lstring.c File Reference

#include <string.h>
#include "lua.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
#include "lstring.h"

Go to the source code of this file.

Macros
#define	lstring_c
#define	LUA_CORE

Functions
void	luaS_resize (lua_State *L, int newsize)
static TString *	newlstr (lua_State *L, const char *str, size_t l, unsigned int h)
TString *	luaS_newlstr (lua_State *L, const char *str, size_t l)
Udata *	luaS_newudata (lua_State *L, size_t s, Table *e)

Macro Definition Documentation

lstring_c

#define lstring_c

Definition at line 10 of file lua-5.1.5/src/lstring.c.

LUA_CORE

#define LUA_CORE

Definition at line 11 of file lua-5.1.5/src/lstring.c.

Function Documentation

luaS_newlstr()

TString * luaS_newlstr	(	lua_State *	L,
		const char *	str,
		size_t	l )

Definition at line 75 of file lua-5.1.5/src/lstring.c.

                                                                {
  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 */
}

References cast, changewhite, G, GCObject::gch, getstr, isdead, TString::len, lmod, newlstr(), NULL, rawgco2ts, and TString::tsv.

Referenced by LoadString(), LoadString(), LoadString(), loadStringN(), lua_concat(), lua_pushlstring(), luaK_numberK(), luaO_pushvfstring(), luaO_tostring(), luaO_tostring(), luaV_concat(), luaV_concat(), luaV_tostring(), luaX_newstring(), pushstr(), pushstr(), and pushstr().

luaS_newudata()

Udata * luaS_newudata	(	lua_State *	L,
		size_t	s,
		Table *	e )

Definition at line 96 of file lua-5.1.5/src/lstring.c.

                                                        {
  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;
}

References cast, Udata::env, G, Udata::len, LUA_TUSERDATA, luaC_white, luaM_malloc, luaM_toobig(), MAX_SIZET, Udata::metatable, NULL, obj2gco, s, and Udata::uv.

Referenced by lua_newuserdata(), and lua_newuserdatauv().

luaS_resize()

void luaS_resize	(	lua_State *	L,
		int	newsize )

Definition at line 22 of file lua-5.1.5/src/lstring.c.

                                             {
  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;
}

References cast_int, G, GCObject::gch, gco2ts, GCSsweepstring, stringtable::hash, lmod, lua_assert, luaM_freearray, luaM_newvector, next, NULL, and stringtable::size.

Referenced by checkSizes(), checkSizes(), checkSizes(), checkSizes(), f_luaopen(), f_luaopen(), and newlstr().

newlstr()

static TString * newlstr ( lua_State * L, const char * str, size_t l, unsigned int h )

static

Definition at line 50 of file lua-5.1.5/src/lstring.c.

                                                       {
  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;
}

References cast, G, TString::hash, stringtable::hash, TString::len, lmod, LUA_TSTRING, luaC_white, luaM_malloc, luaM_toobig(), luaS_resize(), MAX_INT, MAX_SIZET, stringtable::nuse, obj2gco, TString::reserved, stringtable::size, and TString::tsv.

Referenced by luaS_newlstr().