feature: added new cjson.array_mt metatable to allow enforcing JSON array encoding.

Signed-off-by: Yichun Zhang (agentzh) <agentzh@gmail.com>
author: Thibault Charbonnier <thibaultcha@me.com> 2017-07-08 21:54:18 -0700
committer: Yichun Zhang (agentzh) <agentzh@gmail.com> 2017-11-15 20:41:57 -0800
commit: 5f9efa4829a72935ddcd40c7da6b1a9e10939b65 (patch)
tree: 319cdf13f99c753f85820c3fabb89bfa50496dae /lua_cjson.c
parent: a9af7965219710ac1ec1e2bbf1a63eb77be622b7 (diff)
download: lua-cjson-5f9efa4829a72935ddcd40c7da6b1a9e10939b65.tar.gz
lua-cjson-5f9efa4829a72935ddcd40c7da6b1a9e10939b65.tar.bz2
lua-cjson-5f9efa4829a72935ddcd40c7da6b1a9e10939b65.zip
1 files changed, 46 insertions, 17 deletions
diff --git a/lua_cjson.c b/lua_cjson.c
index d04f151..8d6e313 100644
--- a/lua_cjson.c
+++ b/lua_cjson.c
@@ -92,6 +92,7 @@
 #endif
 static const char * const *json_empty_array;
+static const char * const *json_array;
 typedef enum {
    T_OBJ_BEGIN,
@@ -713,21 +714,37 @@ static void json_append_data(lua_State *l, json_config_t *cfg,
    case LUA_TTABLE:
        current_depth++;
        json_check_encode_depth(l, cfg, current_depth, json);
-        len = lua_array_length(l, cfg, json);
-        if (len > 0 || (len == 0 && !cfg->encode_empty_table_as_object))
+        int as_array = 0;
+        int has_metatable = lua_getmetatable(l, -1);
+        if (has_metatable) {
+            lua_pushlightuserdata(l, &json_array);
+            lua_rawget(l, LUA_REGISTRYINDEX);
+            as_array = lua_rawequal(l, -1, -2);
+            lua_pop(l, 2);
+        }
+        if (as_array) {
+            len = lua_objlen(l, -1);
            json_append_array(l, cfg, current_depth, json, len);
-        else {
+        } else {
-            int as_array = 0;
+            len = lua_array_length(l, cfg, json);
-            if (lua_getmetatable(l, -1)) {
-                lua_pushlightuserdata(l, &json_empty_array);
-                lua_rawget(l, LUA_REGISTRYINDEX);
-                as_array = lua_rawequal(l, -1, -2);
-                lua_pop(l, 2);
-            }
-            if (as_array) {
+            if (len > 0 || (len == 0 && !cfg->encode_empty_table_as_object)) {
-                json_append_array(l, cfg, current_depth, json, 0);
+                json_append_array(l, cfg, current_depth, json, len);
            } else {
+                if (has_metatable) {
+                    lua_getmetatable(l, -1);
+                    lua_pushlightuserdata(l, &json_empty_array);
+                    lua_rawget(l, LUA_REGISTRYINDEX);
+                    as_array = lua_rawequal(l, -1, -2);
+                    lua_pop(l, 2); /* pop pointer + metatable */
+                    if (as_array) {
+                        json_append_array(l, cfg, current_depth, json, 0);
+                        break;
+                    }
+                }
                json_append_object(l, cfg, current_depth, json);
            }
        }
@@ -738,7 +755,7 @@ static void json_append_data(lua_State *l, json_config_t *cfg,
    case LUA_TLIGHTUSERDATA:
        if (lua_touserdata(l, -1) == NULL) {
            strbuf_append_mem(json, "null", 4);
-        } else if (lua_touserdata(l, -1) == &json_empty_array) {
+        } else if (lua_touserdata(l, -1) == &json_array) {
            json_append_array(l, cfg, current_depth, json, 0);
        }
        break;
@@ -1412,20 +1429,27 @@ static int lua_cjson_new(lua_State *l)
    /* Initialise number conversions */
    fpconv_init();
-    /* Test if empty array metatable is in registry */
+    /* Test if array metatables are in registry */
    lua_pushlightuserdata(l, &json_empty_array);
    lua_rawget(l, LUA_REGISTRYINDEX);
    if (lua_isnil(l, -1)) {
-        /* Create empty array metatable.
+        /* Create array metatables.
         *
         * If multiple calls to lua_cjson_new() are made,
-         * this prevents overriding the table at the given
+         * this prevents overriding the tables at the given
         * registry's index with a new one.
         */
        lua_pop(l, 1);
+        /* empty_array_mt */
        lua_pushlightuserdata(l, &json_empty_array);
        lua_newtable(l);
        lua_rawset(l, LUA_REGISTRYINDEX);
+        /* array_mt */
+        lua_pushlightuserdata(l, &json_array);
+        lua_newtable(l);
+        lua_rawset(l, LUA_REGISTRYINDEX);
    }
    /* cjson module table */
@@ -1444,8 +1468,13 @@ static int lua_cjson_new(lua_State *l)
    lua_rawget(l, LUA_REGISTRYINDEX);
    lua_setfield(l, -2, "empty_array_mt");
+    /* Set cjson.array_mt */
+    lua_pushlightuserdata(l, &json_array);
+    lua_rawget(l, LUA_REGISTRYINDEX);
+    lua_setfield(l, -2, "array_mt");
    /* Set cjson.empty_array */
-    lua_pushlightuserdata(l, &json_empty_array);
+    lua_pushlightuserdata(l, &json_array);
    lua_setfield(l, -2, "empty_array");
    /* Set module name / version fields */
author	Thibault Charbonnier <thibaultcha@me.com>	2017-07-08 21:54:18 -0700
committer	Yichun Zhang (agentzh) <agentzh@gmail.com>	2017-11-15 20:41:57 -0800
commit	5f9efa4829a72935ddcd40c7da6b1a9e10939b65 (patch)
tree	319cdf13f99c753f85820c3fabb89bfa50496dae /lua_cjson.c
parent	a9af7965219710ac1ec1e2bbf1a63eb77be622b7 (diff)
download	lua-cjson-5f9efa4829a72935ddcd40c7da6b1a9e10939b65.tar.gz lua-cjson-5f9efa4829a72935ddcd40c7da6b1a9e10939b65.tar.bz2 lua-cjson-5f9efa4829a72935ddcd40c7da6b1a9e10939b65.zip

diff --git a/lua_cjson.c b/lua_cjson.c index d04f151..8d6e313 100644 --- a/lua_cjson.c +++ b/lua_cjson.c
@@ -92,6 +92,7 @@
92	#endif	92	#endif
93		93
94	static const char * const *json_empty_array;	94	static const char * const *json_empty_array;
		95	static const char * const *json_array;
95		96
96	typedef enum {	97	typedef enum {
97	T_OBJ_BEGIN,	98	T_OBJ_BEGIN,
@@ -713,21 +714,37 @@ static void json_append_data(lua_State l, json_config_t cfg,
713	case LUA_TTABLE:	714	case LUA_TTABLE:
714	current_depth++;	715	current_depth++;
715	json_check_encode_depth(l, cfg, current_depth, json);	716	json_check_encode_depth(l, cfg, current_depth, json);
716	len = lua_array_length(l, cfg, json);	717
717	if (len > 0 \|\| (len == 0 && !cfg->encode_empty_table_as_object))	718	int as_array = 0;
		719	int has_metatable = lua_getmetatable(l, -1);
		720
		721	if (has_metatable) {
		722	lua_pushlightuserdata(l, &json_array);
		723	lua_rawget(l, LUA_REGISTRYINDEX);
		724	as_array = lua_rawequal(l, -1, -2);
		725	lua_pop(l, 2);
		726	}
		727
		728	if (as_array) {
		729	len = lua_objlen(l, -1);
718	json_append_array(l, cfg, current_depth, json, len);	730	json_append_array(l, cfg, current_depth, json, len);
719	else {	731	} else {
720	int as_array = 0;	732	len = lua_array_length(l, cfg, json);
721	if (lua_getmetatable(l, -1)) {
722	lua_pushlightuserdata(l, &json_empty_array);
723	lua_rawget(l, LUA_REGISTRYINDEX);
724	as_array = lua_rawequal(l, -1, -2);
725	lua_pop(l, 2);
726	}
727		733
728	if (as_array) {	734	if (len > 0 \|\| (len == 0 && !cfg->encode_empty_table_as_object)) {
729	json_append_array(l, cfg, current_depth, json, 0);	735	json_append_array(l, cfg, current_depth, json, len);
730	} else {	736	} else {
		737	if (has_metatable) {
		738	lua_getmetatable(l, -1);
		739	lua_pushlightuserdata(l, &json_empty_array);
		740	lua_rawget(l, LUA_REGISTRYINDEX);
		741	as_array = lua_rawequal(l, -1, -2);
		742	lua_pop(l, 2); /* pop pointer + metatable */
		743	if (as_array) {
		744	json_append_array(l, cfg, current_depth, json, 0);
		745	break;
		746	}
		747	}
731	json_append_object(l, cfg, current_depth, json);	748	json_append_object(l, cfg, current_depth, json);
732	}	749	}
733	}	750	}
@@ -738,7 +755,7 @@ static void json_append_data(lua_State l, json_config_t cfg,
738	case LUA_TLIGHTUSERDATA:	755	case LUA_TLIGHTUSERDATA:
739	if (lua_touserdata(l, -1) == NULL) {	756	if (lua_touserdata(l, -1) == NULL) {
740	strbuf_append_mem(json, "null", 4);	757	strbuf_append_mem(json, "null", 4);
741	} else if (lua_touserdata(l, -1) == &json_empty_array) {	758	} else if (lua_touserdata(l, -1) == &json_array) {
742	json_append_array(l, cfg, current_depth, json, 0);	759	json_append_array(l, cfg, current_depth, json, 0);
743	}	760	}
744	break;	761	break;
@@ -1412,20 +1429,27 @@ static int lua_cjson_new(lua_State *l)
1412	/* Initialise number conversions */	1429	/* Initialise number conversions */
1413	fpconv_init();	1430	fpconv_init();
1414		1431
1415	/* Test if empty array metatable is in registry */	1432	/* Test if array metatables are in registry */
1416	lua_pushlightuserdata(l, &json_empty_array);	1433	lua_pushlightuserdata(l, &json_empty_array);
1417	lua_rawget(l, LUA_REGISTRYINDEX);	1434	lua_rawget(l, LUA_REGISTRYINDEX);
1418	if (lua_isnil(l, -1)) {	1435	if (lua_isnil(l, -1)) {
1419	/* Create empty array metatable.	1436	/* Create array metatables.
1420	*	1437	*
1421	* If multiple calls to lua_cjson_new() are made,	1438	* If multiple calls to lua_cjson_new() are made,
1422	* this prevents overriding the table at the given	1439	* this prevents overriding the tables at the given
1423	* registry's index with a new one.	1440	* registry's index with a new one.
1424	*/	1441	*/
1425	lua_pop(l, 1);	1442	lua_pop(l, 1);
		1443
		1444	/* empty_array_mt */
1426	lua_pushlightuserdata(l, &json_empty_array);	1445	lua_pushlightuserdata(l, &json_empty_array);
1427	lua_newtable(l);	1446	lua_newtable(l);
1428	lua_rawset(l, LUA_REGISTRYINDEX);	1447	lua_rawset(l, LUA_REGISTRYINDEX);
		1448
		1449	/* array_mt */
		1450	lua_pushlightuserdata(l, &json_array);
		1451	lua_newtable(l);
		1452	lua_rawset(l, LUA_REGISTRYINDEX);
1429	}	1453	}
1430		1454
1431	/* cjson module table */	1455	/* cjson module table */
@@ -1444,8 +1468,13 @@ static int lua_cjson_new(lua_State *l)
1444	lua_rawget(l, LUA_REGISTRYINDEX);	1468	lua_rawget(l, LUA_REGISTRYINDEX);
1445	lua_setfield(l, -2, "empty_array_mt");	1469	lua_setfield(l, -2, "empty_array_mt");
1446		1470
		1471	/* Set cjson.array_mt */
		1472	lua_pushlightuserdata(l, &json_array);
		1473	lua_rawget(l, LUA_REGISTRYINDEX);
		1474	lua_setfield(l, -2, "array_mt");
		1475
1447	/* Set cjson.empty_array */	1476	/* Set cjson.empty_array */
1448	lua_pushlightuserdata(l, &json_empty_array);	1477	lua_pushlightuserdata(l, &json_array);
1449	lua_setfield(l, -2, "empty_array");	1478	lua_setfield(l, -2, "empty_array");
1450		1479
1451	/* Set module name / version fields */	1480	/* Set module name / version fields */