[RFC WIP PATCH 1/3] tag: factor out tag reading from write_tag_body()
To
git@vger.kernel.org
Cc
kernel-usp@googlegroups.com
rcdailey.lists@gmail.com
me@ttaylorr.com
peff@peff.net
matheus.bernardino@usp.br
Bárbara Fernandes
From
Lucas Oshiro
See Also
Prev
Date
2019-10-08 18:47:25 UTC
Improve code readability by moving tag reading to a new function called
get_tag_body, which will be used in the implementation of the git tag
--amend functionality.

Add warning in write_tag_body() in case the tag body is not successfully
recovered.

Co-authored-by: Bárbara Fernandes <barbara.dcf@gmail.com>
Signed-off-by: Bárbara Fernandes <barbara.dcf@gmail.com>
Signed-off-by: Lucas Oshiro <lucasseikioshiro@gmail.com>
Helped-by: Matheus Tavares <matheus.bernardino@usp.br>
---
 builtin/tag.c | 42 ++++++++++++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 8 deletions(-)

diff --git a/builtin/tag.c b/builtin/tag.c
index e0a4c25382..e1e3549af9 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -170,26 +170,52 @@ static int git_tag_config(const char *var, const char *value, void *cb)
 	return git_color_default_config(var, value, cb);
 }
 
-static void write_tag_body(int fd, const struct object_id *oid)
+/* 
+ * Returns the tag body of the given oid or NULL, in case of error. If size is
+ * not NULL it is assigned the body size in bytes (excluding the '\0').
+ */
+static char *get_tag_body(const struct object_id *oid, size_t *size) 
 {
-	unsigned long size;
+	unsigned long buf_size;
 	enum object_type type;
-	char *buf, *sp;
+	char *buf, *sp, *tag_body;
+	size_t tag_body_size, signature_offset;
 
-	buf = read_object_file(oid, &type, &size);
+	buf = read_object_file(oid, &type, &buf_size);
 	if (!buf)
-		return;
+		return NULL;
 	/* skip header */
 	sp = strstr(buf, "\n\n");
 
-	if (!sp || !size || type != OBJ_TAG) {
+	if (!sp || !buf_size || type != OBJ_TAG) {
 		free(buf);
-		return;
+		return NULL;
 	}
 	sp += 2; /* skip the 2 LFs */
-	write_or_die(fd, sp, parse_signature(sp, buf + size - sp));
+	signature_offset = parse_signature(sp, buf + buf_size - sp);
+	sp[signature_offset] = '\0';
 
+	/* detach sp from buf */
+	tag_body_size = strlen(sp) + 1;
+	tag_body = xmalloc(tag_body_size);
+	xsnprintf(tag_body, tag_body_size, "%s", sp);
 	free(buf);
+	if (size)
+		*size = tag_body_size - 1; /* exclude '\0' */
+	return tag_body;
+}
+
+static void write_tag_body(int fd, const struct object_id *oid)
+{
+	size_t size;
+	const char *tag_body = get_tag_body(oid, &size);
+
+	if (!tag_body) {
+		warning("failed to get tag body for %s", oid->hash);
+		return;
+	}
+	printf("tag_body: <%s>\n", tag_body);
+	write_or_die(fd, tag_body, size);
 }
 
 static int build_tag_object(struct strbuf *buf, int sign, struct object_id *result)
-- 
2.23.0