[PATCH] Reuse previous annotation when overwriting a tag

From

Mike Hommey <mh@glandium.org>

Date

Nov 3, 2007, 09:31 UTC

Message-ID

<1194082273-19486-1-git-send-email-mh@glandium.org>

This is obviously only triggered for annotated tagging (-a or -s).

Signed-off-by: Mike Hommey <mh@glandium.org>
---
The write_annotation function could be made more generic and be used in
various different coming builtins such as git-commit. Also, it could be
used in show_reference() in builtin-tag.c.

 builtin-tag.c |   47 ++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/builtin-tag.c b/builtin-tag.c
index 66e5a58..cfd8017 100644
--- a/builtin-tag.c
+++ b/builtin-tag.c
@@ -247,9 +247,42 @@ static int git_tag_config(const char *var, const char *value)
 	return git_default_config(var, value);
 }
 
+static void write_annotation(int fd, const unsigned char *sha1)
+{
+	int i;
+	unsigned long size;
+	enum object_type type;
+	char *buf, *sp, *eol;
+	size_t len;
+
+	sp = buf = read_sha1_file(sha1, &type, &size);
+	if (!buf)
+		return;
+	if (!size || (type != OBJ_TAG)) {
+		free(buf);
+		return;
+	}
+	/* skip header */
+	while (sp + 1 < buf + size &&
+			!(sp[0] == '\n' && sp[1] == '\n'))
+		sp++;
+	/* strip the signature */
+	for (i = 0, sp += 2; sp < buf + size &&
+			prefixcmp(sp, PGP_SIGNATURE "\n");
+			i++) {
+		eol = memchr(sp, '\n', size - (sp - buf));
+		len = eol ? eol - sp : size - (sp - buf);
+		write_or_die(fd, sp, len + 1);
+		if (!eol)
+			break;
+		sp = eol + 1;
+	}
+	free(buf);
+}
+
 static void create_tag(const unsigned char *object, const char *tag,
 		       struct strbuf *buf, int message, int sign,
-			   unsigned char *result)
+			unsigned char *prev, unsigned char *result)
 {
 	enum object_type type;
 	char header_buf[1024];
@@ -282,6 +315,10 @@ static void create_tag(const unsigned char *object, const char *tag,
 		if (fd < 0)
 			die("could not create file '%s': %s",
 						path, strerror(errno));
+
+		if (prev)
+			write_annotation(fd, prev);
+
 		write_or_die(fd, tag_template, strlen(tag_template));
 		close(fd);
 
@@ -308,7 +345,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 {
 	struct strbuf buf;
 	unsigned char object[20], prev[20];
-	int annotate = 0, sign = 0, force = 0, lines = 0, message = 0;
+	int annotate = 0, sign = 0, force = 0, lines = 0,
+	    message = 0, existed = 0;
 	char ref[PATH_MAX];
 	const char *object_ref, *tag;
 	int i;
@@ -417,9 +455,12 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		hashclr(prev);
 	else if (!force)
 		die("tag '%s' already exists", tag);
+	else
+		existed = 1;
 
 	if (annotate)
-		create_tag(object, tag, &buf, message, sign, object);
+		create_tag(object, tag, &buf, message, sign,
+			   existed ? prev : NULL, object);
 
 	lock = lock_any_ref_for_update(ref, prev, 0);
 	if (!lock)

-- 
1.5.3.5