Add a test to check for issues with deeply nested objects, which can cause problems due to stack recursion.

tests/test_deep_nesting.c

@@ -0,0 +1,84 @@
+#ifdef NDEBUG
+#undef NDEBUG
+#endif
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+
+#include "config.h"
+
+#include "json.h"
+
+#define NESTING_DEPTH 100000
+
+static char *generate_json_string(void);
+static char *generate_json_string()
+{
+	char *str;
+	int depth = NESTING_DEPTH;
+	str = malloc(depth * 2 + 1);
+	memset(str, '[', depth);
+	memset(str + depth, ']', depth);
+	str[depth * 2] = '\0';
+	return str;
+}
+
+static void test_deep_nesting_put(const char *str);
+static void test_deep_nesting_put(const char *str)
+{
+	json_object *my_array;
+
+	struct json_tokener *tok = json_tokener_new_ex(NESTING_DEPTH);
+	my_array = json_tokener_parse_ex(tok, str, strlen(str) + 1);
+	printf("Parsed depth %d string to json_object: %s\n", NESTING_DEPTH, (my_array == NULL) ? "NO" : "yes");
+
+	json_object_put(my_array);
+	printf("Freed json_object\n");
+
+	json_tokener_free(tok);
+}
+
+static void test_deep_nesting_tostring(const char *str);
+static void test_deep_nesting_tostring(const char *str)
+{
+	json_object *my_array;
+
+	struct json_tokener *tok = json_tokener_new_ex(NESTING_DEPTH);
+	my_array = json_tokener_parse_ex(tok, str, strlen(str) + 1);
+	printf("Parsed depth %d string to json_object: %s\n", NESTING_DEPTH, (my_array == NULL) ? "NO" : "yes");
+
+	const char *res = json_object_to_json_string_ext(my_array, JSON_C_TO_STRING_PLAIN);
+	printf("Serialized to string of length %ld\n", (long)strlen(res));
+	json_object_put(my_array);
+	printf("Freed json_object\n");
+
+	json_tokener_free(tok);
+}
+
+int main(int argc, char **argv)
+{
+	char *str;	
+#ifdef HAVE_SETRLIMIT
+	struct rlimit rl;
+	rl.rlim_cur = 2048;
+	rl.rlim_max = 2048;
+	setrlimit(RLIMIT_STACK, &rl);
+#endif
+
+	str = generate_json_string();
+
+	MC_SET_DEBUG(1);
+
+	test_deep_nesting_put(str);
+
+	if (0) // TODO: make json_object_to_json_string non-recursive
+		test_deep_nesting_tostring(str);
+
+	free(str);
+
+	return EXIT_SUCCESS;
+}