[PATCH v8 4/6] verify-tag: prepare verify_tag for libification

[santiago@nyu.edu]

From: Santiago Torres <santiago@nyu.edu>

The current interface of verify_tag() resolves reference names to SHA1,
however, the plan is to make this functionality public and the current
interface is cumbersome for callers: they are expected to supply the
textual representation of a sha1/refname. In many cases, this requires
them to turn the sha1 to hex representation, just to be converted back
inside verify_tag.

Add a SHA1 parameter to use instead of the name parameter, and rename
the name parameter to "name_to_report" for reporting purposes only.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Santiago Torres <santiago@nyu.edu>
---
 builtin/verify-tag.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/builtin/verify-tag.c b/builtin/verify-tag.c
index fa26e40..a3d3a43 100644
--- a/builtin/verify-tag.c
+++ b/builtin/verify-tag.c
@@ -42,25 +42,28 @@ static int run_gpg_verify(const char *buf, unsigned long size, unsigned flags)
 	return ret;
 }
 
-static int verify_tag(const char *name, unsigned flags)
+static int verify_tag(const unsigned char *sha1, const char *name_to_report,
+			unsigned flags)
 {
 	enum object_type type;
-	unsigned char sha1[20];
 	char *buf;
 	unsigned long size;
 	int ret;
 
-	if (get_sha1(name, sha1))
-		return error("tag '%s' not found.", name);
-
 	type = sha1_object_info(sha1, NULL);
 	if (type != OBJ_TAG)
 		return error("%s: cannot verify a non-tag object of type %s.",
-				name, typename(type));
+				name_to_report ?
+				name_to_report :
+				find_unique_abbrev(sha1, DEFAULT_ABBREV),
+				typename(type));
 
 	buf = read_sha1_file(sha1, &type, &size);
 	if (!buf)
-		return error("%s: unable to read file.", name);
+		return error("%s: unable to read file.",
+				name_to_report ?
+				name_to_report :
+				find_unique_abbrev(sha1, DEFAULT_ABBREV));
 
 	ret = run_gpg_verify(buf, size, flags);
 
@@ -96,8 +99,13 @@ int cmd_verify_tag(int argc, const char **argv, const char *prefix)
 	if (verbose)
 		flags |= GPG_VERIFY_VERBOSE;
 
-	while (i < argc)
-		if (verify_tag(argv[i++], flags))
+	while (i < argc) {
+		unsigned char sha1[20];
+		const char *name = argv[i++];
+		if (get_sha1(name, sha1))
+			had_error = !!error("tag '%s' not found.", name);
+		else if (verify_tag(sha1, name, flags))
 			had_error = 1;
+	}
 	return had_error;
 }
-- 
2.8.0