lua.h

   1 /*
   2  * lua.h - Lua configuration management header
   3  *
   4  * Copyright © 2008 Julien Danjou <julien@danjou.info>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  */
  21
  22 #ifndef AWESOME_LUA_H
  23 #define AWESOME_LUA_H
  24
  25 #include <ev.h>
  26 #include <lua.h>
  27 #include <lauxlib.h>
  28
  29 #include "common/util.h"
  30 #include "common/draw.h"
  31
  32 /** Object types */
  33 typedef enum
  34 {
  35     AWESOME_TYPE_STATUSBAR = 1,
  36     AWESOME_TYPE_TITLEBAR
  37 } awesome_type_t;
  38
  39 /** Type for Lua function */
  40 typedef int luaA_ref;
  41
  42 #define DO_LUA_NEW(decl, type, prefix, lua_type, type_ref) \
  43     decl int \
  44     luaA_##prefix##_userdata_new(lua_State *L, type *p) \
  45     { \
  46         type **pp = lua_newuserdata(L, sizeof(type *)); \
  47         *pp = p; \
  48         type_ref(pp); \
  49         return luaA_settype(L, lua_type); \
  50     }
  51
  52 #define DO_LUA_GC(type, prefix, lua_type, type_unref) \
  53     static int \
  54     luaA_##prefix##_gc(lua_State *L) \
  55     { \
  56         type **p = luaA_checkudata(L, 1, lua_type); \
  57         type_unref(p); \
  58         *p = NULL; \
  59         return 0; \
  60     }
  61
  62 #define DO_LUA_EQ(type, prefix, lua_type) \
  63     static int \
  64     luaA_##prefix##_eq(lua_State *L) \
  65     { \
  66         type **p1 = luaA_checkudata(L, 1, lua_type); \
  67         type **p2 = luaA_checkudata(L, 2, lua_type); \
  68         lua_pushboolean(L, (*p1 == *p2)); \
  69         return 1; \
  70     }
  71
  72 #define luaA_dostring(L, cmd) \
  73     do { \
  74         if(a_strlen(cmd)) \
  75             if(luaL_dostring(L, cmd)) \
  76                 warn("error executing Lua code: %s", \
  77                      lua_tostring(L, -1)); \
  78     } while(0)
  79
  80 #define luaA_checktable(L, n) \
  81     do { \
  82         if(!lua_istable(L, n)) \
  83             luaL_typerror(L, n, "table"); \
  84     } while(0)
  85
  86 #define luaA_checkfunction(L, n) \
  87     do { \
  88         if(!lua_isfunction(L, n)) \
  89             luaL_typerror(L, n, "function"); \
  90     } while(0)
  91
  92 #define luaA_checkscreen(screen) \
  93     do { \
  94         if(screen < 0 || screen >= globalconf.screens_info->nscreen) \
  95             luaL_error(L, "invalid screen number: %d", screen); \
  96     } while(0)
  97
  98 /** Check that an object is not a NULL reference.
  99  * \param L The Lua state.
 100  * \param ud The index of the object in the stack.
 101  * \param tname The type name.
 102  * \return A pointer to the object.
 103  */
 104 static inline void *
 105 luaA_checkudata(lua_State *L, int ud, const char *tname)
 106 {
 107     void **p = luaL_checkudata(L, ud, tname);
 108     if(*p)
 109         return p;
 110     luaL_error(L, "invalid object");
 111     return NULL;
 112 }
 113
 114 static inline bool
 115 luaA_checkboolean(lua_State *L, int n)
 116 {
 117     if(!lua_isboolean(L, n))
 118         luaL_typerror(L, n, "boolean");
 119     return lua_toboolean(L, n);
 120 }
 121
 122 static inline bool
 123 luaA_optboolean(lua_State *L, int idx, bool def)
 124 {
 125     return luaL_opt(L, luaA_checkboolean, idx, def);
 126 }
 127
 128 static inline lua_Number
 129 luaA_getopt_number(lua_State *L, int idx, const char *name, lua_Number def)
 130 {
 131     lua_getfield(L, idx, name);
 132     return luaL_optnumber(L, -1, def);
 133 }
 134
 135 static inline const char *
 136 luaA_getopt_lstring(lua_State *L, int idx, const char *name, const char *def, size_t *len)
 137 {
 138     lua_getfield(L, idx, name);
 139     return luaL_optlstring(L, -1, def, len);
 140 }
 141
 142 static inline const char *
 143 luaA_getopt_string(lua_State *L, int idx, const char *name, const char *def)
 144 {
 145     return luaA_getopt_lstring(L, idx, name, def, NULL);
 146 }
 147
 148 static inline bool
 149 luaA_getopt_boolean(lua_State *L, int idx, const char *name, bool def)
 150 {
 151     lua_getfield(L, idx, name);
 152     return luaA_optboolean(L, -1, def);
 153 }
 154
 155 static inline int
 156 luaA_settype(lua_State *L, const char *type)
 157 {
 158     luaL_getmetatable(L, type);
 159     lua_setmetatable(L, -2);
 160     return 1;
 161 }
 162
 163 static inline int
 164 luaA_usemetatable(lua_State *L, int idxobj, int idxfield)
 165 {
 166     lua_getmetatable(L, idxobj);
 167     lua_pushvalue(L, idxfield);
 168     lua_rawget(L, -2);
 169     if (!lua_isnil(L, -1))
 170     {
 171         lua_remove(L, -2);
 172         return 1;
 173     }
 174     lua_pop(L, 2);
 175
 176     return 0;
 177 }
 178
 179 /** Register a function.
 180  * \param L The Lua stack.
 181  * \param fct A luaA_ref address: it will be filled with the luaA_ref
 182  * registered. If the adresse point to an already registered function, it will
 183  * be unregistered.
 184  * \return Always 0.
 185  */
 186 static inline int
 187 luaA_registerfct(lua_State *L, luaA_ref *fct)
 188 {
 189     luaA_checkfunction(L, -1);
 190     if(*fct != LUA_REFNIL)
 191         luaL_unref(L, LUA_REGISTRYINDEX, *fct);
 192     *fct = luaL_ref(L, LUA_REGISTRYINDEX);
 193     return 0;
 194 }
 195
 196 /** Execute an Lua function.
 197  * \param L The Lua stack.
 198  * \param f The Lua function to execute.
 199  * \param nargs The number of arguments for the Lua function.
 200  * \param nret The number of returned value from the Lua function.
 201  * \return True on no error, false otherwise.
 202  */
 203 static inline bool
 204 luaA_dofunction(lua_State *L, luaA_ref f, int nargs, int nret)
 205 {
 206     if(f != LUA_REFNIL)
 207     {
 208         lua_rawgeti(L, LUA_REGISTRYINDEX, f);
 209         if(nargs)
 210             lua_insert(L, - (nargs + 1));
 211         if(lua_pcall(L, nargs, nret, 0))
 212         {
 213             warn("error running function: %s",
 214                  lua_tostring(L, -1));
 215             lua_pop(L, 1);
 216             return false;
 217         }
 218         return true;
 219     }
 220     return false;
 221 }
 222
 223 int luaA_otable_index(lua_State *);
 224
 225 /** Create a new object table with a metatable.
 226  * This is useful to compare table with objects (udata) as keys.
 227  * \param L The Lua stack.
 228  * \return The number of elements pushed on stack.
 229  */
 230 static inline int
 231 luaA_otable_new(lua_State *L)
 232 {
 233     /* Our object */
 234     lua_newtable(L);
 235     /* The meta table */
 236     lua_newtable(L);
 237     lua_pushcfunction(L, luaA_otable_index);
 238     /* Register index into the metatable */
 239     lua_setfield(L, -2, "__index");
 240     /* Set the meta table */
 241     lua_setmetatable(L, -2);
 242     return 1;
 243 }
 244
 245 void luaA_init(void);
 246 void luaA_parserc(const char *);
 247 void luaA_pushpointer(lua_State *, void *, awesome_type_t);
 248 void luaA_cs_init(void);
 249 void luaA_cs_cleanup(void);
 250 void luaA_on_timer(EV_P_ ev_timer *w, int revents);
 251 void luaA_pushcolor(lua_State *, const xcolor_t *);
 252
 253 static inline int
 254 luaA_generic_pairs(lua_State *L)
 255 {
 256     lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */
 257     lua_pushvalue(L, 1);  /* state, */
 258     lua_pushnil(L);  /* and initial value */
 259     return 3;
 260 }
 261
 262 #endif
 263 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80