/*** $Id: lstring.c,v 2.8 2005/12/22 16:19:56 roberto Exp $** String table (keeps all strings handled by Lua)** See Copyright Notice in lua.h*/#include <string.h>#define lstring_c#define LUA_CORE#include "lua.h"#include "lmem.h"#include "lobject.h"#include "lstate.h"#include "lstring.h"void luaS_resize (lua_State *L, int newsize) {  GCObject **newhash;  stringtable *tb;  int i;  if (G(L)->gcstate == GCSsweepstring)    return;  /* cannot resize during GC traverse */  newhash = luaM_newvector(L, newsize, GCObject *);  tb = &G(L)->strt;  for (i=0; i<newsize; i++) newhash[i] = NULL;  /* rehash */  for (i=0; i<tb->size; i++) {    GCObject *p = tb->hash[i];    while (p) {  /* for each node in the list */      GCObject *next = p->gch.next;  /* save next */      unsigned int h = gco2ts(p)->hash;      int h1 = lmod(h, newsize);  /* new position */      lua_assert(cast_int(h%newsize) == lmod(h, newsize));      p->gch.next = newhash[h1];  /* chain it */      newhash[h1] = p;      p = next;    }  }  luaM_freearray(L, tb->hash, tb->size, TString *);  tb->size = newsize;  tb->hash = newhash;}static TString *newlstr (lua_State *L, const char *str, size_t l,                                       unsigned int h) {  TString *ts;  stringtable *tb;  if (l+1 > (MAX_SIZET - sizeof(TString))/sizeof(char))    luaM_toobig(L);  ts = cast(TString *, luaM_malloc(L, (l+1)*sizeof(char)+sizeof(TString)));  ts->tsv.len = l;  ts->tsv.hash = h;  ts->tsv.marked = luaC_white(G(L));  ts->tsv.tt = LUA_TSTRING;  ts->tsv.reserved = 0;  memcpy(ts+1, str, l*sizeof(char));  ((char *)(ts+1))[l] = '\0';  /* ending 0 */  tb = &G(L)->strt;  h = lmod(h, tb->size);  ts->tsv.next = tb->hash[h];  /* chain new entry */  tb->hash[h] = obj2gco(ts);  tb->nuse++;  if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)    luaS_resize(L, tb->size*2);  /* too crowded */  return ts;}TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {  GCObject *o;  unsigned int h = cast(unsigned int, l);  /* seed */  size_t step = (l>>5)+1;  /* if string is too long, don't hash all its chars */  size_t l1;  for (l1=l; l1>=step; l1-=step)  /* compute hash */    h = h ^ ((h<<5)+(h>>2)+cast(unsigned char, str[l1-1]));  for (o = G(L)->strt.hash[lmod(h, G(L)->strt.size)];       o != NULL;       o = o->gch.next) {    TString *ts = rawgco2ts(o);    if (ts->tsv.len == l && (memcmp(str, getstr(ts), l) == 0)) {      /* string may be dead */      if (isdead(G(L), o)) changewhite(o);      return ts;    }  }  return newlstr(L, str, l, h);  /* not found */}Udata *luaS_newudata (lua_State *L, size_t s, Table *e) {  Udata *u;  if (s > MAX_SIZET - sizeof(Udata))    luaM_toobig(L);  u = cast(Udata *, luaM_malloc(L, s + sizeof(Udata)));  u->uv.marked = luaC_white(G(L));  /* is not finalized */  u->uv.tt = LUA_TUSERDATA;  u->uv.len = s;  u->uv.metatable = NULL;  u->uv.env = e;  /* chain it on udata list (after main thread) */  u->uv.next = G(L)->mainthread->next;  G(L)->mainthread->next = obj2gco(u);  return u;}