reftable/stack: handle allocation failures in reftable_new_stack()

Handle allocation failures in `reftable_new_stack()`.

Signed-off-by: Patrick Steinhardt <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: pks-t

reftable/stack.c

@@ -56,10 +56,16 @@ static int reftable_fd_flush(void *arg)
 int reftable_new_stack(struct reftable_stack **dest, const char *dir,
 		       const struct reftable_write_options *_opts)
 {
-	struct reftable_stack *p = reftable_calloc(1, sizeof(*p));
 	struct strbuf list_file_name = STRBUF_INIT;
-	struct reftable_write_options opts = {0};
-	int err = 0;
+	struct reftable_write_options opts = { 0 };
+	struct reftable_stack *p;
+	int err;
+
+	p = reftable_calloc(1, sizeof(*p));
+	if (!p) {
+		err = REFTABLE_OUT_OF_MEMORY_ERROR;
+		goto out;
+	}
 
 	if (_opts)
 		opts = *_opts;
@@ -74,15 +80,23 @@ int reftable_new_stack(struct reftable_stack **dest, const char *dir,
 
 	p->list_file = strbuf_detach(&list_file_name, NULL);
 	p->list_fd = -1;
-	p->reftable_dir = xstrdup(dir);
 	p->opts = opts;
+	p->reftable_dir = reftable_strdup(dir);
+	if (!p->reftable_dir) {
+		err = REFTABLE_OUT_OF_MEMORY_ERROR;
+		goto out;
+	}
 
 	err = reftable_stack_reload_maybe_reuse(p, 1);
-	if (err < 0) {
+	if (err < 0)
+		goto out;
+
+	*dest = p;
+	err = 0;
+
+out:
+	if (err < 0)
 		reftable_stack_destroy(p);
-	} else {
-		*dest = p;
-	}
 	return err;
 }
 
@@ -171,6 +185,10 @@ void reftable_stack_destroy(struct reftable_stack *st)
 {
 	char **names = NULL;
 	int err = 0;
+
+	if (!st)
+		return;
+
 	if (st->merged) {
 		reftable_merged_table_free(st->merged);
 		st->merged = NULL;