LuCI Core C-Rewrite: First steps

[project/luci.git] / libs / core / src / luci_cutil.c

diff --git a/libs/core/src/luci_cutil.c b/libs/core/src/luci_cutil.c
new file mode 100644 (file)
index 0000000..001273b
--- /dev/null
+++ b/libs/core/src/luci_cutil.c
@@ -0,0 +1,140 @@
+/**
+ * LuCI Core - Utility library
+ * Copyright (C) 2008 Steven Barth <steven@midlink.org>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "lauxlib.h"
+
+#define LUCI_MODNAME "luci.cutil"
+#define LUCI_MODDESC "LuCI Core Utility Library"
+#define LUCI_MODCOPY "2008 Steven Barth"
+
+
+/* Pythonic overloaded MOD operator */
+static int luci__string_mod(lua_State *L) {
+       int i, n=1;
+
+       luaL_checkstring(L, 1);
+       luaL_checkany(L, 2);
+
+       /* Discard further arguments */
+       lua_settop(L, 2);
+
+       /* Get format and push it to the bottom of the stack */
+       lua_pushliteral(L, "");
+       lua_getfield(L, -1, "format");
+       lua_insert(L, 1);
+       lua_pop(L, 1);
+
+       /* If second argument is a table, unpack it */
+       if (lua_istable(L, 3)) {
+               n = luaL_getn(L, 3);
+               if (n > 0) {
+                       luaL_checkstack(L, n, "too many results to unpack");
+                       for (i=1; i<=n; i++) {
+                               lua_rawgeti(L, 3, i);
+                       }
+               } else {
+                       n = 0;
+               }
+               lua_remove(L, 3);
+       }
+
+       lua_call(L, n+1, 1);
+       return 1;
+}
+
+/* Instantiate a class */
+static int luci__instantiate(lua_State *L) {
+       luaL_checktype(L, 1, LUA_TTABLE);
+
+       /* Create the object */
+       lua_newtable(L);
+
+       /* Create the metatable */
+       lua_createtable(L, 0, 1);
+       lua_pushvalue(L, 1);
+       lua_setfield(L, -2, "__index");
+       lua_setmetatable(L, -2);
+
+       /* Move instance at the bottom of the stack */
+       lua_replace(L, 1);
+
+       /* Invoke constructor if it exists */
+       lua_getfield(L, 1, "__init__");
+       if (lua_isfunction(L, -1)) {
+               /* Put instance at the bottom for the 2nd time */
+               lua_pushvalue(L, 1);
+               lua_insert(L, 1);
+
+               /* Call constructor */
+               lua_insert(L, 2);
+               lua_call(L, lua_gettop(L)-2, 0);
+       }
+
+       lua_settop(L, 1);
+       return 1;
+}
+
+
+/* luci.cutil.class(baseclass) */
+static int luci_class(lua_State *L) {
+       /* Create class */
+       lua_newtable(L);
+
+       /* Create metatable and register parent class if any */
+       if (lua_istable(L, 1)) {
+               lua_createtable(L, 0, 2);
+               lua_pushvalue(L, 1);
+               lua_setfield(L, -2, "__index");
+       } else {
+               lua_createtable(L, 0, 1);
+       }
+
+       /* Set instantiator */
+       lua_pushcfunction(L, luci__instantiate);
+       lua_setfield(L, -2, "__call");
+
+       lua_setmetatable(L, -2);
+       return 1;
+}
+
+
+/* Registry */
+static const luaL_Reg registry[] = {
+               {"class",               luci_class},
+               { NULL,                 NULL },
+};
+
+/* Registrator */
+LUALIB_API int luaopen_luci_cutil(lua_State *L) {
+       luaL_register(L, LUCI_MODNAME, registry);
+
+       lua_pushliteral(L, LUCI_MODDESC);
+       lua_setfield(L, -2, "_DESCRIPTION");
+
+       lua_pushliteral(L, LUCI_MODCOPY);
+       lua_setfield(L, -2, "_COPYRIGHT");
+
+
+       /* Register pythonic printf string operator */
+       lua_pushliteral(L, "");
+       lua_getmetatable(L, -1);
+       lua_pushcfunction(L, luci__string_mod);
+       lua_setfield(L, -2, "__mod");
+       lua_pop(L, 2);
+
+       return 1;
+}