reflog expire: use "switch" over enum values

Change code added in 03cb91b18cc (reflog --expire-unreachable: special
case entries in "HEAD" reflog, 2010-04-09) to use a "switch" statement
with an exhaustive list of "case" statements instead of doing numeric
comparisons against the enum labels.

Now we won't assume that "x != UE_ALWAYS" means "(x == UE_HEAD || x ||
UE_NORMAL)". That assumption is true now, but we'd introduce subtle
bugs here if that were to change, now the compiler will notice and
error out on such errors.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/reflog.c b/builtin/reflog.c
index 27851c6efb769ea4139567a01348ec9d2a509449..8d05660e644a615a6253546bd82dfde59924ca71 100644 (file)
--- a/builtin/reflog.c
+++ b/builtin/reflog.c
@@ -303,10 +303,15 @@ static int should_expire_reflog_ent(struct object_id *ooid, struct object_id *no
                return 1;
 
        if (timestamp < cb->cmd.expire_unreachable) {
-               if (cb->unreachable_expire_kind == UE_ALWAYS)
-                       return 1;
-               if (unreachable(cb, old_commit, ooid) || unreachable(cb, new_commit, noid))
+               switch (cb->unreachable_expire_kind) {
+               case UE_ALWAYS:
                        return 1;
+               case UE_NORMAL:
+               case UE_HEAD:
+                       if (unreachable(cb, old_commit, ooid) || unreachable(cb, new_commit, noid))
+                               return 1;
+                       break;
+               }
        }
 
        if (cb->cmd.recno && --(cb->cmd.recno) == 0)
@@ -348,6 +353,7 @@ static void reflog_expiry_prepare(const char *refname,
                                  void *cb_data)
 {
        struct expire_reflog_policy_cb *cb = cb_data;
+       struct commit_list *elem;
 
        if (!cb->cmd.expire_unreachable || is_head(refname)) {
                cb->unreachable_expire_kind = UE_HEAD;
@@ -363,34 +369,37 @@ static void reflog_expiry_prepare(const char *refname,
        if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
                cb->unreachable_expire_kind = UE_ALWAYS;
 
-       if (cb->unreachable_expire_kind != UE_ALWAYS) {
-               if (cb->unreachable_expire_kind == UE_HEAD) {
-                       struct commit_list *elem;
-
-                       for_each_ref(push_tip_to_list, &cb->tips);
-                       for (elem = cb->tips; elem; elem = elem->next)
-                               commit_list_insert(elem->item, &cb->mark_list);
-               } else {
-                       commit_list_insert(cb->tip_commit, &cb->mark_list);
-               }
-               cb->mark_limit = cb->cmd.expire_total;
-               mark_reachable(cb);
+       switch (cb->unreachable_expire_kind) {
+       case UE_ALWAYS:
+               return;
+       case UE_HEAD:
+               for_each_ref(push_tip_to_list, &cb->tips);
+               for (elem = cb->tips; elem; elem = elem->next)
+                       commit_list_insert(elem->item, &cb->mark_list);
+               break;
+       case UE_NORMAL:
+               commit_list_insert(cb->tip_commit, &cb->mark_list);
        }
+       cb->mark_limit = cb->cmd.expire_total;
+       mark_reachable(cb);
 }
 
 static void reflog_expiry_cleanup(void *cb_data)
 {
        struct expire_reflog_policy_cb *cb = cb_data;
+       struct commit_list *elem;
 
-       if (cb->unreachable_expire_kind != UE_ALWAYS) {
-               if (cb->unreachable_expire_kind == UE_HEAD) {
-                       struct commit_list *elem;
-                       for (elem = cb->tips; elem; elem = elem->next)
-                               clear_commit_marks(elem->item, REACHABLE);
-                       free_commit_list(cb->tips);
-               } else {
-                       clear_commit_marks(cb->tip_commit, REACHABLE);
-               }
+       switch (cb->unreachable_expire_kind) {
+       case UE_ALWAYS:
+               return;
+       case UE_HEAD:
+               for (elem = cb->tips; elem; elem = elem->next)
+                       clear_commit_marks(elem->item, REACHABLE);
+               free_commit_list(cb->tips);
+               break;
+       case UE_NORMAL:
+               clear_commit_marks(cb->tip_commit, REACHABLE);
+               break;
        }
 }