diff options
Diffstat (limited to 'sha1_file.c')
| -rw-r--r-- | sha1_file.c | 3200 |
1 files changed, 2165 insertions, 1035 deletions
diff --git a/sha1_file.c b/sha1_file.c index a80d849f15..e002056b85 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -9,6 +9,15 @@ #include "cache.h" #include "delta.h" #include "pack.h" +#include "blob.h" +#include "commit.h" +#include "run-command.h" +#include "tag.h" +#include "tree.h" +#include "tree-walk.h" +#include "refs.h" +#include "pack-revindex.h" +#include "sha1-lookup.h" #ifndef O_NOATIME #if defined(__linux__) && (defined(__i386__) || defined(__PPC__)) @@ -18,70 +27,89 @@ #endif #endif -const unsigned char null_sha1[20] = { 0, }; +#define SZ_FMT PRIuMAX +static inline uintmax_t sz_fmt(size_t s) { return s; } -static unsigned int sha1_file_open_flag = O_NOATIME; +const unsigned char null_sha1[20]; -static unsigned hexval(char c) -{ - if (c >= '0' && c <= '9') - return c - '0'; - if (c >= 'a' && c <= 'f') - return c - 'a' + 10; - if (c >= 'A' && c <= 'F') - return c - 'A' + 10; - return ~0; -} +/* + * This is meant to hold a *small* number of objects that you would + * want read_sha1_file() to be able to return, but yet you do not want + * to write them into the object store (e.g. a browse-only + * application). + */ +static struct cached_object { + unsigned char sha1[20]; + enum object_type type; + void *buf; + unsigned long size; +} *cached_objects; +static int cached_object_nr, cached_object_alloc; -int get_sha1_hex(const char *hex, unsigned char *sha1) +static struct cached_object empty_tree = { + EMPTY_TREE_SHA1_BIN_LITERAL, + OBJ_TREE, + "", + 0 +}; + +static struct cached_object *find_cached_object(const unsigned char *sha1) { int i; - for (i = 0; i < 20; i++) { - unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]); - if (val & ~0xff) - return -1; - *sha1++ = val; - hex += 2; + struct cached_object *co = cached_objects; + + for (i = 0; i < cached_object_nr; i++, co++) { + if (!hashcmp(co->sha1, sha1)) + return co; } - return 0; + if (!hashcmp(sha1, empty_tree.sha1)) + return &empty_tree; + return NULL; } -int adjust_shared_perm(const char *path) +int mkdir_in_gitdir(const char *path) { - struct stat st; - int mode; + if (mkdir(path, 0777)) { + int saved_errno = errno; + struct stat st; + struct strbuf sb = STRBUF_INIT; - if (!shared_repository) - return 0; - if (lstat(path, &st) < 0) - return -1; - mode = st.st_mode; - if (mode & S_IRUSR) - mode |= S_IRGRP; - if (mode & S_IWUSR) - mode |= S_IWGRP; - if (mode & S_IXUSR) - mode |= S_IXGRP; - if (S_ISDIR(mode)) - mode |= S_ISGID; - if (chmod(path, mode) < 0) - return -2; - return 0; + if (errno != EEXIST) + return -1; + /* + * Are we looking at a path in a symlinked worktree + * whose original repository does not yet have it? + * e.g. .git/rr-cache pointing at its original + * repository in which the user hasn't performed any + * conflict resolution yet? + */ + if (lstat(path, &st) || !S_ISLNK(st.st_mode) || + strbuf_readlink(&sb, path, st.st_size) || + !is_absolute_path(sb.buf) || + mkdir(sb.buf, 0777)) { + strbuf_release(&sb); + errno = saved_errno; + return -1; + } + strbuf_release(&sb); + } + return adjust_shared_perm(path); } int safe_create_leading_directories(char *path) { - char *pos = path; + char *pos = path + offset_1st_component(path); struct stat st; - if (*pos == '/') - pos++; - while (pos) { pos = strchr(pos, '/'); if (!pos) break; - *pos = 0; + while (*++pos == '/') + ; + if (!*pos) + break; + *--pos = '\0'; if (!stat(path, &st)) { /* path exists */ if (!S_ISDIR(st.st_mode)) { @@ -102,21 +130,13 @@ int safe_create_leading_directories(char *path) return 0; } -char * sha1_to_hex(const unsigned char *sha1) +int safe_create_leading_directories_const(const char *path) { - static char buffer[50]; - static const char hex[] = "0123456789abcdef"; - char *buf = buffer; - int i; - - for (i = 0; i < 20; i++) { - unsigned int val = *sha1++; - *buf++ = hex[val >> 4]; - *buf++ = hex[val & 0xf]; - } - *buf = '\0'; - - return buffer; + /* path points to cache entries, so xstrdup before messing with it */ + char *buf = xstrdup(path); + int result = safe_create_leading_directories(buf); + free(buf); + return result; } static void fill_sha1_path(char *pathbuf, const unsigned char *sha1) @@ -133,7 +153,7 @@ static void fill_sha1_path(char *pathbuf, const unsigned char *sha1) /* * NOTE! This returns a statically allocated buffer, so you have to be - * careful about using it. Do a "strdup()" if you need to save the + * careful about using it. Do an "xstrdup()" if you need to save the * filename. * * Also note that this returns the location for creating. Reading @@ -143,75 +163,71 @@ static void fill_sha1_path(char *pathbuf, const unsigned char *sha1) */ char *sha1_file_name(const unsigned char *sha1) { - static char *name, *base; + static char buf[PATH_MAX]; + const char *objdir; + int len; - if (!base) { - const char *sha1_file_directory = get_object_directory(); - int len = strlen(sha1_file_directory); - base = xmalloc(len + 60); - memcpy(base, sha1_file_directory, len); - memset(base+len, 0, 60); - base[len] = '/'; - base[len+3] = '/'; - name = base + len + 1; - } - fill_sha1_path(name, sha1); - return base; + objdir = get_object_directory(); + len = strlen(objdir); + + /* '/' + sha1(2) + '/' + sha1(38) + '\0' */ + if (len + 43 > PATH_MAX) + die("insanely long object directory %s", objdir); + memcpy(buf, objdir, len); + buf[len] = '/'; + buf[len+3] = '/'; + buf[len+42] = '\0'; + fill_sha1_path(buf + len + 1, sha1); + return buf; } -char *sha1_pack_name(const unsigned char *sha1) +static char *sha1_get_pack_name(const unsigned char *sha1, + char **name, char **base, const char *which) { static const char hex[] = "0123456789abcdef"; - static char *name, *base, *buf; + char *buf; int i; - if (!base) { + if (!*base) { const char *sha1_file_directory = get_object_directory(); int len = strlen(sha1_file_directory); - base = xmalloc(len + 60); - sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory); - name = base + len + 11; + *base = xmalloc(len + 60); + sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s", + sha1_file_directory, which); + *name = *base + len + 11; } - buf = name; + buf = *name; for (i = 0; i < 20; i++) { unsigned int val = *sha1++; *buf++ = hex[val >> 4]; *buf++ = hex[val & 0xf]; } - - return base; + + return *base; } -char *sha1_pack_index_name(const unsigned char *sha1) +char *sha1_pack_name(const unsigned char *sha1) { - static const char hex[] = "0123456789abcdef"; - static char *name, *base, *buf; - int i; + static char *name, *base; - if (!base) { - const char *sha1_file_directory = get_object_directory(); - int len = strlen(sha1_file_directory); - base = xmalloc(len + 60); - sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory); - name = base + len + 11; - } + return sha1_get_pack_name(sha1, &name, &base, "pack"); +} - buf = name; +char *sha1_pack_index_name(const unsigned char *sha1) +{ + static char *name, *base; - for (i = 0; i < 20; i++) { - unsigned int val = *sha1++; - *buf++ = hex[val >> 4]; - *buf++ = hex[val & 0xf]; - } - - return base; + return sha1_get_pack_name(sha1, &name, &base, "idx"); } struct alternate_object_database *alt_odb_list; static struct alternate_object_database **alt_odb_tail; +static void read_info_alternates(const char * alternates, int depth); +static int git_open_noatime(const char *name); + /* * Prepare alternate object database registry. * @@ -227,14 +243,84 @@ static struct alternate_object_database **alt_odb_tail; * SHA1, an extra slash for the first level indirection, and the * terminating NUL. */ -static void link_alt_odb_entries(const char *alt, const char *ep, int sep, - const char *relative_base) +static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth) { - const char *cp, *last; - struct alternate_object_database *ent; const char *objdir = get_object_directory(); + struct alternate_object_database *ent; + struct alternate_object_database *alt; + /* 43 = 40-byte + 2 '/' + terminating NUL */ + int pfxlen = len; + int entlen = pfxlen + 43; int base_len = -1; + if (!is_absolute_path(entry) && relative_base) { + /* Relative alt-odb */ + if (base_len < 0) + base_len = strlen(relative_base) + 1; + entlen += base_len; + pfxlen += base_len; + } + ent = xmalloc(sizeof(*ent) + entlen); + + if (!is_absolute_path(entry) && relative_base) { + memcpy(ent->base, relative_base, base_len - 1); + ent->base[base_len - 1] = '/'; + memcpy(ent->base + base_len, entry, len); + } + else + memcpy(ent->base, entry, pfxlen); + + ent->name = ent->base + pfxlen + 1; + ent->base[pfxlen + 3] = '/'; + ent->base[pfxlen] = ent->base[entlen-1] = 0; + + /* Detect cases where alternate disappeared */ + if (!is_directory(ent->base)) { + error("object directory %s does not exist; " + "check .git/objects/info/alternates.", + ent->base); + free(ent); + return -1; + } + + /* Prevent the common mistake of listing the same + * thing twice, or object directory itself. + */ + for (alt = alt_odb_list; alt; alt = alt->next) { + if (!memcmp(ent->base, alt->base, pfxlen)) { + free(ent); + return -1; + } + } + if (!memcmp(ent->base, objdir, pfxlen)) { + free(ent); + return -1; + } + + /* add the alternate entry */ + *alt_odb_tail = ent; + alt_odb_tail = &(ent->next); + ent->next = NULL; + + /* recursively add alternates */ + read_info_alternates(ent->base, depth + 1); + + ent->base[pfxlen] = '/'; + + return 0; +} + +static void link_alt_odb_entries(const char *alt, const char *ep, int sep, + const char *relative_base, int depth) +{ + const char *cp, *last; + + if (depth > 5) { + error("%s: ignoring alternate object stores, nesting too deep.", + relative_base); + return; + } + last = alt; while (last < ep) { cp = last; @@ -244,60 +330,15 @@ static void link_alt_odb_entries(const char *alt, const char *ep, int sep, last = cp + 1; continue; } - for ( ; cp < ep && *cp != sep; cp++) - ; + while (cp < ep && *cp != sep) + cp++; if (last != cp) { - struct stat st; - struct alternate_object_database *alt; - /* 43 = 40-byte + 2 '/' + terminating NUL */ - int pfxlen = cp - last; - int entlen = pfxlen + 43; - - if (*last != '/' && relative_base) { - /* Relative alt-odb */ - if (base_len < 0) - base_len = strlen(relative_base) + 1; - entlen += base_len; - pfxlen += base_len; - } - ent = xmalloc(sizeof(*ent) + entlen); - - if (*last != '/' && relative_base) { - memcpy(ent->base, relative_base, base_len - 1); - ent->base[base_len - 1] = '/'; - memcpy(ent->base + base_len, - last, cp - last); - } - else - memcpy(ent->base, last, pfxlen); - - ent->name = ent->base + pfxlen + 1; - ent->base[pfxlen + 3] = '/'; - ent->base[pfxlen] = ent->base[entlen-1] = 0; - - /* Detect cases where alternate disappeared */ - if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) { - error("object directory %s does not exist; " - "check .git/objects/info/alternates.", - ent->base); - goto bad; - } - ent->base[pfxlen] = '/'; - - /* Prevent the common mistake of listing the same - * thing twice, or object directory itself. - */ - for (alt = alt_odb_list; alt; alt = alt->next) - if (!memcmp(ent->base, alt->base, pfxlen)) - goto bad; - if (!memcmp(ent->base, objdir, pfxlen)) { - bad: - free(ent); - } - else { - *alt_odb_tail = ent; - alt_odb_tail = &(ent->next); - ent->next = NULL; + if (!is_absolute_path(last) && depth) { + error("%s: ignoring relative alternate object store %s", + relative_base, last); + } else { + link_alt_odb_entry(last, cp - last, + relative_base, depth); } } while (cp < ep && *cp == sep) @@ -306,255 +347,651 @@ static void link_alt_odb_entries(const char *alt, const char *ep, int sep, } } -void prepare_alt_odb(void) +static void read_info_alternates(const char * relative_base, int depth) { - char path[PATH_MAX]; char *map; - int fd; + size_t mapsz; struct stat st; - char *alt; - - alt = getenv(ALTERNATE_DB_ENVIRONMENT); - if (!alt) alt = ""; - - if (alt_odb_tail) - return; - alt_odb_tail = &alt_odb_list; - link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL); + const char alt_file_name[] = "info/alternates"; + /* Given that relative_base is no longer than PATH_MAX, + ensure that "path" has enough space to append "/", the + file name, "info/alternates", and a trailing NUL. */ + char path[PATH_MAX + 1 + sizeof alt_file_name]; + int fd; - sprintf(path, "%s/info/alternates", get_object_directory()); - fd = open(path, O_RDONLY); + sprintf(path, "%s/%s", relative_base, alt_file_name); + fd = git_open_noatime(path); if (fd < 0) return; if (fstat(fd, &st) || (st.st_size == 0)) { close(fd); return; } - map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + mapsz = xsize_t(st.st_size); + map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0); close(fd); - if (map == MAP_FAILED) + + link_alt_odb_entries(map, map + mapsz, '\n', relative_base, depth); + + munmap(map, mapsz); +} + +void add_to_alternates_file(const char *reference) +{ + struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); + int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR); + char *alt = mkpath("%s\n", reference); + write_or_die(fd, alt, strlen(alt)); + if (commit_lock_file(lock)) + die("could not close alternates file"); + if (alt_odb_tail) + link_alt_odb_entries(alt, alt + strlen(alt), '\n', NULL, 0); +} + +void foreach_alt_odb(alt_odb_fn fn, void *cb) +{ + struct alternate_object_database *ent; + + prepare_alt_odb(); + for (ent = alt_odb_list; ent; ent = ent->next) + if (fn(ent, cb)) + return; +} + +void prepare_alt_odb(void) +{ + const char *alt; + + if (alt_odb_tail) return; - link_alt_odb_entries(map, map + st.st_size, '\n', - get_object_directory()); - munmap(map, st.st_size); + alt = getenv(ALTERNATE_DB_ENVIRONMENT); + if (!alt) alt = ""; + + alt_odb_tail = &alt_odb_list; + link_alt_odb_entries(alt, alt + strlen(alt), PATH_SEP, NULL, 0); + + read_info_alternates(get_object_directory(), 0); } -static char *find_sha1_file(const unsigned char *sha1, struct stat *st) +static int has_loose_object_local(const unsigned char *sha1) { char *name = sha1_file_name(sha1); - struct alternate_object_database *alt; + return !access(name, F_OK); +} - if (!stat(name, st)) - return name; +int has_loose_object_nonlocal(const unsigned char *sha1) +{ + struct alternate_object_database *alt; prepare_alt_odb(); for (alt = alt_odb_list; alt; alt = alt->next) { - name = alt->name; - fill_sha1_path(name, sha1); - if (!stat(alt->base, st)) - return alt->base; + fill_sha1_path(alt->name, sha1); + if (!access(alt->base, F_OK)) + return 1; } - return NULL; + return 0; +} + +static int has_loose_object(const unsigned char *sha1) +{ + return has_loose_object_local(sha1) || + has_loose_object_nonlocal(sha1); } -#define PACK_MAX_SZ (1<<26) -static int pack_used_ctr; -static unsigned long pack_mapped; +static unsigned int pack_used_ctr; +static unsigned int pack_mmap_calls; +static unsigned int peak_pack_open_windows; +static unsigned int pack_open_windows; +static unsigned int pack_open_fds; +static unsigned int pack_max_fds; +static size_t peak_pack_mapped; +static size_t pack_mapped; struct packed_git *packed_git; -static int check_packed_git_idx(const char *path, unsigned long *idx_size_, - void **idx_map_) +void pack_report(void) +{ + fprintf(stderr, + "pack_report: getpagesize() = %10" SZ_FMT "\n" + "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n" + "pack_report: core.packedGitLimit = %10" SZ_FMT "\n", + sz_fmt(getpagesize()), + sz_fmt(packed_git_window_size), + sz_fmt(packed_git_limit)); + fprintf(stderr, + "pack_report: pack_used_ctr = %10u\n" + "pack_report: pack_mmap_calls = %10u\n" + "pack_report: pack_open_windows = %10u / %10u\n" + "pack_report: pack_mapped = " + "%10" SZ_FMT " / %10" SZ_FMT "\n", + pack_used_ctr, + pack_mmap_calls, + pack_open_windows, peak_pack_open_windows, + sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped)); +} + +static int check_packed_git_idx(const char *path, struct packed_git *p) { void *idx_map; - unsigned int *index; - unsigned long idx_size; - int nr, i; - int fd = open(path, O_RDONLY); + struct pack_idx_header *hdr; + size_t idx_size; + uint32_t version, nr, i, *index; + int fd = git_open_noatime(path); struct stat st; + if (fd < 0) return -1; if (fstat(fd, &st)) { close(fd); return -1; } - idx_size = st.st_size; - idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0); + idx_size = xsize_t(st.st_size); + if (idx_size < 4 * 256 + 20 + 20) { + close(fd); + return error("index file %s is too small", path); + } + idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0); close(fd); - if (idx_map == MAP_FAILED) - return -1; - index = idx_map; - *idx_map_ = idx_map; - *idx_size_ = idx_size; + hdr = idx_map; + if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) { + version = ntohl(hdr->idx_version); + if (version < 2 || version > 2) { + munmap(idx_map, idx_size); + return error("index file %s is version %"PRIu32 + " and is not supported by this binary" + " (try upgrading GIT to a newer version)", + path, version); + } + } else + version = 1; - /* check index map */ - if (idx_size < 4*256 + 20 + 20) - return error("index file too small"); nr = 0; + index = idx_map; + if (version > 1) + index += 2; /* skip index header */ for (i = 0; i < 256; i++) { - unsigned int n = ntohl(index[i]); - if (n < nr) - return error("non-monotonic index"); + uint32_t n = ntohl(index[i]); + if (n < nr) { + munmap(idx_map, idx_size); + return error("non-monotonic index %s", path); + } nr = n; } - /* - * Total size: - * - 256 index entries 4 bytes each - * - 24-byte entries * nr (20-byte sha1 + 4-byte offset) - * - 20-byte SHA1 of the packfile - * - 20-byte SHA1 file checksum - */ - if (idx_size != 4*256 + nr * 24 + 20 + 20) - return error("wrong index file size"); + if (version == 1) { + /* + * Total size: + * - 256 index entries 4 bytes each + * - 24-byte entries * nr (20-byte sha1 + 4-byte offset) + * - 20-byte SHA1 of the packfile + * - 20-byte SHA1 file checksum + */ + if (idx_size != 4*256 + nr * 24 + 20 + 20) { + munmap(idx_map, idx_size); + return error("wrong index v1 file size in %s", path); + } + } else if (version == 2) { + /* + * Minimum size: + * - 8 bytes of header + * - 256 index entries 4 bytes each + * - 20-byte sha1 entry * nr + * - 4-byte crc entry * nr + * - 4-byte offset entry * nr + * - 20-byte SHA1 of the packfile + * - 20-byte SHA1 file checksum + * And after the 4-byte offset table might be a + * variable sized table containing 8-byte entries + * for offsets larger than 2^31. + */ + unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20; + unsigned long max_size = min_size; + if (nr) + max_size += (nr - 1)*8; + if (idx_size < min_size || idx_size > max_size) { + munmap(idx_map, idx_size); + return error("wrong index v2 file size in %s", path); + } + if (idx_size != min_size && + /* + * make sure we can deal with large pack offsets. + * 31-bit signed offset won't be enough, neither + * 32-bit unsigned one will be. + */ + (sizeof(off_t) <= 4)) { + munmap(idx_map, idx_size); + return error("pack too large for current definition of off_t in %s", path); + } + } + p->index_version = version; + p->index_data = idx_map; + p->index_size = idx_size; + p->num_objects = nr; return 0; } -static int unuse_one_packed_git(void) +int open_pack_index(struct packed_git *p) { - struct packed_git *p, *lru = NULL; + char *idx_name; + int ret; - for (p = packed_git; p; p = p->next) { - if (p->pack_use_cnt || !p->pack_base) - continue; - if (!lru || p->pack_last_used < lru->pack_last_used) - lru = p; - } - if (!lru) + if (p->index_data) return 0; - munmap(lru->pack_base, lru->pack_size); - lru->pack_base = NULL; - return 1; + + idx_name = xstrdup(p->pack_name); + strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx"); + ret = check_packed_git_idx(idx_name, p); + free(idx_name); + return ret; +} + +static void scan_windows(struct packed_git *p, + struct packed_git **lru_p, + struct pack_window **lru_w, + struct pack_window **lru_l) +{ + struct pack_window *w, *w_l; + + for (w_l = NULL, w = p->windows; w; w = w->next) { + if (!w->inuse_cnt) { + if (!*lru_w || w->last_used < (*lru_w)->last_used) { + *lru_p = p; + *lru_w = w; + *lru_l = w_l; + } + } + w_l = w; + } +} + +static int unuse_one_window(struct packed_git *current, int keep_fd) +{ + struct packed_git *p, *lru_p = NULL; + struct pack_window *lru_w = NULL, *lru_l = NULL; + + if (current) + scan_windows(current, &lru_p, &lru_w, &lru_l); + for (p = packed_git; p; p = p->next) + scan_windows(p, &lru_p, &lru_w, &lru_l); + if (lru_p) { + munmap(lru_w->base, lru_w->len); + pack_mapped -= lru_w->len; + if (lru_l) + lru_l->next = lru_w->next; + else { + lru_p->windows = lru_w->next; + if (!lru_p->windows && lru_p->pack_fd != -1 + && lru_p->pack_fd != keep_fd) { + close(lru_p->pack_fd); + pack_open_fds--; + lru_p->pack_fd = -1; + } + } + free(lru_w); + pack_open_windows--; + return 1; + } + return 0; +} + +void release_pack_memory(size_t need, int fd) +{ + size_t cur = pack_mapped; + while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd)) + ; /* nothing */ +} + +void *xmmap(void *start, size_t length, + int prot, int flags, int fd, off_t offset) +{ + void *ret = mmap(start, length, prot, flags, fd, offset); + if (ret == MAP_FAILED) { + if (!length) + return NULL; + release_pack_memory(length, fd); + ret = mmap(start, length, prot, flags, fd, offset); + if (ret == MAP_FAILED) + die_errno("Out of memory? mmap failed"); + } + return ret; +} + +void close_pack_windows(struct packed_git *p) +{ + while (p->windows) { + struct pack_window *w = p->windows; + + if (w->inuse_cnt) + die("pack '%s' still has open windows to it", + p->pack_name); + munmap(w->base, w->len); + pack_mapped -= w->len; + pack_open_windows--; + p->windows = w->next; + free(w); + } +} + +void unuse_pack(struct pack_window **w_cursor) +{ + struct pack_window *w = *w_cursor; + if (w) { + w->inuse_cnt--; + *w_cursor = NULL; + } +} + +void close_pack_index(struct packed_git *p) +{ + if (p->index_data) { + munmap((void *)p->index_data, p->index_size); + p->index_data = NULL; + } } -void unuse_packed_git(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 nor 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) { - p->pack_use_cnt--; + 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_windows(p); + if (p->pack_fd != -1) { + close(p->pack_fd); + pack_open_fds--; + } + close_pack_index(p); + free(p->bad_object_sha1); + *pp = p->next; + free(p); + return; + } + pp = &p->next; + } } -int use_packed_git(struct packed_git *p) +/* + * Do not call this directly as this leaks p->pack_fd on error return; + * call open_packed_git() instead. + */ +static int open_packed_git_1(struct packed_git *p) { + struct stat st; + struct pack_header hdr; + unsigned char sha1[20]; + unsigned char *idx_sha1; + long fd_flag; + + if (!p->index_data && open_pack_index(p)) + return error("packfile %s index unavailable", p->pack_name); + + if (!pack_max_fds) { + struct rlimit lim; + unsigned int max_fds; + + if (getrlimit(RLIMIT_NOFILE, &lim)) + die_errno("cannot get RLIMIT_NOFILE"); + + max_fds = lim.rlim_cur; + + /* Save 3 for stdin/stdout/stderr, 22 for work */ + if (25 < max_fds) + pack_max_fds = max_fds - 25; + else + pack_max_fds = 1; + } + + while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1)) + ; /* nothing */ + + p->pack_fd = git_open_noatime(p->pack_name); + if (p->pack_fd < 0 || fstat(p->pack_fd, &st)) + return -1; + pack_open_fds++; + + /* If we created the struct before we had the pack we lack size. */ if (!p->pack_size) { - struct stat st; - // We created the struct before we had the pack - stat(p->pack_name, &st); if (!S_ISREG(st.st_mode)) - die("packfile %s not a regular file", p->pack_name); + return error("packfile %s not a regular file", p->pack_name); p->pack_size = st.st_size; + } else if (p->pack_size != st.st_size) + return error("packfile %s size changed", p->pack_name); + + /* We leave these file descriptors open with sliding mmap; + * there is no point keeping them open across exec(), though. + */ + fd_flag = fcntl(p->pack_fd, F_GETFD, 0); + if (fd_flag < 0) + return error("cannot determine file descriptor flags"); + fd_flag |= FD_CLOEXEC; + if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1) + return error("cannot set FD_CLOEXEC"); + + /* Verify we recognize this pack file format. */ + if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr)) + return error("file %s is far too short to be a packfile", p->pack_name); + if (hdr.hdr_signature != htonl(PACK_SIGNATURE)) + return error("file %s is not a GIT packfile", p->pack_name); + if (!pack_version_ok(hdr.hdr_version)) + return error("packfile %s is version %"PRIu32" and not" + " supported (try upgrading GIT to a newer version)", + p->pack_name, ntohl(hdr.hdr_version)); + + /* Verify the pack matches its index. */ + if (p->num_objects != ntohl(hdr.hdr_entries)) + return error("packfile %s claims to have %"PRIu32" objects" + " while index indicates %"PRIu32" objects", + p->pack_name, ntohl(hdr.hdr_entries), + p->num_objects); + if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1) + return error("end of packfile %s is unavailable", p->pack_name); + if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1)) + return error("packfile %s signature is unavailable", p->pack_name); + idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40; + if (hashcmp(sha1, idx_sha1)) + return error("packfile %s does not match index", p->pack_name); + return 0; +} + +static int open_packed_git(struct packed_git *p) +{ + if (!open_packed_git_1(p)) + return 0; + if (p->pack_fd != -1) { + close(p->pack_fd); + pack_open_fds--; + p->pack_fd = -1; } - if (!p->pack_base) { - int fd; - struct stat st; - void *map; + return -1; +} - pack_mapped += p->pack_size; - while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git()) - ; /* nothing */ - fd = open(p->pack_name, O_RDONLY); - if (fd < 0) - die("packfile %s cannot be opened", p->pack_name); - if (fstat(fd, &st)) { - close(fd); - die("packfile %s cannot be opened", p->pack_name); - } - if (st.st_size != p->pack_size) - die("packfile %s size mismatch.", p->pack_name); - map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0); - close(fd); - if (map == MAP_FAILED) - die("packfile %s cannot be mapped.", p->pack_name); - p->pack_base = map; +static int in_window(struct pack_window *win, off_t offset) +{ + /* We must promise at least 20 bytes (one hash) after the + * offset is available from this window, otherwise the offset + * is not actually in this window and a different window (which + * has that one hash excess) must be used. This is to support + * the object header and delta base parsing routines below. + */ + off_t win_off = win->offset; + return win_off <= offset + && (offset + 20) <= (win_off + win->len); +} - /* Check if the pack file matches with the index file. - * this is cheap. - */ - if (memcmp((char*)(p->index_base) + p->index_size - 40, - p->pack_base + p->pack_size - 20, 20)) { - - die("packfile %s does not match index.", p->pack_name); +unsigned char *use_pack(struct packed_git *p, + struct pack_window **w_cursor, + off_t offset, + unsigned long *left) +{ + struct pack_window *win = *w_cursor; + + /* Since packfiles end in a hash of their content and it's + * pointless to ask for an offset into the middle of that + * hash, and the in_window function above wouldn't match + * don't allow an offset too close to the end of the file. + */ + if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p)) + die("packfile %s cannot be accessed", p->pack_name); + if (offset > (p->pack_size - 20)) + die("offset beyond end of packfile (truncated pack?)"); + + if (!win || !in_window(win, offset)) { + if (win) + win->inuse_cnt--; + for (win = p->windows; win; win = win->next) { + if (in_window(win, offset)) + break; + } + if (!win) { + size_t window_align = packed_git_window_size / 2; + off_t len; + + if (p->pack_fd == -1 && open_packed_git(p)) + die("packfile %s cannot be accessed", p->pack_name); + + win = xcalloc(1, sizeof(*win)); + win->offset = (offset / window_align) * window_align; + len = p->pack_size - win->offset; + if (len > packed_git_window_size) + len = packed_git_window_size; + win->len = (size_t)len; + pack_mapped += win->len; + while (packed_git_limit < pack_mapped + && unuse_one_window(p, p->pack_fd)) + ; /* nothing */ + win->base = xmmap(NULL, win->len, + PROT_READ, MAP_PRIVATE, + p->pack_fd, win->offset); + if (win->base == MAP_FAILED) + die("packfile %s cannot be mapped: %s", + p->pack_name, + strerror(errno)); + if (!win->offset && win->len == p->pack_size + && !p->do_not_close) { + close(p->pack_fd); + pack_open_fds--; + p->pack_fd = -1; + } + pack_mmap_calls++; + pack_open_windows++; + if (pack_mapped > peak_pack_mapped) + peak_pack_mapped = pack_mapped; + if (pack_open_windows > peak_pack_open_windows) + peak_pack_open_windows = pack_open_windows; + win->next = p->windows; + p->windows = win; } } - p->pack_last_used = pack_used_ctr++; - p->pack_use_cnt++; - return 0; + if (win != *w_cursor) { + win->last_used = pack_used_ctr++; + win->inuse_cnt++; + *w_cursor = win; + } + offset -= win->offset; + if (left) + *left = win->len - xsize_t(offset); + return win->base + offset; +} + +static struct packed_git *alloc_packed_git(int extra) +{ + struct packed_git *p = xmalloc(sizeof(*p) + extra); + memset(p, 0, sizeof(*p)); + p->pack_fd = -1; + return p; } -struct packed_git *add_packed_git(char *path, int path_len, int local) +static void try_to_free_pack_memory(size_t size) { + release_pack_memory(size, -1); +} + +struct packed_git *add_packed_git(const char *path, int path_len, int local) +{ + static int have_set_try_to_free_routine; struct stat st; - struct packed_git *p; - unsigned long idx_size; - void *idx_map; - unsigned char sha1[20]; + struct packed_git *p = alloc_packed_git(path_len + 2); - if (check_packed_git_idx(path, &idx_size, &idx_map)) + if (!have_set_try_to_free_routine) { + have_set_try_to_free_routine = 1; + set_try_to_free_routine(try_to_free_pack_memory); + } + + /* + * Make sure a corresponding .pack file exists and that + * the index looks sane. + */ + path_len -= strlen(".idx"); + if (path_len < 1) { + free(p); return NULL; + } + memcpy(p->pack_name, path, path_len); + + strcpy(p->pack_name + path_len, ".keep"); + if (!access(p->pack_name, F_OK)) + p->pack_keep = 1; - /* do we have a corresponding .pack file? */ - strcpy(path + path_len - 4, ".pack"); - if (stat(path, &st) || !S_ISREG(st.st_mode)) { - munmap(idx_map, idx_size); + strcpy(p->pack_name + path_len, ".pack"); + if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) { + free(p); return NULL; } + /* ok, it looks sane as far as we can check without * actually mapping the pack file. */ - p = xmalloc(sizeof(*p) + path_len + 2); - strcpy(p->pack_name, path); - p->index_size = idx_size; p->pack_size = st.st_size; - p->index_base = idx_map; - p->next = NULL; - p->pack_base = NULL; - p->pack_last_used = 0; - p->pack_use_cnt = 0; p->pack_local = local; - if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1)) - memcpy(p->sha1, sha1, 20); + p->mtime = st.st_mtime; + if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1)) + hashclr(p->sha1); return p; } -struct packed_git *parse_pack_index(unsigned char *sha1) +struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path) { - char *path = sha1_pack_index_name(sha1); - return parse_pack_index_file(sha1, path); -} + const char *path = sha1_pack_name(sha1); + struct packed_git *p = alloc_packed_git(strlen(path) + 1); -struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path) -{ - struct packed_git *p; - unsigned long idx_size; - void *idx_map; - char *path; - - if (check_packed_git_idx(idx_path, &idx_size, &idx_map)) + strcpy(p->pack_name, path); + hashcpy(p->sha1, sha1); + if (check_packed_git_idx(idx_path, p)) { + free(p); return NULL; + } - path = sha1_pack_name(sha1); - - p = xmalloc(sizeof(*p) + strlen(path) + 2); - strcpy(p->pack_name, path); - p->index_size = idx_size; - p->pack_size = 0; - p->index_base = idx_map; - p->next = NULL; - p->pack_base = NULL; - p->pack_last_used = 0; - p->pack_use_cnt = 0; - memcpy(p->sha1, sha1, 20); return p; } void install_packed_git(struct packed_git *pack) { + if (pack->pack_fd != -1) + pack_open_fds++; + pack->next = packed_git; packed_git = pack; } static void prepare_packed_git_one(char *objdir, int local) { - char path[PATH_MAX]; + /* Ensure that this buffer is large enough so that we can + append "/pack/" without clobbering the stack even if + strlen(objdir) were PATH_MAX. */ + char path[PATH_MAX + 1 + 4 + 1 + 1]; int len; DIR *dir; struct dirent *de; @@ -573,26 +1010,91 @@ static void prepare_packed_git_one(char *objdir, int local) int namelen = strlen(de->d_name); struct packed_git *p; - if (strcmp(de->d_name + namelen - 4, ".idx")) + if (!has_extension(de->d_name, ".idx")) + continue; + + if (len + namelen + 1 > sizeof(path)) continue; - /* we have .idx. Is it a file we can map? */ + /* Don't reopen a pack we already have. */ strcpy(path + len, de->d_name); + for (p = packed_git; p; p = p->next) { + if (!memcmp(path, p->pack_name, len + namelen - 4)) + break; + } + if (p) + continue; + /* See if it really is a valid .idx file with corresponding + * .pack file that we can map. + */ p = add_packed_git(path, len + namelen, local); if (!p) continue; - p->next = packed_git; - packed_git = p; + install_packed_git(p); } closedir(dir); } +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_); + int st; + + /* + * Local packs tend to contain objects specific to our + * variant of the project than remote ones. In addition, + * remote ones could be on a network mounted filesystem. + * Favor local ones for these reasons. + */ + st = a->pack_local - b->pack_local; + if (st) + return -st; + + /* + * Younger packs tend to contain more recent objects, + * and more recent objects tend to get accessed more + * often. + */ + if (a->mtime < b->mtime) + return 1; + else if (a->mtime == b->mtime) + return 0; + return -1; +} + +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); + + /* 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]; + + free(ary); +} + +static int prepare_packed_git_run_once = 0; void prepare_packed_git(void) { - static int run_once = 0; struct alternate_object_database *alt; - if (run_once) + if (prepare_packed_git_run_once) return; prepare_packed_git_one(get_object_directory(), 1); prepare_alt_odb(); @@ -601,89 +1103,262 @@ void prepare_packed_git(void) prepare_packed_git_one(alt->base, 0); alt->name[-1] = '/'; } - run_once = 1; + rearrange_packed_git(); + prepare_packed_git_run_once = 1; +} + +void reprepare_packed_git(void) +{ + discard_revindex(); + prepare_packed_git_run_once = 0; + prepare_packed_git(); +} + +static void mark_bad_packed_object(struct packed_git *p, + const unsigned char *sha1) +{ + unsigned i; + for (i = 0; i < p->num_bad_objects; i++) + if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) + return; + p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1)); + hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1); + p->num_bad_objects++; +} + +static const struct packed_git *has_packed_and_bad(const unsigned char *sha1) +{ + struct packed_git *p; + unsigned i; + + for (p = packed_git; p; p = p->next) + for (i = 0; i < p->num_bad_objects; i++) + if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) + return p; + return NULL; } int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type) { - char header[100]; unsigned char real_sha1[20]; - SHA_CTX c; + hash_sha1_file(map, size, type, real_sha1); + return hashcmp(sha1, real_sha1) ? -1 : 0; +} - SHA1_Init(&c); - SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size)); - SHA1_Update(&c, map, size); - SHA1_Final(real_sha1, &c); - return memcmp(sha1, real_sha1, 20) ? -1 : 0; +static int git_open_noatime(const char *name) +{ + static int sha1_file_open_flag = O_NOATIME; + + for (;;) { + int fd = open(name, O_RDONLY | sha1_file_open_flag); + if (fd >= 0) + return fd; + + /* Might the failure be due to O_NOATIME? */ + if (errno != ENOENT && sha1_file_open_flag) { + sha1_file_open_flag = 0; + continue; + } + + return -1; + } } -static void *map_sha1_file_internal(const unsigned char *sha1, - unsigned long *size) +static int open_sha1_file(const unsigned char *sha1) { - struct stat st; - void *map; int fd; - char *filename = find_sha1_file(sha1, &st); + char *name = sha1_file_name(sha1); + struct alternate_object_database *alt; - if (!filename) { - return NULL; + fd = git_open_noatime(name); + if (fd >= 0) + return fd; + + prepare_alt_odb(); + errno = ENOENT; + for (alt = alt_odb_list; alt; alt = alt->next) { + name = alt->name; + fill_sha1_path(name, sha1); + fd = git_open_noatime(alt->base); + if (fd >= 0) + return fd; } + return -1; +} - fd = open(filename, O_RDONLY | sha1_file_open_flag); - if (fd < 0) { - /* See if it works without O_NOATIME */ - switch (sha1_file_open_flag) { - default: - fd = open(filename, O_RDONLY); - if (fd >= 0) - break; - /* Fallthrough */ - case 0: - return NULL; - } +void *map_sha1_file(const unsigned char *sha1, unsigned long *size) +{ + void *map; + int fd; - /* If it failed once, it will probably fail again. - * Stop using O_NOATIME - */ - sha1_file_open_flag = 0; + fd = open_sha1_file(sha1); + map = NULL; + if (fd >= 0) { + struct stat st; + + if (!fstat(fd, &st)) { + *size = xsize_t(st.st_size); + map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0); + } + close(fd); } - map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); - close(fd); - if (map == MAP_FAILED) - return NULL; - *size = st.st_size; return map; } -int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size) +/* + * There used to be a second loose object header format which + * was meant to mimic the in-pack format, allowing for direct + * copy of the object data. This format turned up not to be + * really worth it and we no longer write loose objects in that + * format. + */ +static int experimental_loose_object(unsigned char *map) { + unsigned int word; + + /* + * We must determine if the buffer contains the standard + * zlib-deflated stream or the experimental format based + * on the in-pack object format. Compare the header byte + * for each format: + * + * RFC1950 zlib w/ deflate : 0www1000 : 0 <= www <= 7 + * Experimental pack-based : Stttssss : ttt = 1,2,3,4 + * + * If bit 7 is clear and bits 0-3 equal 8, the buffer MUST be + * in standard loose-object format, UNLESS it is a Git-pack + * format object *exactly* 8 bytes in size when inflated. + * + * However, RFC1950 also specifies that the 1st 16-bit word + * must be divisible by 31 - this checksum tells us our buffer + * is in the standard format, giving a false positive only if + * the 1st word of the Git-pack format object happens to be + * divisible by 31, ie: + * ((byte0 * 256) + byte1) % 31 = 0 + * => 0ttt10000www1000 % 31 = 0 + * + * As it happens, this case can only arise for www=3 & ttt=1 + * - ie, a Commit object, which would have to be 8 bytes in + * size. As no Commit can be that small, we find that the + * combination of these two criteria (bitmask & checksum) + * can always correctly determine the buffer format. + */ + word = (map[0] << 8) + map[1]; + if ((map[0] & 0x8F) == 0x08 && !(word % 31)) + return 0; + else + return 1; +} + +unsigned long unpack_object_header_buffer(const unsigned char *buf, + unsigned long len, enum object_type *type, unsigned long *sizep) +{ + unsigned shift; + unsigned long size, c; + unsigned long used = 0; + + c = buf[used++]; + *type = (c >> 4) & 7; + size = c & 15; + shift = 4; + while (c & 0x80) { + if (len <= used || bitsizeof(long) <= shift) { + error("bad object header"); + return 0; + } + c = buf[used++]; + size += (c & 0x7f) << shift; + shift += 7; + } + *sizep = size; + return used; +} + +int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz) +{ + unsigned long size, used; + static const char valid_loose_object_type[8] = { + 0, /* OBJ_EXT */ + 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */ + 0, /* "delta" and others are invalid in a loose object */ + }; + enum object_type type; + /* Get the data stream */ memset(stream, 0, sizeof(*stream)); stream->next_in = map; stream->avail_in = mapsize; stream->next_out = buffer; - stream->avail_out = size; + stream->avail_out = bufsiz; + + if (experimental_loose_object(map)) { + /* + * The old experimental format we no longer produce; + * we can still read it. + */ + used = unpack_object_header_buffer(map, mapsize, &type, &size); + if (!used || !valid_loose_object_type[type]) + return -1; + map += used; + mapsize -= used; - inflateInit(stream); - return inflate(stream, 0); + /* Set up the stream for the rest.. */ + stream->next_in = map; + stream->avail_in = mapsize; + git_inflate_init(stream); + + /* And generate the fake traditional header */ + stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu", + typename(type), size); + return 0; + } + git_inflate_init(stream); + return git_inflate(stream, 0); } -static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size) +static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1) { int bytes = strlen(buffer) + 1; - unsigned char *buf = xmalloc(1+size); - - memcpy(buf, buffer + bytes, stream->total_out - bytes); - bytes = stream->total_out - bytes; - if (bytes < size) { + unsigned char *buf = xmallocz(size); + unsigned long n; + int status = Z_OK; + + n = stream->total_out - bytes; + if (n > size) + n = size; + memcpy(buf, (char *) buffer + bytes, n); + bytes = n; + if (bytes <= size) { + /* + * The above condition must be (bytes <= size), not + * (bytes < size). In other words, even though we + * expect no more output and set avail_out to zero, + * the input zlib stream may have bytes that express + * "this concludes the stream", and we *do* want to + * eat that input. + * + * Otherwise we would not be able to test that we + * consumed all the input to reach the expected size; + * we also want to check that zlib tells us that all + * went well with status == Z_STREAM_END at the end. + */ stream->next_out = buf + bytes; stream->avail_out = size - bytes; - while (inflate(stream, Z_FINISH) == Z_OK) - /* nothing */; + while (status == Z_OK) + status = git_inflate(stream, Z_FINISH); } - buf[size] = 0; - inflateEnd(stream); - return buf; + if (status == Z_STREAM_END && !stream->avail_in) { + git_inflate_end(stream); + return buf; + } + + if (status < 0) + error("corrupt loose object '%s'", sha1_to_hex(sha1)); + else if (stream->avail_in) + error("garbage at end of loose object '%s'", + sha1_to_hex(sha1)); + free(buf); + return NULL; } /* @@ -691,26 +1366,27 @@ static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size * too permissive for what we want to check. So do an anal * object header parse by hand. */ -int parse_sha1_header(char *hdr, char *type, unsigned long *sizep) +int parse_sha1_header(const char *hdr, unsigned long *sizep) { + char type[10]; int i; unsigned long size; /* - * The type can be at most ten bytes (including the + * The type can be at most ten bytes (including the * terminating '\0' that we add), and is followed by - * a space. + * a space. */ - i = 10; + i = 0; for (;;) { char c = *hdr++; if (c == ' ') break; - if (!--i) + type[i++] = c; + if (i >= sizeof(type)) return -1; - *type++ = c; } - *type = 0; + type[i] = 0; /* * The length must follow immediately, and be in canonical @@ -733,394 +1409,573 @@ int parse_sha1_header(char *hdr, char *type, unsigned long *sizep) /* * The length must be followed by a zero byte */ - return *hdr ? -1 : 0; + return *hdr ? -1 : type_from_string(type); } -void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size) +static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1) { int ret; - z_stream stream; + git_zstream stream; char hdr[8192]; ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)); - if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0) + if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0) return NULL; - return unpack_sha1_rest(&stream, hdr, *size); + return unpack_sha1_rest(&stream, hdr, *size, sha1); } -/* forward declaration for a mutually recursive function */ -static int packed_object_info(struct pack_entry *entry, - char *type, unsigned long *sizep); - -static int packed_delta_info(unsigned char *base_sha1, - unsigned long delta_size, - unsigned long left, - char *type, - unsigned long *sizep, - struct packed_git *p) +unsigned long get_size_from_delta(struct packed_git *p, + struct pack_window **w_curs, + off_t curpos) { - struct pack_entry base_ent; + const unsigned char *data; + unsigned char delta_head[20], *in; + git_zstream stream; + int st; - if (left < 20) - die("truncated pack file"); + memset(&stream, 0, sizeof(stream)); + stream.next_out = delta_head; + stream.avail_out = sizeof(delta_head); - /* The base entry _must_ be in the same pack */ - if (!find_pack_entry_one(base_sha1, &base_ent, p)) - die("failed to find delta-pack base object %s", - sha1_to_hex(base_sha1)); + git_inflate_init(&stream); + do { + in = use_pack(p, w_curs, curpos, &stream.avail_in); + stream.next_in = in; + st = git_inflate(&stream, Z_FINISH); + curpos += stream.next_in - in; + } while ((st == Z_OK || st == Z_BUF_ERROR) && + stream.total_out < sizeof(delta_head)); + git_inflate_end(&stream); + if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) { + error("delta data unpack-initial failed"); + return 0; + } - /* We choose to only get the type of the base object and - * ignore potentially corrupt pack file that expects the delta - * based on a base with a wrong size. This saves tons of - * inflate() calls. + /* Examine the initial part of the delta to figure out + * the result size. */ + data = delta_head; - if (packed_object_info(&base_ent, type, NULL)) - die("cannot get info for delta-pack base"); + /* ignore base size */ + get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); - if (sizep) { - const unsigned char *data; - unsigned char delta_head[64]; - unsigned long result_size; - z_stream stream; - int st; - - memset(&stream, 0, sizeof(stream)); - - data = stream.next_in = base_sha1 + 20; - stream.avail_in = left - 20; - stream.next_out = delta_head; - stream.avail_out = sizeof(delta_head); - - inflateInit(&stream); - st = inflate(&stream, Z_FINISH); - inflateEnd(&stream); - if ((st != Z_STREAM_END) && - stream.total_out != sizeof(delta_head)) - die("delta data unpack-initial failed"); - - /* Examine the initial part of the delta to figure out - * the result size. - */ - data = delta_head; - get_delta_hdr_size(&data); /* ignore base size */ - - /* Read the result size */ - result_size = get_delta_hdr_size(&data); - *sizep = result_size; - } - return 0; + /* Read the result size */ + return get_delta_hdr_size(&data, delta_head+sizeof(delta_head)); } -static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset, - enum object_type *type, unsigned long *sizep) +static off_t get_delta_base(struct packed_git *p, + struct pack_window **w_curs, + off_t *curpos, + enum object_type type, + off_t delta_obj_offset) { - unsigned shift; - unsigned char *pack, c; - unsigned long size; + unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL); + off_t base_offset; + + /* use_pack() assured us we have [base_info, base_info + 20) + * as a range that we can look at without walking off the + * end of the mapped window. Its actually the hash size + * that is assured. An OFS_DELTA longer than the hash size + * is stupid, as then a REF_DELTA would be smaller to store. + */ + if (type == OBJ_OFS_DELTA) { + unsigned used = 0; + unsigned char c = base_info[used++]; + base_offset = c & 127; + while (c & 128) { + base_offset += 1; + if (!base_offset || MSB(base_offset, 7)) + return 0; /* overflow */ + c = base_info[used++]; + base_offset = (base_offset << 7) + (c & 127); + } + base_offset = delta_obj_offset - base_offset; + if (base_offset <= 0 || base_offset >= delta_obj_offset) + return 0; /* out of bound */ + *curpos += used; + } else if (type == OBJ_REF_DELTA) { + /* The base entry _must_ be in the same pack */ + base_offset = find_pack_entry_one(base_info, p); + *curpos += 20; + } else + die("I am totally screwed"); + return base_offset; +} - if (offset >= p->pack_size) - die("object offset outside of pack file"); +/* forward declaration for a mutually recursive function */ +static int packed_object_info(struct packed_git *p, off_t offset, + unsigned long *sizep, int *rtype); + +static int packed_delta_info(struct packed_git *p, + struct pack_window **w_curs, + off_t curpos, + enum object_type type, + off_t obj_offset, + unsigned long *sizep) +{ + off_t base_offset; + + base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset); + if (!base_offset) + return OBJ_BAD; + type = packed_object_info(p, base_offset, NULL, NULL); + if (type <= OBJ_NONE) { + struct revindex_entry *revidx; + const unsigned char *base_sha1; + revidx = find_pack_revindex(p, base_offset); + if (!revidx) + return OBJ_BAD; + base_sha1 = nth_packed_object_sha1(p, revidx->nr); + mark_bad_packed_object(p, base_sha1); + type = sha1_object_info(base_sha1, NULL); + if (type <= OBJ_NONE) + return OBJ_BAD; + } - pack = p->pack_base + offset; - c = *pack++; - offset++; - *type = (c >> 4) & 7; - size = c & 15; - shift = 4; - while (c & 0x80) { - if (offset >= p->pack_size) - die("object offset outside of pack file"); - c = *pack++; - offset++; - size += (c & 0x7f) << shift; - shift += 7; + /* We choose to only get the type of the base object and + * ignore potentially corrupt pack file that expects the delta + * based on a base with a wrong size. This saves tons of + * inflate() calls. + */ + if (sizep) { + *sizep = get_size_from_delta(p, w_curs, curpos); + if (*sizep == 0) + type = OBJ_BAD; } - *sizep = size; - return offset; + + return type; } -int check_reuse_pack_delta(struct packed_git *p, unsigned long offset, - unsigned char *base, unsigned long *sizep, - enum object_type *kindp) +int unpack_object_header(struct packed_git *p, + struct pack_window **w_curs, + off_t *curpos, + unsigned long *sizep) { - unsigned long ptr; - int status = -1; - - use_packed_git(p); - ptr = offset; - ptr = unpack_object_header(p, ptr, kindp, sizep); - if (*kindp != OBJ_DELTA) - goto done; - memcpy(base, p->pack_base + ptr, 20); - status = 0; - done: - unuse_packed_git(p); - return status; + unsigned char *base; + unsigned long left; + unsigned long used; + enum object_type type; + + /* use_pack() assures us we have [base, base + 20) available + * as a range that we can look at. (Its actually the hash + * size that is assured.) With our object header encoding + * the maximum deflated object size is 2^137, which is just + * insane, so we know won't exceed what we have been given. + */ + base = use_pack(p, w_curs, *curpos, &left); + used = unpack_object_header_buffer(base, left, &type, sizep); + if (!used) { + type = OBJ_BAD; + } else + *curpos += used; + + return type; } -void packed_object_info_detail(struct pack_entry *e, - char *type, - unsigned long *size, - unsigned long *store_size, - unsigned int *delta_chain_length, - unsigned char *base_sha1) -{ - struct packed_git *p = e->p; - unsigned long offset, left; - unsigned char *pack; - enum object_type kind; - - offset = unpack_object_header(p, e->offset, &kind, size); - pack = p->pack_base + offset; - left = p->pack_size - offset; - if (kind != OBJ_DELTA) - *delta_chain_length = 0; - else { - unsigned int chain_length = 0; - memcpy(base_sha1, pack, 20); - do { - struct pack_entry base_ent; - unsigned long junk; - - find_pack_entry_one(pack, &base_ent, p); - offset = unpack_object_header(p, base_ent.offset, - &kind, &junk); - pack = p->pack_base + offset; - chain_length++; - } while (kind == OBJ_DELTA); - *delta_chain_length = chain_length; - } - switch (kind) { - case OBJ_COMMIT: - strcpy(type, "commit"); +static int packed_object_info(struct packed_git *p, off_t obj_offset, + unsigned long *sizep, int *rtype) +{ + struct pack_window *w_curs = NULL; + unsigned long size; + off_t curpos = obj_offset; + enum object_type type; + + type = unpack_object_header(p, &w_curs, &curpos, &size); + if (rtype) + *rtype = type; /* representation type */ + + switch (type) { + case OBJ_OFS_DELTA: + case OBJ_REF_DELTA: + type = packed_delta_info(p, &w_curs, curpos, + type, obj_offset, sizep); break; + case OBJ_COMMIT: case OBJ_TREE: - strcpy(type, "tree"); - break; case OBJ_BLOB: - strcpy(type, "blob"); - break; case OBJ_TAG: - strcpy(type, "tag"); + if (sizep) + *sizep = size; break; default: - die("corrupted pack file %s containing object of kind %d", - p->pack_name, kind); + error("unknown object type %i at offset %"PRIuMAX" in %s", + type, (uintmax_t)obj_offset, p->pack_name); + type = OBJ_BAD; } - *store_size = 0; /* notyet */ + unuse_pack(&w_curs); + return type; } -static int packed_object_info(struct pack_entry *entry, - char *type, unsigned long *sizep) +static void *unpack_compressed_entry(struct packed_git *p, + struct pack_window **w_curs, + off_t curpos, + unsigned long size) { - struct packed_git *p = entry->p; - unsigned long offset, size, left; - unsigned char *pack; - enum object_type kind; - int retval; + int st; + git_zstream stream; + unsigned char *buffer, *in; - if (use_packed_git(p)) - die("cannot map packed file"); + buffer = xmallocz(size); + memset(&stream, 0, sizeof(stream)); + stream.next_out = buffer; + stream.avail_out = size + 1; - offset = unpack_object_header(p, entry->offset, &kind, &size); - pack = p->pack_base + offset; - left = p->pack_size - offset; + git_inflate_init(&stream); + do { + in = use_pack(p, w_curs, curpos, &stream.avail_in); + stream.next_in = in; + st = git_inflate(&stream, Z_FINISH); + if (!stream.avail_out) + break; /* the payload is larger than it should be */ + curpos += stream.next_in - in; + } while (st == Z_OK || st == Z_BUF_ERROR); + git_inflate_end(&stream); + if ((st != Z_STREAM_END) || stream.total_out != size) { + free(buffer); + return NULL; + } - switch (kind) { - case OBJ_DELTA: - retval = packed_delta_info(pack, size, left, type, sizep, p); - unuse_packed_git(p); - return retval; - case OBJ_COMMIT: - strcpy(type, "commit"); - break; - case OBJ_TREE: - strcpy(type, "tree"); - break; - case OBJ_BLOB: - strcpy(type, "blob"); - break; - case OBJ_TAG: - strcpy(type, "tag"); - break; - default: - die("corrupted pack file %s containing object of kind %d", - p->pack_name, kind); + return buffer; +} + +#define MAX_DELTA_CACHE (256) + +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 struct delta_base_cache_entry { + struct delta_base_cache_lru_list lru; + void *data; + struct packed_git *p; + off_t base_offset; + 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) +{ + unsigned long hash; + + hash = (unsigned long)p + (unsigned long)base_offset; + hash += (hash >> 8) + (hash >> 16); + return hash % MAX_DELTA_CACHE; +} + +static int in_delta_base_cache(struct packed_git *p, off_t base_offset) +{ + unsigned long hash = pack_entry_hash(p, base_offset); + struct delta_base_cache_entry *ent = delta_base_cache + hash; + return (ent->data && ent->p == p && ent->base_offset == base_offset); +} + +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) +{ + void *ret; + unsigned long hash = pack_entry_hash(p, base_offset); + struct delta_base_cache_entry *ent = delta_base_cache + hash; + + ret = ent->data; + if (!ret || ent->p != p || ent->base_offset != base_offset) + return unpack_entry(p, base_offset, type, base_size); + + if (!keep_cache) { + ent->data = NULL; + ent->lru.next->prev = ent->lru.prev; + ent->lru.prev->next = ent->lru.next; + delta_base_cached -= ent->size; + } else { + ret = xmemdupz(ent->data, ent->size); } - if (sizep) - *sizep = size; - unuse_packed_git(p); - return 0; + *type = ent->type; + *base_size = ent->size; + return ret; } -/* forward declaration for a mutually recursive function */ -static void *unpack_entry(struct pack_entry *, char *, unsigned long *); +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; + } +} -static void *unpack_delta_entry(unsigned char *base_sha1, - unsigned long delta_size, - unsigned long left, - char *type, - unsigned long *sizep, - struct packed_git *p) -{ - struct pack_entry base_ent; - void *data, *delta_data, *result, *base; - unsigned long data_size, result_size, base_size; - z_stream stream; - int st; +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]); +} - if (left < 20) - die("truncated pack file"); - data = base_sha1 + 20; - data_size = left - 20; - delta_data = xmalloc(delta_size); +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; + + 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; + release_delta_base_cache(f); + } - memset(&stream, 0, sizeof(stream)); + ent->p = p; + ent->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; +} + +static void *read_object(const unsigned char *sha1, enum object_type *type, + unsigned long *size); + +static void *unpack_delta_entry(struct packed_git *p, + struct pack_window **w_curs, + off_t curpos, + unsigned long delta_size, + off_t obj_offset, + enum object_type *type, + unsigned long *sizep) +{ + void *delta_data, *result, *base; + unsigned long base_size; + off_t base_offset; + + base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset); + if (!base_offset) { + error("failed to validate delta base reference " + "at offset %"PRIuMAX" from %s", + (uintmax_t)curpos, p->pack_name); + return NULL; + } + unuse_pack(w_curs); + base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0); + if (!base) { + /* + * We're probably in deep shit, but let's try to fetch + * the required base anyway from another pack or loose. + * This is costly but should happen only in the presence + * of a corrupted pack, and is better than failing outright. + */ + struct revindex_entry *revidx; + const unsigned char *base_sha1; + revidx = find_pack_revindex(p, base_offset); + if (!revidx) + return NULL; + base_sha1 = nth_packed_object_sha1(p, revidx->nr); + error("failed to read delta base object %s" + " at offset %"PRIuMAX" from %s", + sha1_to_hex(base_sha1), (uintmax_t)base_offset, + p->pack_name); + mark_bad_packed_object(p, base_sha1); + base = read_object(base_sha1, type, &base_size); + if (!base) + return NULL; + } - stream.next_in = data; - stream.avail_in = data_size; - stream.next_out = delta_data; - stream.avail_out = delta_size; - - inflateInit(&stream); - st = inflate(&stream, Z_FINISH); - inflateEnd(&stream); - if ((st != Z_STREAM_END) || stream.total_out != delta_size) - die("delta data unpack failed"); - - /* The base entry _must_ be in the same pack */ - if (!find_pack_entry_one(base_sha1, &base_ent, p)) - die("failed to find delta-pack base object %s", - sha1_to_hex(base_sha1)); - base = unpack_entry_gently(&base_ent, type, &base_size); - if (!base) - die("failed to read delta-pack base object %s", - sha1_to_hex(base_sha1)); + delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size); + if (!delta_data) { + error("failed to unpack compressed delta " + "at offset %"PRIuMAX" from %s", + (uintmax_t)curpos, p->pack_name); + free(base); + return NULL; + } result = patch_delta(base, base_size, delta_data, delta_size, - &result_size); + sizep); if (!result) die("failed to apply delta"); free(delta_data); - free(base); - *sizep = result_size; + add_delta_base_cache(p, base_offset, base, base_size, *type); return result; } -static void *unpack_non_delta_entry(unsigned char *data, - unsigned long size, - unsigned long left) +static void write_pack_access_log(struct packed_git *p, off_t obj_offset) { - int st; - z_stream stream; - unsigned char *buffer; - - buffer = xmalloc(size + 1); - buffer[size] = 0; - memset(&stream, 0, sizeof(stream)); - stream.next_in = data; - stream.avail_in = left; - stream.next_out = buffer; - stream.avail_out = size; - - inflateInit(&stream); - st = inflate(&stream, Z_FINISH); - inflateEnd(&stream); - if ((st != Z_STREAM_END) || stream.total_out != size) { - free(buffer); - return NULL; + static FILE *log_file; + + if (!log_file) { + log_file = fopen(log_pack_access, "w"); + if (!log_file) { + error("cannot open pack access log '%s' for writing: %s", + log_pack_access, strerror(errno)); + log_pack_access = NULL; + return; + } } - - return buffer; + fprintf(log_file, "%s %"PRIuMAX"\n", + p->pack_name, (uintmax_t)obj_offset); + fflush(log_file); } -static void *unpack_entry(struct pack_entry *entry, - char *type, unsigned long *sizep) -{ - struct packed_git *p = entry->p; - void *retval; +int do_check_packed_object_crc; - if (use_packed_git(p)) - die("cannot map packed file"); - retval = unpack_entry_gently(entry, type, sizep); - unuse_packed_git(p); - if (!retval) - die("corrupted pack file %s", p->pack_name); - return retval; -} - -/* The caller is responsible for use_packed_git()/unuse_packed_git() pair */ -void *unpack_entry_gently(struct pack_entry *entry, - char *type, unsigned long *sizep) +void *unpack_entry(struct packed_git *p, off_t obj_offset, + enum object_type *type, unsigned long *sizep) { - struct packed_git *p = entry->p; - unsigned long offset, size, left; - unsigned char *pack; - enum object_type kind; - void *retval; + struct pack_window *w_curs = NULL; + off_t curpos = obj_offset; + void *data; + + if (log_pack_access) + write_pack_access_log(p, obj_offset); + + 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; + if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) { + const unsigned char *sha1 = + nth_packed_object_sha1(p, revidx->nr); + error("bad packed object CRC for %s", + sha1_to_hex(sha1)); + mark_bad_packed_object(p, sha1); + unuse_pack(&w_curs); + return NULL; + } + } - offset = unpack_object_header(p, entry->offset, &kind, &size); - pack = p->pack_base + offset; - left = p->pack_size - offset; - switch (kind) { - case OBJ_DELTA: - retval = unpack_delta_entry(pack, size, left, type, sizep, p); - return retval; - case OBJ_COMMIT: - strcpy(type, "commit"); + *type = unpack_object_header(p, &w_curs, &curpos, sizep); + switch (*type) { + case OBJ_OFS_DELTA: + case OBJ_REF_DELTA: + data = unpack_delta_entry(p, &w_curs, curpos, *sizep, + obj_offset, type, sizep); break; + case OBJ_COMMIT: case OBJ_TREE: - strcpy(type, "tree"); - break; case OBJ_BLOB: - strcpy(type, "blob"); - break; case OBJ_TAG: - strcpy(type, "tag"); + data = unpack_compressed_entry(p, &w_curs, curpos, *sizep); break; default: - return NULL; + data = NULL; + error("unknown object type %i at offset %"PRIuMAX" in %s", + *type, (uintmax_t)obj_offset, p->pack_name); } - *sizep = size; - retval = unpack_non_delta_entry(pack, size, left); - return retval; + unuse_pack(&w_curs); + return data; } -int num_packed_objects(const struct packed_git *p) +const unsigned char *nth_packed_object_sha1(struct packed_git *p, + uint32_t n) { - /* See check_packed_git_idx() */ - return (p->index_size - 20 - 20 - 4*256) / 24; + const unsigned char *index = p->index_data; + if (!index) { + if (open_pack_index(p)) + return NULL; + index = p->index_data; + } + if (n >= p->num_objects) + return NULL; + index += 4 * 256; + if (p->index_version == 1) { + return index + 24 * n + 4; + } else { + index += 8; + return index + 20 * n; + } } -int nth_packed_object_sha1(const struct packed_git *p, int n, - unsigned char* sha1) +off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n) { - void *index = p->index_base + 256; - if (n < 0 || num_packed_objects(p) <= n) - return -1; - memcpy(sha1, (index + 24 * n + 4), 20); - return 0; + const unsigned char *index = p->index_data; + index += 4 * 256; + if (p->index_version == 1) { + return ntohl(*((uint32_t *)(index + 24 * n))); + } else { + uint32_t off; + index += 8 + p->num_objects * (20 + 4); + off = ntohl(*((uint32_t *)(index + 4 * n))); + if (!(off & 0x80000000)) + return off; + index += p->num_objects * 4 + (off & 0x7fffffff) * 8; + return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) | + ntohl(*((uint32_t *)(index + 4))); + } } -int find_pack_entry_one(const unsigned char *sha1, - struct pack_entry *e, struct packed_git *p) +off_t find_pack_entry_one(const unsigned char *sha1, + struct packed_git *p) { - unsigned int *level1_ofs = p->index_base; - int hi = ntohl(level1_ofs[*sha1]); - int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1])); - void *index = p->index_base + 256; + const uint32_t *level1_ofs = p->index_data; + const unsigned char *index = p->index_data; + unsigned hi, lo, stride; + static int use_lookup = -1; + static int debug_lookup = -1; + + if (debug_lookup < 0) + debug_lookup = !!getenv("GIT_DEBUG_LOOKUP"); + + if (!index) { + if (open_pack_index(p)) + return 0; + level1_ofs = p->index_data; + index = p->index_data; + } + if (p->index_version > 1) { + level1_ofs += 2; + index += 8; + } + index += 4 * 256; + hi = ntohl(level1_ofs[*sha1]); + lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1])); + if (p->index_version > 1) { + stride = 20; + } else { + stride = 24; + index += 4; + } + + if (debug_lookup) + printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n", + sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects); + + if (use_lookup < 0) + use_lookup = !!getenv("GIT_USE_LOOKUP"); + if (use_lookup) { + int pos = sha1_entry_pos(index, stride, 0, + lo, hi, p->num_objects, sha1); + if (pos < 0) + return 0; + return nth_packed_object_offset(p, pos); + } do { - int mi = (lo + hi) / 2; - int cmp = memcmp(index + 24 * mi + 4, sha1, 20); - if (!cmp) { - e->offset = ntohl(*((int*)(index + 24 * mi))); - memcpy(e->sha1, sha1, 20); - e->p = p; - return 1; - } + unsigned mi = (lo + hi) / 2; + int cmp = hashcmp(index + mi * stride, sha1); + + if (debug_lookup) + printf("lo %u hi %u rg %u mi %u\n", + lo, hi, hi - lo, mi); + if (!cmp) + return nth_packed_object_offset(p, mi); if (cmp > 0) hi = mi; else @@ -1129,119 +1984,313 @@ int find_pack_entry_one(const unsigned char *sha1, return 0; } +static int is_pack_valid(struct packed_git *p) +{ + /* An already open pack is known to be valid. */ + if (p->pack_fd != -1) + return 1; + + /* If the pack has one window completely covering the + * file size, the pack is known to be valid even if + * the descriptor is not currently open. + */ + if (p->windows) { + struct pack_window *w = p->windows; + + if (!w->offset && w->len == p->pack_size) + return 1; + } + + /* Force the pack to open to prove its valid. */ + return !open_packed_git(p); +} + static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e) { + static struct packed_git *last_found = (void *)1; struct packed_git *p; + off_t offset; + prepare_packed_git(); + if (!packed_git) + return 0; + p = (last_found == (void *)1) ? packed_git : last_found; - for (p = packed_git; p; p = p->next) { - if (find_pack_entry_one(sha1, e, p)) + do { + if (p->num_bad_objects) { + unsigned i; + for (i = 0; i < p->num_bad_objects; i++) + if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i)) + goto next; + } + + offset = find_pack_entry_one(sha1, p); + if (offset) { + /* + * We are about to tell the caller where they can + * locate the requested object. We better make + * sure the packfile is still here and can be + * accessed before supplying that answer, as + * it may have been deleted since the index + * was loaded! + */ + if (!is_pack_valid(p)) { + error("packfile %s cannot be accessed", p->pack_name); + goto next; + } + e->offset = offset; + e->p = p; + hashcpy(e->sha1, sha1); + last_found = p; return 1; - } + } + + next: + if (p == last_found) + p = packed_git; + else + p = p->next; + if (p == last_found) + p = p->next; + } while (p); return 0; } -struct packed_git *find_sha1_pack(const unsigned char *sha1, +struct packed_git *find_sha1_pack(const unsigned char *sha1, struct packed_git *packs) { struct packed_git *p; - struct pack_entry e; for (p = packs; p; p = p->next) { - if (find_pack_entry_one(sha1, &e, p)) + if (find_pack_entry_one(sha1, p)) return p; } return NULL; - + } -int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep) +static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep) { int status; unsigned long mapsize, size; void *map; - z_stream stream; - char hdr[128]; + git_zstream stream; + char hdr[32]; - map = map_sha1_file_internal(sha1, &mapsize); - if (!map) { - struct pack_entry e; - - if (!find_pack_entry(sha1, &e)) - return error("unable to find %s", sha1_to_hex(sha1)); - return packed_object_info(&e, type, sizep); - } + map = map_sha1_file(sha1, &mapsize); + if (!map) + return error("unable to find %s", sha1_to_hex(sha1)); if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) status = error("unable to unpack %s header", sha1_to_hex(sha1)); - if (parse_sha1_header(hdr, type, &size) < 0) + else if ((status = parse_sha1_header(hdr, &size)) < 0) status = error("unable to parse %s header", sha1_to_hex(sha1)); - else { - status = 0; - if (sizep) - *sizep = size; - } - inflateEnd(&stream); + else if (sizep) + *sizep = size; + git_inflate_end(&stream); munmap(map, mapsize); return status; } -static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size) +/* returns enum object_type or negative */ +int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi) { + struct cached_object *co; struct pack_entry e; + int status, rtype; + + co = find_cached_object(sha1); + if (co) { + if (oi->sizep) + *(oi->sizep) = co->size; + oi->whence = OI_CACHED; + return co->type; + } if (!find_pack_entry(sha1, &e)) { - error("cannot read sha1_file for %s", sha1_to_hex(sha1)); + /* Most likely it's a loose object. */ + status = sha1_loose_object_info(sha1, oi->sizep); + if (status >= 0) { + oi->whence = OI_LOOSE; + return status; + } + + /* Not a loose object; someone else may have just packed it. */ + reprepare_packed_git(); + if (!find_pack_entry(sha1, &e)) + return status; + } + + status = packed_object_info(e.p, e.offset, oi->sizep, &rtype); + if (status < 0) { + mark_bad_packed_object(e.p, sha1); + status = sha1_object_info_extended(sha1, oi); + } else if (in_delta_base_cache(e.p, e.offset)) { + oi->whence = OI_DBCACHED; + } else { + oi->whence = OI_PACKED; + oi->u.packed.offset = e.offset; + oi->u.packed.pack = e.p; + oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA || + rtype == OBJ_OFS_DELTA); + } + + return status; +} + +int sha1_object_info(const unsigned char *sha1, unsigned long *sizep) +{ + struct object_info oi; + + oi.sizep = sizep; + return sha1_object_info_extended(sha1, &oi); +} + +static void *read_packed_sha1(const unsigned char *sha1, + enum object_type *type, unsigned long *size) +{ + struct pack_entry e; + void *data; + + if (!find_pack_entry(sha1, &e)) return NULL; + data = cache_or_unpack_entry(e.p, e.offset, size, type, 1); + if (!data) { + /* + * We're probably in deep shit, but let's try to fetch + * the required object anyway from another pack or loose. + * This should happen only in the presence of a corrupted + * pack, and is better than failing outright. + */ + error("failed to read object %s at offset %"PRIuMAX" from %s", + sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name); + mark_bad_packed_object(e.p, sha1); + data = read_object(sha1, type, size); + } + return data; +} + +int pretend_sha1_file(void *buf, unsigned long len, enum object_type type, + unsigned char *sha1) +{ + struct cached_object *co; + + hash_sha1_file(buf, len, typename(type), sha1); + if (has_sha1_file(sha1) || find_cached_object(sha1)) + return 0; + if (cached_object_alloc <= cached_object_nr) { + cached_object_alloc = alloc_nr(cached_object_alloc); + cached_objects = xrealloc(cached_objects, + sizeof(*cached_objects) * + cached_object_alloc); } - return unpack_entry(&e, type, size); + co = &cached_objects[cached_object_nr++]; + co->size = len; + co->type = type; + co->buf = xmalloc(len); + memcpy(co->buf, buf, len); + hashcpy(co->sha1, sha1); + return 0; } -void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size) +static void *read_object(const unsigned char *sha1, enum object_type *type, + unsigned long *size) { unsigned long mapsize; void *map, *buf; - struct pack_entry e; + struct cached_object *co; - if (find_pack_entry(sha1, &e)) - return read_packed_sha1(sha1, type, size); - map = map_sha1_file_internal(sha1, &mapsize); + co = find_cached_object(sha1); + if (co) { + *type = co->type; + *size = co->size; + return xmemdupz(co->buf, co->size); + } + + buf = read_packed_sha1(sha1, type, size); + if (buf) + return buf; + map = map_sha1_file(sha1, &mapsize); if (map) { - buf = unpack_sha1_file(map, mapsize, type, size); + buf = unpack_sha1_file(map, mapsize, type, size, sha1); munmap(map, mapsize); return buf; } + reprepare_packed_git(); + return read_packed_sha1(sha1, type, size); +} + +/* + * This function dies on corrupt objects; the callers who want to + * deal with them should arrange to call read_object() and give error + * messages themselves. + */ +void *read_sha1_file_extended(const unsigned char *sha1, + enum object_type *type, + unsigned long *size, + unsigned flag) +{ + void *data; + char *path; + const struct packed_git *p; + const unsigned char *repl = (flag & READ_SHA1_FILE_REPLACE) + ? lookup_replace_object(sha1) : sha1; + + errno = 0; + data = read_object(repl, type, size); + if (data) + return data; + + if (errno && errno != ENOENT) + die_errno("failed to read object %s", sha1_to_hex(sha1)); + + /* die if we replaced an object with one that does not exist */ + if (repl != sha1) + die("replacement %s not found for %s", + sha1_to_hex(repl), sha1_to_hex(sha1)); + + if (has_loose_object(repl)) { + path = sha1_file_name(sha1); + die("loose object %s (stored in %s) is corrupt", + sha1_to_hex(repl), path); + } + + if ((p = has_packed_and_bad(repl)) != NULL) + die("packed object %s (stored in %s) is corrupt", + sha1_to_hex(repl), p->pack_name); + return NULL; } void *read_object_with_reference(const unsigned char *sha1, - const char *required_type, + const char *required_type_name, unsigned long *size, unsigned char *actual_sha1_return) { - char type[20]; + enum object_type type, required_type; void *buffer; unsigned long isize; unsigned char actual_sha1[20]; - memcpy(actual_sha1, sha1, 20); + required_type = type_from_string(required_type_name); + hashcpy(actual_sha1, sha1); while (1) { int ref_length = -1; const char *ref_type = NULL; - buffer = read_sha1_file(actual_sha1, type, &isize); + buffer = read_sha1_file(actual_sha1, &type, &isize); if (!buffer) return NULL; - if (!strcmp(type, required_type)) { + if (type == required_type) { *size = isize; if (actual_sha1_return) - memcpy(actual_sha1_return, actual_sha1, 20); + hashcpy(actual_sha1_return, actual_sha1); return buffer; } /* Handle references */ - else if (!strcmp(type, "commit")) + else if (type == OBJ_COMMIT) ref_type = "tree "; - else if (!strcmp(type, "tag")) + else if (type == OBJ_TAG) ref_type = "object "; else { free(buffer); @@ -1249,8 +2298,9 @@ void *read_object_with_reference(const unsigned char *sha1, } ref_length = strlen(ref_type); - if (memcmp(buffer, ref_type, ref_length) || - get_sha1_hex(buffer + ref_length, actual_sha1)) { + if (ref_length + 40 > isize || + memcmp(buffer, ref_type, ref_length) || + get_sha1_hex((char *) buffer + ref_length, actual_sha1)) { free(buffer); return NULL; } @@ -1260,71 +2310,36 @@ void *read_object_with_reference(const unsigned char *sha1, } } -char *write_sha1_file_prepare(void *buf, - unsigned long len, - const char *type, - unsigned char *sha1, - unsigned char *hdr, - int *hdrlen) +static void write_sha1_file_prepare(const void *buf, unsigned long len, + const char *type, unsigned char *sha1, + char *hdr, int *hdrlen) { - SHA_CTX c; + git_SHA_CTX c; /* Generate the header */ - *hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1; + *hdrlen = sprintf(hdr, "%s %lu", type, len)+1; /* Sha1.. */ - SHA1_Init(&c); - SHA1_Update(&c, hdr, *hdrlen); - SHA1_Update(&c, buf, len); - SHA1_Final(sha1, &c); - - return sha1_file_name(sha1); + git_SHA1_Init(&c); + git_SHA1_Update(&c, hdr, *hdrlen); + git_SHA1_Update(&c, buf, len); + git_SHA1_Final(sha1, &c); } /* - * Link the tempfile to the final place, possibly creating the - * last directory level as you do so. - * - * Returns the errno on failure, 0 on success. + * Move the just written object into its final resting place. + * NEEDSWORK: this should be renamed to finalize_temp_file() as + * "moving" is only a part of what it does, when no patch between + * master to pu changes the call sites of this function. */ -static int link_temp_to_file(const char *tmpfile, char *filename) +int move_temp_to_file(const char *tmpfile, const char *filename) { - int ret; + int ret = 0; - if (!link(tmpfile, filename)) - return 0; - - /* - * Try to mkdir the last path component if that failed - * with an ENOENT. - * - * Re-try the "link()" regardless of whether the mkdir - * succeeds, since a race might mean that somebody - * else succeeded. - */ - ret = errno; - if (ret == ENOENT) { - char *dir = strrchr(filename, '/'); - if (dir) { - *dir = 0; - mkdir(filename, 0777); - if (adjust_shared_perm(filename)) - return -2; - *dir = '/'; - if (!link(tmpfile, filename)) - return 0; - ret = errno; - } - } - return ret; -} - -/* - * Move the just written object into its final resting place - */ -int move_temp_to_file(const char *tmpfile, char *filename) -{ - int ret = link_temp_to_file(tmpfile, filename); + if (object_creation_mode == OBJECT_CREATION_USES_RENAMES) + goto try_rename; + else if (link(tmpfile, filename)) + ret = errno; /* * Coda hack - coda doesn't like cross-directory links, @@ -1334,238 +2349,201 @@ int move_temp_to_file(const char *tmpfile, char *filename) * * The same holds for FAT formatted media. * - * When this succeeds, we just return 0. We have nothing + * When this succeeds, we just return. We have nothing * left to unlink. */ if (ret && ret != EEXIST) { + try_rename: if (!rename(tmpfile, filename)) - return 0; + goto out; ret = errno; } - unlink(tmpfile); + unlink_or_warn(tmpfile); if (ret) { if (ret != EEXIST) { - fprintf(stderr, "unable to write sha1 filename %s: %s\n", filename, strerror(ret)); - return -1; + return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret)); } /* FIXME!!! Collision check here ? */ } +out: + if (adjust_shared_perm(filename)) + return error("unable to set permission to '%s'", filename); return 0; } -int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1) +static int write_buffer(int fd, const void *buf, size_t len) { - int size; - unsigned char *compressed; - z_stream stream; - unsigned char sha1[20]; - char *filename; - static char tmpfile[PATH_MAX]; - unsigned char hdr[50]; - int fd, hdrlen; + if (write_in_full(fd, buf, len) < 0) + return error("file write error (%s)", strerror(errno)); + return 0; +} - /* Normally if we have it in the pack then we do not bother writing - * it out into .git/objects/??/?{38} file. - */ - filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); - if (returnsha1) - memcpy(returnsha1, sha1, 20); - if (has_sha1_file(sha1)) - return 0; - fd = open(filename, O_RDONLY); - if (fd >= 0) { - /* - * FIXME!!! We might do collision checking here, but we'd - * need to uncompress the old file and check it. Later. - */ - close(fd); +int hash_sha1_file(const void *buf, unsigned long len, const char *type, + unsigned char *sha1) +{ + char hdr[32]; + int hdrlen; + write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); + return 0; +} + +/* Finalize a file on disk, and close it. */ +static void close_sha1_file(int fd) +{ + if (fsync_object_files) + fsync_or_die(fd, "sha1 file"); + if (close(fd) != 0) + die_errno("error when closing sha1 file"); +} + +/* Size of directory component, including the ending '/' */ +static inline int directory_size(const char *filename) +{ + const char *s = strrchr(filename, '/'); + if (!s) return 0; - } + return s - filename + 1; +} - if (errno != ENOENT) { - fprintf(stderr, "sha1 file %s: %s\n", filename, strerror(errno)); +/* + * This creates a temporary file in the same directory as the final + * 'filename' + * + * We want to avoid cross-directory filename renames, because those + * can have problems on various filesystems (FAT, NFS, Coda). + */ +static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename) +{ + int fd, dirlen = directory_size(filename); + + if (dirlen + 20 > bufsiz) { + errno = ENAMETOOLONG; return -1; } + memcpy(buffer, filename, dirlen); + strcpy(buffer + dirlen, "tmp_obj_XXXXXX"); + fd = git_mkstemp_mode(buffer, 0444); + if (fd < 0 && dirlen && errno == ENOENT) { + /* Make sure the directory exists */ + memcpy(buffer, filename, dirlen); + buffer[dirlen-1] = 0; + if (mkdir(buffer, 0777) || adjust_shared_perm(buffer)) + return -1; - snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory()); + /* Try again */ + strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX"); + fd = git_mkstemp_mode(buffer, 0444); + } + return fd; +} + +static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen, + const void *buf, unsigned long len, time_t mtime) +{ + int fd, ret; + unsigned char compressed[4096]; + git_zstream stream; + git_SHA_CTX c; + unsigned char parano_sha1[20]; + char *filename; + static char tmpfile[PATH_MAX]; - fd = mkstemp(tmpfile); + filename = sha1_file_name(sha1); + fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename); if (fd < 0) { - fprintf(stderr, "unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno)); - return -1; + if (errno == EACCES) + return error("insufficient permission for adding an object to repository database %s\n", get_object_directory()); + else + return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno)); } /* Set it up */ memset(&stream, 0, sizeof(stream)); - deflateInit(&stream, Z_BEST_COMPRESSION); - size = deflateBound(&stream, len+hdrlen); - compressed = xmalloc(size); - - /* Compress it */ + git_deflate_init(&stream, zlib_compression_level); stream.next_out = compressed; - stream.avail_out = size; + stream.avail_out = sizeof(compressed); + git_SHA1_Init(&c); /* First header.. */ - stream.next_in = hdr; + stream.next_in = (unsigned char *)hdr; stream.avail_in = hdrlen; - while (deflate(&stream, 0) == Z_OK) - /* nothing */; + while (git_deflate(&stream, 0) == Z_OK) + ; /* nothing */ + git_SHA1_Update(&c, hdr, hdrlen); /* Then the data itself.. */ - stream.next_in = buf; + stream.next_in = (void *)buf; stream.avail_in = len; - while (deflate(&stream, Z_FINISH) == Z_OK) - /* nothing */; - deflateEnd(&stream); - size = stream.total_out; - - if (write(fd, compressed, size) != size) - die("unable to write file"); - fchmod(fd, 0444); - close(fd); - free(compressed); + do { + unsigned char *in0 = stream.next_in; + ret = git_deflate(&stream, Z_FINISH); + git_SHA1_Update(&c, in0, stream.next_in - in0); + if (write_buffer(fd, compressed, stream.next_out - compressed) < 0) + die("unable to write sha1 file"); + stream.next_out = compressed; + stream.avail_out = sizeof(compressed); + } while (ret == Z_OK); + + if (ret != Z_STREAM_END) + die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret); + ret = git_deflate_end_gently(&stream); + if (ret != Z_OK) + die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret); + git_SHA1_Final(parano_sha1, &c); + if (hashcmp(sha1, parano_sha1) != 0) + die("confused by unstable object source data for %s", sha1_to_hex(sha1)); + + close_sha1_file(fd); + + if (mtime) { + struct utimbuf utb; + utb.actime = mtime; + utb.modtime = mtime; + if (utime(tmpfile, &utb) < 0) + warning("failed utime() on %s: %s", + tmpfile, strerror(errno)); + } return move_temp_to_file(tmpfile, filename); } -int write_sha1_to_fd(int fd, const unsigned char *sha1) -{ - ssize_t size; - unsigned long objsize; - int posn = 0; - void *map = map_sha1_file_internal(sha1, &objsize); - void *buf = map; - void *temp_obj = NULL; - z_stream stream; - - if (!buf) { - unsigned char *unpacked; - unsigned long len; - char type[20]; - char hdr[50]; - int hdrlen; - // need to unpack and recompress it by itself - unpacked = read_packed_sha1(sha1, type, &len); - - hdrlen = sprintf(hdr, "%s %lu", type, len) + 1; - - /* Set it up */ - memset(&stream, 0, sizeof(stream)); - deflateInit(&stream, Z_BEST_COMPRESSION); - size = deflateBound(&stream, len + hdrlen); - temp_obj = buf = xmalloc(size); - - /* Compress it */ - stream.next_out = buf; - stream.avail_out = size; - - /* First header.. */ - stream.next_in = (void *)hdr; - stream.avail_in = hdrlen; - while (deflate(&stream, 0) == Z_OK) - /* nothing */; - - /* Then the data itself.. */ - stream.next_in = unpacked; - stream.avail_in = len; - while (deflate(&stream, Z_FINISH) == Z_OK) - /* nothing */; - deflateEnd(&stream); - free(unpacked); - - objsize = stream.total_out; - } - - do { - size = write(fd, buf + posn, objsize - posn); - if (size <= 0) { - if (!size) { - fprintf(stderr, "write closed\n"); - } else { - perror("write "); - } - return -1; - } - posn += size; - } while (posn < objsize); - - if (map) - munmap(map, objsize); - if (temp_obj) - free(temp_obj); +int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *returnsha1) +{ + unsigned char sha1[20]; + char hdr[32]; + int hdrlen; - return 0; + /* Normally if we have it in the pack then we do not bother writing + * it out into .git/objects/??/?{38} file. + */ + write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen); + if (returnsha1) + hashcpy(returnsha1, sha1); + if (has_sha1_file(sha1)) + return 0; + return write_loose_object(sha1, hdr, hdrlen, buf, len, 0); } -int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer, - size_t bufsize, size_t *bufposn) +int force_object_loose(const unsigned char *sha1, time_t mtime) { - char tmpfile[PATH_MAX]; - int local; - z_stream stream; - unsigned char real_sha1[20]; - unsigned char discard[4096]; + void *buf; + unsigned long len; + enum object_type type; + char hdr[32]; + int hdrlen; int ret; - SHA_CTX c; - - snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory()); - - local = mkstemp(tmpfile); - if (local < 0) - return error("Couldn't open %s for %s", - tmpfile, sha1_to_hex(sha1)); - - memset(&stream, 0, sizeof(stream)); - - inflateInit(&stream); - SHA1_Init(&c); - - do { - ssize_t size; - if (*bufposn) { - stream.avail_in = *bufposn; - stream.next_in = (unsigned char *) buffer; - do { - stream.next_out = discard; - stream.avail_out = sizeof(discard); - ret = inflate(&stream, Z_SYNC_FLUSH); - SHA1_Update(&c, discard, sizeof(discard) - - stream.avail_out); - } while (stream.avail_in && ret == Z_OK); - write(local, buffer, *bufposn - stream.avail_in); - memmove(buffer, buffer + *bufposn - stream.avail_in, - stream.avail_in); - *bufposn = stream.avail_in; - if (ret != Z_OK) - break; - } - size = read(fd, buffer + *bufposn, bufsize - *bufposn); - if (size <= 0) { - close(local); - unlink(tmpfile); - if (!size) - return error("Connection closed?"); - perror("Reading from connection"); - return -1; - } - *bufposn += size; - } while (1); - inflateEnd(&stream); - - close(local); - SHA1_Final(real_sha1, &c); - if (ret != Z_STREAM_END) { - unlink(tmpfile); - return error("File %s corrupted", sha1_to_hex(sha1)); - } - if (memcmp(sha1, real_sha1, 20)) { - unlink(tmpfile); - return error("File %s has bad hash", sha1_to_hex(sha1)); - } + if (has_loose_object(sha1)) + return 0; + buf = read_packed_sha1(sha1, &type, &len); + if (!buf) + return error("cannot read sha1_file for %s", sha1_to_hex(sha1)); + hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1; + ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime); + free(buf); - return move_temp_to_file(tmpfile, sha1_file_name(sha1)); + return ret; } int has_pack_index(const unsigned char *sha1) @@ -1576,14 +2554,6 @@ int has_pack_index(const unsigned char *sha1) return 1; } -int has_pack_file(const unsigned char *sha1) -{ - struct stat st; - if (stat(sha1_pack_name(sha1), &st)) - return 0; - return 1; -} - int has_sha1_pack(const unsigned char *sha1) { struct pack_entry e; @@ -1592,80 +2562,218 @@ int has_sha1_pack(const unsigned char *sha1) int has_sha1_file(const unsigned char *sha1) { - struct stat st; struct pack_entry e; if (find_pack_entry(sha1, &e)) return 1; - return find_sha1_file(sha1, &st) ? 1 : 0; + return has_loose_object(sha1); } -int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object) +static void check_tree(const void *buf, size_t size) { - unsigned long size = 4096; - char *buf = malloc(size); - int iret, ret; - unsigned long off = 0; - unsigned char hdr[50]; - int hdrlen; - do { - iret = read(fd, buf + off, size - off); - if (iret > 0) { - off += iret; - if (off == size) { - size *= 2; - buf = realloc(buf, size); - } + struct tree_desc desc; + struct name_entry entry; + + init_tree_desc(&desc, buf, size); + while (tree_entry(&desc, &entry)) + /* do nothing + * tree_entry() will die() on malformed entries */ + ; +} + +static void check_commit(const void *buf, size_t size) +{ + struct commit c; + memset(&c, 0, sizeof(c)); + if (parse_commit_buffer(&c, buf, size)) + die("corrupt commit"); +} + +static void check_tag(const void *buf, size_t size) +{ + struct tag t; + memset(&t, 0, sizeof(t)); + if (parse_tag_buffer(&t, buf, size)) + die("corrupt tag"); +} + +static int index_mem(unsigned char *sha1, void *buf, size_t size, + enum object_type type, + const char *path, unsigned flags) +{ + int ret, re_allocated = 0; + int write_object = flags & HASH_WRITE_OBJECT; + + if (!type) + type = OBJ_BLOB; + + /* + * Convert blobs to git internal format + */ + if ((type == OBJ_BLOB) && path) { + struct strbuf nbuf = STRBUF_INIT; + if (convert_to_git(path, buf, size, &nbuf, + write_object ? safe_crlf : 0)) { + buf = strbuf_detach(&nbuf, &size); + re_allocated = 1; } - } while (iret > 0); - if (iret < 0) { - free(buf); - return -1; } - if (!type) - type = "blob"; - if (write_object) - ret = write_sha1_file(buf, off, type, sha1); - else { - write_sha1_file_prepare(buf, off, type, sha1, hdr, &hdrlen); - ret = 0; + if (flags & HASH_FORMAT_CHECK) { + if (type == OBJ_TREE) + check_tree(buf, size); + if (type == OBJ_COMMIT) + check_commit(buf, size); + if (type == OBJ_TAG) + check_tag(buf, size); } - free(buf); + + if (write_object) + ret = write_sha1_file(buf, size, typename(type), sha1); + else + ret = hash_sha1_file(buf, size, typename(type), sha1); + if (re_allocated) + free(buf); return ret; } -int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type) +static int index_pipe(unsigned char *sha1, int fd, enum object_type type, + const char *path, unsigned flags) { - unsigned long size = st->st_size; - void *buf; + struct strbuf sbuf = STRBUF_INIT; int ret; - unsigned char hdr[50]; - int hdrlen; - buf = ""; - if (size) - buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); - close(fd); - if (buf == MAP_FAILED) - return -1; + if (strbuf_read(&sbuf, fd, 4096) >= 0) + ret = index_mem(sha1, sbuf.buf, sbuf.len, type, path, flags); + else + ret = -1; + strbuf_release(&sbuf); + return ret; +} - if (!type) - type = "blob"; - if (write_object) - ret = write_sha1_file(buf, size, type, sha1); - else { - write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen); - ret = 0; - } - if (size) +#define SMALL_FILE_SIZE (32*1024) + +static int index_core(unsigned char *sha1, int fd, size_t size, + enum object_type type, const char *path, + unsigned flags) +{ + int ret; + + if (!size) { + ret = index_mem(sha1, NULL, size, type, path, flags); + } else if (size <= SMALL_FILE_SIZE) { + char *buf = xmalloc(size); + if (size == read_in_full(fd, buf, size)) + ret = index_mem(sha1, buf, size, type, path, flags); + else + ret = error("short read %s", strerror(errno)); + free(buf); + } else { + void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); + ret = index_mem(sha1, buf, size, type, path, flags); munmap(buf, size); + } return ret; } -int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object) +/* + * This creates one packfile per large blob, because the caller + * immediately wants the result sha1, and fast-import can report the + * object name via marks mechanism only by closing the created + * packfile. + * + * This also bypasses the usual "convert-to-git" dance, and that is on + * purpose. We could write a streaming version of the converting + * functions and insert that before feeding the data to fast-import + * (or equivalent in-core API described above), but the primary + * motivation for trying to stream from the working tree file and to + * avoid mmaping it in core is to deal with large binary blobs, and + * by definition they do _not_ want to get any conversion. + */ +static int index_stream(unsigned char *sha1, int fd, size_t size, + enum object_type type, const char *path, + unsigned flags) +{ + struct child_process fast_import; + char export_marks[512]; + const char *argv[] = { "fast-import", "--quiet", export_marks, NULL }; + char tmpfile[512]; + char fast_import_cmd[512]; + char buf[512]; + int len, tmpfd; + + strcpy(tmpfile, git_path("hashstream_XXXXXX")); + tmpfd = git_mkstemp_mode(tmpfile, 0600); + if (tmpfd < 0) + die_errno("cannot create tempfile: %s", tmpfile); + if (close(tmpfd)) + die_errno("cannot close tempfile: %s", tmpfile); + sprintf(export_marks, "--export-marks=%s", tmpfile); + + memset(&fast_import, 0, sizeof(fast_import)); + fast_import.in = -1; + fast_import.argv = argv; + fast_import.git_cmd = 1; + if (start_command(&fast_import)) + die_errno("index-stream: git fast-import failed"); + + len = sprintf(fast_import_cmd, "blob\nmark :1\ndata %lu\n", + (unsigned long) size); + write_or_whine(fast_import.in, fast_import_cmd, len, + "index-stream: feeding fast-import"); + while (size) { + char buf[10240]; + size_t sz = size < sizeof(buf) ? size : sizeof(buf); + ssize_t actual; + + actual = read_in_full(fd, buf, sz); + if (actual < 0) + die_errno("index-stream: reading input"); + if (write_in_full(fast_import.in, buf, actual) != actual) + die_errno("index-stream: feeding fast-import"); + size -= actual; + } + if (close(fast_import.in)) + die_errno("index-stream: closing fast-import"); + if (finish_command(&fast_import)) + die_errno("index-stream: finishing fast-import"); + + tmpfd = open(tmpfile, O_RDONLY); + if (tmpfd < 0) + die_errno("index-stream: cannot open fast-import mark"); + len = read(tmpfd, buf, sizeof(buf)); + if (len < 0) + die_errno("index-stream: reading fast-import mark"); + if (close(tmpfd) < 0) + die_errno("index-stream: closing fast-import mark"); + if (unlink(tmpfile)) + die_errno("index-stream: unlinking fast-import mark"); + if (len != 44 || + memcmp(":1 ", buf, 3) || + get_sha1_hex(buf + 3, sha1)) + die_errno("index-stream: unexpected fast-import mark: <%s>", buf); + return 0; +} + +int index_fd(unsigned char *sha1, int fd, struct stat *st, + enum object_type type, const char *path, unsigned flags) +{ + int ret; + size_t size = xsize_t(st->st_size); + + if (!S_ISREG(st->st_mode)) + ret = index_pipe(sha1, fd, type, path, flags); + else if (size <= big_file_threshold || type != OBJ_BLOB) + ret = index_core(sha1, fd, size, type, path, flags); + else + ret = index_stream(sha1, fd, size, type, path, flags); + close(fd); + return ret; +} + +int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags) { int fd; - char *target; + struct strbuf sb = STRBUF_INIT; switch (st->st_mode & S_IFMT) { case S_IFREG: @@ -1673,30 +2781,52 @@ int index_path(unsigned char *sha1, const char *path, struct stat *st, int write if (fd < 0) return error("open(\"%s\"): %s", path, strerror(errno)); - if (index_fd(sha1, fd, st, write_object, NULL) < 0) + if (index_fd(sha1, fd, st, OBJ_BLOB, path, flags) < 0) return error("%s: failed to insert into database", path); break; case S_IFLNK: - target = xmalloc(st->st_size+1); - if (readlink(path, target, st->st_size+1) != st->st_size) { + if (strbuf_readlink(&sb, path, st->st_size)) { char *errstr = strerror(errno); - free(target); return error("readlink(\"%s\"): %s", path, errstr); } - if (!write_object) { - unsigned char hdr[50]; - int hdrlen; - write_sha1_file_prepare(target, st->st_size, "blob", - sha1, hdr, &hdrlen); - } else if (write_sha1_file(target, st->st_size, "blob", sha1)) + if (!(flags & HASH_WRITE_OBJECT)) + hash_sha1_file(sb.buf, sb.len, blob_type, sha1); + else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1)) return error("%s: failed to insert into database", path); - free(target); + strbuf_release(&sb); break; + case S_IFDIR: + return resolve_gitlink_ref(path, "HEAD", sha1); default: return error("%s: unsupported file type", path); } return 0; } + +int read_pack_header(int fd, struct pack_header *header) +{ + if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header)) + /* "eof before pack header was fully read" */ + return PH_ERROR_EOF; + + if (header->hdr_signature != htonl(PACK_SIGNATURE)) + /* "protocol error (pack signature mismatch detected)" */ + return PH_ERROR_PACK_SIGNATURE; + if (!pack_version_ok(header->hdr_version)) + /* "protocol error (pack version unsupported)" */ + return PH_ERROR_PROTOCOL; + return 0; +} + +void assert_sha1_type(const unsigned char *sha1, enum object_type expect) +{ + enum object_type type = sha1_object_info(sha1, NULL); + if (type < 0) + die("%s is not a valid object", sha1_to_hex(sha1)); + if (type != expect) + die("%s is not a valid '%s' object", sha1_to_hex(sha1), + typename(expect)); +} |