Merge branch 'json_deep_copy' of https://github.com/commodo/json-c into commodo-json_deep_copy

.gitignore

@@ -25,6 +25,7 @@
 /tests/test_cast
 /tests/test_charcase
 /tests/test_compare
+/tests/test_deep_copy
 /tests/test_double_serializer
 /tests/test_float
 /tests/test_int_add

json_object.c

@@ -1299,3 +1299,106 @@ int json_object_equal(struct json_object* jso1, struct json_object* jso2)
 	return 0;
 }
 
+static int json_object_copy_serializer_data(struct json_object *src, struct json_object *dst)
+{
+	/* FIXME: this is shared between copies ; maybe add a `_user_copy` cb here */
+	dst->_userdata = src->_userdata;
+	dst->_to_json_string = src->_to_json_string;
+	dst->_user_delete = src->_user_delete;
+	return 0;
+}
+
+static int json_object_deep_copy_recursive(struct json_object *src, struct json_object **dst)
+{
+	struct json_object *jso = NULL;
+	struct json_object_iter iter;
+	size_t i;
+
+	if (!src || !dst) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	switch (src->o_type) {
+		case json_type_boolean:
+			*dst = json_object_new_boolean(src->o.c_boolean);
+			break;
+
+		case json_type_double:
+			*dst = json_object_new_double(src->o.c_double);
+			break;
+
+		case json_type_int:
+			*dst = json_object_new_int64(src->o.c_int64);
+			break;
+
+		case json_type_string:
+			*dst = json_object_new_string(get_string_component(src));
+			break;
+
+		case json_type_object:
+			*dst = json_object_new_object();
+			if (!*dst) {
+				errno = ENOMEM;
+				return -1;
+			}
+			json_object_object_foreachC(src, iter) {
+				/* This handles the `json_type_null` case */
+				if (!iter.val)
+					jso = NULL;
+				else if (json_object_deep_copy_recursive(iter.val, &jso) < 0)
+					return -1;
+				if (json_object_object_add(*dst, iter.key, jso) < 0)
+					return -1;
+			}
+			break;
+
+		case json_type_array:
+			*dst = json_object_new_array();
+			if (!*dst) {
+				errno = ENOMEM;
+				return -1;
+			}
+			for (i = 0; i < json_object_array_length(src); i++) {
+				struct json_object *jso1 = json_object_array_get_idx(src, i);
+				/* This handles the `json_type_null` case */
+				if (!jso1)
+					jso = NULL;
+				else if (json_object_deep_copy_recursive(jso1, &jso) < 0)
+						return -1;
+				if (json_object_array_add(*dst, jso) < 0)
+					return -1;
+			}
+			break;
+
+		default:
+			errno = EINVAL;
+			return -1;
+	};
+
+	/* errno should be set by the function that faulted */
+	if (!*dst)
+		return -1;
+
+	return json_object_copy_serializer_data(src, *dst);
+}
+
+int json_object_deep_copy(struct json_object *src, struct json_object **dst)
+{
+	int rc;
+
+	/* Check if arguments are sane ; *dst must not point to a non-NULL object */
+	if (!src || !dst || *dst) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	rc = json_object_deep_copy_recursive(src, dst);
+	if (rc < 0) {
+		json_object_put(*dst);
+		*dst = NULL;
+	}
+
+	return rc;
+}
+

json_object.h

@@ -963,6 +963,24 @@ JSON_EXPORT int json_object_set_string_len(json_object* obj, const char* new_val
 JSON_EXPORT int json_object_equal(struct json_object *obj1,
 			     struct json_object *obj2);
 
+/**
+ * Copy the contents of the JSON object.
+ * The destination object must be initialized to NULL,
+ * to make sure this function won't overwrite an existing JSON object.
+ *
+ * This does roughly the same thing as
+ * `json_tokener_parse(json_object_get_string(src))`.
+ *
+ * @param src source JSON object whose contents will be copied
+ * @param dst pointer to the destination object where the contents of `src`;
+ *            make sure this pointer is initialized to NULL
+ *
+ * @returns 0 if the copy went well, -1 if an error occured during copy
+ *          or if the destination pointer is non-NULL
+ */
+
+extern int json_object_deep_copy(struct json_object *src, struct json_object **dst);
+
 #ifdef __cplusplus
 }
 #endif

tests/Makefile.am

@@ -13,6 +13,7 @@ TESTS+= test2.test
 TESTS+= test4.test
 TESTS+= testReplaceExisting.test
 TESTS+= test_parse_int64.test
+TESTS+= test_deep_copy.test
 TESTS+= test_null.test
 TESTS+= test_cast.test
 TESTS+= test_double_serializer.test

tests/test_deep_copy.c

@@ -0,0 +1,175 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+#include <time.h>
+
+#include "json.h"
+
+static const char *json_str1 = 
+"{"
+"    \"glossary\": {"
+"        \"title\": \"example glossary\","
+"        \"GlossDiv\": {"
+"            \"title\": \"S\","
+"            \"null_obj\": null, "
+"            \"GlossList\": {"
+"                \"GlossEntry\": {"
+"                    \"ID\": \"SGML\","
+"                    \"SortAs\": \"SGML\","
+"                    \"GlossTerm\": \"Standard Generalized Markup Language\","
+"                    \"Acronym\": \"SGML\","
+"                    \"Abbrev\": \"ISO 8879:1986\","
+"                    \"GlossDef\": {"
+"                        \"para\": \"A meta-markup language, used to create markup languages such as DocBook.\","
+"                        \"GlossSeeAlso\": [\"GML\", \"XML\"]"
+"                    },"
+"                    \"GlossSee\": \"markup\""
+"                }"
+"            }"
+"        }"
+"    }"
+"}";
+
+static const char *json_str2 =
+"{\"menu\": {"
+"    \"header\": \"SVG Viewer\","
+"    \"items\": ["
+"        {\"id\": \"Open\"},"
+"        {\"id\": \"OpenNew\", \"label\": \"Open New\"},"
+"        null,"
+"        {\"id\": \"ZoomIn\", \"label\": \"Zoom In\"},"
+"        {\"id\": \"ZoomOut\", \"label\": \"Zoom Out\"},"
+"        {\"id\": \"OriginalView\", \"label\": \"Original View\"},"
+"        null,"
+"        {\"id\": \"Quality\", \"another_null\": null},"
+"        {\"id\": \"Pause\"},"
+"        {\"id\": \"Mute\"},"
+"        null,"
+"        {\"id\": \"Find\", \"label\": \"Find...\"},"
+"        {\"id\": \"FindAgain\", \"label\": \"Find Again\"},"
+"        {\"id\": \"Copy\"},"
+"        {\"id\": \"CopyAgain\", \"label\": \"Copy Again\"},"
+"        {\"id\": \"CopySVG\", \"label\": \"Copy SVG\"},"
+"        {\"id\": \"ViewSVG\", \"label\": \"View SVG\"},"
+"        {\"id\": \"ViewSource\", \"label\": \"View Source\"},"
+"        {\"id\": \"SaveAs\", \"label\": \"Save As\"},"
+"        null,"
+"        {\"id\": \"Help\"},"
+"        {\"id\": \"About\", \"label\": \"About Adobe CVG Viewer...\"}"
+"    ]"
+"}}";
+
+static const char *json_str3 =
+"{\"menu\": {"
+"  \"id\": \"file\","
+"  \"value\": \"File\","
+"  \"popup\": {"
+"    \"menuitem\": ["
+"      {\"value\": \"New\", \"onclick\": \"CreateNewDoc()\"},"
+"      {\"value\": \"Open\", \"onclick\": \"OpenDoc()\"},"
+"      {\"value\": \"Close\", \"onclick\": \"CloseDoc()\"}"
+"    ]"
+"  }"
+"}}";
+
+int main(int argc, char **argv)
+{
+	struct json_object *src1, *src2, *src3;
+	struct json_object *dst1 = NULL, *dst2 = NULL, *dst3 = NULL;
+
+	src1 = json_tokener_parse(json_str1);
+	src2 = json_tokener_parse(json_str2);
+	src3 = json_tokener_parse(json_str3);
+
+	assert(src1 != NULL);
+	assert(src1 != NULL);
+	assert(src3 != NULL);
+
+	printf("PASSED - loaded input data\n");
+
+	/* do this 3 times to make sure overwriting it works */
+	assert(0 == json_object_deep_copy(src1, &dst1));
+	assert(0 == json_object_deep_copy(src2, &dst2));
+	assert(0 == json_object_deep_copy(src3, &dst3));
+
+	printf("PASSED - all json_object_deep_copy() returned succesful\n");
+
+	assert(-1 == json_object_deep_copy(src1, &dst1));
+	assert(errno == EINVAL);
+	assert(-1 == json_object_deep_copy(src2, &dst2));
+	assert(errno == EINVAL);
+	assert(-1 == json_object_deep_copy(src3, &dst3));
+	assert(errno == EINVAL);
+
+	printf("PASSED - all json_object_deep_copy() returned EINVAL for non-null pointer\n");
+
+	assert(1 == json_object_equal(src1, dst1));
+	assert(1 == json_object_equal(src2, dst2));
+	assert(1 == json_object_equal(src3, dst3));
+
+	printf("PASSED - all json_object_equal() tests returned succesful\n");
+
+	assert(0 == strcmp(json_object_to_json_string_ext(src1, JSON_C_TO_STRING_PRETTY),
+	                   json_object_to_json_string_ext(dst1, JSON_C_TO_STRING_PRETTY)));
+	assert(0 == strcmp(json_object_to_json_string_ext(src2, JSON_C_TO_STRING_PRETTY),
+	                   json_object_to_json_string_ext(dst2, JSON_C_TO_STRING_PRETTY)));
+	assert(0 == strcmp(json_object_to_json_string_ext(src3, JSON_C_TO_STRING_PRETTY),
+	                   json_object_to_json_string_ext(dst3, JSON_C_TO_STRING_PRETTY)));
+
+	printf("PASSED - comparison of string output\n");
+
+	json_object_get(dst1);
+	assert(-1 == json_object_deep_copy(src1, &dst1));
+	assert(errno == EINVAL);
+
+	printf("PASSED - trying to overrwrite an object that has refcount > 1");
+
+	printf("\nPrinting JSON objects for visual inspection\n");
+	printf("------------------------------------------------\n");
+	printf(" JSON1\n");
+	printf("%s", json_object_to_json_string_ext(dst1, JSON_C_TO_STRING_PRETTY));
+	printf("------------------------------------------------\n");
+
+	printf("------------------------------------------------\n");
+	printf(" JSON2\n");
+	printf("%s", json_object_to_json_string_ext(dst2, JSON_C_TO_STRING_PRETTY));
+	printf("------------------------------------------------\n");
+
+	printf("------------------------------------------------\n");
+	printf(" JSON3\n");
+	printf("------------------------------------------------\n");
+	printf("%s", json_object_to_json_string_ext(dst3, JSON_C_TO_STRING_PRETTY));
+	printf("------------------------------------------------\n");
+
+	json_object_put(dst1);
+	json_object_put(dst2);
+	json_object_put(dst3);
+
+#if BENCHMARK
+	/**
+	 * The numbers that I got are:
+	 * BENCHMARK - 1000000 iterations of 'dst2 = json_tokener_parse(json_object_get_string(src2))' took 20 seconds
+	 * BENCHMARK - 1000000 iterations of 'dst2 = json_tokener_parse(json_object_get_string(src2))' took 7 seconds
+	 */
+
+	int iterations = 1000000;
+	time_t start = time(NULL);
+	for (i = 0; i < iterations; i++) {
+		dst2 = json_tokener_parse(json_object_get_string(src2));
+		json_object_put(dst2);
+	}
+	printf("BENCHMARK - %d iterations of 'dst2 = json_tokener_parse(json_object_get_string(src2))' took %d seconds\n", iterations, (int)(time(NULL) - start));
+
+	start = time(NULL);
+	for (i = 0; i < iterations; i++) {
+		json_object_deep_copy(src2, &dst2);
+	}
+	json_object_put(dst2);
+	printf("BENCHMARK - %d iterations of 'dst2 = json_tokener_parse(json_object_get_string(src2))' took %d seconds\n", iterations, (int)(time(NULL) - start));
+#endif
+
+	return 0;
+}

tests/test_deep_copy.expected

@@ -0,0 +1,140 @@
+PASSED - loaded input data
+PASSED - all json_object_deep_copy() returned succesful
+PASSED - all json_object_deep_copy() returned EINVAL for non-null pointer
+PASSED - all json_object_equal() tests returned succesful
+PASSED - comparison of string output
+PASSED - trying to overrwrite an object that has refcount > 1
+Printing JSON objects for visual inspection
+------------------------------------------------
+ JSON1
+{
+  "glossary":{
+    "title":"example glossary",
+    "GlossDiv":{
+      "title":"S",
+      "null_obj":null,
+      "GlossList":{
+        "GlossEntry":{
+          "ID":"SGML",
+          "SortAs":"SGML",
+          "GlossTerm":"Standard Generalized Markup Language",
+          "Acronym":"SGML",
+          "Abbrev":"ISO 8879:1986",
+          "GlossDef":{
+            "para":"A meta-markup language, used to create markup languages such as DocBook.",
+            "GlossSeeAlso":[
+              "GML",
+              "XML"
+            ]
+          },
+          "GlossSee":"markup"
+        }
+      }
+    }
+  }
+}------------------------------------------------
+------------------------------------------------
+ JSON2
+{
+  "menu":{
+    "header":"SVG Viewer",
+    "items":[
+      {
+        "id":"Open"
+      },
+      {
+        "id":"OpenNew",
+        "label":"Open New"
+      },
+      null,
+      {
+        "id":"ZoomIn",
+        "label":"Zoom In"
+      },
+      {
+        "id":"ZoomOut",
+        "label":"Zoom Out"
+      },
+      {
+        "id":"OriginalView",
+        "label":"Original View"
+      },
+      null,
+      {
+        "id":"Quality",
+        "another_null":null
+      },
+      {
+        "id":"Pause"
+      },
+      {
+        "id":"Mute"
+      },
+      null,
+      {
+        "id":"Find",
+        "label":"Find..."
+      },
+      {
+        "id":"FindAgain",
+        "label":"Find Again"
+      },
+      {
+        "id":"Copy"
+      },
+      {
+        "id":"CopyAgain",
+        "label":"Copy Again"
+      },
+      {
+        "id":"CopySVG",
+        "label":"Copy SVG"
+      },
+      {
+        "id":"ViewSVG",
+        "label":"View SVG"
+      },
+      {
+        "id":"ViewSource",
+        "label":"View Source"
+      },
+      {
+        "id":"SaveAs",
+        "label":"Save As"
+      },
+      null,
+      {
+        "id":"Help"
+      },
+      {
+        "id":"About",
+        "label":"About Adobe CVG Viewer..."
+      }
+    ]
+  }
+}------------------------------------------------
+------------------------------------------------
+ JSON3
+------------------------------------------------
+{
+  "menu":{
+    "id":"file",
+    "value":"File",
+    "popup":{
+      "menuitem":[
+        {
+          "value":"New",
+          "onclick":"CreateNewDoc()"
+        },
+        {
+          "value":"Open",
+          "onclick":"OpenDoc()"
+        },
+        {
+          "value":"Close",
+          "onclick":"CloseDoc()"
+        }
+      ]
+    }
+  }
+}------------------------------------------------

tests/test_deep_copy.test

@@ -0,0 +1 @@
+test_basic.test