diff options
Diffstat (limited to 'builtin/index-pack.c')
| -rw-r--r-- | builtin/index-pack.c | 1634 |
1 files changed, 1634 insertions, 0 deletions
diff --git a/builtin/index-pack.c b/builtin/index-pack.c new file mode 100644 index 0000000000..43d364b8d5 --- /dev/null +++ b/builtin/index-pack.c @@ -0,0 +1,1634 @@ +#include "builtin.h" +#include "delta.h" +#include "pack.h" +#include "csum-file.h" +#include "blob.h" +#include "commit.h" +#include "tag.h" +#include "tree.h" +#include "progress.h" +#include "fsck.h" +#include "exec_cmd.h" +#include "streaming.h" +#include "thread-utils.h" + +static const char index_pack_usage[] = +"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])"; + +struct object_entry { + struct pack_idx_entry idx; + unsigned long size; + unsigned int hdr_size; + enum object_type type; + enum object_type real_type; + unsigned delta_depth; + int base_object_no; +}; + +union delta_base { + unsigned char sha1[20]; + off_t offset; +}; + +struct base_data { + struct base_data *base; + struct base_data *child; + struct object_entry *obj; + void *data; + unsigned long size; + int ref_first, ref_last; + int ofs_first, ofs_last; +}; + +#if !defined(NO_PTHREADS) && defined(NO_THREAD_SAFE_PREAD) +/* pread() emulation is not thread-safe. Disable threading. */ +#define NO_PTHREADS +#endif + +struct thread_local { +#ifndef NO_PTHREADS + pthread_t thread; +#endif + struct base_data *base_cache; + size_t base_cache_used; +}; + +/* + * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want + * to memcmp() only the first 20 bytes. + */ +#define UNION_BASE_SZ 20 + +#define FLAG_LINK (1u<<20) +#define FLAG_CHECKED (1u<<21) + +struct delta_entry { + union delta_base base; + int obj_no; +}; + +static struct object_entry *objects; +static struct delta_entry *deltas; +static struct thread_local nothread_data; +static int nr_objects; +static int nr_deltas; +static int nr_resolved_deltas; +static int nr_threads; + +static int from_stdin; +static int strict; +static int verbose; + +static struct progress *progress; + +/* We always read in 4kB chunks. */ +static unsigned char input_buffer[4096]; +static unsigned int input_offset, input_len; +static off_t consumed_bytes; +static unsigned deepest_delta; +static git_SHA_CTX input_ctx; +static uint32_t input_crc32; +static int input_fd, output_fd, pack_fd; + +#ifndef NO_PTHREADS + +static struct thread_local *thread_data; +static int nr_dispatched; +static int threads_active; + +static pthread_mutex_t read_mutex; +#define read_lock() lock_mutex(&read_mutex) +#define read_unlock() unlock_mutex(&read_mutex) + +static pthread_mutex_t counter_mutex; +#define counter_lock() lock_mutex(&counter_mutex) +#define counter_unlock() unlock_mutex(&counter_mutex) + +static pthread_mutex_t work_mutex; +#define work_lock() lock_mutex(&work_mutex) +#define work_unlock() unlock_mutex(&work_mutex) + +static pthread_key_t key; + +static inline void lock_mutex(pthread_mutex_t *mutex) +{ + if (threads_active) + pthread_mutex_lock(mutex); +} + +static inline void unlock_mutex(pthread_mutex_t *mutex) +{ + if (threads_active) + pthread_mutex_unlock(mutex); +} + +/* + * Mutex and conditional variable can't be statically-initialized on Windows. + */ +static void init_thread(void) +{ + init_recursive_mutex(&read_mutex); + pthread_mutex_init(&counter_mutex, NULL); + pthread_mutex_init(&work_mutex, NULL); + pthread_key_create(&key, NULL); + thread_data = xcalloc(nr_threads, sizeof(*thread_data)); + threads_active = 1; +} + +static void cleanup_thread(void) +{ + if (!threads_active) + return; + threads_active = 0; + pthread_mutex_destroy(&read_mutex); + pthread_mutex_destroy(&counter_mutex); + pthread_mutex_destroy(&work_mutex); + pthread_key_delete(key); + free(thread_data); +} + +#else + +#define read_lock() +#define read_unlock() + +#define counter_lock() +#define counter_unlock() + +#define work_lock() +#define work_unlock() + +#endif + + +static int mark_link(struct object *obj, int type, void *data) +{ + if (!obj) + return -1; + + if (type != OBJ_ANY && obj->type != type) + die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1)); + + obj->flags |= FLAG_LINK; + return 0; +} + +/* The content of each linked object must have been checked + or it must be already present in the object database */ +static void check_object(struct object *obj) +{ + if (!obj) + return; + + if (!(obj->flags & FLAG_LINK)) + return; + + if (!(obj->flags & FLAG_CHECKED)) { + unsigned long size; + int type = sha1_object_info(obj->sha1, &size); + if (type != obj->type || type <= 0) + die(_("object of unexpected type")); + obj->flags |= FLAG_CHECKED; + return; + } +} + +static void check_objects(void) +{ + unsigned i, max; + + max = get_max_object_index(); + for (i = 0; i < max; i++) + check_object(get_indexed_object(i)); +} + + +/* Discard current buffer used content. */ +static void flush(void) +{ + if (input_offset) { + if (output_fd >= 0) + write_or_die(output_fd, input_buffer, input_offset); + git_SHA1_Update(&input_ctx, input_buffer, input_offset); + memmove(input_buffer, input_buffer + input_offset, input_len); + input_offset = 0; + } +} + +/* + * Make sure at least "min" bytes are available in the buffer, and + * return the pointer to the buffer. + */ +static void *fill(int min) +{ + if (min <= input_len) + return input_buffer + input_offset; + if (min > sizeof(input_buffer)) + die(Q_("cannot fill %d byte", + "cannot fill %d bytes", + min), + min); + flush(); + do { + ssize_t ret = xread(input_fd, input_buffer + input_len, + sizeof(input_buffer) - input_len); + if (ret <= 0) { + if (!ret) + die(_("early EOF")); + die_errno(_("read error on input")); + } + input_len += ret; + if (from_stdin) + display_throughput(progress, consumed_bytes + input_len); + } while (input_len < min); + return input_buffer; +} + +static void use(int bytes) +{ + if (bytes > input_len) + die(_("used more bytes than were available")); + input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes); + input_len -= bytes; + input_offset += bytes; + + /* make sure off_t is sufficiently large not to wrap */ + if (signed_add_overflows(consumed_bytes, bytes)) + die(_("pack too large for current definition of off_t")); + consumed_bytes += bytes; +} + +static const char *open_pack_file(const char *pack_name) +{ + if (from_stdin) { + input_fd = 0; + if (!pack_name) { + static char tmp_file[PATH_MAX]; + output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file), + "pack/tmp_pack_XXXXXX"); + pack_name = xstrdup(tmp_file); + } else + output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600); + if (output_fd < 0) + die_errno(_("unable to create '%s'"), pack_name); + pack_fd = output_fd; + } else { + input_fd = open(pack_name, O_RDONLY); + if (input_fd < 0) + die_errno(_("cannot open packfile '%s'"), pack_name); + output_fd = -1; + pack_fd = input_fd; + } + git_SHA1_Init(&input_ctx); + return pack_name; +} + +static void parse_pack_header(void) +{ + struct pack_header *hdr = fill(sizeof(struct pack_header)); + + /* Header consistency check */ + if (hdr->hdr_signature != htonl(PACK_SIGNATURE)) + die(_("pack signature mismatch")); + if (!pack_version_ok(hdr->hdr_version)) + die(_("pack version %"PRIu32" unsupported"), + ntohl(hdr->hdr_version)); + + nr_objects = ntohl(hdr->hdr_entries); + use(sizeof(struct pack_header)); +} + +static NORETURN void bad_object(unsigned long offset, const char *format, + ...) __attribute__((format (printf, 2, 3))); + +static NORETURN void bad_object(unsigned long offset, const char *format, ...) +{ + va_list params; + char buf[1024]; + + va_start(params, format); + vsnprintf(buf, sizeof(buf), format, params); + va_end(params); + die(_("pack has bad object at offset %lu: %s"), offset, buf); +} + +static inline struct thread_local *get_thread_data(void) +{ +#ifndef NO_PTHREADS + if (threads_active) + return pthread_getspecific(key); + assert(!threads_active && + "This should only be reached when all threads are gone"); +#endif + return ¬hread_data; +} + +#ifndef NO_PTHREADS +static void set_thread_data(struct thread_local *data) +{ + if (threads_active) + pthread_setspecific(key, data); +} +#endif + +static struct base_data *alloc_base_data(void) +{ + struct base_data *base = xmalloc(sizeof(struct base_data)); + memset(base, 0, sizeof(*base)); + base->ref_last = -1; + base->ofs_last = -1; + return base; +} + +static void free_base_data(struct base_data *c) +{ + if (c->data) { + free(c->data); + c->data = NULL; + get_thread_data()->base_cache_used -= c->size; + } +} + +static void prune_base_data(struct base_data *retain) +{ + struct base_data *b; + struct thread_local *data = get_thread_data(); + for (b = data->base_cache; + data->base_cache_used > delta_base_cache_limit && b; + b = b->child) { + if (b->data && b != retain) + free_base_data(b); + } +} + +static void link_base_data(struct base_data *base, struct base_data *c) +{ + if (base) + base->child = c; + else + get_thread_data()->base_cache = c; + + c->base = base; + c->child = NULL; + if (c->data) + get_thread_data()->base_cache_used += c->size; + prune_base_data(c); +} + +static void unlink_base_data(struct base_data *c) +{ + struct base_data *base = c->base; + if (base) + base->child = NULL; + else + get_thread_data()->base_cache = NULL; + free_base_data(c); +} + +static int is_delta_type(enum object_type type) +{ + return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA); +} + +static void *unpack_entry_data(unsigned long offset, unsigned long size, + enum object_type type, unsigned char *sha1) +{ + static char fixed_buf[8192]; + int status; + git_zstream stream; + void *buf; + git_SHA_CTX c; + char hdr[32]; + int hdrlen; + + if (!is_delta_type(type)) { + hdrlen = sprintf(hdr, "%s %lu", typename(type), size) + 1; + git_SHA1_Init(&c); + git_SHA1_Update(&c, hdr, hdrlen); + } else + sha1 = NULL; + if (type == OBJ_BLOB && size > big_file_threshold) + buf = fixed_buf; + else + buf = xmalloc(size); + + memset(&stream, 0, sizeof(stream)); + git_inflate_init(&stream); + stream.next_out = buf; + stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size; + + do { + unsigned char *last_out = stream.next_out; + stream.next_in = fill(1); + stream.avail_in = input_len; + status = git_inflate(&stream, 0); + use(input_len - stream.avail_in); + if (sha1) + git_SHA1_Update(&c, last_out, stream.next_out - last_out); + if (buf == fixed_buf) { + stream.next_out = buf; + stream.avail_out = sizeof(fixed_buf); + } + } while (status == Z_OK); + if (stream.total_out != size || status != Z_STREAM_END) + bad_object(offset, _("inflate returned %d"), status); + git_inflate_end(&stream); + if (sha1) + git_SHA1_Final(sha1, &c); + return buf == fixed_buf ? NULL : buf; +} + +static void *unpack_raw_entry(struct object_entry *obj, + union delta_base *delta_base, + unsigned char *sha1) +{ + unsigned char *p; + unsigned long size, c; + off_t base_offset; + unsigned shift; + void *data; + + obj->idx.offset = consumed_bytes; + input_crc32 = crc32(0, NULL, 0); + + p = fill(1); + c = *p; + use(1); + obj->type = (c >> 4) & 7; + size = (c & 15); + shift = 4; + while (c & 0x80) { + p = fill(1); + c = *p; + use(1); + size += (c & 0x7f) << shift; + shift += 7; + } + obj->size = size; + + switch (obj->type) { + case OBJ_REF_DELTA: + hashcpy(delta_base->sha1, fill(20)); + use(20); + break; + case OBJ_OFS_DELTA: + memset(delta_base, 0, sizeof(*delta_base)); + p = fill(1); + c = *p; + use(1); + base_offset = c & 127; + while (c & 128) { + base_offset += 1; + if (!base_offset || MSB(base_offset, 7)) + bad_object(obj->idx.offset, _("offset value overflow for delta base object")); + p = fill(1); + c = *p; + use(1); + base_offset = (base_offset << 7) + (c & 127); + } + delta_base->offset = obj->idx.offset - base_offset; + if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset) + bad_object(obj->idx.offset, _("delta base offset is out of bound")); + break; + case OBJ_COMMIT: + case OBJ_TREE: + case OBJ_BLOB: + case OBJ_TAG: + break; + default: + bad_object(obj->idx.offset, _("unknown object type %d"), obj->type); + } + obj->hdr_size = consumed_bytes - obj->idx.offset; + + data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1); + obj->idx.crc32 = input_crc32; + return data; +} + +static void *unpack_data(struct object_entry *obj, + int (*consume)(const unsigned char *, unsigned long, void *), + void *cb_data) +{ + off_t from = obj[0].idx.offset + obj[0].hdr_size; + unsigned long len = obj[1].idx.offset - from; + unsigned char *data, *inbuf; + git_zstream stream; + int status; + + data = xmalloc(consume ? 64*1024 : obj->size); + inbuf = xmalloc((len < 64*1024) ? len : 64*1024); + + memset(&stream, 0, sizeof(stream)); + git_inflate_init(&stream); + stream.next_out = data; + stream.avail_out = consume ? 64*1024 : obj->size; + + do { + ssize_t n = (len < 64*1024) ? len : 64*1024; + n = pread(pack_fd, inbuf, n, from); + if (n < 0) + die_errno(_("cannot pread pack file")); + if (!n) + die(Q_("premature end of pack file, %lu byte missing", + "premature end of pack file, %lu bytes missing", + len), + len); + from += n; + len -= n; + stream.next_in = inbuf; + stream.avail_in = n; + if (!consume) + status = git_inflate(&stream, 0); + else { + do { + status = git_inflate(&stream, 0); + if (consume(data, stream.next_out - data, cb_data)) { + free(inbuf); + free(data); + return NULL; + } + stream.next_out = data; + stream.avail_out = 64*1024; + } while (status == Z_OK && stream.avail_in); + } + } while (len && status == Z_OK && !stream.avail_in); + + /* This has been inflated OK when first encountered, so... */ + if (status != Z_STREAM_END || stream.total_out != obj->size) + die(_("serious inflate inconsistency")); + + git_inflate_end(&stream); + free(inbuf); + if (consume) { + free(data); + data = NULL; + } + return data; +} + +static void *get_data_from_pack(struct object_entry *obj) +{ + return unpack_data(obj, NULL, NULL); +} + +static int compare_delta_bases(const union delta_base *base1, + const union delta_base *base2, + enum object_type type1, + enum object_type type2) +{ + int cmp = type1 - type2; + if (cmp) + return cmp; + return memcmp(base1, base2, UNION_BASE_SZ); +} + +static int find_delta(const union delta_base *base, enum object_type type) +{ + int first = 0, last = nr_deltas; + + while (first < last) { + int next = (first + last) / 2; + struct delta_entry *delta = &deltas[next]; + int cmp; + + cmp = compare_delta_bases(base, &delta->base, + type, objects[delta->obj_no].type); + if (!cmp) + return next; + if (cmp < 0) { + last = next; + continue; + } + first = next+1; + } + return -first-1; +} + +static void find_delta_children(const union delta_base *base, + int *first_index, int *last_index, + enum object_type type) +{ + int first = find_delta(base, type); + int last = first; + int end = nr_deltas - 1; + + if (first < 0) { + *first_index = 0; + *last_index = -1; + return; + } + while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ)) + --first; + while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ)) + ++last; + *first_index = first; + *last_index = last; +} + +struct compare_data { + struct object_entry *entry; + struct git_istream *st; + unsigned char *buf; + unsigned long buf_size; +}; + +static int compare_objects(const unsigned char *buf, unsigned long size, + void *cb_data) +{ + struct compare_data *data = cb_data; + + if (data->buf_size < size) { + free(data->buf); + data->buf = xmalloc(size); + data->buf_size = size; + } + + while (size) { + ssize_t len = read_istream(data->st, data->buf, size); + if (len == 0) + die(_("SHA1 COLLISION FOUND WITH %s !"), + sha1_to_hex(data->entry->idx.sha1)); + if (len < 0) + die(_("unable to read %s"), + sha1_to_hex(data->entry->idx.sha1)); + if (memcmp(buf, data->buf, len)) + die(_("SHA1 COLLISION FOUND WITH %s !"), + sha1_to_hex(data->entry->idx.sha1)); + size -= len; + buf += len; + } + return 0; +} + +static int check_collison(struct object_entry *entry) +{ + struct compare_data data; + enum object_type type; + unsigned long size; + + if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB) + return -1; + + memset(&data, 0, sizeof(data)); + data.entry = entry; + data.st = open_istream(entry->idx.sha1, &type, &size, NULL); + if (!data.st) + return -1; + if (size != entry->size || type != entry->type) + die(_("SHA1 COLLISION FOUND WITH %s !"), + sha1_to_hex(entry->idx.sha1)); + unpack_data(entry, compare_objects, &data); + close_istream(data.st); + free(data.buf); + return 0; +} + +static void sha1_object(const void *data, struct object_entry *obj_entry, + unsigned long size, enum object_type type, + const unsigned char *sha1) +{ + void *new_data = NULL; + int collision_test_needed; + + assert(data || obj_entry); + + read_lock(); + collision_test_needed = has_sha1_file(sha1); + read_unlock(); + + if (collision_test_needed && !data) { + read_lock(); + if (!check_collison(obj_entry)) + collision_test_needed = 0; + read_unlock(); + } + if (collision_test_needed) { + void *has_data; + enum object_type has_type; + unsigned long has_size; + read_lock(); + has_type = sha1_object_info(sha1, &has_size); + if (has_type != type || has_size != size) + die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1)); + has_data = read_sha1_file(sha1, &has_type, &has_size); + read_unlock(); + if (!data) + data = new_data = get_data_from_pack(obj_entry); + if (!has_data) + die(_("cannot read existing object %s"), sha1_to_hex(sha1)); + if (size != has_size || type != has_type || + memcmp(data, has_data, size) != 0) + die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1)); + free(has_data); + } + + if (strict) { + read_lock(); + if (type == OBJ_BLOB) { + struct blob *blob = lookup_blob(sha1); + if (blob) + blob->object.flags |= FLAG_CHECKED; + else + die(_("invalid blob object %s"), sha1_to_hex(sha1)); + } else { + struct object *obj; + int eaten; + void *buf = (void *) data; + + if (!buf) + buf = new_data = get_data_from_pack(obj_entry); + + /* + * we do not need to free the memory here, as the + * buf is deleted by the caller. + */ + obj = parse_object_buffer(sha1, type, size, buf, &eaten); + if (!obj) + die(_("invalid %s"), typename(type)); + if (fsck_object(obj, 1, fsck_error_function)) + die(_("Error in object")); + if (fsck_walk(obj, mark_link, NULL)) + die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1)); + + if (obj->type == OBJ_TREE) { + struct tree *item = (struct tree *) obj; + item->buffer = NULL; + } + if (obj->type == OBJ_COMMIT) { + struct commit *commit = (struct commit *) obj; + commit->buffer = NULL; + } + obj->flags |= FLAG_CHECKED; + } + read_unlock(); + } + + free(new_data); +} + +/* + * This function is part of find_unresolved_deltas(). There are two + * walkers going in the opposite ways. + * + * The first one in find_unresolved_deltas() traverses down from + * parent node to children, deflating nodes along the way. However, + * memory for deflated nodes is limited by delta_base_cache_limit, so + * at some point parent node's deflated content may be freed. + * + * The second walker is this function, which goes from current node up + * to top parent if necessary to deflate the node. In normal + * situation, its parent node would be already deflated, so it just + * needs to apply delta. + * + * In the worst case scenario, parent node is no longer deflated because + * we're running out of delta_base_cache_limit; we need to re-deflate + * parents, possibly up to the top base. + * + * All deflated objects here are subject to be freed if we exceed + * delta_base_cache_limit, just like in find_unresolved_deltas(), we + * just need to make sure the last node is not freed. + */ +static void *get_base_data(struct base_data *c) +{ + if (!c->data) { + struct object_entry *obj = c->obj; + struct base_data **delta = NULL; + int delta_nr = 0, delta_alloc = 0; + + while (is_delta_type(c->obj->type) && !c->data) { + ALLOC_GROW(delta, delta_nr + 1, delta_alloc); + delta[delta_nr++] = c; + c = c->base; + } + if (!delta_nr) { + c->data = get_data_from_pack(obj); + c->size = obj->size; + get_thread_data()->base_cache_used += c->size; + prune_base_data(c); + } + for (; delta_nr > 0; delta_nr--) { + void *base, *raw; + c = delta[delta_nr - 1]; + obj = c->obj; + base = get_base_data(c->base); + raw = get_data_from_pack(obj); + c->data = patch_delta( + base, c->base->size, + raw, obj->size, + &c->size); + free(raw); + if (!c->data) + bad_object(obj->idx.offset, _("failed to apply delta")); + get_thread_data()->base_cache_used += c->size; + prune_base_data(c); + } + free(delta); + } + return c->data; +} + +static void resolve_delta(struct object_entry *delta_obj, + struct base_data *base, struct base_data *result) +{ + void *base_data, *delta_data; + + delta_obj->real_type = base->obj->real_type; + delta_obj->delta_depth = base->obj->delta_depth + 1; + if (deepest_delta < delta_obj->delta_depth) + deepest_delta = delta_obj->delta_depth; + delta_obj->base_object_no = base->obj - objects; + delta_data = get_data_from_pack(delta_obj); + base_data = get_base_data(base); + result->obj = delta_obj; + result->data = patch_delta(base_data, base->size, + delta_data, delta_obj->size, &result->size); + free(delta_data); + if (!result->data) + bad_object(delta_obj->idx.offset, _("failed to apply delta")); + hash_sha1_file(result->data, result->size, + typename(delta_obj->real_type), delta_obj->idx.sha1); + sha1_object(result->data, NULL, result->size, delta_obj->real_type, + delta_obj->idx.sha1); + counter_lock(); + nr_resolved_deltas++; + counter_unlock(); +} + +static struct base_data *find_unresolved_deltas_1(struct base_data *base, + struct base_data *prev_base) +{ + if (base->ref_last == -1 && base->ofs_last == -1) { + union delta_base base_spec; + + hashcpy(base_spec.sha1, base->obj->idx.sha1); + find_delta_children(&base_spec, + &base->ref_first, &base->ref_last, OBJ_REF_DELTA); + + memset(&base_spec, 0, sizeof(base_spec)); + base_spec.offset = base->obj->idx.offset; + find_delta_children(&base_spec, + &base->ofs_first, &base->ofs_last, OBJ_OFS_DELTA); + + if (base->ref_last == -1 && base->ofs_last == -1) { + free(base->data); + return NULL; + } + + link_base_data(prev_base, base); + } + + if (base->ref_first <= base->ref_last) { + struct object_entry *child = objects + deltas[base->ref_first].obj_no; + struct base_data *result = alloc_base_data(); + + assert(child->real_type == OBJ_REF_DELTA); + resolve_delta(child, base, result); + if (base->ref_first == base->ref_last && base->ofs_last == -1) + free_base_data(base); + + base->ref_first++; + return result; + } + + if (base->ofs_first <= base->ofs_last) { + struct object_entry *child = objects + deltas[base->ofs_first].obj_no; + struct base_data *result = alloc_base_data(); + + assert(child->real_type == OBJ_OFS_DELTA); + resolve_delta(child, base, result); + if (base->ofs_first == base->ofs_last) + free_base_data(base); + + base->ofs_first++; + return result; + } + + unlink_base_data(base); + return NULL; +} + +static void find_unresolved_deltas(struct base_data *base) +{ + struct base_data *new_base, *prev_base = NULL; + for (;;) { + new_base = find_unresolved_deltas_1(base, prev_base); + + if (new_base) { + prev_base = base; + base = new_base; + } else { + free(base); + base = prev_base; + if (!base) + return; + prev_base = base->base; + } + } +} + +static int compare_delta_entry(const void *a, const void *b) +{ + const struct delta_entry *delta_a = a; + const struct delta_entry *delta_b = b; + + /* group by type (ref vs ofs) and then by value (sha-1 or offset) */ + return compare_delta_bases(&delta_a->base, &delta_b->base, + objects[delta_a->obj_no].type, + objects[delta_b->obj_no].type); +} + +static void resolve_base(struct object_entry *obj) +{ + struct base_data *base_obj = alloc_base_data(); + base_obj->obj = obj; + base_obj->data = NULL; + find_unresolved_deltas(base_obj); +} + +#ifndef NO_PTHREADS +static void *threaded_second_pass(void *data) +{ + set_thread_data(data); + for (;;) { + int i; + work_lock(); + display_progress(progress, nr_resolved_deltas); + while (nr_dispatched < nr_objects && + is_delta_type(objects[nr_dispatched].type)) + nr_dispatched++; + if (nr_dispatched >= nr_objects) { + work_unlock(); + break; + } + i = nr_dispatched++; + work_unlock(); + + resolve_base(&objects[i]); + } + return NULL; +} +#endif + +/* + * First pass: + * - find locations of all objects; + * - calculate SHA1 of all non-delta objects; + * - remember base (SHA1 or offset) for all deltas. + */ +static void parse_pack_objects(unsigned char *sha1) +{ + int i, nr_delays = 0; + struct delta_entry *delta = deltas; + struct stat st; + + if (verbose) + progress = start_progress( + from_stdin ? _("Receiving objects") : _("Indexing objects"), + nr_objects); + for (i = 0; i < nr_objects; i++) { + struct object_entry *obj = &objects[i]; + void *data = unpack_raw_entry(obj, &delta->base, obj->idx.sha1); + obj->real_type = obj->type; + if (is_delta_type(obj->type)) { + nr_deltas++; + delta->obj_no = i; + delta++; + } else if (!data) { + /* large blobs, check later */ + obj->real_type = OBJ_BAD; + nr_delays++; + } else + sha1_object(data, NULL, obj->size, obj->type, obj->idx.sha1); + free(data); + display_progress(progress, i+1); + } + objects[i].idx.offset = consumed_bytes; + stop_progress(&progress); + + /* Check pack integrity */ + flush(); + git_SHA1_Final(sha1, &input_ctx); + if (hashcmp(fill(20), sha1)) + die(_("pack is corrupted (SHA1 mismatch)")); + use(20); + + /* If input_fd is a file, we should have reached its end now. */ + if (fstat(input_fd, &st)) + die_errno(_("cannot fstat packfile")); + if (S_ISREG(st.st_mode) && + lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size) + die(_("pack has junk at the end")); + + for (i = 0; i < nr_objects; i++) { + struct object_entry *obj = &objects[i]; + if (obj->real_type != OBJ_BAD) + continue; + obj->real_type = obj->type; + sha1_object(NULL, obj, obj->size, obj->type, obj->idx.sha1); + nr_delays--; + } + if (nr_delays) + die(_("confusion beyond insanity in parse_pack_objects()")); +} + +/* + * Second pass: + * - for all non-delta objects, look if it is used as a base for + * deltas; + * - if used as a base, uncompress the object and apply all deltas, + * recursively checking if the resulting object is used as a base + * for some more deltas. + */ +static void resolve_deltas(void) +{ + int i; + + if (!nr_deltas) + return; + + /* Sort deltas by base SHA1/offset for fast searching */ + qsort(deltas, nr_deltas, sizeof(struct delta_entry), + compare_delta_entry); + + if (verbose) + progress = start_progress(_("Resolving deltas"), nr_deltas); + +#ifndef NO_PTHREADS + nr_dispatched = 0; + if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) { + init_thread(); + for (i = 0; i < nr_threads; i++) { + int ret = pthread_create(&thread_data[i].thread, NULL, + threaded_second_pass, thread_data + i); + if (ret) + die(_("unable to create thread: %s"), + strerror(ret)); + } + for (i = 0; i < nr_threads; i++) + pthread_join(thread_data[i].thread, NULL); + cleanup_thread(); + return; + } +#endif + + for (i = 0; i < nr_objects; i++) { + struct object_entry *obj = &objects[i]; + + if (is_delta_type(obj->type)) + continue; + resolve_base(obj); + display_progress(progress, nr_resolved_deltas); + } +} + +/* + * Third pass: + * - append objects to convert thin pack to full pack if required + * - write the final 20-byte SHA-1 + */ +static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved); +static void conclude_pack(int fix_thin_pack, const char *curr_pack, unsigned char *pack_sha1) +{ + if (nr_deltas == nr_resolved_deltas) { + stop_progress(&progress); + /* Flush remaining pack final 20-byte SHA1. */ + flush(); + return; + } + + if (fix_thin_pack) { + struct sha1file *f; + unsigned char read_sha1[20], tail_sha1[20]; + char msg[48]; + int nr_unresolved = nr_deltas - nr_resolved_deltas; + int nr_objects_initial = nr_objects; + if (nr_unresolved <= 0) + die(_("confusion beyond insanity")); + objects = xrealloc(objects, + (nr_objects + nr_unresolved + 1) + * sizeof(*objects)); + f = sha1fd(output_fd, curr_pack); + fix_unresolved_deltas(f, nr_unresolved); + sprintf(msg, _("completed with %d local objects"), + nr_objects - nr_objects_initial); + stop_progress_msg(&progress, msg); + sha1close(f, tail_sha1, 0); + hashcpy(read_sha1, pack_sha1); + fixup_pack_header_footer(output_fd, pack_sha1, + curr_pack, nr_objects, + read_sha1, consumed_bytes-20); + if (hashcmp(read_sha1, tail_sha1) != 0) + die(_("Unexpected tail checksum for %s " + "(disk corruption?)"), curr_pack); + } + if (nr_deltas != nr_resolved_deltas) + die(Q_("pack has %d unresolved delta", + "pack has %d unresolved deltas", + nr_deltas - nr_resolved_deltas), + nr_deltas - nr_resolved_deltas); +} + +static int write_compressed(struct sha1file *f, void *in, unsigned int size) +{ + git_zstream stream; + int status; + unsigned char outbuf[4096]; + + memset(&stream, 0, sizeof(stream)); + git_deflate_init(&stream, zlib_compression_level); + stream.next_in = in; + stream.avail_in = size; + + do { + stream.next_out = outbuf; + stream.avail_out = sizeof(outbuf); + status = git_deflate(&stream, Z_FINISH); + sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out); + } while (status == Z_OK); + + if (status != Z_STREAM_END) + die(_("unable to deflate appended object (%d)"), status); + size = stream.total_out; + git_deflate_end(&stream); + return size; +} + +static struct object_entry *append_obj_to_pack(struct sha1file *f, + const unsigned char *sha1, void *buf, + unsigned long size, enum object_type type) +{ + struct object_entry *obj = &objects[nr_objects++]; + unsigned char header[10]; + unsigned long s = size; + int n = 0; + unsigned char c = (type << 4) | (s & 15); + s >>= 4; + while (s) { + header[n++] = c | 0x80; + c = s & 0x7f; + s >>= 7; + } + header[n++] = c; + crc32_begin(f); + sha1write(f, header, n); + obj[0].size = size; + obj[0].hdr_size = n; + obj[0].type = type; + obj[0].real_type = type; + obj[1].idx.offset = obj[0].idx.offset + n; + obj[1].idx.offset += write_compressed(f, buf, size); + obj[0].idx.crc32 = crc32_end(f); + sha1flush(f); + hashcpy(obj->idx.sha1, sha1); + return obj; +} + +static int delta_pos_compare(const void *_a, const void *_b) +{ + struct delta_entry *a = *(struct delta_entry **)_a; + struct delta_entry *b = *(struct delta_entry **)_b; + return a->obj_no - b->obj_no; +} + +static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved) +{ + struct delta_entry **sorted_by_pos; + int i, n = 0; + + /* + * Since many unresolved deltas may well be themselves base objects + * for more unresolved deltas, we really want to include the + * smallest number of base objects that would cover as much delta + * as possible by picking the + * trunc deltas first, allowing for other deltas to resolve without + * additional base objects. Since most base objects are to be found + * before deltas depending on them, a good heuristic is to start + * resolving deltas in the same order as their position in the pack. + */ + sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos)); + for (i = 0; i < nr_deltas; i++) { + if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA) + continue; + sorted_by_pos[n++] = &deltas[i]; + } + qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare); + + for (i = 0; i < n; i++) { + struct delta_entry *d = sorted_by_pos[i]; + enum object_type type; + struct base_data *base_obj = alloc_base_data(); + + if (objects[d->obj_no].real_type != OBJ_REF_DELTA) + continue; + base_obj->data = read_sha1_file(d->base.sha1, &type, &base_obj->size); + if (!base_obj->data) + continue; + + if (check_sha1_signature(d->base.sha1, base_obj->data, + base_obj->size, typename(type))) + die(_("local object %s is corrupt"), sha1_to_hex(d->base.sha1)); + base_obj->obj = append_obj_to_pack(f, d->base.sha1, + base_obj->data, base_obj->size, type); + find_unresolved_deltas(base_obj); + display_progress(progress, nr_resolved_deltas); + } + free(sorted_by_pos); +} + +static void final(const char *final_pack_name, const char *curr_pack_name, + const char *final_index_name, const char *curr_index_name, + const char *keep_name, const char *keep_msg, + unsigned char *sha1) +{ + const char *report = "pack"; + char name[PATH_MAX]; + int err; + + if (!from_stdin) { + close(input_fd); + } else { + fsync_or_die(output_fd, curr_pack_name); + err = close(output_fd); + if (err) + die_errno(_("error while closing pack file")); + } + + if (keep_msg) { + int keep_fd, keep_msg_len = strlen(keep_msg); + + if (!keep_name) + keep_fd = odb_pack_keep(name, sizeof(name), sha1); + else + keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600); + + if (keep_fd < 0) { + if (errno != EEXIST) + die_errno(_("cannot write keep file '%s'"), + keep_name); + } else { + if (keep_msg_len > 0) { + write_or_die(keep_fd, keep_msg, keep_msg_len); + write_or_die(keep_fd, "\n", 1); + } + if (close(keep_fd) != 0) + die_errno(_("cannot close written keep file '%s'"), + keep_name); + report = "keep"; + } + } + + if (final_pack_name != curr_pack_name) { + if (!final_pack_name) { + snprintf(name, sizeof(name), "%s/pack/pack-%s.pack", + get_object_directory(), sha1_to_hex(sha1)); + final_pack_name = name; + } + if (move_temp_to_file(curr_pack_name, final_pack_name)) + die(_("cannot store pack file")); + } else if (from_stdin) + chmod(final_pack_name, 0444); + + if (final_index_name != curr_index_name) { + if (!final_index_name) { + snprintf(name, sizeof(name), "%s/pack/pack-%s.idx", + get_object_directory(), sha1_to_hex(sha1)); + final_index_name = name; + } + if (move_temp_to_file(curr_index_name, final_index_name)) + die(_("cannot store index file")); + } else + chmod(final_index_name, 0444); + + if (!from_stdin) { + printf("%s\n", sha1_to_hex(sha1)); + } else { + char buf[48]; + int len = snprintf(buf, sizeof(buf), "%s\t%s\n", + report, sha1_to_hex(sha1)); + write_or_die(1, buf, len); + + /* + * Let's just mimic git-unpack-objects here and write + * the last part of the input buffer to stdout. + */ + while (input_len) { + err = xwrite(1, input_buffer + input_offset, input_len); + if (err <= 0) + break; + input_len -= err; + input_offset += err; + } + } +} + +static int git_index_pack_config(const char *k, const char *v, void *cb) +{ + struct pack_idx_option *opts = cb; + + if (!strcmp(k, "pack.indexversion")) { + opts->version = git_config_int(k, v); + if (opts->version > 2) + die(_("bad pack.indexversion=%"PRIu32), opts->version); + return 0; + } + if (!strcmp(k, "pack.threads")) { + nr_threads = git_config_int(k, v); + if (nr_threads < 0) + die(_("invalid number of threads specified (%d)"), + nr_threads); +#ifdef NO_PTHREADS + if (nr_threads != 1) + warning(_("no threads support, ignoring %s"), k); + nr_threads = 1; +#endif + return 0; + } + return git_default_config(k, v, cb); +} + +static int cmp_uint32(const void *a_, const void *b_) +{ + uint32_t a = *((uint32_t *)a_); + uint32_t b = *((uint32_t *)b_); + + return (a < b) ? -1 : (a != b); +} + +static void read_v2_anomalous_offsets(struct packed_git *p, + struct pack_idx_option *opts) +{ + const uint32_t *idx1, *idx2; + uint32_t i; + + /* The address of the 4-byte offset table */ + idx1 = (((const uint32_t *)p->index_data) + + 2 /* 8-byte header */ + + 256 /* fan out */ + + 5 * p->num_objects /* 20-byte SHA-1 table */ + + p->num_objects /* CRC32 table */ + ); + + /* The address of the 8-byte offset table */ + idx2 = idx1 + p->num_objects; + + for (i = 0; i < p->num_objects; i++) { + uint32_t off = ntohl(idx1[i]); + if (!(off & 0x80000000)) + continue; + off = off & 0x7fffffff; + if (idx2[off * 2]) + continue; + /* + * The real offset is ntohl(idx2[off * 2]) in high 4 + * octets, and ntohl(idx2[off * 2 + 1]) in low 4 + * octets. But idx2[off * 2] is Zero!!! + */ + ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc); + opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]); + } + + if (1 < opts->anomaly_nr) + qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32); +} + +static void read_idx_option(struct pack_idx_option *opts, const char *pack_name) +{ + struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1); + + if (!p) + die(_("Cannot open existing pack file '%s'"), pack_name); + if (open_pack_index(p)) + die(_("Cannot open existing pack idx file for '%s'"), pack_name); + + /* Read the attributes from the existing idx file */ + opts->version = p->index_version; + + if (opts->version == 2) + read_v2_anomalous_offsets(p, opts); + + /* + * Get rid of the idx file as we do not need it anymore. + * NEEDSWORK: extract this bit from free_pack_by_name() in + * sha1_file.c, perhaps? It shouldn't matter very much as we + * know we haven't installed this pack (hence we never have + * read anything from it). + */ + close_pack_index(p); + free(p); +} + +static void show_pack_info(int stat_only) +{ + int i, baseobjects = nr_objects - nr_deltas; + unsigned long *chain_histogram = NULL; + + if (deepest_delta) + chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long)); + + for (i = 0; i < nr_objects; i++) { + struct object_entry *obj = &objects[i]; + + if (is_delta_type(obj->type)) + chain_histogram[obj->delta_depth - 1]++; + if (stat_only) + continue; + printf("%s %-6s %lu %lu %"PRIuMAX, + sha1_to_hex(obj->idx.sha1), + typename(obj->real_type), obj->size, + (unsigned long)(obj[1].idx.offset - obj->idx.offset), + (uintmax_t)obj->idx.offset); + if (is_delta_type(obj->type)) { + struct object_entry *bobj = &objects[obj->base_object_no]; + printf(" %u %s", obj->delta_depth, sha1_to_hex(bobj->idx.sha1)); + } + putchar('\n'); + } + + if (baseobjects) + printf_ln(Q_("non delta: %d object", + "non delta: %d objects", + baseobjects), + baseobjects); + for (i = 0; i < deepest_delta; i++) { + if (!chain_histogram[i]) + continue; + printf_ln(Q_("chain length = %d: %lu object", + "chain length = %d: %lu objects", + chain_histogram[i]), + i + 1, + chain_histogram[i]); + } +} + +int cmd_index_pack(int argc, const char **argv, const char *prefix) +{ + int i, fix_thin_pack = 0, verify = 0, stat_only = 0, stat = 0; + const char *curr_pack, *curr_index; + const char *index_name = NULL, *pack_name = NULL; + const char *keep_name = NULL, *keep_msg = NULL; + char *index_name_buf = NULL, *keep_name_buf = NULL; + struct pack_idx_entry **idx_objects; + struct pack_idx_option opts; + unsigned char pack_sha1[20]; + + if (argc == 2 && !strcmp(argv[1], "-h")) + usage(index_pack_usage); + + read_replace_refs = 0; + + reset_pack_idx_option(&opts); + git_config(git_index_pack_config, &opts); + if (prefix && chdir(prefix)) + die(_("Cannot come back to cwd")); + + for (i = 1; i < argc; i++) { + const char *arg = argv[i]; + + if (*arg == '-') { + if (!strcmp(arg, "--stdin")) { + from_stdin = 1; + } else if (!strcmp(arg, "--fix-thin")) { + fix_thin_pack = 1; + } else if (!strcmp(arg, "--strict")) { + strict = 1; + } else if (!strcmp(arg, "--verify")) { + verify = 1; + } else if (!strcmp(arg, "--verify-stat")) { + verify = 1; + stat = 1; + } else if (!strcmp(arg, "--verify-stat-only")) { + verify = 1; + stat = 1; + stat_only = 1; + } else if (!strcmp(arg, "--keep")) { + keep_msg = ""; + } else if (!prefixcmp(arg, "--keep=")) { + keep_msg = arg + 7; + } else if (!prefixcmp(arg, "--threads=")) { + char *end; + nr_threads = strtoul(arg+10, &end, 0); + if (!arg[10] || *end || nr_threads < 0) + usage(index_pack_usage); +#ifdef NO_PTHREADS + if (nr_threads != 1) + warning(_("no threads support, " + "ignoring %s"), arg); + nr_threads = 1; +#endif + } else if (!prefixcmp(arg, "--pack_header=")) { + struct pack_header *hdr; + char *c; + + hdr = (struct pack_header *)input_buffer; + hdr->hdr_signature = htonl(PACK_SIGNATURE); + hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10)); + if (*c != ',') + die(_("bad %s"), arg); + hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10)); + if (*c) + die(_("bad %s"), arg); + input_len = sizeof(*hdr); + } else if (!strcmp(arg, "-v")) { + verbose = 1; + } else if (!strcmp(arg, "-o")) { + if (index_name || (i+1) >= argc) + usage(index_pack_usage); + index_name = argv[++i]; + } else if (!prefixcmp(arg, "--index-version=")) { + char *c; + opts.version = strtoul(arg + 16, &c, 10); + if (opts.version > 2) + die(_("bad %s"), arg); + if (*c == ',') + opts.off32_limit = strtoul(c+1, &c, 0); + if (*c || opts.off32_limit & 0x80000000) + die(_("bad %s"), arg); + } else + usage(index_pack_usage); + continue; + } + + if (pack_name) + usage(index_pack_usage); + pack_name = arg; + } + + if (!pack_name && !from_stdin) + usage(index_pack_usage); + if (fix_thin_pack && !from_stdin) + die(_("--fix-thin cannot be used without --stdin")); + if (!index_name && pack_name) { + int len = strlen(pack_name); + if (!has_extension(pack_name, ".pack")) + die(_("packfile name '%s' does not end with '.pack'"), + pack_name); + index_name_buf = xmalloc(len); + memcpy(index_name_buf, pack_name, len - 5); + strcpy(index_name_buf + len - 5, ".idx"); + index_name = index_name_buf; + } + if (keep_msg && !keep_name && pack_name) { + int len = strlen(pack_name); + if (!has_extension(pack_name, ".pack")) + die(_("packfile name '%s' does not end with '.pack'"), + pack_name); + keep_name_buf = xmalloc(len); + memcpy(keep_name_buf, pack_name, len - 5); + strcpy(keep_name_buf + len - 5, ".keep"); + keep_name = keep_name_buf; + } + if (verify) { + if (!index_name) + die(_("--verify with no packfile name given")); + read_idx_option(&opts, index_name); + opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT; + } + if (strict) + opts.flags |= WRITE_IDX_STRICT; + +#ifndef NO_PTHREADS + if (!nr_threads) { + nr_threads = online_cpus(); + /* An experiment showed that more threads does not mean faster */ + if (nr_threads > 3) + nr_threads = 3; + } +#endif + + curr_pack = open_pack_file(pack_name); + parse_pack_header(); + objects = xcalloc(nr_objects + 1, sizeof(struct object_entry)); + deltas = xcalloc(nr_objects, sizeof(struct delta_entry)); + parse_pack_objects(pack_sha1); + resolve_deltas(); + conclude_pack(fix_thin_pack, curr_pack, pack_sha1); + free(deltas); + if (strict) + check_objects(); + + if (stat) + show_pack_info(stat_only); + + idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *)); + for (i = 0; i < nr_objects; i++) + idx_objects[i] = &objects[i].idx; + curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1); + free(idx_objects); + + if (!verify) + final(pack_name, curr_pack, + index_name, curr_index, + keep_name, keep_msg, + pack_sha1); + else + close(input_fd); + free(objects); + free(index_name_buf); + free(keep_name_buf); + if (pack_name == NULL) + free((void *) curr_pack); + if (index_name == NULL) + free((void *) curr_index); + + return 0; +} |