strings: add more tests

cheney_c89: fix memory leak errors

1 files changed, 25 insertions, 9 deletions

diff --git a/examples/string/uns_string.c b/examples/string/uns_string.c
index e510fcf..219df89 100644
--- a/examples/string/uns_string.c
+++ b/examples/string/uns_string.c
@@ -70,27 +70,43 @@ char *uns_string_ptr(struct uns_gc *gc, struct uns_root_list *root)
 
 void uns_string_alloc(struct uns_gc *gc, struct uns_root_list *root, size_t start_len)
 {
+	unsigned char *p;
 	root->p = gc->alloc_record(gc, NUMBER_OF_IND);
 
-	gc->record_set_ptr(root->p, ALLEN_IND, gc->alloc(gc, sizeof(size_t)));
+	/* The following is incorrect:
+	 *   gc->record_set_ptr(root->p, ALLEN_IND, gc->alloc(gc, sizeof(size_t)));
+	 * This is because gc->alloc() can cause a collection, invalidating root->p,
+	 * but root->p may have already been put on the stack.
+	 */
+
+	p = gc->alloc(gc, sizeof(size_t));
+	gc->record_set_ptr(root->p, ALLEN_IND, p);
 	set_allen(gc, root, start_len);
 
-	gc->record_set_ptr(root->p, LEN_IND, gc->alloc(gc, sizeof(size_t)));
+	p = gc->alloc(gc, sizeof(size_t));
+	gc->record_set_ptr(root->p, LEN_IND, p);
 	set_len(gc, root, 0);
 
-	gc->record_set_ptr(root->p, BYTES_IND, gc->alloc(gc, start_len));
+	p = gc->alloc(gc, start_len);
+	gc->record_set_ptr(root->p, BYTES_IND, p);
 }
 
 void uns_string_resize(struct uns_gc *gc, struct uns_root_list *root, size_t newlen)
 {
-	char *tmp;
+	struct uns_root_list tmp_new = {0};
+	size_t old_len = uns_string_len(gc, root);
+
+	uns_root_add(gc, &tmp_new);
+	uns_string_alloc(gc, &tmp_new, newlen);
 
-	tmp = gc->alloc(gc, newlen);
-	set_allen(gc, root, newlen);
+	if (newlen <= old_len)
+		set_len(gc, &tmp_new, newlen);
+	else
+		set_len(gc, &tmp_new, old_len);
 
-	if (newlen <= uns_string_len(gc, root))
-		set_len(gc, root, newlen);
-	memcpy(tmp, uns_string_ptr(gc, root), uns_string_len(gc, root));
+	memcpy(uns_string_ptr(gc, &tmp_new), uns_string_ptr(gc, root), uns_string_len(gc, root));
+	root->p = tmp_new.p;
+	uns_root_remove(gc, &tmp_new);
 }
 
 void uns_string_ensure(struct uns_gc *gc, struct uns_root_list *root, size_t extent)