strbuf: add strbuf_vaddf

In a variable-args function, the code for writing into a strbuf is
non-trivial. We ended up cutting and pasting it in several places
because there was no vprintf-style function for strbufs (which in turn
was held up by a lack of va_copy).

Now that we have a fallback va_copy, we can add strbuf_vaddf, the
strbuf equivalent of vsprintf. And we can clean up the cut and paste
mess.

Signed-off-by: Jeff King <peff@peff.net>
Improved-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 13 deletions

diff --git a/fsck.c b/fsck.c
index 3d05d4a794..6f266c1ea4 100644
--- a/fsck.c
+++ b/fsck.c
@@ -347,26 +347,14 @@ int fsck_object(struct object *obj, int strict, fsck_error error_func)
 int fsck_error_function(struct object *obj, int type, const char *fmt, ...)
 {
 	va_list ap;
-	int len;
 	struct strbuf sb = STRBUF_INIT;
 
 	strbuf_addf(&sb, "object %s:", obj->sha1?sha1_to_hex(obj->sha1):"(null)");
 
 	va_start(ap, fmt);
-	len = vsnprintf(sb.buf + sb.len, strbuf_avail(&sb), fmt, ap);
+	strbuf_vaddf(&sb, fmt, ap);
 	va_end(ap);
 
-	if (len < 0)
-		len = 0;
-	if (len >= strbuf_avail(&sb)) {
-		strbuf_grow(&sb, len + 2);
-		va_start(ap, fmt);
-		len = vsnprintf(sb.buf + sb.len, strbuf_avail(&sb), fmt, ap);
-		va_end(ap);
-		if (len >= strbuf_avail(&sb))
-			die("this should not happen, your snprintf is broken");
-	}
-
 	error("%s", sb.buf);
 	strbuf_release(&sb);
 	return 1;