path: root/builtin/describe.c
diff options
authorLinus Torvalds <>2010-10-28 18:28:04 (GMT)
committerJunio C Hamano <>2011-03-11 22:42:54 (GMT)
commitdce96489162b05ae3463741f7f0365ff56f0de36 (patch)
treeb342bc64b96a6553e58c0a29a1225c0d7832e9b4 /builtin/describe.c
parent7ed863a85a6ce2c4ac4476848310b8f917ab41f9 (diff)
Make the default abbrev length configurable
The default of 7 comes from fairly early in git development, when seven hex digits was a lot (it covers about 250+ million hash values). Back then I thought that 65k revisions was a lot (it was what we were about to hit in BK), and each revision tends to be about 5-10 new objects or so, so a million objects was a big number. These days, the kernel isn't even the largest git project, and even the kernel has about 220k revisions (_much_ bigger than the BK tree ever was) and we are approaching two million objects. At that point, seven hex digits is still unique for a lot of them, but when we're talking about just two orders of magnitude difference between number of objects and the hash size, there _will_ be collisions in truncated hash values. It's no longer even close to unrealistic - it happens all the time. We should both increase the default abbrev that was unrealistically small, _and_ add a way for people to set their own default per-project in the git config file. This is the first step to first make it configurable; the default of 7 is not raised yet. Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'builtin/describe.c')
1 files changed, 5 insertions, 1 deletions
diff --git a/builtin/describe.c b/builtin/describe.c
index 342129f..9591596 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -21,7 +21,7 @@ static int debug; /* Display lots of verbose info */
static int all; /* Any valid ref can be used */
static int tags; /* Allow lightweight tags */
static int longformat;
-static int abbrev = DEFAULT_ABBREV;
+static int abbrev = -1; /* unspecified */
static int max_candidates = 10;
static struct hash_table names;
static int have_util;
@@ -420,7 +420,11 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
+ git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, options, describe_usage, 0);
+ if (abbrev < 0)
+ abbrev = DEFAULT_ABBREV;
if (max_candidates < 0)
max_candidates = 0;
else if (max_candidates > MAX_TAGS)