]>
Commit | Line | Data |
---|---|---|
d99a0153 CW |
1 | /* |
2 | ** $Id: ltm.c,v 2.14.1.1 2013/04/12 18:48:47 roberto Exp $ | |
3 | ** Tag methods | |
4 | ** See Copyright Notice in lua.h | |
5 | */ | |
6 | ||
7 | ||
8 | #define ltm_c | |
9 | #define LUA_CORE | |
10 | ||
11 | #include <sys/lua/lua.h> | |
12 | ||
13 | #include "lobject.h" | |
14 | #include "lstate.h" | |
15 | #include "lstring.h" | |
16 | #include "ltable.h" | |
17 | #include "ltm.h" | |
18 | ||
19 | ||
20 | static const char udatatypename[] = "userdata"; | |
21 | ||
22 | LUAI_DDEF const char *const luaT_typenames_[LUA_TOTALTAGS] = { | |
23 | "no value", | |
24 | "nil", "boolean", udatatypename, "number", | |
25 | "string", "table", "function", udatatypename, "thread", | |
26 | "proto", "upval" /* these last two cases are used for tests only */ | |
27 | }; | |
28 | ||
29 | ||
30 | void luaT_init (lua_State *L) { | |
31 | static const char *const luaT_eventname[] = { /* ORDER TM */ | |
32 | "__index", "__newindex", | |
33 | "__gc", "__mode", "__len", "__eq", | |
34 | "__add", "__sub", "__mul", "__div", "__mod", | |
35 | "__pow", "__unm", "__lt", "__le", | |
36 | "__concat", "__call" | |
37 | }; | |
38 | int i; | |
39 | for (i=0; i<TM_N; i++) { | |
40 | G(L)->tmname[i] = luaS_new(L, luaT_eventname[i]); | |
41 | luaS_fix(G(L)->tmname[i]); /* never collect these names */ | |
42 | } | |
43 | } | |
44 | ||
45 | ||
46 | /* | |
47 | ** function to be used with macro "fasttm": optimized for absence of | |
48 | ** tag methods | |
49 | */ | |
50 | const TValue *luaT_gettm (Table *events, TMS event, TString *ename) { | |
51 | const TValue *tm = luaH_getstr(events, ename); | |
52 | lua_assert(event <= TM_EQ); | |
53 | if (ttisnil(tm)) { /* no tag method? */ | |
54 | events->flags |= cast_byte(1u<<event); /* cache this fact */ | |
55 | return NULL; | |
56 | } | |
57 | else return tm; | |
58 | } | |
59 | ||
60 | ||
61 | const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) { | |
62 | Table *mt; | |
63 | switch (ttypenv(o)) { | |
64 | case LUA_TTABLE: | |
65 | mt = hvalue(o)->metatable; | |
66 | break; | |
67 | case LUA_TUSERDATA: | |
68 | mt = uvalue(o)->metatable; | |
69 | break; | |
70 | default: | |
71 | mt = G(L)->mt[ttypenv(o)]; | |
72 | } | |
73 | return (mt ? luaH_getstr(mt, G(L)->tmname[event]) : luaO_nilobject); | |
74 | } |