4 files changed, 109 insertions, 0 deletions
diff --git a/.gitmodules b/.gitmodules
index b83fa2d..0e514da 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -20,3 +20,6 @@
 	url = https://github.com/Mbed-TLS/mbedtls.git
 	tag = mbedtls-2.28.3
 	shallow = true
+[submodule "lib/cJSON"]
+	path = lib/cJSON
+	url = https://github.com/DaveGamble/cJSON
diff --git a/lib/cJSON b/lib/cJSON
new file mode 160000
+Subproject 87d8f0961a01bf09bef98ff89bae9fdec42181e
diff --git a/libraries/json.c b/libraries/json.c
new file mode 100644
index 0000000..1ee5e85
--- /dev/null
+++ b/libraries/json.c
@@ -0,0 +1,99 @@
+#include "cJSON.h"
+#include "cJSON.c"
+
+// Lua binidngs.
+static void f_cjson_push(lua_State* L, cJSON* json, int value) {
+    if (json) {
+        switch (json->type) {
+            case cJSON_Array:
+            case cJSON_Object: {
+                cJSON** value = lua_newuserdata(L, sizeof(cJSON*));
+                luaL_setmetatable(L, value ? "cjson_value" : "cjson_object");
+                *value = *json;
+            } break;
+            case cJSON_NULL: lua_pushnil(L); break;
+            case cJSON_Number: lua_pushnumber(L, json->number); break;
+            case cJSON_String: lua_pushlstring(L, json_string(json), json->length); break;
+        }
+    } else
+        lua_pushnil(L);
+}
+
+
+static int f_cjson_object_gc(lua_State* L) {
+    cJSON** data = lua_touserdata(L, 1);
+    cJSON_free(*data);
+}
+
+static int f_cjson_object_index(lua_State* L) {
+    cJSON* json = *(cJSON**)lua_touserdata(L, 1);
+    switch (json->type) {
+        case cJSON_Object: f_cjson_push(L, cJSON_GetObjectItem(json, luaL_checkstring(L, 2)), 1); break;
+        case cJSON_Array: f_cjson_push(L, cJSON_GetArrayItem(json, luaL_checkinteger(L, 2) - 1), 1); break;
+        default: return luaL_error(L, "invalid index");
+    }
+    return 1;
+}
+
+static int f_cjson_object_len(lua_State* L) {
+    cJSON* json = *(cJSON**)lua_touserdata(L, 1);
+    switch (json->type) {
+        case cJSON_Array: lua_pushinteger(L, cJSON_GetArraySize(json->length)); break;
+        default: return luaL_error(L, "length operation invalid");
+    }
+    return 1;
+}
+
+
+static const luaL_Reg cjson_value[] = {
+    { "__index",     f_cjson_object_index },
+    { "__newindex",  f_cjson_object_newindex },
+    { "__pairs",     f_cjson_object_pairs },
+    { "__len",       f_cjson_object_len },
+    { NULL,          NULL             }
+};
+
+static const luaL_Reg cjson_object[] = {
+    { "__gc",        f_cjson_object_gc   },
+    { "__index",     f_cjson_object_index },
+    { "__newindex",  f_cjson_object_newindex },
+    { "__pairs",     f_cjson_object_pairs },
+    { "__len",       f_cjson_object_len },
+    { NULL,          NULL             }
+};
+
+
+static int f_cjson_encode(lua_State* L) {
+    cJSON** data = lua_touserdata(L, 1);
+    char* str = cJSON_PrintUnformatted(*data);
+    lua_pushstring(L, str);
+    free(str);
+    return 1;
+}
+
+
+static int f_cjson_decode(lua_State* L) {
+    size_t len;
+    const char* str = luaL_checklstring(L, 1, &len);
+    cJSON* value = cJSON_ParseWithLength(str, len);
+    cJSON** data = lua_newuserdata(L, sizeof(cJSON*));
+    luaL_setmetatable(L, "cjson_object");
+    *data = value;
+    return 1;
+}
+
+#ifndef CJSON_STANDALONE
+int luaopen_lite_xl_cjson(lua_State* L, void* XL) {
+  lite_xl_plugin_init(XL);
+#else
+int luaopen_cjson(lua_State* L) {
+#endif
+    luaL_newmetatable(L, "cjson_object");
+    luaL_setfuncs(L, cjson_object, 0);
+    luaL_newmetatable(L, "cjson_value");
+    luaL_setfuncs(L, cjson_value, 0);
+    lua_newtable(L);
+    luaL_setfuncs(L, cjson_lib, 0);
+    return 1;
+}
+
diff --git a/libraries/json.lua b/libraries/json.lua
index c463440..3499195 100644
--- a/libraries/json.lua
+++ b/libraries/json.lua
@@ -385,5 +385,12 @@ function json.decode(str)
   return res
 end
 
+local status, cjson = pcall(require, "libraries.cjson")
+if status then
+  json.ldecode = json.decode
+  json.lencode = json.encode
+  json.decode = cjson.decode
+  json.encode = cjson.encode
+end
 
 return json