ltable.c-Dateireferenz

#include <math.h>
#include <string.h>
#include "lua.h"
#include "ldebug.h"
#include "ldo.h"
#include "lgc.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
#include "ltable.h"

Include-Abhängigkeitsdiagramm für ltable.c:

gehe zum Quellcode dieser Datei

Makrodefinitionen
#define	ltable_c
#define	LUA_CORE
#define	MAXBITS   (LUAI_BITSINT-2)
#define	MAXASIZE   (1 << MAXBITS)
#define	hashpow2(t, n)   (gnode(t, lmod((n), sizenode(t))))
#define	hashstr(t, str)   hashpow2(t, (str)->tsv.hash)
#define	hashboolean(t, p)   hashpow2(t, p)
#define	hashmod(t, n)   (gnode(t, ((n) % ((sizenode(t)-1)|1))))
#define	hashpointer(t, p)   hashmod(t, IntPoint(p))
#define	numints   cast_int(sizeof(lua_Number)/sizeof(int))
#define	dummynode   (&dummynode_)

Funktionen
static Node *	hashnum (const Table *t, lua_Number n)
static Node *	mainposition (const Table *t, const TValue *key)
static int	arrayindex (const TValue *key)
static int	findindex (lua_State *L, Table *t, StkId key)
LUAI_FUNC int	luaH_next (lua_State *L, Table *t, StkId key)
static int	computesizes (int nums[], int *narray)
static int	countint (const TValue *key, int *nums)
static int	numusearray (const Table *t, int *nums)
static int	numusehash (const Table *t, int *nums, int *pnasize)
static void	setarrayvector (lua_State *L, Table *t, int size)
static void	setnodevector (lua_State *L, Table *t, int size)
static void	resize (lua_State *L, Table *t, int nasize, int nhsize)
LUAI_FUNC void	luaH_resizearray (lua_State *L, Table *t, int nasize)
static void	rehash (lua_State *L, Table *t, const TValue *ek)
LUAI_FUNC Table *	luaH_new (lua_State *L, int narray, int nhash)
LUAI_FUNC void	luaH_free (lua_State *L, Table *t)
static Node *	getfreepos (Table *t)
static TValue *	newkey (lua_State *L, Table *t, const TValue *key)
LUAI_FUNC const TValue *	luaH_getnum (Table *t, int key)
LUAI_FUNC const TValue *	luaH_getstr (Table *t, TString *key)
LUAI_FUNC const TValue *	luaH_get (Table *t, const TValue *key)
LUAI_FUNC TValue *	luaH_set (lua_State *L, Table *t, const TValue *key)
LUAI_FUNC TValue *	luaH_setnum (lua_State *L, Table *t, int key)
LUAI_FUNC TValue *	luaH_setstr (lua_State *L, Table *t, TString *key)
static int	unbound_search (Table *t, unsigned int j)
LUAI_FUNC int	luaH_getn (Table *t)

Variablen
static const Node	dummynode_

Makro-Dokumentation

#define dummynode   (&dummynode_)

Definiert in Zeile 73 der Datei ltable.c.

#define hashboolean	(		t,
			p
	)		hashpow2(t, p)

Definiert in Zeile 53 der Datei ltable.c.

#define hashmod	(		t,
			n
	)		(gnode(t, ((n) % ((sizenode(t)-1)|1))))

Definiert in Zeile 60 der Datei ltable.c.

#define hashpointer	(		t,
			p
	)		hashmod(t, IntPoint(p))

Definiert in Zeile 63 der Datei ltable.c.

#define hashpow2	(		t,
			n
	)		(gnode(t, lmod((n), sizenode(t))))

Definiert in Zeile 50 der Datei ltable.c.

#define hashstr	(		t,
			str
	)		hashpow2(t, (str)->tsv.hash)

Definiert in Zeile 52 der Datei ltable.c.

#define ltable_c

Definiert in Zeile 24 der Datei ltable.c.

#define LUA_CORE

Definiert in Zeile 25 der Datei ltable.c.

#define MAXASIZE   (1 << MAXBITS)

Definiert in Zeile 47 der Datei ltable.c.

#define MAXBITS   (LUAI_BITSINT-2)

Definiert in Zeile 44 der Datei ltable.c.

#define numints   cast_int(sizeof(lua_Number)/sizeof(int))

Definiert in Zeile 69 der Datei ltable.c.

Dokumentation der Funktionen

static int arrayindex ( const TValue *  key)

static

Definiert in Zeile 120 der Datei ltable.c.

                                          {
  if (ttisnumber(key)) {
    lua_Number n = nvalue(key);
    int k;
    lua_number2int(k, n);
    if (luai_numeq(cast_num(k), n))
      return k;
  }
  return -1;  /* `key' did not match some condition */
}

static int computesizes ( int  nums[], int *  narray  )

static

Definiert in Zeile 189 der Datei ltable.c.

                                                  {
  int i;
  int twotoi;  /* 2^i */
  int a = 0;  /* number of elements smaller than 2^i */
  int na = 0;  /* number of elements to go to array part */
  int n = 0;  /* optimal size for array part */
  for (i = 0, twotoi = 1; twotoi/2 < *narray; i++, twotoi *= 2) {
    if (nums[i] > 0) {
      a += nums[i];
      if (a > twotoi/2) {  /* more than half elements present? */
        n = twotoi;  /* optimal size (till now) */
        na = a;  /* all elements smaller than n will go to array part */
      }
    }
    if (a == *narray) break;  /* all elements already counted */
  }
  *narray = n;
  lua_assert(*narray/2 <= na && na <= *narray);
  return na;
}

static int countint ( const TValue *  key, int *  nums  )

static

Definiert in Zeile 211 der Datei ltable.c.

                                                   {
  int k = arrayindex(key);
  if (0 < k && k <= MAXASIZE) {  /* is `key' an appropriate array index? */
    nums[ceillog2(k)]++;  /* count as such */
    return 1;
  }
  else
    return 0;
}

static int findindex ( lua_State *  L, Table *  t, StkId  key  )

static

Definiert in Zeile 137 der Datei ltable.c.

                                                         {
  int i;
  if (ttisnil(key)) return -1;  /* first iteration */
  i = arrayindex(key);
  if (0 < i && i <= t->sizearray)  /* is `key' inside array part? */
    return i-1;  /* yes; that's the index (corrected to C) */
  else {
    Node *n = mainposition(t, key);
    do {  /* check whether `key' is somewhere in the chain */
      /* key may be dead already, but it is ok to use it in `next' */
      if (luaO_rawequalObj(key2tval(n), key) ||
            (ttype(gkey(n)) == LUA_TDEADKEY && iscollectable(key) &&
             gcvalue(gkey(n)) == gcvalue(key))) {
        i = cast_int(n - gnode(t, 0));  /* key index in hash table */
        /* hash elements are numbered after array ones */
        return i + t->sizearray;
      }
      else n = gnext(n);
    } while (n);
    luaG_runerror(L, "invalid key to " LUA_QL("next"));  /* key not found */
    return 0;  /* to avoid warnings */
  }
}

static Node* getfreepos ( Table *  t)

static

Definiert in Zeile 382 der Datei ltable.c.

                                   {
  while (t->lastfree-- > t->node) {
    if (ttisnil(gkey(t->lastfree)))
      return t->lastfree;
  }
  return NULL;  /* could not find a free place */
}

static Node* hashnum ( const Table *  t, lua_Number  n  )

static

Definiert in Zeile 84 der Datei ltable.c.

                                                    {
  unsigned int a[numints];
  int i;
  if (luai_numeq(n, 0))  /* avoid problems with -0 */
    return gnode(t, 0);
  memcpy(a, &n, sizeof(a));
  for (i = 1; i < numints; i++) a[0] += a[i];
  return hashmod(t, a[0]);
}

LUAI_FUNC void luaH_free	(	lua_State *	L,
		Table *	t
	)

Definiert in Zeile 374 der Datei ltable.c.

                                                  {
  if (t->node != dummynode)
    luaM_freearray(L, t->node, sizenode(t), Node);
  luaM_freearray(L, t->array, t->sizearray, TValue);
  luaM_free(L, t);
}

LUAI_FUNC const TValue* luaH_get	(	Table *	t,
		const TValue *	key
	)

Definiert in Zeile 469 der Datei ltable.c.

                                                               {
  switch (ttype(key)) {
    case LUA_TNIL: return luaO_nilobject;
    case LUA_TSTRING: return luaH_getstr(t, rawtsvalue(key));
    case LUA_TNUMBER: {
      int k;
      lua_Number n = nvalue(key);
      lua_number2int(k, n);
      if (luai_numeq(cast_num(k), nvalue(key))) /* index is int? */
        return luaH_getnum(t, k);  /* use specialized version */
      /* else go through */
    }
    default: {
      Node *n = mainposition(t, key);
      do {  /* check whether `key' is somewhere in the chain */
        if (luaO_rawequalObj(key2tval(n), key))
          return gval(n);  /* that's it */
        else n = gnext(n);
      } while (n);
      return luaO_nilobject;
    }
  }
}

LUAI_FUNC int luaH_getn

(

Table *

t)

Definiert in Zeile 560 der Datei ltable.c.

                                   {
  unsigned int j = t->sizearray;
  if (j > 0 && ttisnil(&t->array[j - 1])) {
    /* there is a boundary in the array part: (binary) search for it */
    unsigned int i = 0;
    while (j - i > 1) {
      unsigned int m = (i+j)/2;
      if (ttisnil(&t->array[m - 1])) j = m;
      else i = m;
    }
    return i;
  }
  /* else must find a boundary in hash part */
  else if (t->node == dummynode)  /* hash part is empty? */
    return j;  /* that is easy... */
  else return unbound_search(t, j);
}

LUAI_FUNC const TValue* luaH_getnum	(	Table *	t,
		int	key
	)

Definiert in Zeile 435 der Datei ltable.c.

                                                        {
  /* (1 <= key && key <= t->sizearray) */
  if (cast(unsigned int, key-1) < cast(unsigned int, t->sizearray))
    return &t->array[key-1];
  else {
    lua_Number nk = cast_num(key);
    Node *n = hashnum(t, nk);
    do {  /* check whether `key' is somewhere in the chain */
      if (ttisnumber(gkey(n)) && luai_numeq(nvalue(gkey(n)), nk))
        return gval(n);  /* that's it */
      else n = gnext(n);
    } while (n);
    return luaO_nilobject;
  }
}

LUAI_FUNC const TValue* luaH_getstr	(	Table *	t,
		TString *	key
	)

Definiert in Zeile 455 der Datei ltable.c.

                                                             {
  Node *n = hashstr(t, key);
  do {  /* check whether `key' is somewhere in the chain */
    if (ttisstring(gkey(n)) && rawtsvalue(gkey(n)) == key)
      return gval(n);  /* that's it */
    else n = gnext(n);
  } while (n);
  return luaO_nilobject;
}

LUAI_FUNC Table* luaH_new	(	lua_State *	L,
		int	narray,
		int	nhash
	)

Definiert in Zeile 358 der Datei ltable.c.

                                                                {
  Table *t = luaM_new(L, Table);
  luaC_link(L, obj2gco(t), LUA_TTABLE);
  t->metatable = NULL;
  t->flags = cast_byte(~0);
  /* temporary values (kept only if some malloc fails) */
  t->array = NULL;
  t->sizearray = 0;
  t->lsizenode = 0;
  t->node = cast(Node *, dummynode);
  setarrayvector(L, t, narray);
  setnodevector(L, t, nhash);
  return t;
}

LUAI_FUNC int luaH_next	(	lua_State *	L,
		Table *	t,
		StkId	key
	)

Definiert in Zeile 162 der Datei ltable.c.

                                                            {
  int i = findindex(L, t, key);  /* find original element */
  for (i++; i < t->sizearray; i++) {  /* try first array part */
    if (!ttisnil(&t->array[i])) {  /* a non-nil value? */
      setnvalue(key, cast_num(i+1));
      setobj2s(L, key+1, &t->array[i]);
      return 1;
    }
  }
  for (i -= t->sizearray; i < sizenode(t); i++) {  /* then hash part */
    if (!ttisnil(gval(gnode(t, i)))) {  /* a non-nil value? */
      setobj2s(L, key, key2tval(gnode(t, i)));
      setobj2s(L, key+1, gval(gnode(t, i)));
      return 1;
    }
  }
  return 0;  /* no more elements */
}

LUAI_FUNC void luaH_resizearray	(	lua_State *	L,
		Table *	t,
		int	nasize
	)

Definiert in Zeile 327 der Datei ltable.c.

                                                                     {
  int nsize = (t->node == dummynode) ? 0 : sizenode(t);
  resize(L, t, nasize, nsize);
}

LUAI_FUNC TValue* luaH_set	(	lua_State *	L,
		Table *	t,
		const TValue *	key
	)

Definiert in Zeile 494 der Datei ltable.c.

                                                                       {
  const TValue *p = luaH_get(t, key);
  t->flags = 0;
  if (p != luaO_nilobject)
    return cast(TValue *, p);
  else {
    if (ttisnil(key)) luaG_runerror(L, "table index is nil");
    else if (ttisnumber(key) && luai_numisnan(nvalue(key)))
      luaG_runerror(L, "table index is NaN");
    return newkey(L, t, key);
  }
}

LUAI_FUNC TValue* luaH_setnum	(	lua_State *	L,
		Table *	t,
		int	key
	)

Definiert in Zeile 508 der Datei ltable.c.

                                                                {
  const TValue *p = luaH_getnum(t, key);
  if (p != luaO_nilobject)
    return cast(TValue *, p);
  else {
    TValue k;
    setnvalue(&k, cast_num(key));
    return newkey(L, t, &k);
  }
}

LUAI_FUNC TValue* luaH_setstr	(	lua_State *	L,
		Table *	t,
		TString *	key
	)

Definiert in Zeile 520 der Datei ltable.c.

                                                                     {
  const TValue *p = luaH_getstr(t, key);
  if (p != luaO_nilobject)
    return cast(TValue *, p);
  else {
    TValue k;
    setsvalue(L, &k, key);
    return newkey(L, t, &k);
  }
}

static Node* mainposition ( const Table *  t, const TValue *  key  )

static

Definiert in Zeile 100 der Datei ltable.c.

                                                              {
  switch (ttype(key)) {
    case LUA_TNUMBER:
      return hashnum(t, nvalue(key));
    case LUA_TSTRING:
      return hashstr(t, rawtsvalue(key));
    case LUA_TBOOLEAN:
      return hashboolean(t, bvalue(key));
    case LUA_TLIGHTUSERDATA:
      return hashpointer(t, pvalue(key));
    default:
      return hashpointer(t, gcvalue(key));
  }
}

static TValue* newkey ( lua_State *  L, Table *  t, const TValue *  key  )

static

Definiert in Zeile 399 der Datei ltable.c.

                                                                  {
  Node *mp = mainposition(t, key);
  if (!ttisnil(gval(mp)) || mp == dummynode) {
    Node *othern;
    Node *n = getfreepos(t);  /* get a free place */
    if (n == NULL) {  /* cannot find a free place? */
      rehash(L, t, key);  /* grow table */
      return luaH_set(L, t, key);  /* re-insert key into grown table */
    }
    lua_assert(n != dummynode);
    othern = mainposition(t, key2tval(mp));
    if (othern != mp) {  /* is colliding node out of its main position? */
      /* yes; move colliding node into free position */
      while (gnext(othern) != mp) othern = gnext(othern);  /* find previous */
      gnext(othern) = n;  /* redo the chain with `n' in place of `mp' */
      *n = *mp;  /* copy colliding node into free pos. (mp->next also goes) */
      gnext(mp) = NULL;  /* now `mp' is free */
      setnilvalue(gval(mp));
    }
    else {  /* colliding node is in its own main position */
      /* new node will go into free position */
      gnext(n) = gnext(mp);  /* chain new position */
      gnext(mp) = n;
      mp = n;
    }
  }
  gkey(mp)->value = key->value; gkey(mp)->tt = key->tt;
  luaC_barriert(L, t, key);
  lua_assert(ttisnil(gval(mp)));
  return gval(mp);
}

static int numusearray ( const Table *  t, int *  nums  )

static

Definiert in Zeile 222 der Datei ltable.c.

                                                   {
  int lg;
  int ttlg;  /* 2^lg */
  int ause = 0;  /* summation of `nums' */
  int i = 1;  /* count to traverse all array keys */
  for (lg=0, ttlg=1; lg<=MAXBITS; lg++, ttlg*=2) {  /* for each slice */
    int lc = 0;  /* counter */
    int lim = ttlg;
    if (lim > t->sizearray) {
      lim = t->sizearray;  /* adjust upper limit */
      if (i > lim)
        break;  /* no more elements to count */
    }
    /* count elements in range (2^(lg-1), 2^lg] */
    for (; i <= lim; i++) {
      if (!ttisnil(&t->array[i-1]))
        lc++;
    }
    nums[lg] += lc;
    ause += lc;
  }
  return ause;
}

static int numusehash ( const Table *  t, int *  nums, int *  pnasize  )

static

Definiert in Zeile 247 der Datei ltable.c.

                                                                {
  int totaluse = 0;  /* total number of elements */
  int ause = 0;  /* summation of `nums' */
  int i = sizenode(t);
  while (i--) {
    Node *n = &t->node[i];
    if (!ttisnil(gval(n))) {
      ause += countint(key2tval(n), nums);
      totaluse++;
    }
  }
  *pnasize += ause;
  return totaluse;
}

static void rehash ( lua_State *  L, Table *  t, const TValue *  ek  )

static

Definiert in Zeile 333 der Datei ltable.c.

                                                              {
  int nasize, na;
  int nums[MAXBITS+1];  /* nums[i] = number of keys between 2^(i-1) and 2^i */
  int i;
  int totaluse;
  for (i=0; i<=MAXBITS; i++) nums[i] = 0;  /* reset counts */
  nasize = numusearray(t, nums);  /* count keys in array part */
  totaluse = nasize;  /* all those keys are integer keys */
  totaluse += numusehash(t, nums, &nasize);  /* count keys in hash part */
  /* count extra key */
  nasize += countint(ek, nums);
  totaluse++;
  /* compute new size for array part */
  na = computesizes(nums, &nasize);
  /* resize the table to new computed sizes */
  resize(L, t, nasize, totaluse - na);
}

static void resize ( lua_State *  L, Table *  t, int  nasize, int  nhsize  )

static

Definiert in Zeile 297 der Datei ltable.c.

                                                                    {
  int i;
  int oldasize = t->sizearray;
  int oldhsize = t->lsizenode;
  Node *nold = t->node;  /* save old hash ... */
  if (nasize > oldasize)  /* array part must grow? */
    setarrayvector(L, t, nasize);
  /* create new hash part with appropriate size */
  setnodevector(L, t, nhsize);  
  if (nasize < oldasize) {  /* array part must shrink? */
    t->sizearray = nasize;
    /* re-insert elements from vanishing slice */
    for (i=nasize; i<oldasize; i++) {
      if (!ttisnil(&t->array[i]))
        setobjt2t(L, luaH_setnum(L, t, i+1), &t->array[i]);
    }
    /* shrink array */
    luaM_reallocvector(L, t->array, oldasize, nasize, TValue);
  }
  /* re-insert elements from hash part */
  for (i = twoto(oldhsize) - 1; i >= 0; i--) {
    Node *old = nold+i;
    if (!ttisnil(gval(old)))
      setobjt2t(L, luaH_set(L, t, key2tval(old)), gval(old));
  }
  if (nold != dummynode)
    luaM_freearray(L, nold, twoto(oldhsize), Node);  /* free old array */
}

static void setarrayvector ( lua_State *  L, Table *  t, int  size  )

static

Definiert in Zeile 263 der Datei ltable.c.

                                                              {
  int i;
  luaM_reallocvector(L, t->array, t->sizearray, size, TValue);
  for (i=t->sizearray; i<size; i++)
     setnilvalue(&t->array[i]);
  t->sizearray = size;
}

static void setnodevector ( lua_State *  L, Table *  t, int  size  )

static

Definiert in Zeile 272 der Datei ltable.c.

                                                             {
  int lsize;
  if (size == 0) {  /* no elements to hash part? */
    t->node = cast(Node *, dummynode);  /* use common `dummynode' */
    lsize = 0;
  }
  else {
    int i;
    lsize = ceillog2(size);
    if (lsize > MAXBITS)
      luaG_runerror(L, "table overflow");
    size = twoto(lsize);
    t->node = luaM_newvector(L, size, Node);
    for (i=0; i<size; i++) {
      Node *n = gnode(t, i);
      gnext(n) = NULL;
      setnilvalue(gkey(n));
      setnilvalue(gval(n));
    }
  }
  t->lsizenode = cast_byte(lsize);
  t->lastfree = gnode(t, size);  /* all positions are free */
}

static int unbound_search ( Table *  t, unsigned int  j  )

static

Definiert in Zeile 532 der Datei ltable.c.

                                                     {
  unsigned int i = j;  /* i is zero or a present index */
  j++;
  /* find `i' and `j' such that i is present and j is not */
  while (!ttisnil(luaH_getnum(t, j))) {
    i = j;
    j *= 2;
    if (j > cast(unsigned int, MAX_INT)) {  /* overflow? */
      /* table was built with bad purposes: resort to linear search */
      i = 1;
      while (!ttisnil(luaH_getnum(t, i))) i++;
      return i - 1;
    }
  }
  /* now do a binary search between them */
  while (j - i > 1) {
    unsigned int m = (i+j)/2;
    if (ttisnil(luaH_getnum(t, m))) j = m;
    else i = m;
  }
  return i;
}

Variablen-Dokumentation

const Node dummynode_

static

Initialisierung:

= {
  {{NULL}, LUA_TNIL},  
  {{{NULL}, LUA_TNIL, NULL}}  
}

Definiert in Zeile 75 der Datei ltable.c.