Re: [PATCH 2/3] prune_object_dir(): verify that path fits in the temporary buffer

From

Junio C Hamano <gitster@pobox.com>

Date

Dec 18, 2013, 20:07 UTC

Message-ID

<xmqqwqj1hqjd.fsf@gitster.dls.corp.google.com>

In-Reply-To

<20131218200043.GA10244@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

>> > +			prune_object(path->buf, sha1);
>> > +			path->len = baselen;
>> 
>> This is minor, but I prefer using strbuf_setlen() for this.
>
> Good catch. I do not think it is minor at all; my version is buggy.
> After the loop ends, path->len does not match the NUL in path->buf. That
> is OK if the next caller is strbuf-aware, but if it were to pass
> path->buf straight to a system call, that would be rather...confusing.

Will squash in the following.

 builtin/prune.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/builtin/prune.c b/builtin/prune.c
index 4ca8ec1..99f3f35 100644
--- a/builtin/prune.c
+++ b/builtin/prune.c
@@ -17,7 +17,7 @@ static int verbose;
 static unsigned long expire;
 static int show_progress = -1;
 
-static int prune_tmp_object(const char *fullpath)
+static int prune_tmp_file(const char *fullpath)
 {
 	struct stat st;
 	if (lstat(fullpath, &st))
@@ -78,13 +78,13 @@ static int prune_dir(int i, struct strbuf *path)
 
 			strbuf_addf(path, "/%s", de->d_name);
 			prune_object(path->buf, sha1);
-			path->len = baselen;
+			strbuf_setlen(&path, baselen);
 			continue;
 		}
 		if (!prefixcmp(de->d_name, "tmp_obj_")) {
 			strbuf_addf(path, "/%s", de->d_name);
-			prune_tmp_object(path->buf);
-			path->len = baselen;
+			prune_tmp_file(path->buf);
+			strbuf_setlen(&path, baselen);
 			continue;
 		}
 		fprintf(stderr, "bad sha1 file: %s/%s\n", path->buf, de->d_name);
@@ -108,7 +108,7 @@ static void prune_object_dir(const char *path)
 	for (i = 0; i < 256; i++) {
 		strbuf_addf(&buf, "%02x", i);
 		prune_dir(i, &buf);
-		buf.len = baselen;
+		strbuf_setlen(&buf, baselen);
 	}
 }
 
@@ -130,7 +130,7 @@ static void remove_temporary_files(const char *path)
 	}
 	while ((de = readdir(dir)) != NULL)
 		if (!prefixcmp(de->d_name, "tmp_"))
-			prune_tmp_object(mkpath("%s/%s", path, de->d_name));
+			prune_tmp_file(mkpath("%s/%s", path, de->d_name));
 	closedir(dir);
 }