builtin/annotate: fix leaking args vector

We're leaking the args vector in git-annotate(1) because we never clear
it. Fixing it isn't as easy as calling `strvec_clear()` though because
calling `cmd_blame()` will cause the underlying array to be modified.
Instead, we also need to pass a shallow copy of the argv array to the
function.

Do so to plug the memory leaks.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/annotate.c

@@ -15,13 +15,23 @@ int cmd_annotate(int argc,
 		 struct repository *repo UNUSED)
 {
 	struct strvec args = STRVEC_INIT;
-	int i;
+	const char **args_copy;
+	int ret;
 
 	strvec_pushl(&args, "annotate", "-c", NULL);
-
+	for (int i = 1; i < argc; i++)
-	for (i = 1; i < argc; i++) {
 		strvec_push(&args, argv[i]);
-	}
 
-	return cmd_blame(args.nr, args.v, prefix, the_repository);
+	/*
+	 * `cmd_blame()` ends up modifying the array, which causes memory leaks
+	 * if we didn't copy the array here.
+	 */
+	CALLOC_ARRAY(args_copy, args.nr + 1);
+	COPY_ARRAY(args_copy, args.v, args.nr);
+
+	ret = cmd_blame(args.nr, args_copy, prefix, the_repository);
+
+	strvec_clear(&args);
+	free(args_copy);
+	return ret;
 }

t/t8001-annotate.sh

@@ -5,6 +5,7 @@ GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
 TEST_CREATE_REPO_NO_TEMPLATE=1
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 PROG='git annotate'