Revert "gpg-interface: prefer check_signature() for GPG verification"

This reverts commit 72b006f4bfd30b7c5037c163efaf279ab65bea9c, which
breaks the end-user experience when merging a signed tag without
having the public key.  We should report "can't check because we
have no public key", but the code with this change claimed that
there was no signature.

1 files changed, 14 insertions, 16 deletions

diff --git a/log-tree.c b/log-tree.c
index aa6b038..1e56df6 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -448,22 +448,22 @@ static void show_signature(struct rev_info *opt, struct commit *commit)
 {
 	struct strbuf payload = STRBUF_INIT;
 	struct strbuf signature = STRBUF_INIT;
-	struct signature_check sigc = { 0 };
+	struct strbuf gpg_output = STRBUF_INIT;
 	int status;
 
 	if (parse_signed_commit(commit, &payload, &signature) <= 0)
 		goto out;
 
-	status = check_signature(payload.buf, payload.len, signature.buf,
-				 signature.len, &sigc);
-	if (status && sigc.result == 'N')
-		show_sig_lines(opt, status, "No signature\n");
-	else {
-		show_sig_lines(opt, status, sigc.gpg_output);
-		signature_check_clear(&sigc);
-	}
+	status = verify_signed_buffer(payload.buf, payload.len,
+				      signature.buf, signature.len,
+				      &gpg_output, NULL);
+	if (status && !gpg_output.len)
+		strbuf_addstr(&gpg_output, "No signature\n");
+
+	show_sig_lines(opt, status, gpg_output.buf);
 
  out:
+	strbuf_release(&gpg_output);
 	strbuf_release(&payload);
 	strbuf_release(&signature);
 }
@@ -496,7 +496,6 @@ static int show_one_mergetag(struct commit *commit,
 	struct object_id oid;
 	struct tag *tag;
 	struct strbuf verify_message;
-	struct signature_check sigc = { 0 };
 	int status, nth;
 	size_t payload_size, gpg_message_offset;
 
@@ -525,13 +524,12 @@ static int show_one_mergetag(struct commit *commit,
 	status = -1;
 	if (extra->len > payload_size) {
 		/* could have a good signature */
-		if (!check_signature(extra->value, payload_size,
-				     extra->value + payload_size,
-				     extra->len - payload_size, &sigc)) {
-			strbuf_addstr(&verify_message, sigc.gpg_output);
-			signature_check_clear(&sigc);
+		if (!verify_signed_buffer(extra->value, payload_size,
+					  extra->value + payload_size,
+					  extra->len - payload_size,
+					  &verify_message, NULL))
 			status = 0; /* good */
-		} else if (verify_message.len <= gpg_message_offset)
+		else if (verify_message.len <= gpg_message_offset)
 			strbuf_addstr(&verify_message, "No signature\n");
 		/* otherwise we couldn't verify, which is shown as bad */
 	}