/* * luaobject.h - useful functions for handling Lua objects * * Copyright © 2009 Julien Danjou * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * */ #ifndef AWESOME_COMMON_LUAOBJECT #define AWESOME_COMMON_LUAOBJECT #include "common/signal.h" static inline int luaA_settype(lua_State *L, const char *type) { luaL_getmetatable(L, type); lua_setmetatable(L, -2); return 1; } #define LUAA_OBJECT_REGISTRY_KEY "awesome.object.registry" void luaA_object_setup(lua_State *); void * luaA_object_incref(lua_State *, int, int); void luaA_object_decref(lua_State *, int, void *); /** Store an item in the environment table of an object. * \param L The Lua VM state. * \param ud The index of the object on the stack. * \param iud The index of the item on the stack. * \return The item reference. */ static inline void * luaA_object_ref_item(lua_State *L, int ud, int iud) { /* Get the env table from the object */ lua_getfenv(L, ud); void *pointer = luaA_object_incref(L, -1, iud < 0 ? iud - 1 : iud); /* Remove env table */ lua_pop(L, 1); return pointer; } /** Unref an item from the environment table of an object. * \param L The Lua VM state. * \param ud The index of the object on the stack. * \param ref item. */ static inline void luaA_object_unref_item(lua_State *L, int ud, void *pointer) { /* Get the env table from the object */ lua_getfenv(L, ud); /* Decrement */ luaA_object_decref(L, -1, pointer); /* Remove env table */ lua_pop(L, 1); } /** Push an object item on the stack. * \param L The Lua VM state. * \param ud The object index on the stack. * \param pointer The item pointer. * \return The number of element pushed on stack. */ static inline int luaA_object_push_item(lua_State *L, int ud, void *pointer) { /* Get env table of the object */ lua_getfenv(L, ud); /* Push key */ lua_pushlightuserdata(L, pointer); /* Get env.pointer */ lua_rawget(L, -2); /* Remove env table */ lua_remove(L, -2); return 1; } static inline void luaA_object_registry_push(lua_State *L) { lua_pushliteral(L, LUAA_OBJECT_REGISTRY_KEY); lua_rawget(L, LUA_REGISTRYINDEX); } /** Reference an object and return a pointer to it. * That only works with userdata, table, thread or function. * \param L The Lua VM state. * \param oud The object index on the stack. * \return The object reference, or NULL if not referencable. */ static inline void * luaA_object_ref(lua_State *L, int oud) { luaA_object_registry_push(L); void *p = luaA_object_incref(L, -1, oud < 0 ? oud - 1 : oud); lua_pop(L, 1); return p; } /** Unreference an object and return a pointer to it. * That only works with userdata, table, thread or function. * \param L The Lua VM state. * \param oud The object index on the stack. */ static inline void luaA_object_unref(lua_State *L, void *pointer) { luaA_object_registry_push(L); luaA_object_decref(L, -1, pointer); lua_pop(L, 1); } /** Push a referenced object onto the stack. * \param L The Lua VM state. * \param pointer The object to push. * \return The number of element pushed on stack. */ static inline int luaA_object_push(lua_State *L, void *pointer) { luaA_object_registry_push(L); lua_pushlightuserdata(L, pointer); lua_rawget(L, -2); lua_remove(L, -2); return 1; } void luaA_object_add_signal(lua_State *, int, const char *, int); void luaA_object_remove_signal(lua_State *, int, const char *, int); void luaA_object_emit_signal(lua_State *, int, const char *, int); int luaA_object_add_signal_simple(lua_State *); int luaA_object_remove_signal_simple(lua_State *); int luaA_object_emit_signal_simple(lua_State *); #define LUA_OBJECT_HEADER \ signal_array_t signals; /** Generic type for all objects. * All Lua objects can be casted to this type. */ typedef struct { LUA_OBJECT_HEADER } lua_object_t; #define LUA_OBJECT_FUNCS(type, prefix, lua_type) \ static inline type * \ prefix##_new(lua_State *L) \ { \ type *p = lua_newuserdata(L, sizeof(type)); \ p_clear(p, 1); \ luaA_settype(L, lua_type); \ lua_newtable(L); \ lua_newtable(L); \ lua_setmetatable(L, -2); \ lua_setfenv(L, -2); \ return p; \ } \ \ static inline int \ prefix##_push(lua_State *L, type *item) \ { \ return luaA_object_push(L, item); \ } \ \ static inline type * \ prefix##_ref(lua_State *L, int ud) \ { \ return luaA_object_ref(L, ud); \ } \ \ static inline void \ prefix##_unref(lua_State *L, type *item) \ { \ luaA_object_unref(L, item); \ } \ \ static inline int \ prefix##_push_item(lua_State *L, type *item, void *ref) \ { \ prefix##_push(L, item); \ luaA_object_push_item(L, -1, ref); \ lua_remove(L, -2); \ return 1; \ } /** Garbage collect a Lua object. * \param L The Lua VM state. * \return The number of elements pushed on stack. */ static inline int luaA_object_gc(lua_State *L) { lua_object_t *item = lua_touserdata(L, 1); signal_array_wipe(&item->signals); return 0; } #define LUA_OBJECT_META \ { "add_signal", luaA_object_add_signal_simple }, \ { "remove_signal", luaA_object_remove_signal_simple }, \ { "emit_signal", luaA_object_emit_signal_simple }, #endif // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80