drop strcpy in favor of raw sha1_to_hex

In some cases where we strcpy() the result of sha1_to_hex(),
there's no need; the result goes directly into a printf
statement, and we can simply pass the return value from
sha1_to_hex() directly.

When this code was originally written, sha1_to_hex used a
single buffer, and it was not safe to use it twice within a
single expression. That changed as of dcb3450f (sha1_to_hex()
usage cleanup, 2006-05-03), but this code was never updated.
History-dug-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

http-push.c

@@ -1856,7 +1856,6 @@ int main(int argc, char **argv)
 
 	new_refs = 0;
 	for (ref = remote_refs; ref; ref = ref->next) {
-		char old_hex[60], *new_hex;
 		struct argv_array commit_argv = ARGV_ARRAY_INIT;
 
 		if (!ref->peer_ref)
@@ -1911,13 +1910,12 @@ int main(int argc, char **argv)
 		}
 		hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
 		new_refs++;
-		strcpy(old_hex, sha1_to_hex(ref->old_sha1));
-		new_hex = sha1_to_hex(ref->new_sha1);
 
 		fprintf(stderr, "updating '%s'", ref->name);
 		if (strcmp(ref->name, ref->peer_ref->name))
 			fprintf(stderr, " using '%s'", ref->peer_ref->name);
-		fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
+		fprintf(stderr, "\n  from %s\n  to   %s\n",
+			sha1_to_hex(ref->old_sha1), sha1_to_hex(ref->new_sha1));
 		if (dry_run) {
 			if (helper_status)
 				printf("ok %s\n", ref->name);

walker.c

@@ -17,10 +17,9 @@ void walker_say(struct walker *walker, const char *fmt, const char *hex)
 
 static void report_missing(const struct object *obj)
 {
-	char missing_hex[41];
-	strcpy(missing_hex, sha1_to_hex(obj->sha1));
 	fprintf(stderr, "Cannot obtain needed %s %s\n",
-		obj->type ? typename(obj->type): "object", missing_hex);
+		obj->type ? typename(obj->type): "object",
+		sha1_to_hex(obj->sha1));
 	if (!is_null_sha1(current_commit_sha1))
 		fprintf(stderr, "while processing commit %s.\n",
 			sha1_to_hex(current_commit_sha1));