1/* $NetBSD$ */ 2 3/* 4** Id: lstate.c,v 2.36.1.2 2008/01/03 15:20:39 roberto Exp 5** Global State 6** See Copyright Notice in lua.h 7*/ 8 9 10#include <stddef.h> 11 12#define lstate_c 13#define LUA_CORE 14 15#include "lua.h" 16 17#include "ldebug.h" 18#include "ldo.h" 19#include "lfunc.h" 20#include "lgc.h" 21#include "llex.h" 22#include "lmem.h" 23#include "lstate.h" 24#include "lstring.h" 25#include "ltable.h" 26#include "ltm.h" 27 28 29#define state_size(x) (sizeof(x) + LUAI_EXTRASPACE) 30#define fromstate(l) (cast(lu_byte *, (l)) - LUAI_EXTRASPACE) 31#define tostate(l) (cast(lua_State *, cast(lu_byte *, l) + LUAI_EXTRASPACE)) 32 33 34/* 35** Main thread combines a thread state and the global state 36*/ 37typedef struct LG { 38 lua_State l; 39 global_State g; 40} LG; 41 42 43 44static void stack_init (lua_State *L1, lua_State *L) { 45 /* initialize CallInfo array */ 46 L1->base_ci = luaM_newvector(L, BASIC_CI_SIZE, CallInfo); 47 L1->ci = L1->base_ci; 48 L1->size_ci = BASIC_CI_SIZE; 49 L1->end_ci = L1->base_ci + L1->size_ci - 1; 50 /* initialize stack array */ 51 L1->stack = luaM_newvector(L, BASIC_STACK_SIZE + EXTRA_STACK, TValue); 52 L1->stacksize = BASIC_STACK_SIZE + EXTRA_STACK; 53 L1->top = L1->stack; 54 L1->stack_last = L1->stack+(L1->stacksize - EXTRA_STACK)-1; 55 /* initialize first ci */ 56 L1->ci->func = L1->top; 57 setnilvalue(L1->top++); /* `function' entry for this `ci' */ 58 L1->base = L1->ci->base = L1->top; 59 L1->ci->top = L1->top + LUA_MINSTACK; 60} 61 62 63static void freestack (lua_State *L, lua_State *L1) { 64 luaM_freearray(L, L1->base_ci, L1->size_ci, CallInfo); 65 luaM_freearray(L, L1->stack, L1->stacksize, TValue); 66} 67 68 69/* 70** open parts that may cause memory-allocation errors 71*/ 72static void f_luaopen (lua_State *L, void *ud) { 73 global_State *g = G(L); 74 UNUSED(ud); 75 stack_init(L, L); /* init stack */ 76 sethvalue(L, gt(L), luaH_new(L, 0, 2)); /* table of globals */ 77 sethvalue(L, registry(L), luaH_new(L, 0, 2)); /* registry */ 78 luaS_resize(L, MINSTRTABSIZE); /* initial size of string table */ 79 luaT_init(L); 80 luaX_init(L); 81 luaS_fix(luaS_newliteral(L, MEMERRMSG)); 82 g->GCthreshold = 4*g->totalbytes; 83} 84 85 86static void preinit_state (lua_State *L, global_State *g) { 87 G(L) = g; 88 L->stack = NULL; 89 L->stacksize = 0; 90 L->errorJmp = NULL; 91 L->hook = NULL; 92 L->hookmask = 0; 93 L->basehookcount = 0; 94 L->allowhook = 1; 95 resethookcount(L); 96 L->openupval = NULL; 97 L->size_ci = 0; 98 L->nCcalls = L->baseCcalls = 0; 99 L->status = 0; 100 L->base_ci = L->ci = NULL; 101 L->savedpc = NULL; 102 L->errfunc = 0; 103 setnilvalue(gt(L)); 104} 105 106 107static void close_state (lua_State *L) { 108 global_State *g = G(L); 109 luaF_close(L, L->stack); /* close all upvalues for this thread */ 110 luaC_freeall(L); /* collect all objects */ 111 lua_assert(g->rootgc == obj2gco(L)); 112 lua_assert(g->strt.nuse == 0); 113 luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size, TString *); 114 luaZ_freebuffer(L, &g->buff); 115 freestack(L, L); 116 lua_assert(g->totalbytes == sizeof(LG)); 117 (*g->frealloc)(g->ud, fromstate(L), state_size(LG), 0); 118} 119 120 121lua_State *luaE_newthread (lua_State *L) { 122 lua_State *L1 = tostate(luaM_malloc(L, state_size(lua_State))); 123 luaC_link(L, obj2gco(L1), LUA_TTHREAD); 124 preinit_state(L1, G(L)); 125 stack_init(L1, L); /* init stack */ 126 setobj2n(L, gt(L1), gt(L)); /* share table of globals */ 127 L1->hookmask = L->hookmask; 128 L1->basehookcount = L->basehookcount; 129 L1->hook = L->hook; 130 resethookcount(L1); 131 lua_assert(iswhite(obj2gco(L1))); 132 return L1; 133} 134 135 136void luaE_freethread (lua_State *L, lua_State *L1) { 137 luaF_close(L1, L1->stack); /* close all upvalues for this thread */ 138 lua_assert(L1->openupval == NULL); 139 luai_userstatefree(L1); 140 freestack(L, L1); 141 luaM_freemem(L, fromstate(L1), state_size(lua_State)); 142} 143 144 145LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) { 146 int i; 147 lua_State *L; 148 global_State *g; 149 void *l = (*f)(ud, NULL, 0, state_size(LG)); 150 if (l == NULL) return NULL; 151 L = tostate(l); 152 g = &((LG *)L)->g; 153 L->next = NULL; 154 L->tt = LUA_TTHREAD; 155 g->currentwhite = bit2mask(WHITE0BIT, FIXEDBIT); 156 L->marked = luaC_white(g); 157 set2bits(L->marked, FIXEDBIT, SFIXEDBIT); 158 preinit_state(L, g); 159 g->frealloc = f; 160 g->ud = ud; 161 g->mainthread = L; 162 g->uvhead.u.l.prev = &g->uvhead; 163 g->uvhead.u.l.next = &g->uvhead; 164 g->GCthreshold = 0; /* mark it as unfinished state */ 165 g->strt.size = 0; 166 g->strt.nuse = 0; 167 g->strt.hash = NULL; 168 setnilvalue(registry(L)); 169 luaZ_initbuffer(L, &g->buff); 170 g->panic = NULL; 171 g->gcstate = GCSpause; 172 g->rootgc = obj2gco(L); 173 g->sweepstrgc = 0; 174 g->sweepgc = &g->rootgc; 175 g->gray = NULL; 176 g->grayagain = NULL; 177 g->weak = NULL; 178 g->tmudata = NULL; 179 g->totalbytes = sizeof(LG); 180 g->gcpause = LUAI_GCPAUSE; 181 g->gcstepmul = LUAI_GCMUL; 182 g->gcdept = 0; 183 for (i=0; i<NUM_TAGS; i++) g->mt[i] = NULL; 184 if (luaD_rawrunprotected(L, f_luaopen, NULL) != 0) { 185 /* memory allocation error: free partial state */ 186 close_state(L); 187 L = NULL; 188 } 189 else 190 luai_userstateopen(L); 191 return L; 192} 193 194 195static void callallgcTM (lua_State *L, void *ud) { 196 UNUSED(ud); 197 luaC_callGCTM(L); /* call GC metamethods for all udata */ 198} 199 200 201LUA_API void lua_close (lua_State *L) { 202 L = G(L)->mainthread; /* only the main thread can be closed */ 203 lua_lock(L); 204 luaF_close(L, L->stack); /* close all upvalues for this thread */ 205 luaC_separateudata(L, 1); /* separate udata that have GC metamethods */ 206 L->errfunc = 0; /* no error function during GC metamethods */ 207 do { /* repeat until no more errors */ 208 L->ci = L->base_ci; 209 L->base = L->top = L->ci->base; 210 L->nCcalls = L->baseCcalls = 0; 211 } while (luaD_rawrunprotected(L, callallgcTM, NULL) != 0); 212 lua_assert(G(L)->tmudata == NULL); 213 luai_userstateclose(L); 214 close_state(L); 215} 216 217