mirrors/git
0
0
Fork 0
mirror of https://github.com/git/git.git synced 2024-11-23 18:05:29 +08:00
Code Issues Packages Projects Releases Wiki Activity

hex: default to the_hash_algo on zero algorithm value

Browse Source 
There are numerous places in the codebase where we assume we can
initialize data by zeroing all its bytes.  However, when we do that with
a struct object_id, it leaves the structure with a zero value for the
algorithm, which is invalid.

We could forbid this pattern and require that all struct object_id
instances be initialized using oidclr, but this seems burdensome and
it's unnatural to most C programmers.  Instead, if the algorithm is
zero, assume we wanted to use the default hash algorithm instead.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
brian m. carlson 2021-04-26 01:03:00 +00:00 committed by Junio C Hamano
parent 71b7672b67
commit b8505ecbf2
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
hex.c
View File

@ -124,6 +124,13 @@ char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash,
char *buf = buffer;
int i;
/*
* Our struct object_id has been memset to 0, so default to printing
* using the default hash.
*/
if (algop == &hash_algos[0])
algop = the_hash_algo;
for (i = 0; i < algop->rawsz; i++) {
unsigned int val = *hash++;
*buf++ = hex[val >> 4];