diff options
Diffstat (limited to 'sha1_file.c')
-rw-r--r-- | sha1_file.c | 198 |
1 files changed, 144 insertions, 54 deletions
diff --git a/sha1_file.c b/sha1_file.c index b114cc922d..8e27db1bd2 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -36,6 +36,9 @@ static inline uintmax_t sz_fmt(size_t s) { return s; } const unsigned char null_sha1[20]; +static const char *no_log_pack_access = "no_log_pack_access"; +static const char *log_pack_access; + /* * 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 @@ -1303,6 +1306,26 @@ static int git_open_noatime(const char *name) } } +static int stat_sha1_file(const unsigned char *sha1, struct stat *st) +{ + char *name = sha1_file_name(sha1); + struct alternate_object_database *alt; + + if (!lstat(name, st)) + return 0; + + prepare_alt_odb(); + errno = ENOENT; + for (alt = alt_odb_list; alt; alt = alt->next) { + name = alt->name; + fill_sha1_path(name, sha1); + if (!lstat(alt->base, st)) + return 0; + } + + return -1; +} + static int open_sha1_file(const unsigned char *sha1) { int fd; @@ -1690,46 +1713,21 @@ static int retry_bad_packed_offset(struct packed_git *p, off_t obj_offset) return type; } - #define POI_STACK_PREALLOC 64 -static int packed_object_info(struct packed_git *p, off_t obj_offset, - unsigned long *sizep, int *rtype) +static enum object_type packed_to_object_type(struct packed_git *p, + off_t obj_offset, + enum object_type type, + struct pack_window **w_curs, + off_t curpos) { - struct pack_window *w_curs = NULL; - unsigned long size; - off_t curpos = obj_offset; - enum object_type type; off_t small_poi_stack[POI_STACK_PREALLOC]; off_t *poi_stack = small_poi_stack; int poi_stack_nr = 0, poi_stack_alloc = POI_STACK_PREALLOC; - type = unpack_object_header(p, &w_curs, &curpos, &size); - - if (rtype) - *rtype = type; /* representation type */ - - if (sizep) { - if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { - off_t tmp_pos = curpos; - off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos, - type, obj_offset); - if (!base_offset) { - type = OBJ_BAD; - goto out; - } - *sizep = get_size_from_delta(p, &w_curs, tmp_pos); - if (*sizep == 0) { - type = OBJ_BAD; - goto out; - } - } else { - *sizep = size; - } - } - while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { off_t base_offset; + unsigned long size; /* Push the object we're going to leave behind */ if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) { poi_stack_alloc = alloc_nr(poi_stack_nr); @@ -1740,11 +1738,11 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset, } poi_stack[poi_stack_nr++] = obj_offset; /* If parsing the base offset fails, just unwind */ - base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset); + base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset); if (!base_offset) goto unwind; curpos = obj_offset = base_offset; - type = unpack_object_header(p, &w_curs, &curpos, &size); + type = unpack_object_header(p, w_curs, &curpos, &size); if (type <= OBJ_NONE) { /* If getting the base itself fails, we first * retry the base, otherwise unwind */ @@ -1771,7 +1769,6 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset, out: if (poi_stack != small_poi_stack) free(poi_stack); - unuse_pack(&w_curs); return type; unwind: @@ -1785,6 +1782,57 @@ unwind: goto out; } +static int packed_object_info(struct packed_git *p, off_t obj_offset, + struct object_info *oi) +{ + struct pack_window *w_curs = NULL; + unsigned long size; + off_t curpos = obj_offset; + enum object_type type; + + /* + * We always get the representation type, but only convert it to + * a "real" type later if the caller is interested. + */ + type = unpack_object_header(p, &w_curs, &curpos, &size); + + if (oi->sizep) { + if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) { + off_t tmp_pos = curpos; + off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos, + type, obj_offset); + if (!base_offset) { + type = OBJ_BAD; + goto out; + } + *oi->sizep = get_size_from_delta(p, &w_curs, tmp_pos); + if (*oi->sizep == 0) { + type = OBJ_BAD; + goto out; + } + } else { + *oi->sizep = size; + } + } + + if (oi->disk_sizep) { + struct revindex_entry *revidx = find_pack_revindex(p, obj_offset); + *oi->disk_sizep = revidx[1].offset - obj_offset; + } + + if (oi->typep) { + *oi->typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos); + if (*oi->typep < 0) { + type = OBJ_BAD; + goto out; + } + } + +out: + unuse_pack(&w_curs); + return type; +} + static void *unpack_compressed_entry(struct packed_git *p, struct pack_window **w_curs, off_t curpos, @@ -1956,12 +2004,19 @@ static void write_pack_access_log(struct packed_git *p, off_t obj_offset) { static FILE *log_file; + if (!log_pack_access) + log_pack_access = getenv("GIT_TRACE_PACK_ACCESS"); + if (!log_pack_access) + log_pack_access = no_log_pack_access; + if (log_pack_access == no_log_pack_access) + return; + 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; + log_pack_access = no_log_pack_access; return; } } @@ -1992,7 +2047,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset, int delta_stack_nr = 0, delta_stack_alloc = UNPACK_ENTRY_STACK_PREALLOC; int base_from_cache = 0; - if (log_pack_access) + if (log_pack_access != no_log_pack_access) write_pack_access_log(p, obj_offset); /* PHASE 1: drill down to the innermost base object */ @@ -2135,8 +2190,17 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset, data = patch_delta(base, base_size, delta_data, delta_size, &size); + + /* + * We could not apply the delta; warn the user, but keep going. + * Our failure will be noticed either in the next iteration of + * the loop, or if this is the final delta, in the caller when + * we return NULL. Those code paths will take care of making + * a more explicit warning and retrying with another copy of + * the object. + */ if (!data) - die("failed to apply delta"); + error("failed to apply delta"); free(delta_data); } @@ -2338,7 +2402,8 @@ struct packed_git *find_sha1_pack(const unsigned char *sha1, } -static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep) +static int sha1_loose_object_info(const unsigned char *sha1, + struct object_info *oi) { int status; unsigned long mapsize, size; @@ -2346,19 +2411,37 @@ static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *size git_zstream stream; char hdr[32]; + /* + * If we don't care about type or size, then we don't + * need to look inside the object at all. + */ + if (!oi->typep && !oi->sizep) { + if (oi->disk_sizep) { + struct stat st; + if (stat_sha1_file(sha1, &st) < 0) + return -1; + *oi->disk_sizep = st.st_size; + } + return 0; + } + map = map_sha1_file(sha1, &mapsize); if (!map) - return error("unable to find %s", sha1_to_hex(sha1)); + return -1; + if (oi->disk_sizep) + *oi->disk_sizep = mapsize; if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) status = error("unable to unpack %s header", sha1_to_hex(sha1)); else if ((status = parse_sha1_header(hdr, &size)) < 0) status = error("unable to parse %s header", sha1_to_hex(sha1)); - else if (sizep) - *sizep = size; + else if (oi->sizep) + *oi->sizep = size; git_inflate_end(&stream); munmap(map, mapsize); - return status; + if (oi->typep) + *oi->typep = status; + return 0; } /* returns enum object_type or negative */ @@ -2366,34 +2449,37 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi) { struct cached_object *co; struct pack_entry e; - int status, rtype; + int rtype; co = find_cached_object(sha1); if (co) { + if (oi->typep) + *(oi->typep) = co->type; if (oi->sizep) *(oi->sizep) = co->size; + if (oi->disk_sizep) + *(oi->disk_sizep) = 0; oi->whence = OI_CACHED; - return co->type; + return 0; } if (!find_pack_entry(sha1, &e)) { /* Most likely it's a loose object. */ - status = sha1_loose_object_info(sha1, oi->sizep); - if (status >= 0) { + if (!sha1_loose_object_info(sha1, oi)) { oi->whence = OI_LOOSE; - return status; + return 0; } /* Not a loose object; someone else may have just packed it. */ reprepare_packed_git(); if (!find_pack_entry(sha1, &e)) - return status; + return -1; } - status = packed_object_info(e.p, e.offset, oi->sizep, &rtype); - if (status < 0) { + rtype = packed_object_info(e.p, e.offset, oi); + if (rtype < 0) { mark_bad_packed_object(e.p, sha1); - status = sha1_object_info_extended(sha1, oi); + return sha1_object_info_extended(sha1, oi); } else if (in_delta_base_cache(e.p, e.offset)) { oi->whence = OI_DBCACHED; } else { @@ -2404,15 +2490,19 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi) rtype == OBJ_OFS_DELTA); } - return status; + return 0; } int sha1_object_info(const unsigned char *sha1, unsigned long *sizep) { - struct object_info oi; + enum object_type type; + struct object_info oi = {NULL}; + oi.typep = &type; oi.sizep = sizep; - return sha1_object_info_extended(sha1, &oi); + if (sha1_object_info_extended(sha1, &oi) < 0) + return -1; + return type; } static void *read_packed_sha1(const unsigned char *sha1, |