diff options
Diffstat (limited to 'plugins/MirLua/src/lua/ltm.c')
| -rw-r--r-- | plugins/MirLua/src/lua/ltm.c | 143 | 
1 files changed, 143 insertions, 0 deletions
diff --git a/plugins/MirLua/src/lua/ltm.c b/plugins/MirLua/src/lua/ltm.c new file mode 100644 index 0000000000..25b46b17f9 --- /dev/null +++ b/plugins/MirLua/src/lua/ltm.c @@ -0,0 +1,143 @@ +/* +** $Id: ltm.c,v 2.33 2014/11/21 12:15:57 roberto Exp $ +** Tag methods +** See Copyright Notice in lua.h +*/ + +#define ltm_c +#define LUA_CORE + +#include "lprefix.h" + + +#include <string.h> + +#include "lua.h" + +#include "ldebug.h" +#include "ldo.h"  +#include "lobject.h" +#include "lstate.h" +#include "lstring.h" +#include "ltable.h" +#include "ltm.h" +#include "lvm.h" + + +static const char udatatypename[] = "userdata"; + +LUAI_DDEF const char *const luaT_typenames_[LUA_TOTALTAGS] = { +  "no value", +  "nil", "boolean", udatatypename, "number", +  "string", "table", "function", udatatypename, "thread", +  "proto" /* this last case is used for tests only */ +}; + + +void luaT_init (lua_State *L) { +  static const char *const luaT_eventname[] = {  /* ORDER TM */ +    "__index", "__newindex", +    "__gc", "__mode", "__len", "__eq", +    "__add", "__sub", "__mul", "__mod", "__pow", +    "__div", "__idiv", +    "__band", "__bor", "__bxor", "__shl", "__shr", +    "__unm", "__bnot", "__lt", "__le", +    "__concat", "__call" +  }; +  int i; +  for (i=0; i<TM_N; i++) { +    G(L)->tmname[i] = luaS_new(L, luaT_eventname[i]); +    luaC_fix(L, obj2gco(G(L)->tmname[i]));  /* never collect these names */ +  } +} + + +/* +** function to be used with macro "fasttm": optimized for absence of +** tag methods +*/ +const TValue *luaT_gettm (Table *events, TMS event, TString *ename) { +  const TValue *tm = luaH_getstr(events, ename); +  lua_assert(event <= TM_EQ); +  if (ttisnil(tm)) {  /* no tag method? */ +    events->flags |= cast_byte(1u<<event);  /* cache this fact */ +    return NULL; +  } +  else return tm; +} + + +const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) { +  Table *mt; +  switch (ttnov(o)) { +    case LUA_TTABLE: +      mt = hvalue(o)->metatable; +      break; +    case LUA_TUSERDATA: +      mt = uvalue(o)->metatable; +      break; +    default: +      mt = G(L)->mt[ttnov(o)]; +  } +  return (mt ? luaH_getstr(mt, G(L)->tmname[event]) : luaO_nilobject); +} + + +void luaT_callTM (lua_State *L, const TValue *f, const TValue *p1, +                  const TValue *p2, TValue *p3, int hasres) { +  ptrdiff_t result = savestack(L, p3); +  setobj2s(L, L->top++, f);  /* push function (assume EXTRA_STACK) */ +  setobj2s(L, L->top++, p1);  /* 1st argument */ +  setobj2s(L, L->top++, p2);  /* 2nd argument */ +  if (!hasres)  /* no result? 'p3' is third argument */ +    setobj2s(L, L->top++, p3);  /* 3rd argument */ +  /* metamethod may yield only when called from Lua code */ +  luaD_call(L, L->top - (4 - hasres), hasres, isLua(L->ci)); +  if (hasres) {  /* if has result, move it to its place */ +    p3 = restorestack(L, result); +    setobjs2s(L, p3, --L->top); +  } +} + + +int luaT_callbinTM (lua_State *L, const TValue *p1, const TValue *p2, +                    StkId res, TMS event) { +  const TValue *tm = luaT_gettmbyobj(L, p1, event);  /* try first operand */ +  if (ttisnil(tm)) +    tm = luaT_gettmbyobj(L, p2, event);  /* try second operand */ +  if (ttisnil(tm)) return 0; +  luaT_callTM(L, tm, p1, p2, res, 1); +  return 1; +} + + +void luaT_trybinTM (lua_State *L, const TValue *p1, const TValue *p2, +                    StkId res, TMS event) { +  if (!luaT_callbinTM(L, p1, p2, res, event)) { +    switch (event) { +      case TM_CONCAT: +        luaG_concaterror(L, p1, p2); +      case TM_BAND: case TM_BOR: case TM_BXOR: +      case TM_SHL: case TM_SHR: case TM_BNOT: { +        lua_Number dummy; +        if (tonumber(p1, &dummy) && tonumber(p2, &dummy)) +          luaG_tointerror(L, p1, p2); +        else +          luaG_opinterror(L, p1, p2, "perform bitwise operation on"); +        /* else go through */ +      } +      default: +        luaG_opinterror(L, p1, p2, "perform arithmetic on"); +    } +  } +} + + +int luaT_callorderTM (lua_State *L, const TValue *p1, const TValue *p2, +                      TMS event) { +  if (!luaT_callbinTM(L, p1, p2, L->top, event)) +    return -1;  /* no metamethod */ +  else +    return !l_isfalse(L->top); +} +  | 
