From af850484a9e01b46b04e4c666f9a9e91308d81c7 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 1 Dec 2003 16:22:56 -0200
Subject: default metatable can be NULL
---
lapi.c | 19 ++++++++++++-------
lgc.c | 9 +++++----
lstate.c | 7 +------
lstate.h | 6 +-----
lstring.c | 4 ++--
ltable.c | 4 ++--
ltm.c | 13 ++++++++-----
ltm.h | 6 +++---
8 files changed, 34 insertions(+), 34 deletions(-)
diff --git a/lapi.c b/lapi.c
index c078160a..5c974e41 100644
--- a/lapi.c
+++ b/lapi.c
@@ -1,5 +1,5 @@
/*
-** $Id: lapi.c,v 1.248 2003/10/20 12:25:23 roberto Exp roberto $
+** $Id: lapi.c,v 1.249 2003/10/20 17:42:41 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
@@ -555,7 +555,7 @@ LUA_API int lua_getmetatable (lua_State *L, int objindex) {
mt = uvalue(obj)->uv.metatable;
break;
}
- if (mt == NULL || mt == hvalue(defaultmeta(L)))
+ if (mt == NULL)
res = 0;
else {
sethvalue(L->top, mt);
@@ -634,21 +634,26 @@ LUA_API void lua_rawseti (lua_State *L, int idx, int n) {
LUA_API int lua_setmetatable (lua_State *L, int objindex) {
- TObject *obj, *mt;
+ TObject *obj;
+ Table *mt;
int res = 1;
lua_lock(L);
api_checknelems(L, 1);
obj = luaA_index(L, objindex);
api_checkvalidindex(L, obj);
- mt = (!ttisnil(L->top - 1)) ? L->top - 1 : defaultmeta(L);
- api_check(L, ttistable(mt));
+ if (ttisnil(L->top - 1))
+ mt = NULL;
+ else {
+ api_check(L, ttistable(L->top - 1));
+ mt = hvalue(L->top - 1);
+ }
switch (ttype(obj)) {
case LUA_TTABLE: {
- hvalue(obj)->metatable = hvalue(mt); /* write barrier */
+ hvalue(obj)->metatable = mt; /* write barrier */
break;
}
case LUA_TUSERDATA: {
- uvalue(obj)->uv.metatable = hvalue(mt); /* write barrier */
+ uvalue(obj)->uv.metatable = mt; /* write barrier */
break;
}
default: {
diff --git a/lgc.c b/lgc.c
index cb9fa289..f8fdcb4c 100644
--- a/lgc.c
+++ b/lgc.c
@@ -1,5 +1,5 @@
/*
-** $Id: lgc.c,v 1.180 2003/11/19 19:41:57 roberto Exp roberto $
+** $Id: lgc.c,v 1.181 2003/12/01 16:33:30 roberto Exp roberto $
** Garbage Collector
** See Copyright Notice in lua.h
*/
@@ -114,8 +114,9 @@ static void reallymarkobject (global_State *g, GCObject *o) {
return;
}
case LUA_TUSERDATA: {
+ Table *mt = gcotou(o)->uv.metatable;
white2black(o); /* userdata do not go to gray list */
- markobject(g, gcotou(o)->uv.metatable);
+ if (mt) markobject(g, mt);
return;
}
case LUA_TFUNCTION: {
@@ -191,7 +192,8 @@ static void traversetable (global_State *g, Table *h) {
int weakkey = 0;
int weakvalue = 0;
const TObject *mode;
- markobject(g, h->metatable);
+ if (h->metatable)
+ markobject(g, h->metatable);
lua_assert(h->lsizenode || h->node == g->dummynode);
mode = gfasttm(g, h->metatable, TM_MODE);
if (mode && ttisstring(mode)) { /* is there a weak mode? */
@@ -534,7 +536,6 @@ static void markroot (lua_State *L) {
g->weak = NULL;
makewhite(valtogco(g->mainthread));
markobject(g, g->mainthread);
- markvalue(g, defaultmeta(L));
markvalue(g, registry(L));
if (L != g->mainthread) /* another thread is running? */
markobject(g, L); /* cannot collect it */
diff --git a/lstate.c b/lstate.c
index 49c71719..40e29c6f 100644
--- a/lstate.c
+++ b/lstate.c
@@ -1,5 +1,5 @@
/*
-** $Id: lstate.c,v 1.128 2003/11/18 14:55:11 roberto Exp roberto $
+** $Id: lstate.c,v 1.129 2003/12/01 16:33:30 roberto Exp roberto $
** Global State
** See Copyright Notice in lua.h
*/
@@ -76,10 +76,6 @@ static void freestack (lua_State *L, lua_State *L1) {
static void f_luaopen (lua_State *L, void *ud) {
UNUSED(ud);
stack_init(L, L); /* init stack */
- /* create default meta table with a dummy table, and then close the loop */
- defaultmeta(L)->tt = LUA_TTABLE;
- sethvalue(defaultmeta(L), luaH_new(L, 0, 0));
- hvalue(defaultmeta(L))->metatable = hvalue(defaultmeta(L));
sethvalue(gt(L), luaH_new(L, 0, 4)); /* table of globals */
sethvalue(registry(L), luaH_new(L, 4, 4)); /* registry */
luaS_resize(L, MINSTRTABSIZE); /* initial size of string table */
@@ -161,7 +157,6 @@ LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
g->strt.size = 0;
g->strt.nuse = 0;
g->strt.hash = NULL;
- setnilvalue(defaultmeta(L));
setnilvalue(registry(L));
luaZ_initbuffer(L, &g->buff);
g->panic = NULL;
diff --git a/lstate.h b/lstate.h
index ed46fb1f..a62bcef8 100644
--- a/lstate.h
+++ b/lstate.h
@@ -1,5 +1,5 @@
/*
-** $Id: lstate.h,v 1.113 2003/11/18 14:55:11 roberto Exp roberto $
+** $Id: lstate.h,v 1.114 2003/12/01 16:33:30 roberto Exp roberto $
** Global State
** See Copyright Notice in lua.h
*/
@@ -42,9 +42,6 @@
struct lua_longjmp; /* defined in ldo.c */
-/* default meta table (both for tables and udata) */
-#define defaultmeta(L) (&G(L)->_defaultmeta)
-
/* table of globals */
#define gt(L) (&L->_gt)
@@ -113,7 +110,6 @@ typedef struct global_State {
lu_mem nblocks; /* number of `bytes' currently allocated */
lua_CFunction panic; /* to be called in unprotected errors */
TObject _registry;
- TObject _defaultmeta;
struct lua_State *mainthread;
Node dummynode[1]; /* common node array for all empty tables */
TString *tmname[TM_N]; /* array with tag-method names */
diff --git a/lstring.c b/lstring.c
index 1b0a0050..e7e84609 100644
--- a/lstring.c
+++ b/lstring.c
@@ -1,5 +1,5 @@
/*
-** $Id: lstring.c,v 1.79 2003/04/28 19:26:16 roberto Exp roberto $
+** $Id: lstring.c,v 1.80 2003/11/17 19:50:05 roberto Exp roberto $
** String table (keeps all strings handled by Lua)
** See Copyright Notice in lua.h
*/
@@ -94,7 +94,7 @@ Udata *luaS_newudata (lua_State *L, size_t s) {
u->uv.marked = 0; /* is not finalized */
u->uv.tt = LUA_TUSERDATA;
u->uv.len = s;
- u->uv.metatable = hvalue(defaultmeta(L));
+ u->uv.metatable = NULL;
/* chain it on udata list */
u->uv.next = G(L)->rootudata;
G(L)->rootudata = valtogco(u);
diff --git a/ltable.c b/ltable.c
index 8b55a1f5..ccd333f3 100644
--- a/ltable.c
+++ b/ltable.c
@@ -1,5 +1,5 @@
/*
-** $Id: ltable.c,v 1.135 2003/08/26 12:04:13 roberto Exp roberto $
+** $Id: ltable.c,v 1.136 2003/11/27 18:05:14 roberto Exp roberto $
** Lua tables (hash)
** See Copyright Notice in lua.h
*/
@@ -328,7 +328,7 @@ static void rehash (lua_State *L, Table *t) {
Table *luaH_new (lua_State *L, int narray, int lnhash) {
Table *t = luaM_new(L, Table);
luaC_link(L, valtogco(t), LUA_TTABLE);
- t->metatable = hvalue(defaultmeta(L));
+ t->metatable = NULL;
t->flags = cast(lu_byte, ~0);
/* temporary values (kept only if some malloc fails) */
t->array = NULL;
diff --git a/ltm.c b/ltm.c
index 5687e28b..b8fbb1f9 100644
--- a/ltm.c
+++ b/ltm.c
@@ -1,5 +1,5 @@
/*
-** $Id: ltm.c,v 1.105 2002/12/04 17:38:31 roberto Exp roberto $
+** $Id: ltm.c,v 1.106 2003/04/03 13:35:34 roberto Exp roberto $
** Tag methods
** See Copyright Notice in lua.h
*/
@@ -57,14 +57,17 @@ const TObject *luaT_gettm (Table *events, TMS event, TString *ename) {
const TObject *luaT_gettmbyobj (lua_State *L, const TObject *o, TMS event) {
- TString *ename = G(L)->tmname[event];
+ Table *mt;
switch (ttype(o)) {
case LUA_TTABLE:
- return luaH_getstr(hvalue(o)->metatable, ename);
+ mt = hvalue(o)->metatable;
+ break;
case LUA_TUSERDATA:
- return luaH_getstr(uvalue(o)->uv.metatable, ename);
+ mt = uvalue(o)->uv.metatable;
+ break;
default:
- return &luaO_nilobject;
+ mt = NULL;
}
+ return (mt ? luaH_getstr(mt, G(L)->tmname[event]) : &luaO_nilobject);
}
diff --git a/ltm.h b/ltm.h
index 4c56a093..d40bf6c5 100644
--- a/ltm.h
+++ b/ltm.h
@@ -1,5 +1,5 @@
/*
-** $Id: ltm.h,v 1.40 2002/09/19 20:12:47 roberto Exp roberto $
+** $Id: ltm.h,v 1.41 2002/11/14 11:51:50 roberto Exp roberto $
** Tag methods
** See Copyright Notice in lua.h
*/
@@ -36,8 +36,8 @@ typedef enum {
-#define gfasttm(g,et,e) \
- (((et)->flags & (1u<<(e))) ? NULL : luaT_gettm(et, e, (g)->tmname[e]))
+#define gfasttm(g,et,e) ((et) == NULL ? NULL : \
+ ((et)->flags & (1u<<(e))) ? NULL : luaT_gettm(et, e, (g)->tmname[e]))
#define fasttm(l,et,e) gfasttm(G(l), et, e)
--
cgit v1.2.3-55-g6feb