diff options
Diffstat (limited to 'sha1_file.c')
-rw-r--r-- | sha1_file.c | 370 |
1 files changed, 221 insertions, 149 deletions
diff --git a/sha1_file.c b/sha1_file.c index d5e11217f5..94daf31ec6 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -23,6 +23,9 @@ #include "bulk-checkin.h" #include "streaming.h" #include "dir.h" +#include "mru.h" +#include "list.h" +#include "mergesort.h" #ifndef O_NOATIME #if defined(__linux__) && (defined(__i386__) || defined(__PPC__)) @@ -37,6 +40,12 @@ static inline uintmax_t sz_fmt(size_t s) { return s; } const unsigned char null_sha1[20]; const struct object_id null_oid; +const struct object_id empty_tree_oid = { + EMPTY_TREE_SHA1_BIN_LITERAL +}; +const struct object_id empty_blob_oid = { + EMPTY_BLOB_SHA1_BIN_LITERAL +}; /* * This is meant to hold a *small* number of objects that you would @@ -59,14 +68,6 @@ static struct cached_object empty_tree = { 0 }; -/* - * A pointer to the last packed_git in which an object was found. - * When an object is sought, we look in this packfile first, because - * objects that are looked up at similar times are often in the same - * packfile as one another. - */ -static struct packed_git *last_found_pack; - static struct cached_object *find_cached_object(const unsigned char *sha1) { int i; @@ -425,6 +426,82 @@ void add_to_alternates_file(const char *reference) free(alts); } +/* + * Compute the exact path an alternate is at and returns it. In case of + * error NULL is returned and the human readable error is added to `err` + * `path` may be relative and should point to $GITDIR. + * `err` must not be null. + */ +char *compute_alternate_path(const char *path, struct strbuf *err) +{ + char *ref_git = NULL; + const char *repo, *ref_git_s; + int seen_error = 0; + + ref_git_s = real_path_if_valid(path); + if (!ref_git_s) { + seen_error = 1; + strbuf_addf(err, _("path '%s' does not exist"), path); + goto out; + } else + /* + * Beware: read_gitfile(), real_path() and mkpath() + * return static buffer + */ + ref_git = xstrdup(ref_git_s); + + repo = read_gitfile(ref_git); + if (!repo) + repo = read_gitfile(mkpath("%s/.git", ref_git)); + if (repo) { + free(ref_git); + ref_git = xstrdup(repo); + } + + if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) { + char *ref_git_git = mkpathdup("%s/.git", ref_git); + free(ref_git); + ref_git = ref_git_git; + } else if (!is_directory(mkpath("%s/objects", ref_git))) { + struct strbuf sb = STRBUF_INIT; + seen_error = 1; + if (get_common_dir(&sb, ref_git)) { + strbuf_addf(err, + _("reference repository '%s' as a linked " + "checkout is not supported yet."), + path); + goto out; + } + + strbuf_addf(err, _("reference repository '%s' is not a " + "local repository."), path); + goto out; + } + + if (!access(mkpath("%s/shallow", ref_git), F_OK)) { + strbuf_addf(err, _("reference repository '%s' is shallow"), + path); + seen_error = 1; + goto out; + } + + if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) { + strbuf_addf(err, + _("reference repository '%s' is grafted"), + path); + seen_error = 1; + goto out; + } + +out: + if (seen_error) { + free(ref_git); + ref_git = NULL; + } + + return ref_git; +} + int foreach_alt_odb(alt_odb_fn fn, void *cb) { struct alternate_object_database *ent; @@ -522,6 +599,9 @@ static size_t peak_pack_mapped; static size_t pack_mapped; struct packed_git *packed_git; +static struct mru packed_git_mru_storage; +struct mru *packed_git_mru = &packed_git_mru_storage; + void pack_report(void) { fprintf(stderr, @@ -795,7 +875,7 @@ void close_all_packs(void) for (p = packed_git; p; p = p->next) if (p->do_not_close) - die("BUG! Want to close pack marked 'do-not-close'"); + die("BUG: want to close pack marked 'do-not-close'"); else close_pack(p); } @@ -891,36 +971,6 @@ void close_pack_index(struct packed_git *p) } } -/* - * This is used by git-repack in case a newly created pack happens to - * contain the same set of objects as an existing one. In that case - * the resulting file might be different even if its name would be the - * same. It is best to close any reference to the old pack before it is - * replaced on disk. Of course no index pointers or windows for given pack - * must subsist at this point. If ever objects from this pack are requested - * again, the new version of the pack will be reinitialized through - * reprepare_packed_git(). - */ -void free_pack_by_name(const char *pack_name) -{ - struct packed_git *p, **pp = &packed_git; - - while (*pp) { - p = *pp; - if (strcmp(pack_name, p->pack_name) == 0) { - clear_delta_base_cache(); - close_pack(p); - free(p->bad_object_sha1); - *pp = p->next; - if (last_found_pack == p) - last_found_pack = NULL; - free(p); - return; - } - pp = &p->next; - } -} - static unsigned int get_max_fd_limit(void) { #ifdef RLIMIT_NOFILE @@ -1331,10 +1381,20 @@ static void prepare_packed_git_one(char *objdir, int local) strbuf_release(&path); } +static void *get_next_packed_git(const void *p) +{ + return ((const struct packed_git *)p)->next; +} + +static void set_next_packed_git(void *p, void *next) +{ + ((struct packed_git *)p)->next = next; +} + static int sort_pack(const void *a_, const void *b_) { - struct packed_git *a = *((struct packed_git **)a_); - struct packed_git *b = *((struct packed_git **)b_); + const struct packed_git *a = a_; + const struct packed_git *b = b_; int st; /* @@ -1361,28 +1421,17 @@ static int sort_pack(const void *a_, const void *b_) static void rearrange_packed_git(void) { - struct packed_git **ary, *p; - int i, n; - - for (n = 0, p = packed_git; p; p = p->next) - n++; - if (n < 2) - return; - - /* prepare an array of packed_git for easier sorting */ - ary = xcalloc(n, sizeof(struct packed_git *)); - for (n = 0, p = packed_git; p; p = p->next) - ary[n++] = p; - - qsort(ary, n, sizeof(struct packed_git *), sort_pack); + packed_git = llist_mergesort(packed_git, get_next_packed_git, + set_next_packed_git, sort_pack); +} - /* link them back again */ - for (i = 0; i < n - 1; i++) - ary[i]->next = ary[i + 1]; - ary[n - 1]->next = NULL; - packed_git = ary[0]; +static void prepare_packed_git_mru(void) +{ + struct packed_git *p; - free(ary); + mru_clear(packed_git_mru); + for (p = packed_git; p; p = p->next) + mru_append(packed_git_mru, p); } static int prepare_packed_git_run_once = 0; @@ -1400,6 +1449,7 @@ void prepare_packed_git(void) alt->name[-1] = '/'; } rearrange_packed_git(); + prepare_packed_git_mru(); prepare_packed_git_run_once = 1; } @@ -1596,7 +1646,9 @@ unsigned long unpack_object_header_buffer(const unsigned char *buf, return used; } -int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz) +static int unpack_sha1_short_header(git_zstream *stream, + unsigned char *map, unsigned long mapsize, + void *buffer, unsigned long bufsiz) { /* Get the data stream */ memset(stream, 0, sizeof(*stream)); @@ -1609,13 +1661,31 @@ int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long ma return git_inflate(stream, 0); } +int unpack_sha1_header(git_zstream *stream, + unsigned char *map, unsigned long mapsize, + void *buffer, unsigned long bufsiz) +{ + int status = unpack_sha1_short_header(stream, map, mapsize, + buffer, bufsiz); + + if (status < Z_OK) + return status; + + /* Make sure we have the terminating NUL */ + if (!memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer)) + return -1; + return 0; +} + static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz, struct strbuf *header) { int status; - status = unpack_sha1_header(stream, map, mapsize, buffer, bufsiz); + status = unpack_sha1_short_header(stream, map, mapsize, buffer, bufsiz); + if (status < Z_OK) + return -1; /* * Check if entire header is unpacked in the first iteration. @@ -1706,6 +1776,8 @@ static int parse_sha1_header_extended(const char *hdr, struct object_info *oi, */ for (;;) { char c = *hdr++; + if (!c) + return -1; if (c == ' ') break; type_len++; @@ -1716,7 +1788,7 @@ static int parse_sha1_header_extended(const char *hdr, struct object_info *oi, strbuf_add(oi->typename, type_buf, type_len); /* * Set type to 0 if its an unknown object and - * we're obtaining the type using '--allow-unkown-type' + * we're obtaining the type using '--allow-unknown-type' * option. */ if ((flags & LOOKUP_UNKNOWN_OBJECT) && (type < 0)) @@ -2097,136 +2169,142 @@ static void *unpack_compressed_entry(struct packed_git *p, return buffer; } -#define MAX_DELTA_CACHE (256) - +static struct hashmap delta_base_cache; static size_t delta_base_cached; -static struct delta_base_cache_lru_list { - struct delta_base_cache_lru_list *prev; - struct delta_base_cache_lru_list *next; -} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru }; +static LIST_HEAD(delta_base_cache_lru); -static struct delta_base_cache_entry { - struct delta_base_cache_lru_list lru; - void *data; +struct delta_base_cache_key { struct packed_git *p; off_t base_offset; +}; + +struct delta_base_cache_entry { + struct hashmap hash; + struct delta_base_cache_key key; + struct list_head lru; + void *data; unsigned long size; enum object_type type; -} delta_base_cache[MAX_DELTA_CACHE]; +}; -static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset) +static unsigned int pack_entry_hash(struct packed_git *p, off_t base_offset) { - unsigned long hash; + unsigned int hash; - hash = (unsigned long)(intptr_t)p + (unsigned long)base_offset; + hash = (unsigned int)(intptr_t)p + (unsigned int)base_offset; hash += (hash >> 8) + (hash >> 16); - return hash % MAX_DELTA_CACHE; + return hash; } static struct delta_base_cache_entry * get_delta_base_cache_entry(struct packed_git *p, off_t base_offset) { - unsigned long hash = pack_entry_hash(p, base_offset); - return delta_base_cache + hash; + struct hashmap_entry entry; + struct delta_base_cache_key key; + + if (!delta_base_cache.cmpfn) + return NULL; + + hashmap_entry_init(&entry, pack_entry_hash(p, base_offset)); + key.p = p; + key.base_offset = base_offset; + return hashmap_get(&delta_base_cache, &entry, &key); +} + +static int delta_base_cache_key_eq(const struct delta_base_cache_key *a, + const struct delta_base_cache_key *b) +{ + return a->p == b->p && a->base_offset == b->base_offset; } -static int eq_delta_base_cache_entry(struct delta_base_cache_entry *ent, - struct packed_git *p, off_t base_offset) +static int delta_base_cache_hash_cmp(const void *va, const void *vb, + const void *vkey) { - return (ent->data && ent->p == p && ent->base_offset == base_offset); + const struct delta_base_cache_entry *a = va, *b = vb; + const struct delta_base_cache_key *key = vkey; + if (key) + return !delta_base_cache_key_eq(&a->key, key); + else + return !delta_base_cache_key_eq(&a->key, &b->key); } static int in_delta_base_cache(struct packed_git *p, off_t base_offset) { - struct delta_base_cache_entry *ent; - ent = get_delta_base_cache_entry(p, base_offset); - return eq_delta_base_cache_entry(ent, p, base_offset); + return !!get_delta_base_cache_entry(p, base_offset); } -static void clear_delta_base_cache_entry(struct delta_base_cache_entry *ent) +/* + * Remove the entry from the cache, but do _not_ free the associated + * entry data. The caller takes ownership of the "data" buffer, and + * should copy out any fields it wants before detaching. + */ +static void detach_delta_base_cache_entry(struct delta_base_cache_entry *ent) { - ent->data = NULL; - ent->lru.next->prev = ent->lru.prev; - ent->lru.prev->next = ent->lru.next; + hashmap_remove(&delta_base_cache, ent, &ent->key); + list_del(&ent->lru); delta_base_cached -= ent->size; + free(ent); } static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset, - unsigned long *base_size, enum object_type *type, int keep_cache) + unsigned long *base_size, enum object_type *type) { struct delta_base_cache_entry *ent; - void *ret; ent = get_delta_base_cache_entry(p, base_offset); - - if (!eq_delta_base_cache_entry(ent, p, base_offset)) + if (!ent) return unpack_entry(p, base_offset, type, base_size); - ret = ent->data; - - if (!keep_cache) - clear_delta_base_cache_entry(ent); - else - ret = xmemdupz(ent->data, ent->size); *type = ent->type; *base_size = ent->size; - return ret; + return xmemdupz(ent->data, ent->size); } static inline void release_delta_base_cache(struct delta_base_cache_entry *ent) { - if (ent->data) { - free(ent->data); - ent->data = NULL; - ent->lru.next->prev = ent->lru.prev; - ent->lru.prev->next = ent->lru.next; - delta_base_cached -= ent->size; - } + free(ent->data); + detach_delta_base_cache_entry(ent); } void clear_delta_base_cache(void) { - unsigned long p; - for (p = 0; p < MAX_DELTA_CACHE; p++) - release_delta_base_cache(&delta_base_cache[p]); + struct hashmap_iter iter; + struct delta_base_cache_entry *entry; + for (entry = hashmap_iter_first(&delta_base_cache, &iter); + entry; + entry = hashmap_iter_next(&iter)) { + release_delta_base_cache(entry); + } } static void add_delta_base_cache(struct packed_git *p, off_t base_offset, void *base, unsigned long base_size, enum object_type type) { - unsigned long hash = pack_entry_hash(p, base_offset); - struct delta_base_cache_entry *ent = delta_base_cache + hash; - struct delta_base_cache_lru_list *lru; + struct delta_base_cache_entry *ent = xmalloc(sizeof(*ent)); + struct list_head *lru, *tmp; - release_delta_base_cache(ent); delta_base_cached += base_size; - for (lru = delta_base_cache_lru.next; - delta_base_cached > delta_base_cache_limit - && lru != &delta_base_cache_lru; - lru = lru->next) { - struct delta_base_cache_entry *f = (void *)lru; - if (f->type == OBJ_BLOB) - release_delta_base_cache(f); - } - for (lru = delta_base_cache_lru.next; - delta_base_cached > delta_base_cache_limit - && lru != &delta_base_cache_lru; - lru = lru->next) { - struct delta_base_cache_entry *f = (void *)lru; + list_for_each_safe(lru, tmp, &delta_base_cache_lru) { + struct delta_base_cache_entry *f = + list_entry(lru, struct delta_base_cache_entry, lru); + if (delta_base_cached <= delta_base_cache_limit) + break; release_delta_base_cache(f); } - ent->p = p; - ent->base_offset = base_offset; + ent->key.p = p; + ent->key.base_offset = base_offset; ent->type = type; ent->data = base; ent->size = base_size; - ent->lru.next = &delta_base_cache_lru; - ent->lru.prev = delta_base_cache_lru.prev; - delta_base_cache_lru.prev->next = &ent->lru; - delta_base_cache_lru.prev = &ent->lru; + list_add_tail(&ent->lru, &delta_base_cache_lru); + + if (!delta_base_cache.cmpfn) + hashmap_init(&delta_base_cache, delta_base_cache_hash_cmp, 0); + hashmap_entry_init(ent, pack_entry_hash(p, base_offset)); + hashmap_add(&delta_base_cache, ent); } static void *read_object(const unsigned char *sha1, enum object_type *type, @@ -2270,18 +2348,18 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset, struct delta_base_cache_entry *ent; ent = get_delta_base_cache_entry(p, curpos); - if (eq_delta_base_cache_entry(ent, p, curpos)) { + if (ent) { type = ent->type; data = ent->data; size = ent->size; - clear_delta_base_cache_entry(ent); + detach_delta_base_cache_entry(ent); base_from_cache = 1; break; } if (do_check_packed_object_crc && p->index_version > 1) { struct revindex_entry *revidx = find_pack_revindex(p, obj_offset); - unsigned long len = revidx[1].offset - obj_offset; + off_t len = revidx[1].offset - obj_offset; if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) { const unsigned char *sha1 = nth_packed_object_sha1(p, revidx->nr); @@ -2330,7 +2408,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset, case OBJ_OFS_DELTA: case OBJ_REF_DELTA: if (data) - die("BUG in unpack_entry: left loop at a valid delta"); + die("BUG: unpack_entry: left loop at a valid delta"); break; case OBJ_COMMIT: case OBJ_TREE: @@ -2604,21 +2682,15 @@ static int fill_pack_entry(const unsigned char *sha1, */ static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e) { - struct packed_git *p; + struct mru_entry *p; prepare_packed_git(); if (!packed_git) return 0; - if (last_found_pack && fill_pack_entry(sha1, e, last_found_pack)) - return 1; - - for (p = packed_git; p; p = p->next) { - if (p == last_found_pack) - continue; /* we already checked this one */ - - if (fill_pack_entry(sha1, e, p)) { - last_found_pack = p; + for (p = packed_git_mru->head; p; p = p->next) { + if (fill_pack_entry(sha1, e, p->item)) { + mru_mark(packed_git_mru, p); return 1; } } @@ -2785,7 +2857,7 @@ static void *read_packed_sha1(const unsigned char *sha1, if (!find_pack_entry(sha1, &e)) return NULL; - data = cache_or_unpack_entry(e.p, e.offset, size, type, 1); + data = cache_or_unpack_entry(e.p, e.offset, size, type); if (!data) { /* * We're probably in deep shit, but let's try to fetch |