lua/lstate.c

153 lines
3.9 KiB
C

/*
** $Id: lstate.c,v 1.55 2001/01/26 11:45:51 roberto Exp roberto $
** Global State
** See Copyright Notice in lua.h
*/
#include <stdio.h>
#include "lua.h"
#include "ldo.h"
#include "lgc.h"
#include "llex.h"
#include "lmem.h"
#include "lstate.h"
#include "lstring.h"
#include "ltable.h"
#include "ltm.h"
struct Sopen {
int stacksize;
lua_State *L;
};
static void close_state (lua_State *L, lua_State *OL);
/*
** initialize ref array and registry
*/
#define INIT_REFSIZE 4
static void ref_init (lua_State *L) {
G(L)->refArray = luaM_newvector(L, INIT_REFSIZE, struct Ref);
G(L)->sizeref = INIT_REFSIZE;
sethvalue(&G(L)->refArray[0].o, luaH_new(L, 0));
G(L)->refArray[0].st = LOCK;
G(L)->nref = 1;
}
/*
** open parts that may cause memory-allocation errors
*/
static void f_luaopen (lua_State *L, void *ud) {
struct Sopen *so = (struct Sopen *)ud;
if (so->stacksize == 0)
so->stacksize = DEFAULT_STACK_SIZE;
else
so->stacksize += LUA_MINSTACK;
if (so->L != NULL) { /* shared global state? */
L->G = G(so->L);
L->gt = so->L->gt; /* share table of globals */
so->L->next->previous = L; /* insert L into linked list */
L->next = so->L->next;
so->L->next = L;
L->previous = so->L;
luaD_init(L, so->stacksize); /* init stack */
}
else { /* create a new global state */
L->G = luaM_new(L, global_State);
G(L)->strt.size = G(L)->udt.size = 0;
G(L)->strt.nuse = G(L)->udt.nuse = 0;
G(L)->strt.hash = G(L)->udt.hash = NULL;
G(L)->Mbuffer = NULL;
G(L)->Mbuffsize = 0;
G(L)->rootproto = NULL;
G(L)->rootcl = NULL;
G(L)->roottable = NULL;
G(L)->TMtable = NULL;
G(L)->sizeTM = 0;
G(L)->ntag = 0;
G(L)->refArray = NULL;
G(L)->nref = 0;
G(L)->sizeref = 0;
G(L)->refFree = NONEXT;
G(L)->nblocks = sizeof(lua_State) + sizeof(global_State);
luaD_init(L, so->stacksize); /* init stack */
L->gt = luaH_new(L, 10); /* table of globals */
G(L)->type2tag = luaH_new(L, 10);
luaS_init(L);
luaX_init(L);
luaT_init(L);
ref_init(L);
G(L)->GCthreshold = 4*G(L)->nblocks;
}
}
LUA_API lua_State *lua_open (lua_State *OL, int stacksize) {
struct Sopen so;
lua_State *L;
if (OL) LUA_LOCK(OL);
L = luaM_new(OL, lua_State);
if (L) { /* allocation OK? */
L->G = NULL;
L->stack = NULL;
L->stacksize = 0;
L->errorJmp = NULL;
L->callhook = NULL;
L->linehook = NULL;
L->allowhooks = 1;
L->next = L->previous = L;
so.stacksize = stacksize;
so.L = OL;
if (luaD_runprotected(L, f_luaopen, &so) != 0) {
/* memory allocation error: free partial state */
close_state(L, OL);
L = NULL;
}
}
if (OL) LUA_UNLOCK(OL);
return L;
}
static void close_state (lua_State *L, lua_State *OL) {
if (OL != NULL) { /* are there other threads? */
lua_assert(L->previous != L);
L->previous->next = L->next;
L->next->previous = L->previous;
}
else if (G(L)) { /* last thread; close global state */
luaC_collect(L, 1); /* collect all elements */
lua_assert(G(L)->rootproto == NULL);
lua_assert(G(L)->rootcl == NULL);
lua_assert(G(L)->roottable == NULL);
luaS_freeall(L);
luaM_freearray(L, G(L)->TMtable, G(L)->sizeTM, struct TM);
luaM_freearray(L, G(L)->refArray, G(L)->sizeref, struct Ref);
luaM_freearray(L, G(L)->Mbuffer, G(L)->Mbuffsize, char);
luaM_freelem(NULL, L->G, global_State);
}
luaM_freearray(OL, L->stack, L->stacksize, TObject);
luaM_freelem(OL, L, lua_State);
}
LUA_API void lua_close (lua_State *L) {
lua_State *OL;
lua_assert(L != lua_state || lua_gettop(L) == 0);
LUA_LOCK(L);
OL = L->next; /* any surviving thread (if there is one) */
if (OL == L) OL = NULL; /* no surviving threads */
close_state(L, OL);
if (OL) LUA_UNLOCK(OL); /* cannot unlock over a freed state */
lua_assert(L != lua_state || memdebug_numblocks == 0);
lua_assert(L != lua_state || memdebug_total == 0);
}