Import lua 5.3.0.vendor/lua/5.3.0

1 files changed, 346 insertions, 0 deletions

diff --git a/src/lstate.c b/src/lstate.c
new file mode 100644
index 000000000000..ff6b02d36ae0
--- /dev/null
+++ b/src/lstate.c
@@ -0,0 +1,346 @@
+/*
+** $Id: lstate.c,v 2.127 2014/11/02 19:33:33 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
+
+
+#define MEMERRMSG	"not enough memory"
+
+
+/*
+** 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(buff + 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
+*/
+void luaE_setdebt (global_State *g, l_mem debt) {
+  g->totalbytes -= (debt - g->GCdebt);
+  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;
+  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);
+  }
+}
+
+
+/*
+** free half of the CallInfo structures not in use by a thread
+*/
+void luaE_shrinkCI (lua_State *L) {
+  CallInfo *ci = L->ci;
+  while (ci->next != NULL) {  /* while there is 'next' */
+    CallInfo *next2 = ci->next->next;  /* next's next */
+    if (next2 == NULL) break;
+    luaM_free(L, ci->next);  /* remove next */
+    ci->next = next2;  /* remove 'next' from the list */
+    next2->previous = ci;
+    ci = next2;
+  }
+}
+
+
+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);
+  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_resize(L, MINSTRTABSIZE);  /* initial size of string table */
+  luaT_init(L);
+  luaX_init(L);
+  /* pre-create memory-error message */
+  g->memerrmsg = luaS_newliteral(L, MEMERRMSG);
+  luaC_fix(L, obj2gco(g->memerrmsg));  /* it should never be collected */
+  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->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);
+  luaZ_freebuffer(L, &g->buff);
+  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);
+  luaZ_initbuffer(L, &g->buff);
+  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);
+}
+
+