Diff: squirrel/sqtable.cpp

Revision:

0:97a4f8cc534c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/squirrel/sqtable.cpp	Tue Dec 16 10:20:34 2014 +0000
@@ -0,0 +1,221 @@
+/*
+see copyright notice in squirrel.h
+*/
+#include "sqpcheader.h"
+#include "sqvm.h"
+#include "sqtable.h"
+#include "sqfuncproto.h"
+#include "sqclosure.h"
+
+SQTable::SQTable(SQSharedState *ss,SQInteger nInitialSize)
+{
+	SQInteger pow2size=MINPOWER2;
+	while(nInitialSize>pow2size)pow2size=pow2size<<1;
+	AllocNodes(pow2size);
+	_usednodes = 0;
+	_delegate = NULL;
+	INIT_CHAIN();
+	ADD_TO_CHAIN(&_sharedstate->_gc_chain,this);
+}
+
+void SQTable::Remove(const SQObjectPtr &key)
+{
+	
+	_HashNode *n = _Get(key, HashObj(key) & (_numofnodes - 1));
+	if (n) {
+		n->val.Null();
+		n->key.Null();
+		_usednodes--;
+		Rehash(false);
+	}
+}
+
+void SQTable::AllocNodes(SQInteger nSize)
+{
+	_HashNode *nodes=(_HashNode *)SQ_MALLOC(sizeof(_HashNode)*nSize);
+	for(SQInteger i=0;i<nSize;i++){
+		_HashNode &n = nodes[i];
+		new (&n) _HashNode;
+		n.next=NULL;
+	}
+	_numofnodes=nSize;
+	_nodes=nodes;
+	_firstfree=&_nodes[_numofnodes-1];
+}
+
+void SQTable::Rehash(bool force)
+{
+	SQInteger oldsize=_numofnodes;
+	//prevent problems with the integer division
+	if(oldsize<4)oldsize=4;
+	_HashNode *nold=_nodes;
+	SQInteger nelems=CountUsed();
+	if (nelems >= oldsize-oldsize/4)  /* using more than 3/4? */
+		AllocNodes(oldsize*2);
+	else if (nelems <= oldsize/4 &&  /* less than 1/4? */
+		oldsize > MINPOWER2)
+		AllocNodes(oldsize/2);
+	else if(force)
+		AllocNodes(oldsize);
+	else
+		return;
+	_usednodes = 0;
+	for (SQInteger i=0; i<oldsize; i++) {
+		_HashNode *old = nold+i;
+		if (type(old->key) != OT_NULL)
+			NewSlot(old->key,old->val);
+	}
+	for(SQInteger k=0;k<oldsize;k++) 
+		nold[k].~_HashNode();
+	SQ_FREE(nold,oldsize*sizeof(_HashNode));
+}
+
+SQTable *SQTable::Clone()
+{
+	SQTable *nt=Create(_opt_ss(this),_numofnodes);
+#ifdef _FAST_CLONE
+	_HashNode *basesrc = _nodes;
+	_HashNode *basedst = nt->_nodes;
+	_HashNode *src = _nodes;
+	_HashNode *dst = nt->_nodes;
+	SQInteger n = 0;
+	for(n = 0; n < _numofnodes; n++) {
+		dst->key = src->key;
+		dst->val = src->val;
+		if(src->next) {
+			assert(src->next > basesrc);
+			dst->next = basedst + (src->next - basesrc);
+			assert(dst != dst->next);
+		}
+		dst++;
+		src++;
+	}
+	assert(_firstfree > basesrc);
+	assert(_firstfree != NULL);
+	nt->_firstfree = basedst + (_firstfree - basesrc);
+	nt->_usednodes = _usednodes;
+#else
+	SQInteger ridx=0;
+	SQObjectPtr key,val;
+	while((ridx=Next(true,ridx,key,val))!=-1){
+		nt->NewSlot(key,val);
+	}
+#endif
+	nt->SetDelegate(_delegate);
+	return nt;
+}
+
+bool SQTable::Get(const SQObjectPtr &key,SQObjectPtr &val)
+{
+	if(type(key) == OT_NULL)
+		return false;
+	_HashNode *n = _Get(key, HashObj(key) & (_numofnodes - 1));
+	if (n) {
+		val = _realval(n->val);
+		return true;
+	}
+	return false;
+}
+bool SQTable::NewSlot(const SQObjectPtr &key,const SQObjectPtr &val)
+{
+	assert(type(key) != OT_NULL);
+	SQHash h = HashObj(key) & (_numofnodes - 1);
+	_HashNode *n = _Get(key, h);
+	if (n) {
+		n->val = val;
+		return false;
+	}
+	_HashNode *mp = &_nodes[h];
+	n = mp;
+
+
+	//key not found I'll insert it
+	//main pos is not free
+
+	if(type(mp->key) != OT_NULL) {
+		n = _firstfree;  /* get a free place */
+		SQHash mph = HashObj(mp->key) & (_numofnodes - 1);
+		_HashNode *othern;  /* main position of colliding node */
+		
+		if (mp > n && (othern = &_nodes[mph]) != mp){
+			/* yes; move colliding node into free position */
+			while (othern->next != mp){
+				assert(othern->next != NULL);
+				othern = othern->next;  /* find previous */
+			}
+			othern->next = n;  /* redo the chain with `n' in place of `mp' */
+			n->key = mp->key;
+			n->val = mp->val;/* copy colliding node into free pos. (mp->next also goes) */
+			n->next = mp->next;
+			mp->key.Null();
+			mp->val.Null();
+			mp->next = NULL;  /* now `mp' is free */
+		}
+		else{
+			/* new node will go into free position */
+			n->next = mp->next;  /* chain new position */
+			mp->next = n;
+			mp = n;
+		}
+	}
+	mp->key = key;
+
+	for (;;) {  /* correct `firstfree' */
+		if (type(_firstfree->key) == OT_NULL && _firstfree->next == NULL) {
+			mp->val = val;
+			_usednodes++;
+			return true;  /* OK; table still has a free place */
+		}
+		else if (_firstfree == _nodes) break;  /* cannot decrement from here */
+		else (_firstfree)--;
+	}
+	Rehash(true);
+	return NewSlot(key, val);
+}
+
+SQInteger SQTable::Next(bool getweakrefs,const SQObjectPtr &refpos, SQObjectPtr &outkey, SQObjectPtr &outval)
+{
+	SQInteger idx = (SQInteger)TranslateIndex(refpos);
+	while (idx < _numofnodes) {
+		if(type(_nodes[idx].key) != OT_NULL) {
+			//first found
+			_HashNode &n = _nodes[idx];
+			outkey = n.key;
+			outval = getweakrefs?(SQObject)n.val:_realval(n.val);
+			//return idx for the next iteration
+			return ++idx;
+		}
+		++idx;
+	}
+	//nothing to iterate anymore
+	return -1;
+}
+
+
+bool SQTable::Set(const SQObjectPtr &key, const SQObjectPtr &val)
+{
+	_HashNode *n = _Get(key, HashObj(key) & (_numofnodes - 1));
+	if (n) {
+		n->val = val;
+		return true;
+	}
+	return false;
+}
+
+void SQTable::_ClearNodes()
+{
+	for(SQInteger i = 0;i < _numofnodes; i++) { _HashNode &n = _nodes[i]; n.key.Null(); n.val.Null(); }
+}
+
+void SQTable::Finalize()
+{
+	_ClearNodes();
+	SetDelegate(NULL);
+}
+
+void SQTable::Clear()
+{
+	_ClearNodes();
+	_usednodes = 0;
+	Rehash(true);
+}