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-rw-r--r--lua-5.3.5/ltm.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/lua-5.3.5/ltm.c b/lua-5.3.5/ltm.c
new file mode 100644
index 0000000..0e7c713
--- /dev/null
+++ b/lua-5.3.5/ltm.c
@@ -0,0 +1,165 @@
+/*
+** $Id: ltm.c,v 2.38.1.1 2017/04/19 17:39:34 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_getshortstr(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_getshortstr(mt, G(L)->tmname[event]) : luaO_nilobject);
+}
+
+
+/*
+** Return the name of the type of an object. For tables and userdata
+** with metatable, use their '__name' metafield, if present.
+*/
+const char *luaT_objtypename (lua_State *L, const TValue *o) {
+ Table *mt;
+ if ((ttistable(o) && (mt = hvalue(o)->metatable) != NULL) ||
+ (ttisfulluserdata(o) && (mt = uvalue(o)->metatable) != NULL)) {
+ const TValue *name = luaH_getshortstr(mt, luaS_new(L, "__name"));
+ if (ttisstring(name)) /* is '__name' a string? */
+ return getstr(tsvalue(name)); /* use it as type name */
+ }
+ return ttypename(ttnov(o)); /* else use standard type name */
+}
+
+
+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);
+ StkId func = L->top;
+ setobj2s(L, func, f); /* push function (assume EXTRA_STACK) */
+ setobj2s(L, func + 1, p1); /* 1st argument */
+ setobj2s(L, func + 2, p2); /* 2nd argument */
+ L->top += 3;
+ if (!hasres) /* no result? 'p3' is third argument */
+ setobj2s(L, L->top++, p3); /* 3rd argument */
+ /* metamethod may yield only when called from Lua code */
+ if (isLua(L->ci))
+ luaD_call(L, func, hasres);
+ else
+ luaD_callnoyield(L, func, hasres);
+ 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);
+ /* call never returns, but to avoid warnings: *//* FALLTHROUGH */
+ 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");
+ }
+ /* calls never return, but to avoid warnings: *//* FALLTHROUGH */
+ 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);
+}
+