[PATCH 3/5] optimize parse_sha1_header() a little by detecting object type
Signed-off-by: Liu Yubao <yubao.liu@gmail.com>
---
sha1_file.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/sha1_file.c b/sha1_file.c
index dccc455..79062f0 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1099,7 +1099,8 @@ static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
if (!fstat(fd, &st)) {
*size = xsize_t(st.st_size);
- map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (*size > 0)
+ map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
}
close(fd);
}
@@ -1257,6 +1258,8 @@ static int parse_sha1_header(const char *hdr, unsigned long length, unsigned lon
* terminating '\0' that we add), and is followed by
* a space, at least one byte for size, and a '\0'.
*/
+ if ('b' != *hdr && 'c' != *hdr && 't' != *hdr) /* blob/commit/tag/tree */
+ return -1;
i = 0;
while (hdr < hdr_end - 2) {
char c = *hdr++;
--
1.6.1.rc1.5.gde86c