refs: add option core.logAllRefUpdates = always

When core.logallrefupdates is true, we only create a new reflog for refs
that are under certain well-known hierarchies. The reason is that we
know that some hierarchies (like refs/tags) are not meant to change, and
that unknown hierarchies might not want reflogs at all (e.g., a
hypothetical refs/foo might be meant to change often and drop old
history immediately).

However, sometimes it is useful to override this decision and simply log
for all refs, because the safety and audit trail is more important than
the performance implications of keeping the log around.

This patch introduces a new "always" mode for the core.logallrefupdates
option which will log updates to everything under refs/, regardless
where in the hierarchy it is (we still will not log things like
ORIG_HEAD and FETCH_HEAD, which are known to be transient).

Based-on-patch-by: Jeff King <peff@peff.net>
Signed-off-by: Cornelius Weig <cornelius.weig@tngtech.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 10 insertions, 5 deletions

diff --git a/refs.c b/refs.c
index 9bd0bc177..cd36b64ed 100644
--- a/refs.c
+++ b/refs.c
@@ -638,12 +638,17 @@ int copy_reflog_msg(char *buf, const char *msg)
 
 int should_autocreate_reflog(const char *refname)
 {
-	if (!log_all_ref_updates)
+	switch (log_all_ref_updates) {
+	case LOG_REFS_ALWAYS:
+		return 1;
+	case LOG_REFS_NORMAL:
+		return starts_with(refname, "refs/heads/") ||
+			starts_with(refname, "refs/remotes/") ||
+			starts_with(refname, "refs/notes/") ||
+			!strcmp(refname, "HEAD");
+	default:
 		return 0;
-	return starts_with(refname, "refs/heads/") ||
-		starts_with(refname, "refs/remotes/") ||
-		starts_with(refname, "refs/notes/") ||
-		!strcmp(refname, "HEAD");
+	}
 }
 
 int is_branch(const char *refname)