@matheusbsbs / matheus-bagliano / commits / 33e42de0d2

fsck: give accurate error message on empty loose object files

Since 3ba7a065527a (A loose object is not corrupt if it cannot be read due to EMFILE), "git fsck" on a repository with an empty loose object file complains with the error message fatal: failed to read object <sha1>: Invalid argument This comes from a failure of mmap on this empty file, which sets errno to EINVAL. Instead of calling xmmap on empty file, we display a clean error message ourselves, and return a NULL pointer. The new message is error: object file .git/objects/09/<rest-of-sha1> is empty fatal: loose object <sha1> (stored in .git/objects/09/<rest-of-sha1>) is corrupt The second line was already there before the regression in 3ba7a065527a, and the first is an additional message, that should help diagnosing the problem for the user. Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Matthieu Moy committed Feb 6, 2012 at 17:24 UTC 33e42de0d21a8365496e904235bd32fd4659300d

1 file changed +5

sha1_file.c

@@ -1070,6 +1070,11 @@ static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)

1070

1071 if (!fstat(fd, &st)) {

1072 *size = xsize_t(st.st_size);

1073 + if (!*size) {

1074 + /* mmap() is forbidden on empty files */

1075 + error("object file %s is empty", sha1_file_name(sha1));

1076 + return NULL;

1077 + }

1078 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);

1079 }

1080 close(fd);