[PATCH 06/10] get_short_sha1: NUL-terminate hex prefix
- From
Jeff King <peff@peff.net>
- Date
- Sep 26, 2016, 12:00 UTC
- Message-ID
- <20160926120007.eswpfrzs2ed66d2o@sigill.intra.peff.net>
- In-Reply-To
- <20160926115720.p2yb22lcq37gboon@sigill.intra.peff.net>
We store the hex prefix in a 40-byte buffer with the prefix itself followed by 40-minus-len "x" characters. These x's serve no purpose, and the lack of NUL termination makes the prefix string annoying to use. Let's just terminate it.
Note that this is in contrast to the binary prefix, which _must_ be zero-padded, because we look at the whole thing during a binary search to find the first potential match in each pack index. The loose-object hex search cannot use the same trick because it has to do a linear walk through the unsorted results of readdir() (and even if it could, you'd want zeroes instead of x's).
Signed-off-by: Jeff King <peff@peff.net> --- sha1_name.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/sha1_name.c b/sha1_name.c index 79eb1ee..549ef3f 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -14,7 +14,7 @@ typedef int (*disambiguate_hint_fn)(const unsigned char *, void *); struct disambiguate_state { int len; /* length of prefix in hex chars */ - char hex_pfx[GIT_SHA1_HEXSZ]; + char hex_pfx[GIT_SHA1_HEXSZ + 1]; unsigned char bin_pfx[GIT_SHA1_RAWSZ]; disambiguate_hint_fn fn; @@ -291,7 +291,6 @@ static int init_object_disambiguation(const char *name, int len, return -1; memset(ds, 0, sizeof(*ds)); - memset(ds->hex_pfx, 'x', GIT_SHA1_HEXSZ); for (i = 0; i < len ;i++) { unsigned char c = name[i]; @@ -313,6 +312,7 @@ static int init_object_disambiguation(const char *name, int len, } ds->len = len; + ds->hex_pfx[len] = '\0'; prepare_alt_odb(); return 0; } @@ -351,7 +351,7 @@ static int get_short_sha1(const char *name, int len, unsigned char *sha1, status = finish_object_disambiguation(&ds, sha1); if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) - return error("short SHA1 %.*s is ambiguous.", ds.len, ds.hex_pfx); + return error("short SHA1 %s is ambiguous.", ds.hex_pfx); return status; }
-- 2.10.0.492.g14f803f