sha1_file: remove static strbuf from sha1_file_name()

Using a static buffer in sha1_file_name() is error prone
and the performance improvements it gives are not needed
in many of the callers.

So let's get rid of this static buffer and, if necessary
or helpful, let's use one in the caller.

Suggested-by: Jeff Hostetler <git@jeffhostetler.com>
Helped-by: Kevin Daudt <me@ikke.info>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 25 insertions, 13 deletions

diff --git a/sha1_file.c b/sha1_file.c
index 36f8545..740dda4 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -251,15 +251,11 @@ static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1)
 	}
 }
 
-const char *sha1_file_name(const unsigned char *sha1)
+void sha1_file_name(struct strbuf *buf, const unsigned char *sha1)
 {
-	static struct strbuf buf = STRBUF_INIT;
-
-	strbuf_reset(&buf);
-	strbuf_addf(&buf, "%s/", get_object_directory());
+	strbuf_addf(buf, "%s/", get_object_directory());
 
-	fill_sha1_path(&buf, sha1);
-	return buf.buf;
+	fill_sha1_path(buf, sha1);
 }
 
 struct strbuf *alt_scratch_buf(struct alternate_object_database *alt)
@@ -643,7 +639,12 @@ int check_and_freshen_file(const char *fn, int freshen)
 
 static int check_and_freshen_local(const unsigned char *sha1, int freshen)
 {
-	return check_and_freshen_file(sha1_file_name(sha1), freshen);
+	static struct strbuf buf = STRBUF_INIT;
+
+	strbuf_reset(&buf);
+	sha1_file_name(&buf, sha1);
+
+	return check_and_freshen_file(buf.buf, freshen);
 }
 
 static int check_and_freshen_nonlocal(const unsigned char *sha1, int freshen)
@@ -799,8 +800,12 @@ static int stat_sha1_file(const unsigned char *sha1, struct stat *st,
 			  const char **path)
 {
 	struct alternate_object_database *alt;
+	static struct strbuf buf = STRBUF_INIT;
+
+	strbuf_reset(&buf);
+	sha1_file_name(&buf, sha1);
+	*path = buf.buf;
 
-	*path = sha1_file_name(sha1);
 	if (!lstat(*path, st))
 		return 0;
 
@@ -824,8 +829,12 @@ static int open_sha1_file(const unsigned char *sha1, const char **path)
 	int fd;
 	struct alternate_object_database *alt;
 	int most_interesting_errno;
+	static struct strbuf buf = STRBUF_INIT;
+
+	strbuf_reset(&buf);
+	sha1_file_name(&buf, sha1);
+	*path = buf.buf;
 
-	*path = sha1_file_name(sha1);
 	fd = git_open(*path);
 	if (fd >= 0)
 		return fd;
@@ -1487,9 +1496,12 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
 	git_SHA_CTX c;
 	unsigned char parano_sha1[20];
 	static struct strbuf tmp_file = STRBUF_INIT;
-	const char *filename = sha1_file_name(sha1);
+	static struct strbuf filename = STRBUF_INIT;
+
+	strbuf_reset(&filename);
+	sha1_file_name(&filename, sha1);
 
-	fd = create_tmpfile(&tmp_file, filename);
+	fd = create_tmpfile(&tmp_file, filename.buf);
 	if (fd < 0) {
 		if (errno == EACCES)
 			return error("insufficient permission for adding an object to repository database %s", get_object_directory());
@@ -1542,7 +1554,7 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
 			warning_errno("failed utime() on %s", tmp_file.buf);
 	}
 
-	return finalize_object_file(tmp_file.buf, filename);
+	return finalize_object_file(tmp_file.buf, filename.buf);
 }
 
 static int freshen_loose_object(const unsigned char *sha1)