lstring.h File Reference

#include "lgc.h"
#include "lobject.h"
#include "lstate.h"

Go to the source code of this file.

Macros
#define	MEMERRMSG   "not enough memory"
#define	sizelstring(l)   (offsetof(TString, contents) + ((l) + 1) * sizeof(char))
#define	luaS_newliteral(L, s)
#define	isreserved(s)   ((s)->tt == LUA_VSHRSTR && (s)->extra > 0)
#define	eqshrstr(a, b)   check_exp((a)->tt == LUA_VSHRSTR, (a) == (b))

Functions
LUAI_FUNC unsigned int	luaS_hash (const char *str, size_t l, unsigned int seed)
LUAI_FUNC unsigned int	luaS_hashlongstr (TString *ts)
LUAI_FUNC int	luaS_eqlngstr (TString *a, TString *b)
LUAI_FUNC void	luaS_resize (lua_State *L, int newsize)
LUAI_FUNC void	luaS_clearcache (global_State *g)
LUAI_FUNC void	luaS_init (lua_State *L)
LUAI_FUNC void	luaS_remove (lua_State *L, TString *ts)
LUAI_FUNC Udata *	luaS_newudata (lua_State *L, size_t s, int nuvalue)
LUAI_FUNC TString *	luaS_newlstr (lua_State *L, const char *str, size_t l)
LUAI_FUNC TString *	luaS_new (lua_State *L, const char *str)
LUAI_FUNC TString *	luaS_createlngstrobj (lua_State *L, size_t l)

Macro Definition Documentation

eqshrstr

#define eqshrstr	(		a,
			b )   check_exp((a)->tt == LUA_VSHRSTR, (a) == (b))

Definition at line 41 of file lua-5.4.3/src/lstring.h.

isreserved

#define isreserved

(

s

)

((s)->tt == LUA_VSHRSTR && (s)->extra > 0)

Definition at line 35 of file lua-5.4.3/src/lstring.h.

luaS_newliteral

#define luaS_newliteral	(		L,
			s )

Value:

                                 (luaS_newlstr(L, "" s, \
                                 (sizeof(s)/sizeof(char))-1))

Definition at line 28 of file lua-5.4.3/src/lstring.h.

#define luaS_newliteral(L, s)   (luaS_newlstr(L, "" s, \
                                 (sizeof(s)/sizeof(char))-1))

MEMERRMSG

#define MEMERRMSG   "not enough memory"

Definition at line 19 of file lua-5.4.3/src/lstring.h.

sizelstring

#define sizelstring

(

l

)

(offsetof(TString, contents) + ((l) + 1) * sizeof(char))

Definition at line 26 of file lua-5.4.3/src/lstring.h.

Function Documentation

luaS_clearcache()

LUAI_FUNC void luaS_clearcache

(

global_State *

g

)

Definition at line 103 of file lua-5.3.6/src/lstring.c.

                                       {
  int i, j;
  for (i = 0; i < STRCACHE_N; i++)
    for (j = 0; j < STRCACHE_M; j++) {
    if (iswhite(g->strcache[i][j]))  /* will entry be collected? */
      g->strcache[i][j] = g->memerrmsg;  /* replace it with something fixed */
    }
}

References iswhite, global_State::memerrmsg, global_State::strcache, STRCACHE_M, and STRCACHE_N.

Referenced by atomic(), and atomic().

luaS_createlngstrobj()

LUAI_FUNC TString * luaS_createlngstrobj	(	lua_State *	L,
		size_t	l )

Definition at line 147 of file lua-5.3.6/src/lstring.c.

                                                       {
  TString *ts = createstrobj(L, l, LUA_TLNGSTR, G(L)->seed);
  ts->u.lnglen = l;
  return ts;
}

References createstrobj(), createstrobj(), G, TString::lnglen, LUA_TLNGSTR, LUA_VLNGSTR, and TString::u.

Referenced by LoadString(), loadStringN(), luaS_newlstr(), and luaV_concat().

luaS_eqlngstr()

LUAI_FUNC int luaS_eqlngstr	(	TString *	a,
		TString *	b )

Definition at line 33 of file lua-5.2.4/src/lstring.c.

                                           {
  size_t len = a->tsv.len;
  lua_assert(a->tsv.tt == LUA_TLNGSTR && b->tsv.tt == LUA_TLNGSTR);
  return (a == b) ||  /* same instance or... */
    ((len == b->tsv.len) &&  /* equal length and ... */
     (memcmp(getstr(a), getstr(b), len) == 0));  /* equal contents */
}

References getstr, TString::len, TString::lnglen, lua_assert, LUA_TLNGSTR, LUA_VLNGSTR, TString::tsv, and TString::u.

Referenced by equalkey(), luaS_eqstr(), luaV_equalobj(), and luaV_equalobj_().

luaS_hash()

LUAI_FUNC unsigned int luaS_hash	(	const char *	str,
		size_t	l,
		unsigned int	seed )

Definition at line 51 of file lua-5.2.4/src/lstring.c.

                                                                      {
  unsigned int h = seed ^ cast(unsigned int, l);
  size_t l1;
  size_t step = (l >> LUAI_HASHLIMIT) + 1;
  for (l1 = l; l1 >= step; l1 -= step)
    h = h ^ ((h<<5) + (h>>2) + cast_byte(str[l1 - 1]));
  return h;
}

References cast, cast_byte, cast_uint, and LUAI_HASHLIMIT.

Referenced by internshrstr(), internshrstr(), internshrstr(), luai_makeseed(), luaS_hashlongstr(), mainposition(), makeseed(), and makeseed().

luaS_hashlongstr()

LUAI_FUNC unsigned int luaS_hashlongstr

(

TString *

ts

)

Definition at line 58 of file lua-5.3.6/src/lstring.c.

                                            {
  lua_assert(ts->tt == LUA_TLNGSTR);
  if (ts->extra == 0) {  /* no hash? */
    ts->hash = luaS_hash(getstr(ts), ts->u.lnglen, ts->hash);
    ts->extra = 1;  /* now it has its hash */
  }
  return ts->hash;
}

References TString::extra, getstr, TString::hash, TString::lnglen, lua_assert, LUA_TLNGSTR, LUA_VLNGSTR, luaS_hash(), and TString::u.

Referenced by mainposition(), and mainposition().

luaS_init()

LUAI_FUNC void luaS_init

(

lua_State *

L

)

Definition at line 116 of file lua-5.3.6/src/lstring.c.

                              {
  global_State *g = G(L);
  int i, j;
  luaS_resize(L, MINSTRTABSIZE);  /* initial size of string table */
  /* pre-create memory-error message */
  g->memerrmsg = luaS_newliteral(L, MEMERRMSG);
  luaC_fix(L, obj2gco(g->memerrmsg));  /* it should never be collected */
  for (i = 0; i < STRCACHE_N; i++)  /* fill cache with valid strings */
    for (j = 0; j < STRCACHE_M; j++)
      g->strcache[i][j] = g->memerrmsg;
}

References G, stringtable::hash, luaC_fix(), luaM_newvector, luaS_newliteral, luaS_resize(), global_State::memerrmsg, MEMERRMSG, MINSTRTABSIZE, obj2gco, stringtable::size, global_State::strcache, STRCACHE_M, STRCACHE_N, and tablerehash().

Referenced by f_luaopen(), and f_luaopen().

luaS_new()

LUAI_FUNC TString * luaS_new	(	lua_State *	L,
		const char *	str )

Definition at line 170 of file lua-5.2.4/src/lstring.c.

                                                  {
  return luaS_newlstr(L, str, strlen(str));
}

References G, getstr, luaS_newlstr(), point2uint, STRCACHE_M, and STRCACHE_N.

luaS_newlstr()

LUAI_FUNC 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, createstrobj(), G, GCObject::gch, getstr, internshrstr(), internshrstr(), internshrstr(), isdead, TString::len, lmod, LUA_TLNGSTR, LUAI_MAXSHORTLEN, luaM_toobig(), luaS_createlngstrobj(), MAX_SIZE, MAX_SIZET, newlstr(), NULL, rawgco2ts, and TString::tsv.

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

luaS_newudata()

LUAI_FUNC Udata * luaS_newudata	(	lua_State *	L,
		size_t	s,
		int	nuvalue )

Definition at line 258 of file lua-5.4.3/src/lstring.c.

                                                           {
  Udata *u;
  int i;
  GCObject *o;
  if (l_unlikely(s > MAX_SIZE - udatamemoffset(nuvalue)))
    luaM_toobig(L);
  o = luaC_newobj(L, LUA_VUSERDATA, sizeudata(nuvalue, s));
  u = gco2u(o);
  u->len = s;
  u->nuvalue = nuvalue;
  u->metatable = NULL;
  for (i = 0; i < nuvalue; i++)
    setnilvalue(&u->uv[i].uv);
  return u;
}

References gco2u, Udata::len, LUA_VUSERDATA, luaC_newobj(), luaM_toobig(), MAX_SIZE, Udata::metatable, NULL, Udata::nuvalue, s, setnilvalue, sizeudata, udatamemoffset, and Udata::uv.

luaS_remove()

LUAI_FUNC void luaS_remove	(	lua_State *	L,
		TString *	ts )

Definition at line 154 of file lua-5.3.6/src/lstring.c.

                                             {
  stringtable *tb = &G(L)->strt;
  TString **p = &tb->hash[lmod(ts->hash, tb->size)];
  while (*p != ts)  /* find previous element */
    p = &(*p)->u.hnext;
  *p = (*p)->u.hnext;  /* remove element from its list */
  tb->nuse--;
}

References G, TString::hash, stringtable::hash, TString::hnext, lmod, stringtable::nuse, stringtable::size, and TString::u.

Referenced by freeobj(), and freeobj().

luaS_resize()

LUAI_FUNC 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 bitmask, cast_int, G, GCObject::gch, gch, gco2ts, GCSsweepstring, TString::hash, stringtable::hash, TString::hnext, lmod, lua_assert, luaC_runtilstate(), luaM_freearray, luaM_newvector, luaM_reallocvector, next, NULL, resetoldbit, stringtable::size, tablerehash(), and TString::u.

Referenced by checkSizes(), checkSizes(), checkSizes(), checkSizes(), f_luaopen(), f_luaopen(), growstrtab(), internshrstr(), luaS_init(), newlstr(), and newshrstr().