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-rw-r--r--source3/lua-5.1.4/src/ltable.c588
1 files changed, 0 insertions, 588 deletions
diff --git a/source3/lua-5.1.4/src/ltable.c b/source3/lua-5.1.4/src/ltable.c
deleted file mode 100644
index 677b0e95c6..0000000000
--- a/source3/lua-5.1.4/src/ltable.c
+++ /dev/null
@@ -1,588 +0,0 @@
-/*
-** $Id: ltable.c,v 2.32.1.2 2007/12/28 15:32:23 roberto Exp $
-** Lua tables (hash)
-** See Copyright Notice in lua.h
-*/
-
-
-/*
-** Implementation of tables (aka arrays, objects, or hash tables).
-** Tables keep its elements in two parts: an array part and a hash part.
-** Non-negative integer keys are all candidates to be kept in the array
-** part. The actual size of the array is the largest `n' such that at
-** least half the slots between 0 and n are in use.
-** Hash uses a mix of chained scatter table with Brent's variation.
-** A main invariant of these tables is that, if an element is not
-** in its main position (i.e. the `original' position that its hash gives
-** to it), then the colliding element is in its own main position.
-** Hence even when the load factor reaches 100%, performance remains good.
-*/
-
-#include <math.h>
-#include <string.h>
-
-#define ltable_c
-#define LUA_CORE
-
-#include "lua.h"
-
-#include "ldebug.h"
-#include "ldo.h"
-#include "lgc.h"
-#include "lmem.h"
-#include "lobject.h"
-#include "lstate.h"
-#include "ltable.h"
-
-
-/*
-** max size of array part is 2^MAXBITS
-*/
-#if LUAI_BITSINT > 26
-#define MAXBITS 26
-#else
-#define MAXBITS (LUAI_BITSINT-2)
-#endif
-
-#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)
-
-
-/*
-** for some types, it is better to avoid modulus by power of 2, as
-** they tend to have many 2 factors.
-*/
-#define hashmod(t,n) (gnode(t, ((n) % ((sizenode(t)-1)|1))))
-
-
-#define hashpointer(t,p) hashmod(t, IntPoint(p))
-
-
-/*
-** number of ints inside a lua_Number
-*/
-#define numints cast_int(sizeof(lua_Number)/sizeof(int))
-
-
-
-#define dummynode (&dummynode_)
-
-static const Node dummynode_ = {
- {{NULL}, LUA_TNIL}, /* value */
- {{{NULL}, LUA_TNIL, NULL}} /* key */
-};
-
-
-/*
-** hash for lua_Numbers
-*/
-static Node *hashnum (const Table *t, lua_Number n) {
- 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]);
-}
-
-
-
-/*
-** returns the `main' position of an element in a table (that is, the index
-** of its hash value)
-*/
-static Node *mainposition (const Table *t, const TValue *key) {
- 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));
- }
-}
-
-
-/*
-** returns the index for `key' if `key' is an appropriate key to live in
-** the array part of the table, -1 otherwise.
-*/
-static int arrayindex (const TValue *key) {
- 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 */
-}
-
-
-/*
-** returns the index of a `key' for table traversals. First goes all
-** elements in the array part, then elements in the hash part. The
-** beginning of a traversal is signalled by -1.
-*/
-static int findindex (lua_State *L, Table *t, StkId key) {
- 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 */
- }
-}
-
-
-int luaH_next (lua_State *L, Table *t, StkId key) {
- 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 */
-}
-
-
-/*
-** {=============================================================
-** Rehash
-** ==============================================================
-*/
-
-
-static int computesizes (int nums[], int *narray) {
- 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) {
- 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 numusearray (const Table *t, int *nums) {
- 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) {
- 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 setarrayvector (lua_State *L, Table *t, int size) {
- 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) {
- 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 void resize (lua_State *L, Table *t, int nasize, int nhsize) {
- 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 */
-}
-
-
-void luaH_resizearray (lua_State *L, Table *t, int nasize) {
- int nsize = (t->node == dummynode) ? 0 : sizenode(t);
- resize(L, t, nasize, nsize);
-}
-
-
-static void rehash (lua_State *L, Table *t, const TValue *ek) {
- 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);
-}
-
-
-
-/*
-** }=============================================================
-*/
-
-
-Table *luaH_new (lua_State *L, int narray, int nhash) {
- 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;
-}
-
-
-void luaH_free (lua_State *L, Table *t) {
- if (t->node != dummynode)
- luaM_freearray(L, t->node, sizenode(t), Node);
- luaM_freearray(L, t->array, t->sizearray, TValue);
- luaM_free(L, t);
-}
-
-
-static Node *getfreepos (Table *t) {
- while (t->lastfree-- > t->node) {
- if (ttisnil(gkey(t->lastfree)))
- return t->lastfree;
- }
- return NULL; /* could not find a free place */
-}
-
-
-
-/*
-** inserts a new key into a hash table; first, check whether key's main
-** position is free. If not, check whether colliding node is in its main
-** position or not: if it is not, move colliding node to an empty place and
-** put new key in its main position; otherwise (colliding node is in its main
-** position), new key goes to an empty position.
-*/
-static TValue *newkey (lua_State *L, Table *t, const TValue *key) {
- 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);
-}
-
-
-/*
-** search function for integers
-*/
-const TValue *luaH_getnum (Table *t, int key) {
- /* (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;
- }
-}
-
-
-/*
-** search function for strings
-*/
-const TValue *luaH_getstr (Table *t, TString *key) {
- 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;
-}
-
-
-/*
-** main search function
-*/
-const TValue *luaH_get (Table *t, const TValue *key) {
- 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;
- }
- }
-}
-
-
-TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
- 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);
- }
-}
-
-
-TValue *luaH_setnum (lua_State *L, Table *t, int key) {
- 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);
- }
-}
-
-
-TValue *luaH_setstr (lua_State *L, Table *t, TString *key) {
- 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 int unbound_search (Table *t, unsigned int j) {
- 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;
-}
-
-
-/*
-** Try to find a boundary in table `t'. A `boundary' is an integer index
-** such that t[i] is non-nil and t[i+1] is nil (and 0 if t[1] is nil).
-*/
-int luaH_getn (Table *t) {
- 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);
-}
-
-
-
-#if defined(LUA_DEBUG)
-
-Node *luaH_mainposition (const Table *t, const TValue *key) {
- return mainposition(t, key);
-}
-
-int luaH_isdummy (Node *n) { return n == dummynode; }
-
-#endif
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