rlm@1: /*
rlm@1: ** $Id: ltm.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
rlm@1: ** Tag methods
rlm@1: ** See Copyright Notice in lua.h
rlm@1: */
rlm@1: 
rlm@1: 
rlm@1: #include <string.h>
rlm@1: 
rlm@1: #define ltm_c
rlm@1: #define LUA_CORE
rlm@1: 
rlm@1: #include "lua.h"
rlm@1: 
rlm@1: #include "lobject.h"
rlm@1: #include "lstate.h"
rlm@1: #include "lstring.h"
rlm@1: #include "ltable.h"
rlm@1: #include "ltm.h"
rlm@1: 
rlm@1: 
rlm@1: 
rlm@1: const char *const luaT_typenames[] = {
rlm@1:   "nil", "boolean", "userdata", "number",
rlm@1:   "string", "table", "function", "userdata", "thread",
rlm@1:   "proto", "upval"
rlm@1: };
rlm@1: 
rlm@1: 
rlm@1: void luaT_init (lua_State *L) {
rlm@1:   static const char *const luaT_eventname[] = {  /* ORDER TM */
rlm@1:     "__index", "__newindex",
rlm@1:     "__gc", "__mode", "__eq",
rlm@1:     "__add", "__sub", "__mul", "__div", "__mod",
rlm@1:     "__pow", "__unm", "__len", "__lt", "__le",
rlm@1:     "__concat", "__call"
rlm@1:   };
rlm@1:   int i;
rlm@1:   for (i=0; i<TM_N; i++) {
rlm@1:     G(L)->tmname[i] = luaS_new(L, luaT_eventname[i]);
rlm@1:     luaS_fix(G(L)->tmname[i]);  /* never collect these names */
rlm@1:   }
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: /*
rlm@1: ** function to be used with macro "fasttm": optimized for absence of
rlm@1: ** tag methods
rlm@1: */
rlm@1: const TValue *luaT_gettm (Table *events, TMS event, TString *ename) {
rlm@1:   const TValue *tm = luaH_getstr(events, ename);
rlm@1:   lua_assert(event <= TM_EQ);
rlm@1:   if (ttisnil(tm)) {  /* no tag method? */
rlm@1:     events->flags |= cast_byte(1u<<event);  /* cache this fact */
rlm@1:     return NULL;
rlm@1:   }
rlm@1:   else return tm;
rlm@1: }
rlm@1: 
rlm@1: 
rlm@1: const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) {
rlm@1:   Table *mt;
rlm@1:   switch (ttype(o)) {
rlm@1:     case LUA_TTABLE:
rlm@1:       mt = hvalue(o)->metatable;
rlm@1:       break;
rlm@1:     case LUA_TUSERDATA:
rlm@1:       mt = uvalue(o)->metatable;
rlm@1:       break;
rlm@1:     default:
rlm@1:       mt = G(L)->mt[ttype(o)];
rlm@1:   }
rlm@1:   return (mt ? luaH_getstr(mt, G(L)->tmname[event]) : luaO_nilobject);
rlm@1: }
rlm@1: