wrapper.c: add a new function unlink_or_msg

This behaves like unlink_or_warn except that on failure it writes the message
to its 'err' argument, which the caller can display in an appropriate way or
ignore.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/wrapper.c b/wrapper.c
index 8d4be66e66..007ec0d8ea 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -475,6 +475,20 @@ static int warn_if_unremovable(const char *op, const char *file, int rc)
 	return rc;
 }
 
+int unlink_or_msg(const char *file, struct strbuf *err)
+{
+	int rc = unlink(file);
+
+	assert(err);
+
+	if (!rc || errno == ENOENT)
+		return 0;
+
+	strbuf_addf(err, "unable to unlink %s: %s",
+		    file, strerror(errno));
+	return -1;
+}
+
 int unlink_or_warn(const char *file)
 {
 	return warn_if_unremovable("unlink", file, unlink(file));