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Diffstat (limited to 'sha1_file.c')
-rw-r--r--sha1_file.c311
1 files changed, 155 insertions, 156 deletions
diff --git a/sha1_file.c b/sha1_file.c
index 06c809aeeb..34d527f670 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -60,6 +60,12 @@ static struct cached_object empty_tree = {
0
};
+/*
+ * A pointer to the last packed_git in which an object was found.
+ * When an object is sought, we look in this packfile first, because
+ * objects that are looked up at similar times are often in the same
+ * packfile as one another.
+ */
static struct packed_git *last_found_pack;
static struct cached_object *find_cached_object(const unsigned char *sha1)
@@ -105,50 +111,63 @@ int mkdir_in_gitdir(const char *path)
return adjust_shared_perm(path);
}
-int safe_create_leading_directories(char *path)
+enum scld_error safe_create_leading_directories(char *path)
{
- char *pos = path + offset_1st_component(path);
- struct stat st;
+ char *next_component = path + offset_1st_component(path);
+ enum scld_error ret = SCLD_OK;
+
+ while (ret == SCLD_OK && next_component) {
+ struct stat st;
+ char *slash = next_component, slash_character;
+
+ while (*slash && !is_dir_sep(*slash))
+ slash++;
- while (pos) {
- pos = strchr(pos, '/');
- if (!pos)
+ if (!*slash)
break;
- while (*++pos == '/')
- ;
- if (!*pos)
+
+ next_component = slash + 1;
+ while (is_dir_sep(*next_component))
+ next_component++;
+ if (!*next_component)
break;
- *--pos = '\0';
+
+ slash_character = *slash;
+ *slash = '\0';
if (!stat(path, &st)) {
/* path exists */
- if (!S_ISDIR(st.st_mode)) {
- *pos = '/';
- return -3;
- }
- }
- else if (mkdir(path, 0777)) {
+ if (!S_ISDIR(st.st_mode))
+ ret = SCLD_EXISTS;
+ } else if (mkdir(path, 0777)) {
if (errno == EEXIST &&
- !stat(path, &st) && S_ISDIR(st.st_mode)) {
+ !stat(path, &st) && S_ISDIR(st.st_mode))
; /* somebody created it since we checked */
- } else {
- *pos = '/';
- return -1;
- }
- }
- else if (adjust_shared_perm(path)) {
- *pos = '/';
- return -2;
+ else if (errno == ENOENT)
+ /*
+ * Either mkdir() failed because
+ * somebody just pruned the containing
+ * directory, or stat() failed because
+ * the file that was in our way was
+ * just removed. Either way, inform
+ * the caller that it might be worth
+ * trying again:
+ */
+ ret = SCLD_VANISHED;
+ else
+ ret = SCLD_FAILED;
+ } else if (adjust_shared_perm(path)) {
+ ret = SCLD_PERMS;
}
- *pos++ = '/';
+ *slash = slash_character;
}
- return 0;
+ return ret;
}
-int safe_create_leading_directories_const(const char *path)
+enum scld_error safe_create_leading_directories_const(const char *path)
{
/* path points to cache entries, so xstrdup before messing with it */
char *buf = xstrdup(path);
- int result = safe_create_leading_directories(buf);
+ enum scld_error result = safe_create_leading_directories(buf);
free(buf);
return result;
}
@@ -165,17 +184,7 @@ 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 an "xstrdup()" if you need to save the
- * filename.
- *
- * Also note that this returns the location for creating. Reading
- * SHA1 file can happen from any alternate directory listed in the
- * DB_ENVIRONMENT environment variable if it is not found in
- * the primary object database.
- */
-char *sha1_file_name(const unsigned char *sha1)
+const char *sha1_file_name(const unsigned char *sha1)
{
static char buf[PATH_MAX];
const char *objdir;
@@ -195,6 +204,11 @@ char *sha1_file_name(const unsigned char *sha1)
return buf;
}
+/*
+ * Return the name of the pack or index file with the specified sha1
+ * in its filename. *base and *name are scratch space that must be
+ * provided by the caller. which should be "pack" or "idx".
+ */
static char *sha1_get_pack_name(const unsigned char *sha1,
char **name, char **base, const char *which)
{
@@ -239,8 +253,6 @@ char *sha1_pack_index_name(const unsigned char *sha1)
struct alternate_object_database *alt_odb_list;
static struct alternate_object_database **alt_odb_tail;
-static int git_open_noatime(const char *name);
-
/*
* Prepare alternate object database registry.
*
@@ -425,8 +437,7 @@ void prepare_alt_odb(void)
static int has_loose_object_local(const unsigned char *sha1)
{
- char *name = sha1_file_name(sha1);
- return !access(name, F_OK);
+ return !access(sha1_file_name(sha1), F_OK);
}
int has_loose_object_nonlocal(const unsigned char *sha1)
@@ -478,7 +489,12 @@ void pack_report(void)
sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
}
-static int check_packed_git_idx(const char *path, struct packed_git *p)
+/*
+ * Open and mmap the index file at path, perform a couple of
+ * consistency checks, then record its information to p. Return 0 on
+ * success.
+ */
+static int check_packed_git_idx(const char *path, struct packed_git *p)
{
void *idx_map;
struct pack_idx_header *hdr;
@@ -774,7 +790,7 @@ void close_pack_index(struct packed_git *p)
* 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
+ * replaced on disk. Of course no index pointers or windows for given pack
* must subsist at this point. If ever objects from this pack are requested
* again, the new version of the pack will be reinitialized through
* reprepare_packed_git().
@@ -1110,7 +1126,7 @@ static void report_helper(const struct string_list *list,
const char *msg;
switch (seen_bits) {
case 0:
- msg = "no corresponding .idx nor .pack";
+ msg = "no corresponding .idx or .pack";
break;
case 1:
msg = "no corresponding .idx";
@@ -1219,6 +1235,7 @@ static void prepare_packed_git_one(char *objdir, int local)
if (has_extension(de->d_name, ".idx") ||
has_extension(de->d_name, ".pack") ||
+ has_extension(de->d_name, ".bitmap") ||
has_extension(de->d_name, ".keep"))
string_list_append(&garbage, path);
else
@@ -1303,7 +1320,6 @@ void prepare_packed_git(void)
void reprepare_packed_git(void)
{
- discard_revindex();
prepare_packed_git_run_once = 0;
prepare_packed_git();
}
@@ -1380,7 +1396,7 @@ int check_sha1_signature(const unsigned char *sha1, void *map,
return hashcmp(sha1, real_sha1) ? -1 : 0;
}
-static int git_open_noatime(const char *name)
+int git_open_noatime(const char *name)
{
static int sha1_file_open_flag = O_NOATIME;
@@ -1401,17 +1417,15 @@ 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))
+ if (!lstat(sha1_file_name(sha1), 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);
+ fill_sha1_path(alt->name, sha1);
if (!lstat(alt->base, st))
return 0;
}
@@ -1422,22 +1436,24 @@ static int stat_sha1_file(const unsigned char *sha1, struct stat *st)
static int open_sha1_file(const unsigned char *sha1)
{
int fd;
- char *name = sha1_file_name(sha1);
struct alternate_object_database *alt;
+ int most_interesting_errno;
- fd = git_open_noatime(name);
+ fd = git_open_noatime(sha1_file_name(sha1));
if (fd >= 0)
return fd;
+ most_interesting_errno = errno;
prepare_alt_odb();
- errno = ENOENT;
for (alt = alt_odb_list; alt; alt = alt->next) {
- name = alt->name;
- fill_sha1_path(name, sha1);
+ fill_sha1_path(alt->name, sha1);
fd = git_open_noatime(alt->base);
if (fd >= 0)
return fd;
+ if (most_interesting_errno == ENOENT)
+ most_interesting_errno = errno;
}
+ errno = most_interesting_errno;
return -1;
}
@@ -1465,51 +1481,6 @@ void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
return map;
}
-/*
- * 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)
{
@@ -1537,14 +1508,6 @@ unsigned long unpack_object_header_buffer(const unsigned char *buf,
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;
@@ -1552,27 +1515,6 @@ int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long ma
stream->next_out = buffer;
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;
-
- /* 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);
}
@@ -1764,6 +1706,38 @@ static off_t get_delta_base(struct packed_git *p,
return base_offset;
}
+/*
+ * Like get_delta_base above, but we return the sha1 instead of the pack
+ * offset. This means it is cheaper for REF deltas (we do not have to do
+ * the final object lookup), but more expensive for OFS deltas (we
+ * have to load the revidx to convert the offset back into a sha1).
+ */
+static const unsigned char *get_delta_base_sha1(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t curpos,
+ enum object_type type,
+ off_t delta_obj_offset)
+{
+ if (type == OBJ_REF_DELTA) {
+ unsigned char *base = use_pack(p, w_curs, curpos, NULL);
+ return base;
+ } else if (type == OBJ_OFS_DELTA) {
+ struct revindex_entry *revidx;
+ off_t base_offset = get_delta_base(p, w_curs, &curpos,
+ type, delta_obj_offset);
+
+ if (!base_offset)
+ return NULL;
+
+ revidx = find_pack_revindex(p, base_offset);
+ if (!revidx)
+ return NULL;
+
+ return nth_packed_object_sha1(p, revidx->nr);
+ } else
+ return NULL;
+}
+
int unpack_object_header(struct packed_git *p,
struct pack_window **w_curs,
off_t *curpos,
@@ -1921,6 +1895,22 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset,
}
}
+ if (oi->delta_base_sha1) {
+ if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
+ const unsigned char *base;
+
+ base = get_delta_base_sha1(p, &w_curs, curpos,
+ type, obj_offset);
+ if (!base) {
+ type = OBJ_BAD;
+ goto out;
+ }
+
+ hashcpy(oi->delta_base_sha1, base);
+ } else
+ hashclr(oi->delta_base_sha1);
+ }
+
out:
unuse_pack(&w_curs);
return type;
@@ -2302,6 +2292,10 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
*final_size = size;
unuse_pack(&w_curs);
+
+ if (delta_stack != small_delta_stack)
+ free(delta_stack);
+
return data;
}
@@ -2461,6 +2455,10 @@ static int fill_pack_entry(const unsigned char *sha1,
return 1;
}
+/*
+ * Iff a pack file contains the object named by sha1, return true and
+ * store its location to e.
+ */
static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
{
struct packed_git *p;
@@ -2473,11 +2471,13 @@ static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
return 1;
for (p = packed_git; p; p = p->next) {
- if (p == last_found_pack || !fill_pack_entry(sha1, e, p))
- continue;
+ if (p == last_found_pack)
+ continue; /* we already checked this one */
- last_found_pack = p;
- return 1;
+ if (fill_pack_entry(sha1, e, p)) {
+ last_found_pack = p;
+ return 1;
+ }
}
return 0;
}
@@ -2504,6 +2504,9 @@ static int sha1_loose_object_info(const unsigned char *sha1,
git_zstream stream;
char hdr[32];
+ if (oi->delta_base_sha1)
+ hashclr(oi->delta_base_sha1);
+
/*
* If we don't care about type or size, then we don't
* need to look inside the object at all. Note that we
@@ -2540,13 +2543,14 @@ static int sha1_loose_object_info(const unsigned char *sha1,
return 0;
}
-int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
+int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi, unsigned flags)
{
struct cached_object *co;
struct pack_entry e;
int rtype;
+ const unsigned char *real = lookup_replace_object_extended(sha1, flags);
- co = find_cached_object(sha1);
+ co = find_cached_object(real);
if (co) {
if (oi->typep)
*(oi->typep) = co->type;
@@ -2554,27 +2558,29 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
*(oi->sizep) = co->size;
if (oi->disk_sizep)
*(oi->disk_sizep) = 0;
+ if (oi->delta_base_sha1)
+ hashclr(oi->delta_base_sha1);
oi->whence = OI_CACHED;
return 0;
}
- if (!find_pack_entry(sha1, &e)) {
+ if (!find_pack_entry(real, &e)) {
/* Most likely it's a loose object. */
- if (!sha1_loose_object_info(sha1, oi)) {
+ if (!sha1_loose_object_info(real, oi)) {
oi->whence = OI_LOOSE;
return 0;
}
/* Not a loose object; someone else may have just packed it. */
reprepare_packed_git();
- if (!find_pack_entry(sha1, &e))
+ if (!find_pack_entry(real, &e))
return -1;
}
rtype = packed_object_info(e.p, e.offset, oi);
if (rtype < 0) {
- mark_bad_packed_object(e.p, sha1);
- return sha1_object_info_extended(sha1, oi);
+ mark_bad_packed_object(e.p, real);
+ return sha1_object_info_extended(real, oi, 0);
} else if (in_delta_base_cache(e.p, e.offset)) {
oi->whence = OI_DBCACHED;
} else {
@@ -2596,7 +2602,7 @@ int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
oi.typep = &type;
oi.sizep = sizep;
- if (sha1_object_info_extended(sha1, &oi) < 0)
+ if (sha1_object_info_extended(sha1, &oi, LOOKUP_REPLACE_OBJECT) < 0)
return -1;
return type;
}
@@ -2633,12 +2639,7 @@ int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
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);
- }
+ ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
co = &cached_objects[cached_object_nr++];
co->size = len;
co->type = type;
@@ -2686,10 +2687,8 @@ void *read_sha1_file_extended(const unsigned char *sha1,
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;
+ const unsigned char *repl = lookup_replace_object_extended(sha1, flag);
errno = 0;
data = read_object(repl, type, size);
@@ -2705,7 +2704,8 @@ void *read_sha1_file_extended(const unsigned char *sha1,
sha1_to_hex(repl), sha1_to_hex(sha1));
if (has_loose_object(repl)) {
- path = sha1_file_name(sha1);
+ const char *path = sha1_file_name(sha1);
+
die("loose object %s (stored in %s) is corrupt",
sha1_to_hex(repl), path);
}
@@ -2903,10 +2903,9 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
git_zstream stream;
git_SHA_CTX c;
unsigned char parano_sha1[20];
- char *filename;
static char tmp_file[PATH_MAX];
+ const char *filename = sha1_file_name(sha1);
- filename = sha1_file_name(sha1);
fd = create_tmpfile(tmp_file, sizeof(tmp_file), filename);
if (fd < 0) {
if (errno == EACCES)
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 06:20:56 +0000