[PATCH] git-describe: Die early if there are no possible descriptions
- From
Björn Steinbrink <b.steinbrink@gmx.de>
- Date
- Aug 5, 2009, 14:17 UTC
- Message-ID
- <20090805141740.GA16846@atjola.homenet>
If we found no refs that may be used for git-describe with the current options, then die early instead of pointlessly walking the whole history.
Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de> --- In git.git with all the tags dropped, this makes "git describe" go down from 0.244 to 0.003 seconds for me. This is especially noticeable with "git submodule" which calls describe with increasing levels of allowed refs to be matched. Without tags, this means that it walks the whole history in the submodule twice (first annotated, then plain tags), just to find out that it can't describe the thing anyway.
I'm not particularly sure about found_names actually counting the found names, it was just out of the thought that maybe the walking code could make use of it, but I didn't actually check that and ran out of time, so I'm sending this version, hoping that it doesn't suck too much.
builtin-describe.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/builtin-describe.c b/builtin-describe.c index 7a66298..cf802d1 100644 --- a/builtin-describe.c +++ b/builtin-describe.c @@ -20,6 +20,7 @@ static int tags; /* Allow lightweight tags */ static int longformat; static int abbrev = DEFAULT_ABBREV; static int max_candidates = 10; +static int found_names = 0; static const char *pattern; static int always; @@ -39,6 +40,8 @@ static void add_to_known_names(const char *path, const unsigned char *sha1) { struct commit_name *e = commit->util; + if (!e) + found_names++; if (!e || e->prio < prio) { size_t len = strlen(path)+1; free(e); @@ -195,6 +198,9 @@ static void describe(const char *arg, int last_one) for_each_ref(get_name, NULL); } + if (!found_names) + die("cannot describe '%s'", sha1_to_hex(sha1)); + n = cmit->util; if (n) { /*
-- 1.6.4.19.g42af.dirty