expiry_config { + /* Drop entries older than this timestamp */ + uint64_t time; + + /* Drop older entries */ + uint64_t min_update_index; +}; + +/* compacts all reftables into a giant table. Expire reflog entries if config is + * non-NULL */ +int reftable_stack_compact_all(struct reftable_stack *st, + struct reftable_log_expiry_config *config); + +/* heuristically compact unbalanced table stack. */ +int reftable_stack_auto_compact(struct reftable_stack *st); + +/* delete stale .ref tables. */ +int reftable_stack_clean(struct reftable_stack *st); + +/* convenience function to read a single ref. Returns < 0 for error, 0 for + * success, and 1 if ref not found. */ +int reftable_stack_read_ref(struct reftable_stack *st, const char *refname, + struct reftable_ref_record *ref); + +/* convenience function to read a single log. Returns < 0 for error, 0 for + * success, and 1 if ref not found. */ +int reftable_stack_read_log(struct reftable_stack *st, const char *refname, + struct reftable_log_record *log); + +/* statistics on past compactions. */ +struct reftable_compaction_stats { + uint64_t bytes; /* total number of bytes written */ + uint64_t entries_written; /* total number of entries written, including + failures. */ + int attempts; /* how often we tried to compact */ + int failures; /* failures happen on concurrent updates */ +}; + +/* return statistics for compaction up till now. */ +struct reftable_compaction_stats * +reftable_stack_compaction_stats(struct reftable_stack *st); + +/* print the entire stack represented by the directory */ +int reftable_stack_print_directory(const char *stackdir, uint32_t hash_id); + +#endif diff --git a/reftable/reftable-tests.h b/reftable/reftable-tests.h new file mode 100644 index 0000000000..0019cbcfa4 --- /dev/null +++ b/reftable/reftable-tests.h @@ -0,0 +1,23 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_TESTS_H +#define REFTABLE_TESTS_H + +int basics_test_main(int argc, const char **argv); +int block_test_main(int argc, const char **argv); +int merged_test_main(int argc, const char **argv); +int pq_test_main(int argc, const char **argv); +int record_test_main(int argc, const char **argv); +int refname_test_main(int argc, const char **argv); +int readwrite_test_main(int argc, const char **argv); +int stack_test_main(int argc, const char **argv); +int tree_test_main(int argc, const char **argv); +int reftable_dump_main(int argc, char *const *argv); + +#endif diff --git a/reftable/reftable-writer.h b/reftable/reftable-writer.h new file mode 100644 index 0000000000..db8de197f6 --- /dev/null +++ b/reftable/reftable-writer.h @@ -0,0 +1,151 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_WRITER_H +#define REFTABLE_WRITER_H + +#include "reftable-record.h" + +#include <stdint.h> +#include <unistd.h> /* ssize_t */ + +/* Writing single reftables */ + +/* reftable_write_options sets options for writing a single reftable. */ +struct reftable_write_options { + /* boolean: do not pad out blocks to block size. */ + unsigned unpadded : 1; + + /* the blocksize. Should be less than 2^24. */ + uint32_t block_size; + + /* boolean: do not generate a SHA1 => ref index. */ + unsigned skip_index_objects : 1; + + /* how often to write complete keys in each block. */ + int restart_interval; + + /* 4-byte identifier ("sha1", "s256") of the hash. + * Defaults to SHA1 if unset + */ + uint32_t hash_id; + + /* Default mode for creating files. If unset, use 0666 (+umask) */ + unsigned int default_permissions; + + /* boolean: do not check ref names for validity or dir/file conflicts. + */ + unsigned skip_name_check : 1; + + /* boolean: copy log messages exactly. If unset, check that the message + * is a single line, and add '\n' if missing. + */ + unsigned exact_log_message : 1; +}; + +/* reftable_block_stats holds statistics for a single block type */ +struct reftable_block_stats { + /* total number of entries written */ + int entries; + /* total number of key restarts */ + int restarts; + /* total number of blocks */ + int blocks; + /* total number of index blocks */ + int index_blocks; + /* depth of the index */ + int max_index_level; + + /* offset of the first block for this type */ + uint64_t offset; + /* offset of the top level index block for this type, or 0 if not + * present */ + uint64_t index_offset; +}; + +/* stats holds overall statistics for a single reftable */ +struct reftable_stats { + /* total number of blocks written. */ + int blocks; + /* stats for ref data */ + struct reftable_block_stats ref_stats; + /* stats for the SHA1 to ref map. */ + struct reftable_block_stats obj_stats; + /* stats for index blocks */ + struct reftable_block_stats idx_stats; + /* stats for log blocks */ + struct reftable_block_stats log_stats; + + /* disambiguation length of shortened object IDs. */ + int object_id_len; +}; + +/* reftable_new_writer creates a new writer */ +struct reftable_writer * +reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t), + void *writer_arg, struct reftable_write_options *opts); + +/* Set the range of update indices for the records we will add. When writing a + table into a stack, the min should be at least + reftable_stack_next_update_index(), or REFTABLE_API_ERROR is returned. + + For transactional updates to a stack, typically min==max, and the + update_index can be obtained by inspeciting the stack. When converting an + existing ref database into a single reftable, this would be a range of + update-index timestamps. + */ +void reftable_writer_set_limits(struct reftable_writer *w, uint64_t min, + uint64_t max); + +/* + Add a reftable_ref_record. The record should have names that come after + already added records. + + The update_index must be within the limits set by + reftable_writer_set_limits(), or REFTABLE_API_ERROR is returned. It is an + REFTABLE_API_ERROR error to write a ref record after a log record. +*/ +int reftable_writer_add_ref(struct reftable_writer *w, + struct reftable_ref_record *ref); + +/* + Convenience function to add multiple reftable_ref_records; the function sorts + the records before adding them, reordering the records array passed in. +*/ +int reftable_writer_add_refs(struct reftable_writer *w, + struct reftable_ref_record *refs, int n); + +/* + adds reftable_log_records. Log records are keyed by (refname, decreasing + update_index). The key for the record added must come after the already added + log records. +*/ +int reftable_writer_add_log(struct reftable_writer *w, + struct reftable_log_record *log); + +/* + Convenience function to add multiple reftable_log_records; the function sorts + the records before adding them, reordering records array passed in. +*/ +int reftable_writer_add_logs(struct reftable_writer *w, + struct reftable_log_record *logs, int n); + +/* reftable_writer_close finalizes the reftable. The writer is retained so + * statistics can be inspected. */ +int reftable_writer_close(struct reftable_writer *w); + +/* writer_stats returns the statistics on the reftable being written. + + This struct becomes invalid when the writer is freed. + */ +const struct reftable_stats *reftable_writer_stats(struct reftable_writer *w); + +/* reftable_writer_free deallocates memory for the writer */ +void reftable_writer_free(struct reftable_writer *w); + +#endif diff --git a/reftable/stack.c b/reftable/stack.c new file mode 100644 index 0000000000..ddbdf1b9c8 --- /dev/null +++ b/reftable/stack.c @@ -0,0 +1,1414 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "stack.h" + +#include "system.h" +#include "merged.h" +#include "reader.h" +#include "refname.h" +#include "reftable-error.h" +#include "reftable-record.h" +#include "reftable-merged.h" +#include "writer.h" + +static int stack_try_add(struct reftable_stack *st, + int (*write_table)(struct reftable_writer *wr, + void *arg), + void *arg); +static int stack_write_compact(struct reftable_stack *st, + struct reftable_writer *wr, int first, int last, + struct reftable_log_expiry_config *config); +static int stack_check_addition(struct reftable_stack *st, + const char *new_tab_name); +static void reftable_addition_close(struct reftable_addition *add); +static int reftable_stack_reload_maybe_reuse(struct reftable_stack *st, + int reuse_open); + +static void stack_filename(struct strbuf *dest, struct reftable_stack *st, + const char *name) +{ + strbuf_reset(dest); + strbuf_addstr(dest, st->reftable_dir); + strbuf_addstr(dest, "/"); + strbuf_addstr(dest, name); +} + +static ssize_t reftable_fd_write(void *arg, const void *data, size_t sz) +{ + int *fdp = (int *)arg; + return write(*fdp, data, sz); +} + +int reftable_new_stack(struct reftable_stack **dest, const char *dir, + struct reftable_write_options config) +{ + struct reftable_stack *p = + reftable_calloc(sizeof(struct reftable_stack)); + struct strbuf list_file_name = STRBUF_INIT; + int err = 0; + + if (config.hash_id == 0) { + config.hash_id = GIT_SHA1_FORMAT_ID; + } + + *dest = NULL; + + strbuf_reset(&list_file_name); + strbuf_addstr(&list_file_name, dir); + strbuf_addstr(&list_file_name, "/tables.list"); + + p->list_file = strbuf_detach(&list_file_name, NULL); + p->reftable_dir = xstrdup(dir); + p->config = config; + + err = reftable_stack_reload_maybe_reuse(p, 1); + if (err < 0) { + reftable_stack_destroy(p); + } else { + *dest = p; + } + return err; +} + +static int fd_read_lines(int fd, char ***namesp) +{ + off_t size = lseek(fd, 0, SEEK_END); + char *buf = NULL; + int err = 0; + if (size < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + err = lseek(fd, 0, SEEK_SET); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + buf = reftable_malloc(size + 1); + if (read(fd, buf, size) != size) { + err = REFTABLE_IO_ERROR; + goto done; + } + buf[size] = 0; + + parse_names(buf, size, namesp); + +done: + reftable_free(buf); + return err; +} + +int read_lines(const char *filename, char ***namesp) +{ + int fd = open(filename, O_RDONLY); + int err = 0; + if (fd < 0) { + if (errno == ENOENT) { + *namesp = reftable_calloc(sizeof(char *)); + return 0; + } + + return REFTABLE_IO_ERROR; + } + err = fd_read_lines(fd, namesp); + close(fd); + return err; +} + +struct reftable_merged_table * +reftable_stack_merged_table(struct reftable_stack *st) +{ + return st->merged; +} + +static int has_name(char **names, const char *name) +{ + while (*names) { + if (!strcmp(*names, name)) + return 1; + names++; + } + return 0; +} + +/* Close and free the stack */ +void reftable_stack_destroy(struct reftable_stack *st) +{ + char **names = NULL; + int err = 0; + if (st->merged) { + reftable_merged_table_free(st->merged); + st->merged = NULL; + } + + err = read_lines(st->list_file, &names); + if (err < 0) { + FREE_AND_NULL(names); + } + + if (st->readers) { + int i = 0; + struct strbuf filename = STRBUF_INIT; + for (i = 0; i < st->readers_len; i++) { + const char *name = reader_name(st->readers[i]); + strbuf_reset(&filename); + if (names && !has_name(names, name)) { + stack_filename(&filename, st, name); + } + reftable_reader_free(st->readers[i]); + + if (filename.len) { + /* On Windows, can only unlink after closing. */ + unlink(filename.buf); + } + } + strbuf_release(&filename); + st->readers_len = 0; + FREE_AND_NULL(st->readers); + } + FREE_AND_NULL(st->list_file); + FREE_AND_NULL(st->reftable_dir); + reftable_free(st); + free_names(names); +} + +static struct reftable_reader **stack_copy_readers(struct reftable_stack *st, + int cur_len) +{ + struct reftable_reader **cur = + reftable_calloc(sizeof(struct reftable_reader *) * cur_len); + int i = 0; + for (i = 0; i < cur_len; i++) { + cur[i] = st->readers[i]; + } + return cur; +} + +static int reftable_stack_reload_once(struct reftable_stack *st, char **names, + int reuse_open) +{ + int cur_len = !st->merged ? 0 : st->merged->stack_len; + struct reftable_reader **cur = stack_copy_readers(st, cur_len); + int err = 0; + int names_len = names_length(names); + struct reftable_reader **new_readers = + reftable_calloc(sizeof(struct reftable_reader *) * names_len); + struct reftable_table *new_tables = + reftable_calloc(sizeof(struct reftable_table) * names_len); + int new_readers_len = 0; + struct reftable_merged_table *new_merged = NULL; + int i; + + while (*names) { + struct reftable_reader *rd = NULL; + char *name = *names++; + + /* this is linear; we assume compaction keeps the number of + tables under control so this is not quadratic. */ + int j = 0; + for (j = 0; reuse_open && j < cur_len; j++) { + if (cur[j] && 0 == strcmp(cur[j]->name, name)) { + rd = cur[j]; + cur[j] = NULL; + break; + } + } + + if (!rd) { + struct reftable_block_source src = { NULL }; + struct strbuf table_path = STRBUF_INIT; + stack_filename(&table_path, st, name); + + err = reftable_block_source_from_file(&src, + table_path.buf); + strbuf_release(&table_path); + + if (err < 0) + goto done; + + err = reftable_new_reader(&rd, &src, name); + if (err < 0) + goto done; + } + + new_readers[new_readers_len] = rd; + reftable_table_from_reader(&new_tables[new_readers_len], rd); + new_readers_len++; + } + + /* success! */ + err = reftable_new_merged_table(&new_merged, new_tables, + new_readers_len, st->config.hash_id); + if (err < 0) + goto done; + + new_tables = NULL; + st->readers_len = new_readers_len; + if (st->merged) { + merged_table_release(st->merged); + reftable_merged_table_free(st->merged); + } + if (st->readers) { + reftable_free(st->readers); + } + st->readers = new_readers; + new_readers = NULL; + new_readers_len = 0; + + new_merged->suppress_deletions = 1; + st->merged = new_merged; + for (i = 0; i < cur_len; i++) { + if (cur[i]) { + const char *name = reader_name(cur[i]); + struct strbuf filename = STRBUF_INIT; + stack_filename(&filename, st, name); + + reader_close(cur[i]); + reftable_reader_free(cur[i]); + + /* On Windows, can only unlink after closing. */ + unlink(filename.buf); + + strbuf_release(&filename); + } + } + +done: + for (i = 0; i < new_readers_len; i++) { + reader_close(new_readers[i]); + reftable_reader_free(new_readers[i]); + } + reftable_free(new_readers); + reftable_free(new_tables); + reftable_free(cur); + return err; +} + +/* return negative if a before b. */ +static int tv_cmp(struct timeval *a, struct timeval *b) +{ + time_t diff = a->tv_sec - b->tv_sec; + int udiff = a->tv_usec - b->tv_usec; + + if (diff != 0) + return diff; + + return udiff; +} + +static int reftable_stack_reload_maybe_reuse(struct reftable_stack *st, + int reuse_open) +{ + struct timeval deadline = { 0 }; + int err = gettimeofday(&deadline, NULL); + int64_t delay = 0; + int tries = 0; + if (err < 0) + return err; + + deadline.tv_sec += 3; + while (1) { + char **names = NULL; + char **names_after = NULL; + struct timeval now = { 0 }; + int err = gettimeofday(&now, NULL); + int err2 = 0; + if (err < 0) { + return err; + } + + /* Only look at deadlines after the first few times. This + simplifies debugging in GDB */ + tries++; + if (tries > 3 && tv_cmp(&now, &deadline) >= 0) { + break; + } + + err = read_lines(st->list_file, &names); + if (err < 0) { + free_names(names); + return err; + } + err = reftable_stack_reload_once(st, names, reuse_open); + if (err == 0) { + free_names(names); + break; + } + if (err != REFTABLE_NOT_EXIST_ERROR) { + free_names(names); + return err; + } + + /* err == REFTABLE_NOT_EXIST_ERROR can be caused by a concurrent + writer. Check if there was one by checking if the name list + changed. + */ + err2 = read_lines(st->list_file, &names_after); + if (err2 < 0) { + free_names(names); + return err2; + } + + if (names_equal(names_after, names)) { + free_names(names); + free_names(names_after); + return err; + } + free_names(names); + free_names(names_after); + + delay = delay + (delay * rand()) / RAND_MAX + 1; + sleep_millisec(delay); + } + + return 0; +} + +/* -1 = error + 0 = up to date + 1 = changed. */ +static int stack_uptodate(struct reftable_stack *st) +{ + char **names = NULL; + int err = read_lines(st->list_file, &names); + int i = 0; + if (err < 0) + return err; + + for (i = 0; i < st->readers_len; i++) { + if (!names[i]) { + err = 1; + goto done; + } + + if (strcmp(st->readers[i]->name, names[i])) { + err = 1; + goto done; + } + } + + if (names[st->merged->stack_len]) { + err = 1; + goto done; + } + +done: + free_names(names); + return err; +} + +int reftable_stack_reload(struct reftable_stack *st) +{ + int err = stack_uptodate(st); + if (err > 0) + return reftable_stack_reload_maybe_reuse(st, 1); + return err; +} + +int reftable_stack_add(struct reftable_stack *st, + int (*write)(struct reftable_writer *wr, void *arg), + void *arg) +{ + int err = stack_try_add(st, write, arg); + if (err < 0) { + if (err == REFTABLE_LOCK_ERROR) { + /* Ignore error return, we want to propagate + REFTABLE_LOCK_ERROR. + */ + reftable_stack_reload(st); + } + return err; + } + + if (!st->disable_auto_compact) + return reftable_stack_auto_compact(st); + + return 0; +} + +static void format_name(struct strbuf *dest, uint64_t min, uint64_t max) +{ + char buf[100]; + uint32_t rnd = (uint32_t)rand(); + snprintf(buf, sizeof(buf), "0x%012" PRIx64 "-0x%012" PRIx64 "-%08x", + min, max, rnd); + strbuf_reset(dest); + strbuf_addstr(dest, buf); +} + +struct reftable_addition { + int lock_file_fd; + struct strbuf lock_file_name; + struct reftable_stack *stack; + + char **new_tables; + int new_tables_len; + uint64_t next_update_index; +}; + +#define REFTABLE_ADDITION_INIT \ + { \ + .lock_file_name = STRBUF_INIT \ + } + +static int reftable_stack_init_addition(struct reftable_addition *add, + struct reftable_stack *st) +{ + int err = 0; + add->stack = st; + + strbuf_reset(&add->lock_file_name); + strbuf_addstr(&add->lock_file_name, st->list_file); + strbuf_addstr(&add->lock_file_name, ".lock"); + + add->lock_file_fd = open(add->lock_file_name.buf, + O_EXCL | O_CREAT | O_WRONLY, 0666); + if (add->lock_file_fd < 0) { + if (errno == EEXIST) { + err = REFTABLE_LOCK_ERROR; + } else { + err = REFTABLE_IO_ERROR; + } + goto done; + } + if (st->config.default_permissions) { + if (chmod(add->lock_file_name.buf, st->config.default_permissions) < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + } + + err = stack_uptodate(st); + if (err < 0) + goto done; + + if (err > 1) { + err = REFTABLE_LOCK_ERROR; + goto done; + } + + add->next_update_index = reftable_stack_next_update_index(st); +done: + if (err) { + reftable_addition_close(add); + } + return err; +} + +static void reftable_addition_close(struct reftable_addition *add) +{ + int i = 0; + struct strbuf nm = STRBUF_INIT; + for (i = 0; i < add->new_tables_len; i++) { + stack_filename(&nm, add->stack, add->new_tables[i]); + unlink(nm.buf); + reftable_free(add->new_tables[i]); + add->new_tables[i] = NULL; + } + reftable_free(add->new_tables); + add->new_tables = NULL; + add->new_tables_len = 0; + + if (add->lock_file_fd > 0) { + close(add->lock_file_fd); + add->lock_file_fd = 0; + } + if (add->lock_file_name.len > 0) { + unlink(add->lock_file_name.buf); + strbuf_release(&add->lock_file_name); + } + + strbuf_release(&nm); +} + +void reftable_addition_destroy(struct reftable_addition *add) +{ + if (!add) { + return; + } + reftable_addition_close(add); + reftable_free(add); +} + +int reftable_addition_commit(struct reftable_addition *add) +{ + struct strbuf table_list = STRBUF_INIT; + int i = 0; + int err = 0; + if (add->new_tables_len == 0) + goto done; + + for (i = 0; i < add->stack->merged->stack_len; i++) { + strbuf_addstr(&table_list, add->stack->readers[i]->name); + strbuf_addstr(&table_list, "\n"); + } + for (i = 0; i < add->new_tables_len; i++) { + strbuf_addstr(&table_list, add->new_tables[i]); + strbuf_addstr(&table_list, "\n"); + } + + err = write(add->lock_file_fd, table_list.buf, table_list.len); + strbuf_release(&table_list); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = close(add->lock_file_fd); + add->lock_file_fd = 0; + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = rename(add->lock_file_name.buf, add->stack->list_file); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + /* success, no more state to clean up. */ + strbuf_release(&add->lock_file_name); + for (i = 0; i < add->new_tables_len; i++) { + reftable_free(add->new_tables[i]); + } + reftable_free(add->new_tables); + add->new_tables = NULL; + add->new_tables_len = 0; + + err = reftable_stack_reload(add->stack); +done: + reftable_addition_close(add); + return err; +} + +int reftable_stack_new_addition(struct reftable_addition **dest, + struct reftable_stack *st) +{ + int err = 0; + struct reftable_addition empty = REFTABLE_ADDITION_INIT; + *dest = reftable_calloc(sizeof(**dest)); + **dest = empty; + err = reftable_stack_init_addition(*dest, st); + if (err) { + reftable_free(*dest); + *dest = NULL; + } + return err; +} + +static int stack_try_add(struct reftable_stack *st, + int (*write_table)(struct reftable_writer *wr, + void *arg), + void *arg) +{ + struct reftable_addition add = REFTABLE_ADDITION_INIT; + int err = reftable_stack_init_addition(&add, st); + if (err < 0) + goto done; + if (err > 0) { + err = REFTABLE_LOCK_ERROR; + goto done; + } + + err = reftable_addition_add(&add, write_table, arg); + if (err < 0) + goto done; + + err = reftable_addition_commit(&add); +done: + reftable_addition_close(&add); + return err; +} + +int reftable_addition_add(struct reftable_addition *add, + int (*write_table)(struct reftable_writer *wr, + void *arg), + void *arg) +{ + struct strbuf temp_tab_file_name = STRBUF_INIT; + struct strbuf tab_file_name = STRBUF_INIT; + struct strbuf next_name = STRBUF_INIT; + struct reftable_writer *wr = NULL; + int err = 0; + int tab_fd = 0; + + strbuf_reset(&next_name); + format_name(&next_name, add->next_update_index, add->next_update_index); + + stack_filename(&temp_tab_file_name, add->stack, next_name.buf); + strbuf_addstr(&temp_tab_file_name, ".temp.XXXXXX"); + + tab_fd = mkstemp(temp_tab_file_name.buf); + if (tab_fd < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + if (add->stack->config.default_permissions) { + if (chmod(temp_tab_file_name.buf, add->stack->config.default_permissions)) { + err = REFTABLE_IO_ERROR; + goto done; + } + } + wr = reftable_new_writer(reftable_fd_write, &tab_fd, + &add->stack->config); + err = write_table(wr, arg); + if (err < 0) + goto done; + + err = reftable_writer_close(wr); + if (err == REFTABLE_EMPTY_TABLE_ERROR) { + err = 0; + goto done; + } + if (err < 0) + goto done; + + err = close(tab_fd); + tab_fd = 0; + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = stack_check_addition(add->stack, temp_tab_file_name.buf); + if (err < 0) + goto done; + + if (wr->min_update_index < add->next_update_index) { + err = REFTABLE_API_ERROR; + goto done; + } + + format_name(&next_name, wr->min_update_index, wr->max_update_index); + strbuf_addstr(&next_name, ".ref"); + + stack_filename(&tab_file_name, add->stack, next_name.buf); + + /* + On windows, this relies on rand() picking a unique destination name. + Maybe we should do retry loop as well? + */ + err = rename(temp_tab_file_name.buf, tab_file_name.buf); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + add->new_tables = reftable_realloc(add->new_tables, + sizeof(*add->new_tables) * + (add->new_tables_len + 1)); + add->new_tables[add->new_tables_len] = strbuf_detach(&next_name, NULL); + add->new_tables_len++; +done: + if (tab_fd > 0) { + close(tab_fd); + tab_fd = 0; + } + if (temp_tab_file_name.len > 0) { + unlink(temp_tab_file_name.buf); + } + + strbuf_release(&temp_tab_file_name); + strbuf_release(&tab_file_name); + strbuf_release(&next_name); + reftable_writer_free(wr); + return err; +} + +uint64_t reftable_stack_next_update_index(struct reftable_stack *st) +{ + int sz = st->merged->stack_len; + if (sz > 0) + return reftable_reader_max_update_index(st->readers[sz - 1]) + + 1; + return 1; +} + +static int stack_compact_locked(struct reftable_stack *st, int first, int last, + struct strbuf *temp_tab, + struct reftable_log_expiry_config *config) +{ + struct strbuf next_name = STRBUF_INIT; + int tab_fd = -1; + struct reftable_writer *wr = NULL; + int err = 0; + + format_name(&next_name, + reftable_reader_min_update_index(st->readers[first]), + reftable_reader_max_update_index(st->readers[last])); + + stack_filename(temp_tab, st, next_name.buf); + strbuf_addstr(temp_tab, ".temp.XXXXXX"); + + tab_fd = mkstemp(temp_tab->buf); + wr = reftable_new_writer(reftable_fd_write, &tab_fd, &st->config); + + err = stack_write_compact(st, wr, first, last, config); + if (err < 0) + goto done; + err = reftable_writer_close(wr); + if (err < 0) + goto done; + + err = close(tab_fd); + tab_fd = 0; + +done: + reftable_writer_free(wr); + if (tab_fd > 0) { + close(tab_fd); + tab_fd = 0; + } + if (err != 0 && temp_tab->len > 0) { + unlink(temp_tab->buf); + strbuf_release(temp_tab); + } + strbuf_release(&next_name); + return err; +} + +static int stack_write_compact(struct reftable_stack *st, + struct reftable_writer *wr, int first, int last, + struct reftable_log_expiry_config *config) +{ + int subtabs_len = last - first + 1; + struct reftable_table *subtabs = reftable_calloc( + sizeof(struct reftable_table) * (last - first + 1)); + struct reftable_merged_table *mt = NULL; + int err = 0; + struct reftable_iterator it = { NULL }; + struct reftable_ref_record ref = { NULL }; + struct reftable_log_record log = { NULL }; + + uint64_t entries = 0; + + int i = 0, j = 0; + for (i = first, j = 0; i <= last; i++) { + struct reftable_reader *t = st->readers[i]; + reftable_table_from_reader(&subtabs[j++], t); + st->stats.bytes += t->size; + } + reftable_writer_set_limits(wr, st->readers[first]->min_update_index, + st->readers[last]->max_update_index); + + err = reftable_new_merged_table(&mt, subtabs, subtabs_len, + st->config.hash_id); + if (err < 0) { + reftable_free(subtabs); + goto done; + } + + err = reftable_merged_table_seek_ref(mt, &it, ""); + if (err < 0) + goto done; + + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + err = 0; + break; + } + if (err < 0) { + break; + } + + if (first == 0 && reftable_ref_record_is_deletion(&ref)) { + continue; + } + + err = reftable_writer_add_ref(wr, &ref); + if (err < 0) { + break; + } + entries++; + } + reftable_iterator_destroy(&it); + + err = reftable_merged_table_seek_log(mt, &it, ""); + if (err < 0) + goto done; + + while (1) { + err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + err = 0; + break; + } + if (err < 0) { + break; + } + if (first == 0 && reftable_log_record_is_deletion(&log)) { + continue; + } + + if (config && config->min_update_index > 0 && + log.update_index < config->min_update_index) { + continue; + } + + if (config && config->time > 0 && + log.value.update.time < config->time) { + continue; + } + + err = reftable_writer_add_log(wr, &log); + if (err < 0) { + break; + } + entries++; + } + +done: + reftable_iterator_destroy(&it); + if (mt) { + merged_table_release(mt); + reftable_merged_table_free(mt); + } + reftable_ref_record_release(&ref); + reftable_log_record_release(&log); + st->stats.entries_written += entries; + return err; +} + +/* < 0: error. 0 == OK, > 0 attempt failed; could retry. */ +static int stack_compact_range(struct reftable_stack *st, int first, int last, + struct reftable_log_expiry_config *expiry) +{ + struct strbuf temp_tab_file_name = STRBUF_INIT; + struct strbuf new_table_name = STRBUF_INIT; + struct strbuf lock_file_name = STRBUF_INIT; + struct strbuf ref_list_contents = STRBUF_INIT; + struct strbuf new_table_path = STRBUF_INIT; + int err = 0; + int have_lock = 0; + int lock_file_fd = -1; + int compact_count = last - first + 1; + char **listp = NULL; + char **delete_on_success = + reftable_calloc(sizeof(char *) * (compact_count + 1)); + char **subtable_locks = + reftable_calloc(sizeof(char *) * (compact_count + 1)); + int i = 0; + int j = 0; + int is_empty_table = 0; + + if (first > last || (!expiry && first == last)) { + err = 0; + goto done; + } + + st->stats.attempts++; + + strbuf_reset(&lock_file_name); + strbuf_addstr(&lock_file_name, st->list_file); + strbuf_addstr(&lock_file_name, ".lock"); + + lock_file_fd = + open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0666); + if (lock_file_fd < 0) { + if (errno == EEXIST) { + err = 1; + } else { + err = REFTABLE_IO_ERROR; + } + goto done; + } + /* Don't want to write to the lock for now. */ + close(lock_file_fd); + lock_file_fd = -1; + + have_lock = 1; + err = stack_uptodate(st); + if (err != 0) + goto done; + + for (i = first, j = 0; i <= last; i++) { + struct strbuf subtab_file_name = STRBUF_INIT; + struct strbuf subtab_lock = STRBUF_INIT; + int sublock_file_fd = -1; + + stack_filename(&subtab_file_name, st, + reader_name(st->readers[i])); + + strbuf_reset(&subtab_lock); + strbuf_addbuf(&subtab_lock, &subtab_file_name); + strbuf_addstr(&subtab_lock, ".lock"); + + sublock_file_fd = open(subtab_lock.buf, + O_EXCL | O_CREAT | O_WRONLY, 0666); + if (sublock_file_fd >= 0) { + close(sublock_file_fd); + } else if (sublock_file_fd < 0) { + if (errno == EEXIST) { + err = 1; + } else { + err = REFTABLE_IO_ERROR; + } + } + + subtable_locks[j] = subtab_lock.buf; + delete_on_success[j] = subtab_file_name.buf; + j++; + + if (err != 0) + goto done; + } + + err = unlink(lock_file_name.buf); + if (err < 0) + goto done; + have_lock = 0; + + err = stack_compact_locked(st, first, last, &temp_tab_file_name, + expiry); + /* Compaction + tombstones can create an empty table out of non-empty + * tables. */ + is_empty_table = (err == REFTABLE_EMPTY_TABLE_ERROR); + if (is_empty_table) { + err = 0; + } + if (err < 0) + goto done; + + lock_file_fd = + open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0666); + if (lock_file_fd < 0) { + if (errno == EEXIST) { + err = 1; + } else { + err = REFTABLE_IO_ERROR; + } + goto done; + } + have_lock = 1; + if (st->config.default_permissions) { + if (chmod(lock_file_name.buf, st->config.default_permissions) < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + } + + format_name(&new_table_name, st->readers[first]->min_update_index, + st->readers[last]->max_update_index); + strbuf_addstr(&new_table_name, ".ref"); + + stack_filename(&new_table_path, st, new_table_name.buf); + + if (!is_empty_table) { + /* retry? */ + err = rename(temp_tab_file_name.buf, new_table_path.buf); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + } + + for (i = 0; i < first; i++) { + strbuf_addstr(&ref_list_contents, st->readers[i]->name); + strbuf_addstr(&ref_list_contents, "\n"); + } + if (!is_empty_table) { + strbuf_addbuf(&ref_list_contents, &new_table_name); + strbuf_addstr(&ref_list_contents, "\n"); + } + for (i = last + 1; i < st->merged->stack_len; i++) { + strbuf_addstr(&ref_list_contents, st->readers[i]->name); + strbuf_addstr(&ref_list_contents, "\n"); + } + + err = write(lock_file_fd, ref_list_contents.buf, ref_list_contents.len); + if (err < 0) { + err = REFTABLE_IO_ERROR; + unlink(new_table_path.buf); + goto done; + } + err = close(lock_file_fd); + lock_file_fd = -1; + if (err < 0) { + err = REFTABLE_IO_ERROR; + unlink(new_table_path.buf); + goto done; + } + + err = rename(lock_file_name.buf, st->list_file); + if (err < 0) { + err = REFTABLE_IO_ERROR; + unlink(new_table_path.buf); + goto done; + } + have_lock = 0; + + /* Reload the stack before deleting. On windows, we can only delete the + files after we closed them. + */ + err = reftable_stack_reload_maybe_reuse(st, first < last); + + listp = delete_on_success; + while (*listp) { + if (strcmp(*listp, new_table_path.buf)) { + unlink(*listp); + } + listp++; + } + +done: + free_names(delete_on_success); + + listp = subtable_locks; + while (*listp) { + unlink(*listp); + listp++; + } + free_names(subtable_locks); + if (lock_file_fd >= 0) { + close(lock_file_fd); + lock_file_fd = -1; + } + if (have_lock) { + unlink(lock_file_name.buf); + } + strbuf_release(&new_table_name); + strbuf_release(&new_table_path); + strbuf_release(&ref_list_contents); + strbuf_release(&temp_tab_file_name); + strbuf_release(&lock_file_name); + return err; +} + +int reftable_stack_compact_all(struct reftable_stack *st, + struct reftable_log_expiry_config *config) +{ + return stack_compact_range(st, 0, st->merged->stack_len - 1, config); +} + +static int stack_compact_range_stats(struct reftable_stack *st, int first, + int last, + struct reftable_log_expiry_config *config) +{ + int err = stack_compact_range(st, first, last, config); + if (err > 0) { + st->stats.failures++; + } + return err; +} + +static int segment_size(struct segment *s) +{ + return s->end - s->start; +} + +int fastlog2(uint64_t sz) +{ + int l = 0; + if (sz == 0) + return 0; + for (; sz; sz /= 2) { + l++; + } + return l - 1; +} + +struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n) +{ + struct segment *segs = reftable_calloc(sizeof(struct segment) * n); + int next = 0; + struct segment cur = { 0 }; + int i = 0; + + if (n == 0) { + *seglen = 0; + return segs; + } + for (i = 0; i < n; i++) { + int log = fastlog2(sizes[i]); + if (cur.log != log && cur.bytes > 0) { + struct segment fresh = { + .start = i, + }; + + segs[next++] = cur; + cur = fresh; + } + + cur.log = log; + cur.end = i + 1; + cur.bytes += sizes[i]; + } + segs[next++] = cur; + *seglen = next; + return segs; +} + +struct segment suggest_compaction_segment(uint64_t *sizes, int n) +{ + int seglen = 0; + struct segment *segs = sizes_to_segments(&seglen, sizes, n); + struct segment min_seg = { + .log = 64, + }; + int i = 0; + for (i = 0; i < seglen; i++) { + if (segment_size(&segs[i]) == 1) { + continue; + } + + if (segs[i].log < min_seg.log) { + min_seg = segs[i]; + } + } + + while (min_seg.start > 0) { + int prev = min_seg.start - 1; + if (fastlog2(min_seg.bytes) < fastlog2(sizes[prev])) { + break; + } + + min_seg.start = prev; + min_seg.bytes += sizes[prev]; + } + + reftable_free(segs); + return min_seg; +} + +static uint64_t *stack_table_sizes_for_compaction(struct reftable_stack *st) +{ + uint64_t *sizes = + reftable_calloc(sizeof(uint64_t) * st->merged->stack_len); + int version = (st->config.hash_id == GIT_SHA1_FORMAT_ID) ? 1 : 2; + int overhead = header_size(version) - 1; + int i = 0; + for (i = 0; i < st->merged->stack_len; i++) { + sizes[i] = st->readers[i]->size - overhead; + } + return sizes; +} + +int reftable_stack_auto_compact(struct reftable_stack *st) +{ + uint64_t *sizes = stack_table_sizes_for_compaction(st); + struct segment seg = + suggest_compaction_segment(sizes, st->merged->stack_len); + reftable_free(sizes); + if (segment_size(&seg) > 0) + return stack_compact_range_stats(st, seg.start, seg.end - 1, + NULL); + + return 0; +} + +struct reftable_compaction_stats * +reftable_stack_compaction_stats(struct reftable_stack *st) +{ + return &st->stats; +} + +int reftable_stack_read_ref(struct reftable_stack *st, const char *refname, + struct reftable_ref_record *ref) +{ + struct reftable_table tab = { NULL }; + reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st)); + return reftable_table_read_ref(&tab, refname, ref); +} + +int reftable_stack_read_log(struct reftable_stack *st, const char *refname, + struct reftable_log_record *log) +{ + struct reftable_iterator it = { NULL }; + struct reftable_merged_table *mt = reftable_stack_merged_table(st); + int err = reftable_merged_table_seek_log(mt, &it, refname); + if (err) + goto done; + + err = reftable_iterator_next_log(&it, log); + if (err) + goto done; + + if (strcmp(log->refname, refname) || + reftable_log_record_is_deletion(log)) { + err = 1; + goto done; + } + +done: + if (err) { + reftable_log_record_release(log); + } + reftable_iterator_destroy(&it); + return err; +} + +static int stack_check_addition(struct reftable_stack *st, + const char *new_tab_name) +{ + int err = 0; + struct reftable_block_source src = { NULL }; + struct reftable_reader *rd = NULL; + struct reftable_table tab = { NULL }; + struct reftable_ref_record *refs = NULL; + struct reftable_iterator it = { NULL }; + int cap = 0; + int len = 0; + int i = 0; + + if (st->config.skip_name_check) + return 0; + + err = reftable_block_source_from_file(&src, new_tab_name); + if (err < 0) + goto done; + + err = reftable_new_reader(&rd, &src, new_tab_name); + if (err < 0) + goto done; + + err = reftable_reader_seek_ref(rd, &it, ""); + if (err > 0) { + err = 0; + goto done; + } + if (err < 0) + goto done; + + while (1) { + struct reftable_ref_record ref = { NULL }; + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) + goto done; + + if (len >= cap) { + cap = 2 * cap + 1; + refs = reftable_realloc(refs, cap * sizeof(refs[0])); + } + + refs[len++] = ref; + } + + reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st)); + + err = validate_ref_record_addition(tab, refs, len); + +done: + for (i = 0; i < len; i++) { + reftable_ref_record_release(&refs[i]); + } + + free(refs); + reftable_iterator_destroy(&it); + reftable_reader_free(rd); + return err; +} + +static int is_table_name(const char *s) +{ + const char *dot = strrchr(s, '.'); + return dot && !strcmp(dot, ".ref"); +} + +static void remove_maybe_stale_table(struct reftable_stack *st, uint64_t max, + const char *name) +{ + int err = 0; + uint64_t update_idx = 0; + struct reftable_block_source src = { NULL }; + struct reftable_reader *rd = NULL; + struct strbuf table_path = STRBUF_INIT; + stack_filename(&table_path, st, name); + + err = reftable_block_source_from_file(&src, table_path.buf); + if (err < 0) + goto done; + + err = reftable_new_reader(&rd, &src, name); + if (err < 0) + goto done; + + update_idx = reftable_reader_max_update_index(rd); + reftable_reader_free(rd); + + if (update_idx <= max) { + unlink(table_path.buf); + } +done: + strbuf_release(&table_path); +} + +static int reftable_stack_clean_locked(struct reftable_stack *st) +{ + uint64_t max = reftable_merged_table_max_update_index( + reftable_stack_merged_table(st)); + DIR *dir = opendir(st->reftable_dir); + struct dirent *d = NULL; + if (!dir) { + return REFTABLE_IO_ERROR; + } + + while ((d = readdir(dir))) { + int i = 0; + int found = 0; + if (!is_table_name(d->d_name)) + continue; + + for (i = 0; !found && i < st->readers_len; i++) { + found = !strcmp(reader_name(st->readers[i]), d->d_name); + } + if (found) + continue; + + remove_maybe_stale_table(st, max, d->d_name); + } + + closedir(dir); + return 0; +} + +int reftable_stack_clean(struct reftable_stack *st) +{ + struct reftable_addition *add = NULL; + int err = reftable_stack_new_addition(&add, st); + if (err < 0) { + goto done; + } + + err = reftable_stack_reload(st); + if (err < 0) { + goto done; + } + + err = reftable_stack_clean_locked(st); + +done: + reftable_addition_destroy(add); + return err; +} + +int reftable_stack_print_directory(const char *stackdir, uint32_t hash_id) +{ + struct reftable_stack *stack = NULL; + struct reftable_write_options cfg = { .hash_id = hash_id }; + struct reftable_merged_table *merged = NULL; + struct reftable_table table = { NULL }; + + int err = reftable_new_stack(&stack, stackdir, cfg); + if (err < 0) + goto done; + + merged = reftable_stack_merged_table(stack); + reftable_table_from_merged_table(&table, merged); + err = reftable_table_print(&table); +done: + if (stack) + reftable_stack_destroy(stack); + return err; +} diff --git a/reftable/stack.h b/reftable/stack.h new file mode 100644 index 0000000000..f57005846e --- /dev/null +++ b/reftable/stack.h @@ -0,0 +1,41 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef STACK_H +#define STACK_H + +#include "system.h" +#include "reftable-writer.h" +#include "reftable-stack.h" + +struct reftable_stack { + char *list_file; + char *reftable_dir; + int disable_auto_compact; + + struct reftable_write_options config; + + struct reftable_reader **readers; + size_t readers_len; + struct reftable_merged_table *merged; + struct reftable_compaction_stats stats; +}; + +int read_lines(const char *filename, char ***lines); + +struct segment { + int start, end; + int log; + uint64_t bytes; +}; + +int fastlog2(uint64_t sz); +struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n); +struct segment suggest_compaction_segment(uint64_t *sizes, int n); + +#endif diff --git a/reftable/stack_test.c b/reftable/stack_test.c new file mode 100644 index 0000000000..19fe4e2008 --- /dev/null +++ b/reftable/stack_test.c @@ -0,0 +1,979 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "stack.h" + +#include "system.h" + +#include "reftable-reader.h" +#include "merged.h" +#include "basics.h" +#include "constants.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-tests.h" +#include "reader.h" + +#include <sys/types.h> +#include <dirent.h> + +static void clear_dir(const char *dirname) +{ + struct strbuf path = STRBUF_INIT; + strbuf_addstr(&path, dirname); + remove_dir_recursively(&path, 0); + strbuf_release(&path); +} + +static int count_dir_entries(const char *dirname) +{ + DIR *dir = opendir(dirname); + int len = 0; + struct dirent *d; + if (dir == NULL) + return 0; + + while ((d = readdir(dir))) { + if (!strcmp(d->d_name, "..") || !strcmp(d->d_name, ".")) + continue; + len++; + } + closedir(dir); + return len; +} + +/* + * Work linenumber into the tempdir, so we can see which tests forget to + * cleanup. + */ +static char *get_tmp_template(int linenumber) +{ + const char *tmp = getenv("TMPDIR"); + static char template[1024]; + snprintf(template, sizeof(template) - 1, "%s/stack_test-%d.XXXXXX", + tmp ? tmp : "/tmp", linenumber); + return template; +} + +static char *get_tmp_dir(int linenumber) +{ + char *dir = get_tmp_template(linenumber); + EXPECT(mkdtemp(dir)); + return dir; +} + +static void test_read_file(void) +{ + char *fn = get_tmp_template(__LINE__); + int fd = mkstemp(fn); + char out[1024] = "line1\n\nline2\nline3"; + int n, err; + char **names = NULL; + char *want[] = { "line1", "line2", "line3" }; + int i = 0; + + EXPECT(fd > 0); + n = write(fd, out, strlen(out)); + EXPECT(n == strlen(out)); + err = close(fd); + EXPECT(err >= 0); + + err = read_lines(fn, &names); + EXPECT_ERR(err); + + for (i = 0; names[i]; i++) { + EXPECT(0 == strcmp(want[i], names[i])); + } + free_names(names); + (void) remove(fn); +} + +static void test_parse_names(void) +{ + char buf[] = "line\n"; + char **names = NULL; + parse_names(buf, strlen(buf), &names); + + EXPECT(NULL != names[0]); + EXPECT(0 == strcmp(names[0], "line")); + EXPECT(NULL == names[1]); + free_names(names); +} + +static void test_names_equal(void) +{ + char *a[] = { "a", "b", "c", NULL }; + char *b[] = { "a", "b", "d", NULL }; + char *c[] = { "a", "b", NULL }; + + EXPECT(names_equal(a, a)); + EXPECT(!names_equal(a, b)); + EXPECT(!names_equal(a, c)); +} + +static int write_test_ref(struct reftable_writer *wr, void *arg) +{ + struct reftable_ref_record *ref = arg; + reftable_writer_set_limits(wr, ref->update_index, ref->update_index); + return reftable_writer_add_ref(wr, ref); +} + +struct write_log_arg { + struct reftable_log_record *log; + uint64_t update_index; +}; + +static int write_test_log(struct reftable_writer *wr, void *arg) +{ + struct write_log_arg *wla = arg; + + reftable_writer_set_limits(wr, wla->update_index, wla->update_index); + return reftable_writer_add_log(wr, wla->log); +} + +static void test_reftable_stack_add_one(void) +{ + char *dir = get_tmp_dir(__LINE__); + struct strbuf scratch = STRBUF_INIT; + int mask = umask(002); + struct reftable_write_options cfg = { + .default_permissions = 0660, + }; + struct reftable_stack *st = NULL; + int err; + struct reftable_ref_record ref = { + .refname = "HEAD", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + struct reftable_ref_record dest = { NULL }; + struct stat stat_result = { 0 }; + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_add(st, &write_test_ref, &ref); + EXPECT_ERR(err); + + err = reftable_stack_read_ref(st, ref.refname, &dest); + EXPECT_ERR(err); + EXPECT(0 == strcmp("master", dest.value.symref)); + EXPECT(st->readers_len > 0); + + printf("testing print functionality:\n"); + err = reftable_stack_print_directory(dir, GIT_SHA1_FORMAT_ID); + EXPECT_ERR(err); + + err = reftable_stack_print_directory(dir, GIT_SHA256_FORMAT_ID); + EXPECT(err == REFTABLE_FORMAT_ERROR); + +#ifndef GIT_WINDOWS_NATIVE + strbuf_addstr(&scratch, dir); + strbuf_addstr(&scratch, "/tables.list"); + err = stat(scratch.buf, &stat_result); + EXPECT(!err); + EXPECT((stat_result.st_mode & 0777) == cfg.default_permissions); + + strbuf_reset(&scratch); + strbuf_addstr(&scratch, dir); + strbuf_addstr(&scratch, "/"); + /* do not try at home; not an external API for reftable. */ + strbuf_addstr(&scratch, st->readers[0]->name); + err = stat(scratch.buf, &stat_result); + EXPECT(!err); + EXPECT((stat_result.st_mode & 0777) == cfg.default_permissions); +#else + (void) stat_result; +#endif + + reftable_ref_record_release(&dest); + reftable_stack_destroy(st); + strbuf_release(&scratch); + clear_dir(dir); + umask(mask); +} + +static void test_reftable_stack_uptodate(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st1 = NULL; + struct reftable_stack *st2 = NULL; + char *dir = get_tmp_dir(__LINE__); + + int err; + struct reftable_ref_record ref1 = { + .refname = "HEAD", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + struct reftable_ref_record ref2 = { + .refname = "branch2", + .update_index = 2, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + + + /* simulate multi-process access to the same stack + by creating two stacks for the same directory. + */ + err = reftable_new_stack(&st1, dir, cfg); + EXPECT_ERR(err); + + err = reftable_new_stack(&st2, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_add(st1, &write_test_ref, &ref1); + EXPECT_ERR(err); + + err = reftable_stack_add(st2, &write_test_ref, &ref2); + EXPECT(err == REFTABLE_LOCK_ERROR); + + err = reftable_stack_reload(st2); + EXPECT_ERR(err); + + err = reftable_stack_add(st2, &write_test_ref, &ref2); + EXPECT_ERR(err); + reftable_stack_destroy(st1); + reftable_stack_destroy(st2); + clear_dir(dir); +} + +static void test_reftable_stack_transaction_api(void) +{ + char *dir = get_tmp_dir(__LINE__); + + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_addition *add = NULL; + + struct reftable_ref_record ref = { + .refname = "HEAD", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + struct reftable_ref_record dest = { NULL }; + + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + reftable_addition_destroy(add); + + err = reftable_stack_new_addition(&add, st); + EXPECT_ERR(err); + + err = reftable_addition_add(add, &write_test_ref, &ref); + EXPECT_ERR(err); + + err = reftable_addition_commit(add); + EXPECT_ERR(err); + + reftable_addition_destroy(add); + + err = reftable_stack_read_ref(st, ref.refname, &dest); + EXPECT_ERR(err); + EXPECT(REFTABLE_REF_SYMREF == dest.value_type); + EXPECT(0 == strcmp("master", dest.value.symref)); + + reftable_ref_record_release(&dest); + reftable_stack_destroy(st); + clear_dir(dir); +} + +static void test_reftable_stack_validate_refname(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + char *dir = get_tmp_dir(__LINE__); + + int i; + struct reftable_ref_record ref = { + .refname = "a/b", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + char *additions[] = { "a", "a/b/c" }; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_add(st, &write_test_ref, &ref); + EXPECT_ERR(err); + + for (i = 0; i < ARRAY_SIZE(additions); i++) { + struct reftable_ref_record ref = { + .refname = additions[i], + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + + err = reftable_stack_add(st, &write_test_ref, &ref); + EXPECT(err == REFTABLE_NAME_CONFLICT); + } + + reftable_stack_destroy(st); + clear_dir(dir); +} + +static int write_error(struct reftable_writer *wr, void *arg) +{ + return *((int *)arg); +} + +static void test_reftable_stack_update_index_check(void) +{ + char *dir = get_tmp_dir(__LINE__); + + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_ref_record ref1 = { + .refname = "name1", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + struct reftable_ref_record ref2 = { + .refname = "name2", + .update_index = 1, + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_add(st, &write_test_ref, &ref1); + EXPECT_ERR(err); + + err = reftable_stack_add(st, &write_test_ref, &ref2); + EXPECT(err == REFTABLE_API_ERROR); + reftable_stack_destroy(st); + clear_dir(dir); +} + +static void test_reftable_stack_lock_failure(void) +{ + char *dir = get_tmp_dir(__LINE__); + + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err, i; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + for (i = -1; i != REFTABLE_EMPTY_TABLE_ERROR; i--) { + err = reftable_stack_add(st, &write_error, &i); + EXPECT(err == i); + } + + reftable_stack_destroy(st); + clear_dir(dir); +} + +static void test_reftable_stack_add(void) +{ + int i = 0; + int err = 0; + struct reftable_write_options cfg = { + .exact_log_message = 1, + }; + struct reftable_stack *st = NULL; + char *dir = get_tmp_dir(__LINE__); + + struct reftable_ref_record refs[2] = { { NULL } }; + struct reftable_log_record logs[2] = { { NULL } }; + int N = ARRAY_SIZE(refs); + + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + st->disable_auto_compact = 1; + + for (i = 0; i < N; i++) { + char buf[256]; + snprintf(buf, sizeof(buf), "branch%02d", i); + refs[i].refname = xstrdup(buf); + refs[i].update_index = i + 1; + refs[i].value_type = REFTABLE_REF_VAL1; + refs[i].value.val1 = reftable_malloc(GIT_SHA1_RAWSZ); + set_test_hash(refs[i].value.val1, i); + + logs[i].refname = xstrdup(buf); + logs[i].update_index = N + i + 1; + logs[i].value_type = REFTABLE_LOG_UPDATE; + + logs[i].value.update.new_hash = reftable_malloc(GIT_SHA1_RAWSZ); + logs[i].value.update.email = xstrdup("identity@invalid"); + set_test_hash(logs[i].value.update.new_hash, i); + } + + for (i = 0; i < N; i++) { + int err = reftable_stack_add(st, &write_test_ref, &refs[i]); + EXPECT_ERR(err); + } + + for (i = 0; i < N; i++) { + struct write_log_arg arg = { + .log = &logs[i], + .update_index = reftable_stack_next_update_index(st), + }; + int err = reftable_stack_add(st, &write_test_log, &arg); + EXPECT_ERR(err); + } + + err = reftable_stack_compact_all(st, NULL); + EXPECT_ERR(err); + + for (i = 0; i < N; i++) { + struct reftable_ref_record dest = { NULL }; + + int err = reftable_stack_read_ref(st, refs[i].refname, &dest); + EXPECT_ERR(err); + EXPECT(reftable_ref_record_equal(&dest, refs + i, + GIT_SHA1_RAWSZ)); + reftable_ref_record_release(&dest); + } + + for (i = 0; i < N; i++) { + struct reftable_log_record dest = { NULL }; + int err = reftable_stack_read_log(st, refs[i].refname, &dest); + EXPECT_ERR(err); + EXPECT(reftable_log_record_equal(&dest, logs + i, + GIT_SHA1_RAWSZ)); + reftable_log_record_release(&dest); + } + + /* cleanup */ + reftable_stack_destroy(st); + for (i = 0; i < N; i++) { + reftable_ref_record_release(&refs[i]); + reftable_log_record_release(&logs[i]); + } + clear_dir(dir); +} + +static void test_reftable_stack_log_normalize(void) +{ + int err = 0; + struct reftable_write_options cfg = { + 0, + }; + struct reftable_stack *st = NULL; + char *dir = get_tmp_dir(__LINE__); + + uint8_t h1[GIT_SHA1_RAWSZ] = { 0x01 }, h2[GIT_SHA1_RAWSZ] = { 0x02 }; + + struct reftable_log_record input = { .refname = "branch", + .update_index = 1, + .value_type = REFTABLE_LOG_UPDATE, + .value = { .update = { + .new_hash = h1, + .old_hash = h2, + } } }; + struct reftable_log_record dest = { + .update_index = 0, + }; + struct write_log_arg arg = { + .log = &input, + .update_index = 1, + }; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + input.value.update.message = "one\ntwo"; + err = reftable_stack_add(st, &write_test_log, &arg); + EXPECT(err == REFTABLE_API_ERROR); + + input.value.update.message = "one"; + err = reftable_stack_add(st, &write_test_log, &arg); + EXPECT_ERR(err); + + err = reftable_stack_read_log(st, input.refname, &dest); + EXPECT_ERR(err); + EXPECT(0 == strcmp(dest.value.update.message, "one\n")); + + input.value.update.message = "two\n"; + arg.update_index = 2; + err = reftable_stack_add(st, &write_test_log, &arg); + EXPECT_ERR(err); + err = reftable_stack_read_log(st, input.refname, &dest); + EXPECT_ERR(err); + EXPECT(0 == strcmp(dest.value.update.message, "two\n")); + + /* cleanup */ + reftable_stack_destroy(st); + reftable_log_record_release(&dest); + clear_dir(dir); +} + +static void test_reftable_stack_tombstone(void) +{ + int i = 0; + char *dir = get_tmp_dir(__LINE__); + + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_ref_record refs[2] = { { NULL } }; + struct reftable_log_record logs[2] = { { NULL } }; + int N = ARRAY_SIZE(refs); + struct reftable_ref_record dest = { NULL }; + struct reftable_log_record log_dest = { NULL }; + + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + /* even entries add the refs, odd entries delete them. */ + for (i = 0; i < N; i++) { + const char *buf = "branch"; + refs[i].refname = xstrdup(buf); + refs[i].update_index = i + 1; + if (i % 2 == 0) { + refs[i].value_type = REFTABLE_REF_VAL1; + refs[i].value.val1 = reftable_malloc(GIT_SHA1_RAWSZ); + set_test_hash(refs[i].value.val1, i); + } + + logs[i].refname = xstrdup(buf); + /* update_index is part of the key. */ + logs[i].update_index = 42; + if (i % 2 == 0) { + logs[i].value_type = REFTABLE_LOG_UPDATE; + logs[i].value.update.new_hash = + reftable_malloc(GIT_SHA1_RAWSZ); + set_test_hash(logs[i].value.update.new_hash, i); + logs[i].value.update.email = + xstrdup("identity@invalid"); + } + } + for (i = 0; i < N; i++) { + int err = reftable_stack_add(st, &write_test_ref, &refs[i]); + EXPECT_ERR(err); + } + + for (i = 0; i < N; i++) { + struct write_log_arg arg = { + .log = &logs[i], + .update_index = reftable_stack_next_update_index(st), + }; + int err = reftable_stack_add(st, &write_test_log, &arg); + EXPECT_ERR(err); + } + + err = reftable_stack_read_ref(st, "branch", &dest); + EXPECT(err == 1); + reftable_ref_record_release(&dest); + + err = reftable_stack_read_log(st, "branch", &log_dest); + EXPECT(err == 1); + reftable_log_record_release(&log_dest); + + err = reftable_stack_compact_all(st, NULL); + EXPECT_ERR(err); + + err = reftable_stack_read_ref(st, "branch", &dest); + EXPECT(err == 1); + + err = reftable_stack_read_log(st, "branch", &log_dest); + EXPECT(err == 1); + reftable_ref_record_release(&dest); + reftable_log_record_release(&log_dest); + + /* cleanup */ + reftable_stack_destroy(st); + for (i = 0; i < N; i++) { + reftable_ref_record_release(&refs[i]); + reftable_log_record_release(&logs[i]); + } + clear_dir(dir); +} + +static void test_reftable_stack_hash_id(void) +{ + char *dir = get_tmp_dir(__LINE__); + + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + + struct reftable_ref_record ref = { + .refname = "master", + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "target", + .update_index = 1, + }; + struct reftable_write_options cfg32 = { .hash_id = GIT_SHA256_FORMAT_ID }; + struct reftable_stack *st32 = NULL; + struct reftable_write_options cfg_default = { 0 }; + struct reftable_stack *st_default = NULL; + struct reftable_ref_record dest = { NULL }; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_add(st, &write_test_ref, &ref); + EXPECT_ERR(err); + + /* can't read it with the wrong hash ID. */ + err = reftable_new_stack(&st32, dir, cfg32); + EXPECT(err == REFTABLE_FORMAT_ERROR); + + /* check that we can read it back with default config too. */ + err = reftable_new_stack(&st_default, dir, cfg_default); + EXPECT_ERR(err); + + err = reftable_stack_read_ref(st_default, "master", &dest); + EXPECT_ERR(err); + + EXPECT(reftable_ref_record_equal(&ref, &dest, GIT_SHA1_RAWSZ)); + reftable_ref_record_release(&dest); + reftable_stack_destroy(st); + reftable_stack_destroy(st_default); + clear_dir(dir); +} + +static void test_log2(void) +{ + EXPECT(1 == fastlog2(3)); + EXPECT(2 == fastlog2(4)); + EXPECT(2 == fastlog2(5)); +} + +static void test_sizes_to_segments(void) +{ + uint64_t sizes[] = { 2, 3, 4, 5, 7, 9 }; + /* .................0 1 2 3 4 5 */ + + int seglen = 0; + struct segment *segs = + sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes)); + EXPECT(segs[2].log == 3); + EXPECT(segs[2].start == 5); + EXPECT(segs[2].end == 6); + + EXPECT(segs[1].log == 2); + EXPECT(segs[1].start == 2); + EXPECT(segs[1].end == 5); + reftable_free(segs); +} + +static void test_sizes_to_segments_empty(void) +{ + int seglen = 0; + struct segment *segs = sizes_to_segments(&seglen, NULL, 0); + EXPECT(seglen == 0); + reftable_free(segs); +} + +static void test_sizes_to_segments_all_equal(void) +{ + uint64_t sizes[] = { 5, 5 }; + + int seglen = 0; + struct segment *segs = + sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes)); + EXPECT(seglen == 1); + EXPECT(segs[0].start == 0); + EXPECT(segs[0].end == 2); + reftable_free(segs); +} + +static void test_suggest_compaction_segment(void) +{ + uint64_t sizes[] = { 128, 64, 17, 16, 9, 9, 9, 16, 16 }; + /* .................0 1 2 3 4 5 6 */ + struct segment min = + suggest_compaction_segment(sizes, ARRAY_SIZE(sizes)); + EXPECT(min.start == 2); + EXPECT(min.end == 7); +} + +static void test_suggest_compaction_segment_nothing(void) +{ + uint64_t sizes[] = { 64, 32, 16, 8, 4, 2 }; + struct segment result = + suggest_compaction_segment(sizes, ARRAY_SIZE(sizes)); + EXPECT(result.start == result.end); +} + +static void test_reflog_expire(void) +{ + char *dir = get_tmp_dir(__LINE__); + + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + struct reftable_log_record logs[20] = { { NULL } }; + int N = ARRAY_SIZE(logs) - 1; + int i = 0; + int err; + struct reftable_log_expiry_config expiry = { + .time = 10, + }; + struct reftable_log_record log = { NULL }; + + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + for (i = 1; i <= N; i++) { + char buf[256]; + snprintf(buf, sizeof(buf), "branch%02d", i); + + logs[i].refname = xstrdup(buf); + logs[i].update_index = i; + logs[i].value_type = REFTABLE_LOG_UPDATE; + logs[i].value.update.time = i; + logs[i].value.update.new_hash = reftable_malloc(GIT_SHA1_RAWSZ); + logs[i].value.update.email = xstrdup("identity@invalid"); + set_test_hash(logs[i].value.update.new_hash, i); + } + + for (i = 1; i <= N; i++) { + struct write_log_arg arg = { + .log = &logs[i], + .update_index = reftable_stack_next_update_index(st), + }; + int err = reftable_stack_add(st, &write_test_log, &arg); + EXPECT_ERR(err); + } + + err = reftable_stack_compact_all(st, NULL); + EXPECT_ERR(err); + + err = reftable_stack_compact_all(st, &expiry); + EXPECT_ERR(err); + + err = reftable_stack_read_log(st, logs[9].refname, &log); + EXPECT(err == 1); + + err = reftable_stack_read_log(st, logs[11].refname, &log); + EXPECT_ERR(err); + + expiry.min_update_index = 15; + err = reftable_stack_compact_all(st, &expiry); + EXPECT_ERR(err); + + err = reftable_stack_read_log(st, logs[14].refname, &log); + EXPECT(err == 1); + + err = reftable_stack_read_log(st, logs[16].refname, &log); + EXPECT_ERR(err); + + /* cleanup */ + reftable_stack_destroy(st); + for (i = 0; i <= N; i++) { + reftable_log_record_release(&logs[i]); + } + clear_dir(dir); + reftable_log_record_release(&log); +} + +static int write_nothing(struct reftable_writer *wr, void *arg) +{ + reftable_writer_set_limits(wr, 1, 1); + return 0; +} + +static void test_empty_add(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + char *dir = get_tmp_dir(__LINE__); + + struct reftable_stack *st2 = NULL; + + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_add(st, &write_nothing, NULL); + EXPECT_ERR(err); + + err = reftable_new_stack(&st2, dir, cfg); + EXPECT_ERR(err); + clear_dir(dir); + reftable_stack_destroy(st); + reftable_stack_destroy(st2); +} + +static void test_reftable_stack_auto_compaction(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + char *dir = get_tmp_dir(__LINE__); + + int err, i; + int N = 100; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + st->disable_auto_compact = 1; /* call manually below for coverage. */ + for (i = 0; i < N; i++) { + char name[100]; + struct reftable_ref_record ref = { + .refname = name, + .update_index = reftable_stack_next_update_index(st), + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + snprintf(name, sizeof(name), "branch%04d", i); + + err = reftable_stack_add(st, &write_test_ref, &ref); + EXPECT_ERR(err); + + err = reftable_stack_auto_compact(st); + EXPECT_ERR(err); + EXPECT(i < 3 || st->merged->stack_len < 2 * fastlog2(i)); + } + + EXPECT(reftable_stack_compaction_stats(st)->entries_written < + (uint64_t)(N * fastlog2(N))); + + reftable_stack_destroy(st); + clear_dir(dir); +} + +static void test_reftable_stack_compaction_concurrent(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st1 = NULL, *st2 = NULL; + char *dir = get_tmp_dir(__LINE__); + + int err, i; + int N = 3; + + err = reftable_new_stack(&st1, dir, cfg); + EXPECT_ERR(err); + + for (i = 0; i < N; i++) { + char name[100]; + struct reftable_ref_record ref = { + .refname = name, + .update_index = reftable_stack_next_update_index(st1), + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + snprintf(name, sizeof(name), "branch%04d", i); + + err = reftable_stack_add(st1, &write_test_ref, &ref); + EXPECT_ERR(err); + } + + err = reftable_new_stack(&st2, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_compact_all(st1, NULL); + EXPECT_ERR(err); + + reftable_stack_destroy(st1); + reftable_stack_destroy(st2); + + EXPECT(count_dir_entries(dir) == 2); + clear_dir(dir); +} + +static void unclean_stack_close(struct reftable_stack *st) +{ + /* break abstraction boundary to simulate unclean shutdown. */ + int i = 0; + for (; i < st->readers_len; i++) { + reftable_reader_free(st->readers[i]); + } + st->readers_len = 0; + FREE_AND_NULL(st->readers); +} + +static void test_reftable_stack_compaction_concurrent_clean(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st1 = NULL, *st2 = NULL, *st3 = NULL; + char *dir = get_tmp_dir(__LINE__); + + int err, i; + int N = 3; + + err = reftable_new_stack(&st1, dir, cfg); + EXPECT_ERR(err); + + for (i = 0; i < N; i++) { + char name[100]; + struct reftable_ref_record ref = { + .refname = name, + .update_index = reftable_stack_next_update_index(st1), + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + snprintf(name, sizeof(name), "branch%04d", i); + + err = reftable_stack_add(st1, &write_test_ref, &ref); + EXPECT_ERR(err); + } + + err = reftable_new_stack(&st2, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_compact_all(st1, NULL); + EXPECT_ERR(err); + + unclean_stack_close(st1); + unclean_stack_close(st2); + + err = reftable_new_stack(&st3, dir, cfg); + EXPECT_ERR(err); + + err = reftable_stack_clean(st3); + EXPECT_ERR(err); + EXPECT(count_dir_entries(dir) == 2); + + reftable_stack_destroy(st1); + reftable_stack_destroy(st2); + reftable_stack_destroy(st3); + + clear_dir(dir); +} + +int stack_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_empty_add); + RUN_TEST(test_log2); + RUN_TEST(test_names_equal); + RUN_TEST(test_parse_names); + RUN_TEST(test_read_file); + RUN_TEST(test_reflog_expire); + RUN_TEST(test_reftable_stack_add); + RUN_TEST(test_reftable_stack_add_one); + RUN_TEST(test_reftable_stack_auto_compaction); + RUN_TEST(test_reftable_stack_compaction_concurrent); + RUN_TEST(test_reftable_stack_compaction_concurrent_clean); + RUN_TEST(test_reftable_stack_hash_id); + RUN_TEST(test_reftable_stack_lock_failure); + RUN_TEST(test_reftable_stack_log_normalize); + RUN_TEST(test_reftable_stack_tombstone); + RUN_TEST(test_reftable_stack_transaction_api); + RUN_TEST(test_reftable_stack_update_index_check); + RUN_TEST(test_reftable_stack_uptodate); + RUN_TEST(test_reftable_stack_validate_refname); + RUN_TEST(test_sizes_to_segments); + RUN_TEST(test_sizes_to_segments_all_equal); + RUN_TEST(test_sizes_to_segments_empty); + RUN_TEST(test_suggest_compaction_segment); + RUN_TEST(test_suggest_compaction_segment_nothing); + return 0; +} diff --git a/reftable/system.h b/reftable/system.h new file mode 100644 index 0000000000..18f9207dfe --- /dev/null +++ b/reftable/system.h @@ -0,0 +1,21 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef SYSTEM_H +#define SYSTEM_H + +/* This header glues the reftable library to the rest of Git */ + +#include "git-compat-util.h" +#include "strbuf.h" +#include "hash.h" /* hash ID, sizes.*/ +#include "dir.h" /* remove_dir_recursively, for tests.*/ + +int hash_size(uint32_t id); + +#endif diff --git a/reftable/test_framework.c b/reftable/test_framework.c new file mode 100644 index 0000000000..84ac972cad --- /dev/null +++ b/reftable/test_framework.c @@ -0,0 +1,23 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" +#include "test_framework.h" + +#include "basics.h" + +void set_test_hash(uint8_t *p, int i) +{ + memset(p, (uint8_t)i, hash_size(GIT_SHA1_FORMAT_ID)); +} + +ssize_t strbuf_add_void(void *b, const void *data, size_t sz) +{ + strbuf_add(b, data, sz); + return sz; +} diff --git a/reftable/test_framework.h b/reftable/test_framework.h new file mode 100644 index 0000000000..774cb275bf --- /dev/null +++ b/reftable/test_framework.h @@ -0,0 +1,53 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef TEST_FRAMEWORK_H +#define TEST_FRAMEWORK_H + +#include "system.h" +#include "reftable-error.h" + +#define EXPECT_ERR(c) \ + if (c != 0) { \ + fflush(stderr); \ + fflush(stdout); \ + fprintf(stderr, "%s: %d: error == %d (%s), want 0\n", \ + __FILE__, __LINE__, c, reftable_error_str(c)); \ + abort(); \ + } + +#define EXPECT_STREQ(a, b) \ + if (strcmp(a, b)) { \ + fflush(stderr); \ + fflush(stdout); \ + fprintf(stderr, "%s:%d: %s (%s) != %s (%s)\n", __FILE__, \ + __LINE__, #a, a, #b, b); \ + abort(); \ + } + +#define EXPECT(c) \ + if (!(c)) { \ + fflush(stderr); \ + fflush(stdout); \ + fprintf(stderr, "%s: %d: failed assertion %s\n", __FILE__, \ + __LINE__, #c); \ + abort(); \ + } + +#define RUN_TEST(f) \ + fprintf(stderr, "running %s\n", #f); \ + fflush(stderr); \ + f(); + +void set_test_hash(uint8_t *p, int i); + +/* Like strbuf_add, but suitable for passing to reftable_new_writer + */ +ssize_t strbuf_add_void(void *b, const void *data, size_t sz); + +#endif diff --git a/reftable/tree.c b/reftable/tree.c new file mode 100644 index 0000000000..82db7995dd --- /dev/null +++ b/reftable/tree.c @@ -0,0 +1,63 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "tree.h" + +#include "basics.h" +#include "system.h" + +struct tree_node *tree_search(void *key, struct tree_node **rootp, + int (*compare)(const void *, const void *), + int insert) +{ + int res; + if (*rootp == NULL) { + if (!insert) { + return NULL; + } else { + struct tree_node *n = + reftable_calloc(sizeof(struct tree_node)); + n->key = key; + *rootp = n; + return *rootp; + } + } + + res = compare(key, (*rootp)->key); + if (res < 0) + return tree_search(key, &(*rootp)->left, compare, insert); + else if (res > 0) + return tree_search(key, &(*rootp)->right, compare, insert); + return *rootp; +} + +void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), + void *arg) +{ + if (t->left) { + infix_walk(t->left, action, arg); + } + action(arg, t->key); + if (t->right) { + infix_walk(t->right, action, arg); + } +} + +void tree_free(struct tree_node *t) +{ + if (t == NULL) { + return; + } + if (t->left) { + tree_free(t->left); + } + if (t->right) { + tree_free(t->right); + } + reftable_free(t); +} diff --git a/reftable/tree.h b/reftable/tree.h new file mode 100644 index 0000000000..fbdd002e23 --- /dev/null +++ b/reftable/tree.h @@ -0,0 +1,34 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef TREE_H +#define TREE_H + +/* tree_node is a generic binary search tree. */ +struct tree_node { + void *key; + struct tree_node *left, *right; +}; + +/* looks for `key` in `rootp` using `compare` as comparison function. If insert + * is set, insert the key if it's not found. Else, return NULL. + */ +struct tree_node *tree_search(void *key, struct tree_node **rootp, + int (*compare)(const void *, const void *), + int insert); + +/* performs an infix walk of the tree. */ +void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), + void *arg); + +/* + * deallocates the tree nodes recursively. Keys should be deallocated separately + * by walking over the tree. */ +void tree_free(struct tree_node *t); + +#endif diff --git a/reftable/tree_test.c b/reftable/tree_test.c new file mode 100644 index 0000000000..cbff125588 --- /dev/null +++ b/reftable/tree_test.c @@ -0,0 +1,61 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "tree.h" + +#include "basics.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static int test_compare(const void *a, const void *b) +{ + return (char *)a - (char *)b; +} + +struct curry { + void *last; +}; + +static void check_increasing(void *arg, void *key) +{ + struct curry *c = arg; + if (c->last) { + EXPECT(test_compare(c->last, key) < 0); + } + c->last = key; +} + +static void test_tree(void) +{ + struct tree_node *root = NULL; + + void *values[11] = { NULL }; + struct tree_node *nodes[11] = { NULL }; + int i = 1; + struct curry c = { NULL }; + do { + nodes[i] = tree_search(values + i, &root, &test_compare, 1); + i = (i * 7) % 11; + } while (i != 1); + + for (i = 1; i < ARRAY_SIZE(nodes); i++) { + EXPECT(values + i == nodes[i]->key); + EXPECT(nodes[i] == + tree_search(values + i, &root, &test_compare, 0)); + } + + infix_walk(root, check_increasing, &c); + tree_free(root); +} + +int tree_test_main(int argc, const char *argv[]) +{ + RUN_TEST(test_tree); + return 0; +} diff --git a/reftable/writer.c b/reftable/writer.c new file mode 100644 index 0000000000..427f1317c6 --- /dev/null +++ b/reftable/writer.c @@ -0,0 +1,707 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "writer.h" + +#include "system.h" + +#include "block.h" +#include "constants.h" +#include "record.h" +#include "tree.h" +#include "reftable-error.h" + +/* finishes a block, and writes it to storage */ +static int writer_flush_block(struct reftable_writer *w); + +/* deallocates memory related to the index */ +static void writer_clear_index(struct reftable_writer *w); + +/* finishes writing a 'r' (refs) or 'g' (reflogs) section */ +static int writer_finish_public_section(struct reftable_writer *w); + +static struct reftable_block_stats * +writer_reftable_block_stats(struct reftable_writer *w, uint8_t typ) +{ + switch (typ) { + case 'r': + return &w->stats.ref_stats; + case 'o': + return &w->stats.obj_stats; + case 'i': + return &w->stats.idx_stats; + case 'g': + return &w->stats.log_stats; + } + abort(); + return NULL; +} + +/* write data, queuing the padding for the next write. Returns negative for + * error. */ +static int padded_write(struct reftable_writer *w, uint8_t *data, size_t len, + int padding) +{ + int n = 0; + if (w->pending_padding > 0) { + uint8_t *zeroed = reftable_calloc(w->pending_padding); + int n = w->write(w->write_arg, zeroed, w->pending_padding); + if (n < 0) + return n; + + w->pending_padding = 0; + reftable_free(zeroed); + } + + w->pending_padding = padding; + n = w->write(w->write_arg, data, len); + if (n < 0) + return n; + n += padding; + return 0; +} + +static void options_set_defaults(struct reftable_write_options *opts) +{ + if (opts->restart_interval == 0) { + opts->restart_interval = 16; + } + + if (opts->hash_id == 0) { + opts->hash_id = GIT_SHA1_FORMAT_ID; + } + if (opts->block_size == 0) { + opts->block_size = DEFAULT_BLOCK_SIZE; + } +} + +static int writer_version(struct reftable_writer *w) +{ + return (w->opts.hash_id == 0 || w->opts.hash_id == GIT_SHA1_FORMAT_ID) ? + 1 : + 2; +} + +static int writer_write_header(struct reftable_writer *w, uint8_t *dest) +{ + memcpy(dest, "REFT", 4); + + dest[4] = writer_version(w); + + put_be24(dest + 5, w->opts.block_size); + put_be64(dest + 8, w->min_update_index); + put_be64(dest + 16, w->max_update_index); + if (writer_version(w) == 2) { + put_be32(dest + 24, w->opts.hash_id); + } + return header_size(writer_version(w)); +} + +static void writer_reinit_block_writer(struct reftable_writer *w, uint8_t typ) +{ + int block_start = 0; + if (w->next == 0) { + block_start = header_size(writer_version(w)); + } + + strbuf_release(&w->last_key); + block_writer_init(&w->block_writer_data, typ, w->block, + w->opts.block_size, block_start, + hash_size(w->opts.hash_id)); + w->block_writer = &w->block_writer_data; + w->block_writer->restart_interval = w->opts.restart_interval; +} + +static struct strbuf reftable_empty_strbuf = STRBUF_INIT; + +struct reftable_writer * +reftable_new_writer(ssize_t (*writer_func)(void *, const void *, size_t), + void *writer_arg, struct reftable_write_options *opts) +{ + struct reftable_writer *wp = + reftable_calloc(sizeof(struct reftable_writer)); + strbuf_init(&wp->block_writer_data.last_key, 0); + options_set_defaults(opts); + if (opts->block_size >= (1 << 24)) { + /* TODO - error return? */ + abort(); + } + wp->last_key = reftable_empty_strbuf; + wp->block = reftable_calloc(opts->block_size); + wp->write = writer_func; + wp->write_arg = writer_arg; + wp->opts = *opts; + writer_reinit_block_writer(wp, BLOCK_TYPE_REF); + + return wp; +} + +void reftable_writer_set_limits(struct reftable_writer *w, uint64_t min, + uint64_t max) +{ + w->min_update_index = min; + w->max_update_index = max; +} + +void reftable_writer_free(struct reftable_writer *w) +{ + if (!w) + return; + reftable_free(w->block); + reftable_free(w); +} + +struct obj_index_tree_node { + struct strbuf hash; + uint64_t *offsets; + size_t offset_len; + size_t offset_cap; +}; + +#define OBJ_INDEX_TREE_NODE_INIT \ + { \ + .hash = STRBUF_INIT \ + } + +static int obj_index_tree_node_compare(const void *a, const void *b) +{ + return strbuf_cmp(&((const struct obj_index_tree_node *)a)->hash, + &((const struct obj_index_tree_node *)b)->hash); +} + +static void writer_index_hash(struct reftable_writer *w, struct strbuf *hash) +{ + uint64_t off = w->next; + + struct obj_index_tree_node want = { .hash = *hash }; + + struct tree_node *node = tree_search(&want, &w->obj_index_tree, + &obj_index_tree_node_compare, 0); + struct obj_index_tree_node *key = NULL; + if (node == NULL) { + struct obj_index_tree_node empty = OBJ_INDEX_TREE_NODE_INIT; + key = reftable_malloc(sizeof(struct obj_index_tree_node)); + *key = empty; + + strbuf_reset(&key->hash); + strbuf_addbuf(&key->hash, hash); + tree_search((void *)key, &w->obj_index_tree, + &obj_index_tree_node_compare, 1); + } else { + key = node->key; + } + + if (key->offset_len > 0 && key->offsets[key->offset_len - 1] == off) { + return; + } + + if (key->offset_len == key->offset_cap) { + key->offset_cap = 2 * key->offset_cap + 1; + key->offsets = reftable_realloc( + key->offsets, sizeof(uint64_t) * key->offset_cap); + } + + key->offsets[key->offset_len++] = off; +} + +static int writer_add_record(struct reftable_writer *w, + struct reftable_record *rec) +{ + struct strbuf key = STRBUF_INIT; + int err = -1; + reftable_record_key(rec, &key); + if (strbuf_cmp(&w->last_key, &key) >= 0) { + err = REFTABLE_API_ERROR; + goto done; + } + + strbuf_reset(&w->last_key); + strbuf_addbuf(&w->last_key, &key); + if (w->block_writer == NULL) { + writer_reinit_block_writer(w, reftable_record_type(rec)); + } + + assert(block_writer_type(w->block_writer) == reftable_record_type(rec)); + + if (block_writer_add(w->block_writer, rec) == 0) { + err = 0; + goto done; + } + + err = writer_flush_block(w); + if (err < 0) { + goto done; + } + + writer_reinit_block_writer(w, reftable_record_type(rec)); + err = block_writer_add(w->block_writer, rec); + if (err == -1) { + /* we are writing into memory, so an error can only mean it + * doesn't fit. */ + err = REFTABLE_ENTRY_TOO_BIG_ERROR; + goto done; + } + +done: + strbuf_release(&key); + return err; +} + +int reftable_writer_add_ref(struct reftable_writer *w, + struct reftable_ref_record *ref) +{ + struct reftable_record rec = { + .type = BLOCK_TYPE_REF, + .u = { + .ref = *ref + }, + }; + int err = 0; + + if (ref->refname == NULL) + return REFTABLE_API_ERROR; + if (ref->update_index < w->min_update_index || + ref->update_index > w->max_update_index) + return REFTABLE_API_ERROR; + + rec.u.ref.update_index -= w->min_update_index; + + err = writer_add_record(w, &rec); + if (err < 0) + return err; + + if (!w->opts.skip_index_objects && reftable_ref_record_val1(ref)) { + struct strbuf h = STRBUF_INIT; + strbuf_add(&h, (char *)reftable_ref_record_val1(ref), + hash_size(w->opts.hash_id)); + writer_index_hash(w, &h); + strbuf_release(&h); + } + + if (!w->opts.skip_index_objects && reftable_ref_record_val2(ref)) { + struct strbuf h = STRBUF_INIT; + strbuf_add(&h, reftable_ref_record_val2(ref), + hash_size(w->opts.hash_id)); + writer_index_hash(w, &h); + strbuf_release(&h); + } + return 0; +} + +int reftable_writer_add_refs(struct reftable_writer *w, + struct reftable_ref_record *refs, int n) +{ + int err = 0; + int i = 0; + QSORT(refs, n, reftable_ref_record_compare_name); + for (i = 0; err == 0 && i < n; i++) { + err = reftable_writer_add_ref(w, &refs[i]); + } + return err; +} + +static int reftable_writer_add_log_verbatim(struct reftable_writer *w, + struct reftable_log_record *log) +{ + struct reftable_record rec = { + .type = BLOCK_TYPE_LOG, + .u = { + .log = *log, + }, + }; + if (w->block_writer && + block_writer_type(w->block_writer) == BLOCK_TYPE_REF) { + int err = writer_finish_public_section(w); + if (err < 0) + return err; + } + + w->next -= w->pending_padding; + w->pending_padding = 0; + return writer_add_record(w, &rec); +} + +int reftable_writer_add_log(struct reftable_writer *w, + struct reftable_log_record *log) +{ + char *input_log_message = NULL; + struct strbuf cleaned_message = STRBUF_INIT; + int err = 0; + + if (log->value_type == REFTABLE_LOG_DELETION) + return reftable_writer_add_log_verbatim(w, log); + + if (log->refname == NULL) + return REFTABLE_API_ERROR; + + input_log_message = log->value.update.message; + if (!w->opts.exact_log_message && log->value.update.message) { + strbuf_addstr(&cleaned_message, log->value.update.message); + while (cleaned_message.len && + cleaned_message.buf[cleaned_message.len - 1] == '\n') + strbuf_setlen(&cleaned_message, + cleaned_message.len - 1); + if (strchr(cleaned_message.buf, '\n')) { + /* multiple lines not allowed. */ + err = REFTABLE_API_ERROR; + goto done; + } + strbuf_addstr(&cleaned_message, "\n"); + log->value.update.message = cleaned_message.buf; + } + + err = reftable_writer_add_log_verbatim(w, log); + log->value.update.message = input_log_message; +done: + strbuf_release(&cleaned_message); + return err; +} + +int reftable_writer_add_logs(struct reftable_writer *w, + struct reftable_log_record *logs, int n) +{ + int err = 0; + int i = 0; + QSORT(logs, n, reftable_log_record_compare_key); + + for (i = 0; err == 0 && i < n; i++) { + err = reftable_writer_add_log(w, &logs[i]); + } + return err; +} + +static int writer_finish_section(struct reftable_writer *w) +{ + uint8_t typ = block_writer_type(w->block_writer); + uint64_t index_start = 0; + int max_level = 0; + int threshold = w->opts.unpadded ? 1 : 3; + int before_blocks = w->stats.idx_stats.blocks; + int err = writer_flush_block(w); + int i = 0; + struct reftable_block_stats *bstats = NULL; + if (err < 0) + return err; + + while (w->index_len > threshold) { + struct reftable_index_record *idx = NULL; + int idx_len = 0; + + max_level++; + index_start = w->next; + writer_reinit_block_writer(w, BLOCK_TYPE_INDEX); + + idx = w->index; + idx_len = w->index_len; + + w->index = NULL; + w->index_len = 0; + w->index_cap = 0; + for (i = 0; i < idx_len; i++) { + struct reftable_record rec = { + .type = BLOCK_TYPE_INDEX, + .u = { + .idx = idx[i], + }, + }; + if (block_writer_add(w->block_writer, &rec) == 0) { + continue; + } + + err = writer_flush_block(w); + if (err < 0) + return err; + + writer_reinit_block_writer(w, BLOCK_TYPE_INDEX); + + err = block_writer_add(w->block_writer, &rec); + if (err != 0) { + /* write into fresh block should always succeed + */ + abort(); + } + } + for (i = 0; i < idx_len; i++) { + strbuf_release(&idx[i].last_key); + } + reftable_free(idx); + } + + writer_clear_index(w); + + err = writer_flush_block(w); + if (err < 0) + return err; + + bstats = writer_reftable_block_stats(w, typ); + bstats->index_blocks = w->stats.idx_stats.blocks - before_blocks; + bstats->index_offset = index_start; + bstats->max_index_level = max_level; + + /* Reinit lastKey, as the next section can start with any key. */ + w->last_key.len = 0; + + return 0; +} + +struct common_prefix_arg { + struct strbuf *last; + int max; +}; + +static void update_common(void *void_arg, void *key) +{ + struct common_prefix_arg *arg = void_arg; + struct obj_index_tree_node *entry = key; + if (arg->last) { + int n = common_prefix_size(&entry->hash, arg->last); + if (n > arg->max) { + arg->max = n; + } + } + arg->last = &entry->hash; +} + +struct write_record_arg { + struct reftable_writer *w; + int err; +}; + +static void write_object_record(void *void_arg, void *key) +{ + struct write_record_arg *arg = void_arg; + struct obj_index_tree_node *entry = key; + struct reftable_record + rec = { .type = BLOCK_TYPE_OBJ, + .u.obj = { + .hash_prefix = (uint8_t *)entry->hash.buf, + .hash_prefix_len = arg->w->stats.object_id_len, + .offsets = entry->offsets, + .offset_len = entry->offset_len, + } }; + if (arg->err < 0) + goto done; + + arg->err = block_writer_add(arg->w->block_writer, &rec); + if (arg->err == 0) + goto done; + + arg->err = writer_flush_block(arg->w); + if (arg->err < 0) + goto done; + + writer_reinit_block_writer(arg->w, BLOCK_TYPE_OBJ); + arg->err = block_writer_add(arg->w->block_writer, &rec); + if (arg->err == 0) + goto done; + + rec.u.obj.offset_len = 0; + arg->err = block_writer_add(arg->w->block_writer, &rec); + + /* Should be able to write into a fresh block. */ + assert(arg->err == 0); + +done:; +} + +static void object_record_free(void *void_arg, void *key) +{ + struct obj_index_tree_node *entry = key; + + FREE_AND_NULL(entry->offsets); + strbuf_release(&entry->hash); + reftable_free(entry); +} + +static int writer_dump_object_index(struct reftable_writer *w) +{ + struct write_record_arg closure = { .w = w }; + struct common_prefix_arg common = { + .max = 1, /* obj_id_len should be >= 2. */ + }; + if (w->obj_index_tree) { + infix_walk(w->obj_index_tree, &update_common, &common); + } + w->stats.object_id_len = common.max + 1; + + writer_reinit_block_writer(w, BLOCK_TYPE_OBJ); + + if (w->obj_index_tree) { + infix_walk(w->obj_index_tree, &write_object_record, &closure); + } + + if (closure.err < 0) + return closure.err; + return writer_finish_section(w); +} + +static int writer_finish_public_section(struct reftable_writer *w) +{ + uint8_t typ = 0; + int err = 0; + + if (w->block_writer == NULL) + return 0; + + typ = block_writer_type(w->block_writer); + err = writer_finish_section(w); + if (err < 0) + return err; + if (typ == BLOCK_TYPE_REF && !w->opts.skip_index_objects && + w->stats.ref_stats.index_blocks > 0) { + err = writer_dump_object_index(w); + if (err < 0) + return err; + } + + if (w->obj_index_tree) { + infix_walk(w->obj_index_tree, &object_record_free, NULL); + tree_free(w->obj_index_tree); + w->obj_index_tree = NULL; + } + + w->block_writer = NULL; + return 0; +} + +int reftable_writer_close(struct reftable_writer *w) +{ + uint8_t footer[72]; + uint8_t *p = footer; + int err = writer_finish_public_section(w); + int empty_table = w->next == 0; + if (err != 0) + goto done; + w->pending_padding = 0; + if (empty_table) { + /* Empty tables need a header anyway. */ + uint8_t header[28]; + int n = writer_write_header(w, header); + err = padded_write(w, header, n, 0); + if (err < 0) + goto done; + } + + p += writer_write_header(w, footer); + put_be64(p, w->stats.ref_stats.index_offset); + p += 8; + put_be64(p, (w->stats.obj_stats.offset) << 5 | w->stats.object_id_len); + p += 8; + put_be64(p, w->stats.obj_stats.index_offset); + p += 8; + + put_be64(p, w->stats.log_stats.offset); + p += 8; + put_be64(p, w->stats.log_stats.index_offset); + p += 8; + + put_be32(p, crc32(0, footer, p - footer)); + p += 4; + + err = padded_write(w, footer, footer_size(writer_version(w)), 0); + if (err < 0) + goto done; + + if (empty_table) { + err = REFTABLE_EMPTY_TABLE_ERROR; + goto done; + } + +done: + /* free up memory. */ + block_writer_release(&w->block_writer_data); + writer_clear_index(w); + strbuf_release(&w->last_key); + return err; +} + +static void writer_clear_index(struct reftable_writer *w) +{ + int i = 0; + for (i = 0; i < w->index_len; i++) { + strbuf_release(&w->index[i].last_key); + } + + FREE_AND_NULL(w->index); + w->index_len = 0; + w->index_cap = 0; +} + +static const int debug = 0; + +static int writer_flush_nonempty_block(struct reftable_writer *w) +{ + uint8_t typ = block_writer_type(w->block_writer); + struct reftable_block_stats *bstats = + writer_reftable_block_stats(w, typ); + uint64_t block_typ_off = (bstats->blocks == 0) ? w->next : 0; + int raw_bytes = block_writer_finish(w->block_writer); + int padding = 0; + int err = 0; + struct reftable_index_record ir = { .last_key = STRBUF_INIT }; + if (raw_bytes < 0) + return raw_bytes; + + if (!w->opts.unpadded && typ != BLOCK_TYPE_LOG) { + padding = w->opts.block_size - raw_bytes; + } + + if (block_typ_off > 0) { + bstats->offset = block_typ_off; + } + + bstats->entries += w->block_writer->entries; + bstats->restarts += w->block_writer->restart_len; + bstats->blocks++; + w->stats.blocks++; + + if (debug) { + fprintf(stderr, "block %c off %" PRIu64 " sz %d (%d)\n", typ, + w->next, raw_bytes, + get_be24(w->block + w->block_writer->header_off + 1)); + } + + if (w->next == 0) { + writer_write_header(w, w->block); + } + + err = padded_write(w, w->block, raw_bytes, padding); + if (err < 0) + return err; + + if (w->index_cap == w->index_len) { + w->index_cap = 2 * w->index_cap + 1; + w->index = reftable_realloc( + w->index, + sizeof(struct reftable_index_record) * w->index_cap); + } + + ir.offset = w->next; + strbuf_reset(&ir.last_key); + strbuf_addbuf(&ir.last_key, &w->block_writer->last_key); + w->index[w->index_len] = ir; + + w->index_len++; + w->next += padding + raw_bytes; + w->block_writer = NULL; + return 0; +} + +static int writer_flush_block(struct reftable_writer *w) +{ + if (w->block_writer == NULL) + return 0; + if (w->block_writer->entries == 0) + return 0; + return writer_flush_nonempty_block(w); +} + +const struct reftable_stats *reftable_writer_stats(struct reftable_writer *w) +{ + return &w->stats; +} diff --git a/reftable/writer.h b/reftable/writer.h new file mode 100644 index 0000000000..09b88673d9 --- /dev/null +++ b/reftable/writer.h @@ -0,0 +1,50 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef WRITER_H +#define WRITER_H + +#include "basics.h" +#include "block.h" +#include "tree.h" +#include "reftable-writer.h" + +struct reftable_writer { + ssize_t (*write)(void *, const void *, size_t); + void *write_arg; + int pending_padding; + struct strbuf last_key; + + /* offset of next block to write. */ + uint64_t next; + uint64_t min_update_index, max_update_index; + struct reftable_write_options opts; + + /* memory buffer for writing */ + uint8_t *block; + + /* writer for the current section. NULL or points to + * block_writer_data */ + struct block_writer *block_writer; + + struct block_writer block_writer_data; + + /* pending index records for the current section */ + struct reftable_index_record *index; + size_t index_len; + size_t index_cap; + + /* + * tree for use with tsearch; used to populate the 'o' inverse OID + * map */ + struct tree_node *obj_index_tree; + + struct reftable_stats stats; +}; + +#endif |