Re: [PATCH 07/17] commit: increase commit message buffer size
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jul 9, 2018, 17:45 UTC
- Message-ID
- <xmqqva9oe20y.fsf@gitster-ct.c.googlers.com>
- In-Reply-To
- <4eb44f33-ac9c-7ce2-0e53-ec6fcb4560fd@gmail.com>
Derrick Stolee <stolee@gmail.com> writes:
Show 25 quoted lines
> On 7/8/2018 7:36 PM, brian m. carlson wrote: >> 100 bytes is not sufficient to ensure we can write a commit message >> buffer when using a 32-byte hash algorithm. Increase the buffer size to >> ensure we have sufficient space. >> >> Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> >> --- >> refs/files-backend.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/refs/files-backend.c b/refs/files-backend.c >> index a9a066dcfb..252f835bae 100644 >> --- a/refs/files-backend.c >> +++ b/refs/files-backend.c >> @@ -1587,7 +1587,7 @@ static int log_ref_write_fd(int fd, const struct object_id *old_oid, >> char *logrec; >> msglen = msg ? strlen(msg) : 0; >> - maxlen = strlen(committer) + msglen + 100; >> + maxlen = strlen(committer) + msglen + 200; >> logrec = xmalloc(maxlen); >> len = xsnprintf(logrec, maxlen, "%s %s %s\n", >> oid_to_hex(old_oid), > > nit: 100 is not enough anymore, but wasn't a very descriptive > value. 200 may be enough now, but I'm not sure why.
As Brandon alludes to downthread, we probably should use strbuf for things like this these days, so a preliminary clean-up to do so is probably a welcome change to sneak in and rebase this series on top of.
"%s %s %s\n" with old and new commit object name and the message will be "2 * len(hash_in_hex) + 4" bytes long (counting the three whitespaces and the terminating NUL), and Shawn's original in 6de08ae6 ("Log ref updates to logs/refs/<ref>", 2006-05-17) actually computed this one as "strlen(...) + 2*40+4".
100 was merely me being sloppier than Shawn at 8ac65937 ("Make sure we do not write bogus reflog entries.", 2007-01-26), preferring being sufficient over not wasting even a single byte.