convert "oidcmp() != 0" to "!oideq()"

This is the flip side of the previous two patches: checking
for a non-zero oidcmp() can be more strictly expressed as
inequality. Like those patches, we write "!= 0" in the
coccinelle transformation, which covers by isomorphism the
more common:

  if (oidcmp(E1, E2))

As with the previous two patches, this patch can be achieved
almost entirely by running "make coccicheck"; the only
differences are manual line-wrap fixes to match the original
code.

There is one thing to note for anybody replicating this,
though: coccinelle 1.0.4 seems to miss the case in
builtin/tag.c, even though it's basically the same as all
the others. Running with 1.0.7 does catch this, so
presumably it's just a coccinelle bug that was fixed in the
interim.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 3 insertions, 3 deletions

diff --git a/refs/files-backend.c b/refs/files-backend.c
index aa45f5317f..16ef9325e0 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -841,7 +841,7 @@ static int verify_lock(struct ref_store *ref_store, struct ref_lock *lock,
 			return 0;
 		}
 	}
-	if (old_oid && oidcmp(&lock->old_oid, old_oid)) {
+	if (old_oid && !oideq(&lock->old_oid, old_oid)) {
 		strbuf_addf(err, "ref '%s' is at %s but expected %s",
 			    lock->ref_name,
 			    oid_to_hex(&lock->old_oid),
diff --git a/refs/packed-backend.c b/refs/packed-backend.c
index d447a731da..74e2996e93 100644
--- a/refs/packed-backend.c
+++ b/refs/packed-backend.c
@@ -1160,7 +1160,7 @@ static int write_with_updates(struct packed_ref_store *refs,
 						    "reference already exists",
 						    update->refname);
 					goto error;
-				} else if (oidcmp(&update->old_oid, iter->oid)) {
+				} else if (!oideq(&update->old_oid, iter->oid)) {
 					strbuf_addf(err, "cannot update ref '%s': "
 						    "is at %s but expected %s",
 						    update->refname,
diff --git a/refs/ref-cache.c b/refs/ref-cache.c
index 9b110c8494..b7052f72e2 100644
--- a/refs/ref-cache.c
+++ b/refs/ref-cache.c
@@ -272,7 +272,7 @@ static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2
 		/* This is impossible by construction */
 		die("Reference directory conflict: %s", ref1->name);
 
-	if (oidcmp(&ref1->u.value.oid, &ref2->u.value.oid))
+	if (!oideq(&ref1->u.value.oid, &ref2->u.value.oid))
 		die("Duplicated ref, and SHA1s don't match: %s", ref1->name);
 
 	warning("Duplicated ref: %s", ref1->name);