[PATCH v2 1/4] Move commit GPG signature verification to commit.c

@@ -1023,6 +1023,60 @@ free_return:
 	free(buf);
 }
 
+static struct {
+	char result;
+	const char *check;
+} signature_check[] = {
+	{ 'G', ": Good signature from " },
+	{ 'B', ": BAD signature from " },
+};
+
+static void parse_signature_lines(struct signature *sig)
+{
+	const char *buf = sig->gpg_output;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(signature_check); i++) {
+		const char *found = strstr(buf, signature_check[i].check);
+		const char *next;
+		if (!found)
+			continue;
+		sig->check_result = signature_check[i].result;
+		found += strlen(signature_check[i].check);
+		next = strchrnul(found, '\n');
+		sig->signer = xmemdupz(found, next - found);
+		break;
+	}
+}
+
+void check_commit_signature(const struct commit* commit, struct signature *sig)
+{
+	struct strbuf payload = STRBUF_INIT;
+	struct strbuf signature = STRBUF_INIT;
+	struct strbuf gpg_output = STRBUF_INIT;
+	int status;
+
+	sig->check_result = 'N';
+
+	if (parse_signed_commit(commit->object.sha1,
+				&payload, &signature) <= 0)
+		goto out;
+	status = verify_signed_buffer(payload.buf, payload.len,
+				      signature.buf, signature.len,
+				      &gpg_output);
+	if (status && !gpg_output.len)
+		goto out;
+	sig->gpg_output = strbuf_detach(&gpg_output, NULL);
+	parse_signature_lines(sig);
+
+ out:
+	strbuf_release(&gpg_output);
+	strbuf_release(&payload);
+	strbuf_release(&signature);
+}
+
+
+
 void append_merge_tag_headers(struct commit_list *parents,
 			      struct commit_extra_header ***tail)
 {

@@ -5,6 +5,7 @@
 #include "tree.h"
 #include "strbuf.h"
 #include "decorate.h"
+#include "gpg-interface.h"
 
 struct commit_list {
 	struct commit *item;

@@ -230,4 +231,12 @@ extern void print_commit_list(struct commit_list *list,
 			      const char *format_cur,
 			      const char *format_last);
 
+/*
+ * Check the signature of the given commit. The result of the check is stored in
+ * sig->check_result, 'G' for a good signature, 'B' for a bad signature and 'N'
+ * for no signature at all.
+ * This may allocate memory for sig->gpg_output and sig->signer.
+ */
+extern void check_commit_signature(const struct commit* commit, struct signature *sig);
+
 #endif /* COMMIT_H */

@@ -1,6 +1,12 @@
 #ifndef GPG_INTERFACE_H
 #define GPG_INTERFACE_H
 
+struct signature {
+	char *gpg_output;
+	char check_result; /* 0 (not checked), N (checked but no further result), G (good) or B (bad) */
+	char *signer;
+};
+
 extern int sign_buffer(struct strbuf *buffer, struct strbuf *signature, const char *signing_key);
 extern int verify_signed_buffer(const char *payload, size_t payload_size, const char *signature, size_t signature_size, struct strbuf *gpg_output);
 extern int git_gpg_config(const char *, const char *, void *);

@@ -756,12 +756,7 @@ struct format_commit_context {
 	const struct pretty_print_context *pretty_ctx;
 	unsigned commit_header_parsed:1;
 	unsigned commit_message_parsed:1;
-	unsigned commit_signature_parsed:1;
-	struct {
-		char *gpg_output;
-		char good_bad;
-		char *signer;
-	} signature;
+	struct signature signature;
 	char *message;
 	size_t width, indent1, indent2;
 

@@ -944,58 +939,6 @@ static void rewrap_message_tail(struct strbuf *sb,
 	c->indent2 = new_indent2;
 }
 
-static struct {
-	char result;
-	const char *check;
-} signature_check[] = {
-	{ 'G', ": Good signature from " },
-	{ 'B', ": BAD signature from " },
-};
-
-static void parse_signature_lines(struct format_commit_context *ctx)
-{
-	const char *buf = ctx->signature.gpg_output;
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(signature_check); i++) {
-		const char *found = strstr(buf, signature_check[i].check);
-		const char *next;
-		if (!found)
-			continue;
-		ctx->signature.good_bad = signature_check[i].result;
-		found += strlen(signature_check[i].check);
-		next = strchrnul(found, '\n');
-		ctx->signature.signer = xmemdupz(found, next - found);
-		break;
-	}
-}
-
-static void parse_commit_signature(struct format_commit_context *ctx)
-{
-	struct strbuf payload = STRBUF_INIT;
-	struct strbuf signature = STRBUF_INIT;
-	struct strbuf gpg_output = STRBUF_INIT;
-	int status;
-
-	ctx->commit_signature_parsed = 1;
-
-	if (parse_signed_commit(ctx->commit->object.sha1,
-				&payload, &signature) <= 0)
-		goto out;
-	status = verify_signed_buffer(payload.buf, payload.len,
-				      signature.buf, signature.len,
-				      &gpg_output);
-	if (status && !gpg_output.len)
-		goto out;
-	ctx->signature.gpg_output = strbuf_detach(&gpg_output, NULL);
-	parse_signature_lines(ctx);
-
- out:
-	strbuf_release(&gpg_output);
-	strbuf_release(&payload);
-	strbuf_release(&signature);
-}
-
 
 static int format_reflog_person(struct strbuf *sb,
 				char part,

@@ -1182,18 +1125,18 @@ static size_t format_commit_one(struct strbuf *sb, const char *placeholder,
 	}
 
 	if (placeholder[0] == 'G') {
-		if (!c->commit_signature_parsed)
-			parse_commit_signature(c);
+		if (!c->signature.check_result)
+			check_commit_signature(c->commit, &(c->signature));
 		switch (placeholder[1]) {
 		case 'G':
 			if (c->signature.gpg_output)
 				strbuf_addstr(sb, c->signature.gpg_output);
 			break;
 		case '?':
-			switch (c->signature.good_bad) {
+			switch (c->signature.check_result) {
 			case 'G':
 			case 'B':
-				strbuf_addch(sb, c->signature.good_bad);
+				strbuf_addch(sb, c->signature.check_result);
 			}
 			break;
 		case 'S':