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Diffstat (limited to 'sha1_file.c')
-rw-r--r--sha1_file.c92
1 files changed, 68 insertions, 24 deletions
diff --git a/sha1_file.c b/sha1_file.c
index 89d7e5eb5..340130144 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -248,27 +248,30 @@ static int link_alt_odb_entry(const char * entry, int len, const char * relative
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;
+ int pfxlen, entlen;
+ struct strbuf pathbuf = STRBUF_INIT;
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;
+ strbuf_addstr(&pathbuf, real_path(relative_base));
+ strbuf_addch(&pathbuf, '/');
}
- ent = xmalloc(sizeof(*ent) + entlen);
+ strbuf_add(&pathbuf, entry, len);
- 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);
+ normalize_path_copy(pathbuf.buf, pathbuf.buf);
+
+ pfxlen = strlen(pathbuf.buf);
+
+ /*
+ * The trailing slash after the directory name is given by
+ * this function at the end. Remove duplicates.
+ */
+ while (pfxlen && pathbuf.buf[pfxlen-1] == '/')
+ pfxlen -= 1;
+
+ entlen = pfxlen + 43; /* '/' + 2 hex + '/' + 38 hex + NUL */
+ ent = xmalloc(sizeof(*ent) + entlen);
+ memcpy(ent->base, pathbuf.buf, pfxlen);
+ strbuf_release(&pathbuf);
ent->name = ent->base + pfxlen + 1;
ent->base[pfxlen + 3] = '/';
@@ -380,7 +383,7 @@ 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/objects\n", reference);
+ char *alt = mkpath("%s\n", reference);
write_or_die(fd, alt, strlen(alt));
if (commit_lock_file(lock))
die("could not close alternates file");
@@ -1217,14 +1220,34 @@ static int experimental_loose_object(unsigned char *map)
unsigned int word;
/*
- * Is it a zlib-compressed buffer? If so, the first byte
- * must be 0x78 (15-bit window size, deflated), and the
- * first 16-bit word is evenly divisible by 31. If so,
- * we are looking at the official format, not the experimental
- * one.
+ * 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] == 0x78 && !(word % 31))
+ if ((map[0] & 0x8F) == 0x08 && !(word % 31))
return 0;
else
return 1;
@@ -1797,6 +1820,24 @@ static void *unpack_delta_entry(struct packed_git *p,
return result;
}
+static void write_pack_access_log(struct packed_git *p, off_t obj_offset)
+{
+ 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;
+ }
+ }
+ fprintf(log_file, "%s %"PRIuMAX"\n",
+ p->pack_name, (uintmax_t)obj_offset);
+ fflush(log_file);
+}
+
int do_check_packed_object_crc;
void *unpack_entry(struct packed_git *p, off_t obj_offset,
@@ -1806,6 +1847,9 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
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;