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-rw-r--r--lua-5.3.5/lstate.c347
1 files changed, 347 insertions, 0 deletions
diff --git a/lua-5.3.5/lstate.c b/lua-5.3.5/lstate.c
new file mode 100644
index 0000000..c1a7664
--- /dev/null
+++ b/lua-5.3.5/lstate.c
@@ -0,0 +1,347 @@
+/*
+** $Id: lstate.c,v 2.133.1.1 2017/04/19 17:39:34 roberto Exp $
+** Global State
+** See Copyright Notice in lua.h
+*/
+
+#define lstate_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+#if !defined(LUAI_GCPAUSE)
+#define LUAI_GCPAUSE 200 /* 200% */
+#endif
+
+#if !defined(LUAI_GCMUL)
+#define LUAI_GCMUL 200 /* GC runs 'twice the speed' of memory allocation */
+#endif
+
+
+/*
+** a macro to help the creation of a unique random seed when a state is
+** created; the seed is used to randomize hashes.
+*/
+#if !defined(luai_makeseed)
+#include <time.h>
+#define luai_makeseed() cast(unsigned int, time(NULL))
+#endif
+
+
+
+/*
+** thread state + extra space
+*/
+typedef struct LX {
+ lu_byte extra_[LUA_EXTRASPACE];
+ lua_State l;
+} LX;
+
+
+/*
+** Main thread combines a thread state and the global state
+*/
+typedef struct LG {
+ LX l;
+ global_State g;
+} LG;
+
+
+
+#define fromstate(L) (cast(LX *, cast(lu_byte *, (L)) - offsetof(LX, l)))
+
+
+/*
+** Compute an initial seed as random as possible. Rely on Address Space
+** Layout Randomization (if present) to increase randomness..
+*/
+#define addbuff(b,p,e) \
+ { size_t t = cast(size_t, e); \
+ memcpy(b + p, &t, sizeof(t)); p += sizeof(t); }
+
+static unsigned int makeseed (lua_State *L) {
+ char buff[4 * sizeof(size_t)];
+ unsigned int h = luai_makeseed();
+ int p = 0;
+ addbuff(buff, p, L); /* heap variable */
+ addbuff(buff, p, &h); /* local variable */
+ addbuff(buff, p, luaO_nilobject); /* global variable */
+ addbuff(buff, p, &lua_newstate); /* public function */
+ lua_assert(p == sizeof(buff));
+ return luaS_hash(buff, p, h);
+}
+
+
+/*
+** set GCdebt to a new value keeping the value (totalbytes + GCdebt)
+** invariant (and avoiding underflows in 'totalbytes')
+*/
+void luaE_setdebt (global_State *g, l_mem debt) {
+ l_mem tb = gettotalbytes(g);
+ lua_assert(tb > 0);
+ if (debt < tb - MAX_LMEM)
+ debt = tb - MAX_LMEM; /* will make 'totalbytes == MAX_LMEM' */
+ g->totalbytes = tb - debt;
+ g->GCdebt = debt;
+}
+
+
+CallInfo *luaE_extendCI (lua_State *L) {
+ CallInfo *ci = luaM_new(L, CallInfo);
+ lua_assert(L->ci->next == NULL);
+ L->ci->next = ci;
+ ci->previous = L->ci;
+ ci->next = NULL;
+ L->nci++;
+ return ci;
+}
+
+
+/*
+** free all CallInfo structures not in use by a thread
+*/
+void luaE_freeCI (lua_State *L) {
+ CallInfo *ci = L->ci;
+ CallInfo *next = ci->next;
+ ci->next = NULL;
+ while ((ci = next) != NULL) {
+ next = ci->next;
+ luaM_free(L, ci);
+ L->nci--;
+ }
+}
+
+
+/*
+** free half of the CallInfo structures not in use by a thread
+*/
+void luaE_shrinkCI (lua_State *L) {
+ CallInfo *ci = L->ci;
+ CallInfo *next2; /* next's next */
+ /* while there are two nexts */
+ while (ci->next != NULL && (next2 = ci->next->next) != NULL) {
+ luaM_free(L, ci->next); /* free next */
+ L->nci--;
+ ci->next = next2; /* remove 'next' from the list */
+ next2->previous = ci;
+ ci = next2; /* keep next's next */
+ }
+}
+
+
+static void stack_init (lua_State *L1, lua_State *L) {
+ int i; CallInfo *ci;
+ /* initialize stack array */
+ L1->stack = luaM_newvector(L, BASIC_STACK_SIZE, TValue);
+ L1->stacksize = BASIC_STACK_SIZE;
+ for (i = 0; i < BASIC_STACK_SIZE; i++)
+ setnilvalue(L1->stack + i); /* erase new stack */
+ L1->top = L1->stack;
+ L1->stack_last = L1->stack + L1->stacksize - EXTRA_STACK;
+ /* initialize first ci */
+ ci = &L1->base_ci;
+ ci->next = ci->previous = NULL;
+ ci->callstatus = 0;
+ ci->func = L1->top;
+ setnilvalue(L1->top++); /* 'function' entry for this 'ci' */
+ ci->top = L1->top + LUA_MINSTACK;
+ L1->ci = ci;
+}
+
+
+static void freestack (lua_State *L) {
+ if (L->stack == NULL)
+ return; /* stack not completely built yet */
+ L->ci = &L->base_ci; /* free the entire 'ci' list */
+ luaE_freeCI(L);
+ lua_assert(L->nci == 0);
+ luaM_freearray(L, L->stack, L->stacksize); /* free stack array */
+}
+
+
+/*
+** Create registry table and its predefined values
+*/
+static void init_registry (lua_State *L, global_State *g) {
+ TValue temp;
+ /* create registry */
+ Table *registry = luaH_new(L);
+ sethvalue(L, &g->l_registry, registry);
+ luaH_resize(L, registry, LUA_RIDX_LAST, 0);
+ /* registry[LUA_RIDX_MAINTHREAD] = L */
+ setthvalue(L, &temp, L); /* temp = L */
+ luaH_setint(L, registry, LUA_RIDX_MAINTHREAD, &temp);
+ /* registry[LUA_RIDX_GLOBALS] = table of globals */
+ sethvalue(L, &temp, luaH_new(L)); /* temp = new table (global table) */
+ luaH_setint(L, registry, LUA_RIDX_GLOBALS, &temp);
+}
+
+
+/*
+** open parts of the state that may cause memory-allocation errors.
+** ('g->version' != NULL flags that the state was completely build)
+*/
+static void f_luaopen (lua_State *L, void *ud) {
+ global_State *g = G(L);
+ UNUSED(ud);
+ stack_init(L, L); /* init stack */
+ init_registry(L, g);
+ luaS_init(L);
+ luaT_init(L);
+ luaX_init(L);
+ g->gcrunning = 1; /* allow gc */
+ g->version = lua_version(NULL);
+ luai_userstateopen(L);
+}
+
+
+/*
+** preinitialize a thread with consistent values without allocating
+** any memory (to avoid errors)
+*/
+static void preinit_thread (lua_State *L, global_State *g) {
+ G(L) = g;
+ L->stack = NULL;
+ L->ci = NULL;
+ L->nci = 0;
+ L->stacksize = 0;
+ L->twups = L; /* thread has no upvalues */
+ L->errorJmp = NULL;
+ L->nCcalls = 0;
+ L->hook = NULL;
+ L->hookmask = 0;
+ L->basehookcount = 0;
+ L->allowhook = 1;
+ resethookcount(L);
+ L->openupval = NULL;
+ L->nny = 1;
+ L->status = LUA_OK;
+ L->errfunc = 0;
+}
+
+
+static void close_state (lua_State *L) {
+ global_State *g = G(L);
+ luaF_close(L, L->stack); /* close all upvalues for this thread */
+ luaC_freeallobjects(L); /* collect all objects */
+ if (g->version) /* closing a fully built state? */
+ luai_userstateclose(L);
+ luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size);
+ freestack(L);
+ lua_assert(gettotalbytes(g) == sizeof(LG));
+ (*g->frealloc)(g->ud, fromstate(L), sizeof(LG), 0); /* free main block */
+}
+
+
+LUA_API lua_State *lua_newthread (lua_State *L) {
+ global_State *g = G(L);
+ lua_State *L1;
+ lua_lock(L);
+ luaC_checkGC(L);
+ /* create new thread */
+ L1 = &cast(LX *, luaM_newobject(L, LUA_TTHREAD, sizeof(LX)))->l;
+ L1->marked = luaC_white(g);
+ L1->tt = LUA_TTHREAD;
+ /* link it on list 'allgc' */
+ L1->next = g->allgc;
+ g->allgc = obj2gco(L1);
+ /* anchor it on L stack */
+ setthvalue(L, L->top, L1);
+ api_incr_top(L);
+ preinit_thread(L1, g);
+ L1->hookmask = L->hookmask;
+ L1->basehookcount = L->basehookcount;
+ L1->hook = L->hook;
+ resethookcount(L1);
+ /* initialize L1 extra space */
+ memcpy(lua_getextraspace(L1), lua_getextraspace(g->mainthread),
+ LUA_EXTRASPACE);
+ luai_userstatethread(L, L1);
+ stack_init(L1, L); /* init stack */
+ lua_unlock(L);
+ return L1;
+}
+
+
+void luaE_freethread (lua_State *L, lua_State *L1) {
+ LX *l = fromstate(L1);
+ luaF_close(L1, L1->stack); /* close all upvalues for this thread */
+ lua_assert(L1->openupval == NULL);
+ luai_userstatefree(L, L1);
+ freestack(L1);
+ luaM_free(L, l);
+}
+
+
+LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
+ int i;
+ lua_State *L;
+ global_State *g;
+ LG *l = cast(LG *, (*f)(ud, NULL, LUA_TTHREAD, sizeof(LG)));
+ if (l == NULL) return NULL;
+ L = &l->l.l;
+ g = &l->g;
+ L->next = NULL;
+ L->tt = LUA_TTHREAD;
+ g->currentwhite = bitmask(WHITE0BIT);
+ L->marked = luaC_white(g);
+ preinit_thread(L, g);
+ g->frealloc = f;
+ g->ud = ud;
+ g->mainthread = L;
+ g->seed = makeseed(L);
+ g->gcrunning = 0; /* no GC while building state */
+ g->GCestimate = 0;
+ g->strt.size = g->strt.nuse = 0;
+ g->strt.hash = NULL;
+ setnilvalue(&g->l_registry);
+ g->panic = NULL;
+ g->version = NULL;
+ g->gcstate = GCSpause;
+ g->gckind = KGC_NORMAL;
+ g->allgc = g->finobj = g->tobefnz = g->fixedgc = NULL;
+ g->sweepgc = NULL;
+ g->gray = g->grayagain = NULL;
+ g->weak = g->ephemeron = g->allweak = NULL;
+ g->twups = NULL;
+ g->totalbytes = sizeof(LG);
+ g->GCdebt = 0;
+ g->gcfinnum = 0;
+ g->gcpause = LUAI_GCPAUSE;
+ g->gcstepmul = LUAI_GCMUL;
+ for (i=0; i < LUA_NUMTAGS; i++) g->mt[i] = NULL;
+ if (luaD_rawrunprotected(L, f_luaopen, NULL) != LUA_OK) {
+ /* memory allocation error: free partial state */
+ close_state(L);
+ L = NULL;
+ }
+ return L;
+}
+
+
+LUA_API void lua_close (lua_State *L) {
+ L = G(L)->mainthread; /* only the main thread can be closed */
+ lua_lock(L);
+ close_state(L);
+}
+
+