nSquirrel/squirrel/sqclass.cpp

/*
	see copyright notice in squirrel.h
*/
#include "sqpcheader.h"
#include "sqvm.h"
#include "sqtable.h"
#include "sqclass.h"
#include "sqfuncproto.h"
#include "sqclosure.h"



SQClass::SQClass(SQSharedState *ss,SQClass *base)
{
	_base = base;
	_typetag = 0;
	_hook = NULL;
	_udsize = 0;
	_locked = false;
	_constructoridx = -1;
	if(_base) {
		_constructoridx = _base->_constructoridx;
		_udsize = _base->_udsize;
		_defaultvalues.copy(base->_defaultvalues);
		_methods.copy(base->_methods);
		_COPY_VECTOR(_metamethods,base->_metamethods,MT_LAST);
		__ObjAddRef(_base);
	}
	_members = base?base->_members->Clone() : SQTable::Create(ss,0);
	__ObjAddRef(_members);
	
	INIT_CHAIN();
	ADD_TO_CHAIN(&_sharedstate->_gc_chain, this);
}

void SQClass::Finalize() { 
	_attributes.Null();
	_NULL_SQOBJECT_VECTOR(_defaultvalues,_defaultvalues.size());
	_methods.resize(0);
	_NULL_SQOBJECT_VECTOR(_metamethods,MT_LAST);
	__ObjRelease(_members);
	if(_base) {
		__ObjRelease(_base);
	}
}

SQClass::~SQClass()
{
	REMOVE_FROM_CHAIN(&_sharedstate->_gc_chain, this);
	Finalize();
}

bool SQClass::NewSlot(SQSharedState *ss,const SQObjectPtr &key,const SQObjectPtr &val,bool bstatic)
{
	SQObjectPtr temp;
	bool belongs_to_static_table = type(val) == OT_CLOSURE || type(val) == OT_NATIVECLOSURE || bstatic;
	if(_locked && !belongs_to_static_table) 
		return false; //the class already has an instance so cannot be modified
	if(_members->Get(key,temp) && _isfield(temp)) //overrides the default value
	{
		_defaultvalues[_member_idx(temp)].val = val;
		return true;
	}
	if(belongs_to_static_table) {
		SQInteger mmidx;
		if((type(val) == OT_CLOSURE || type(val) == OT_NATIVECLOSURE) && 
			(mmidx = ss->GetMetaMethodIdxByName(key)) != -1) {
			_metamethods[mmidx] = val;
		} 
		else {
			SQObjectPtr theval = val;
			if(_base && type(val) == OT_CLOSURE) {
				theval = _closure(val)->Clone();
				_closure(theval)->_base = _base;
				__ObjAddRef(_base); //ref for the closure
			}
			if(type(temp) == OT_NULL) {
				bool isconstructor;
				SQVM::IsEqual(ss->_constructoridx, key, isconstructor);
				if(isconstructor) {
					_constructoridx = (SQInteger)_methods.size();
				}
				SQClassMember m;
				m.val = theval;
				_members->NewSlot(key,SQObjectPtr(_make_method_idx(_methods.size())));
				_methods.push_back(m);
			}
			else {
				_methods[_member_idx(temp)].val = theval;
			}
		}
		return true;
	}
	SQClassMember m;
	m.val = val;
	_members->NewSlot(key,SQObjectPtr(_make_field_idx(_defaultvalues.size())));
	_defaultvalues.push_back(m);
	return true;
}

SQInstance *SQClass::CreateInstance()
{
	if(!_locked) Lock();
	return SQInstance::Create(_opt_ss(this),this);
}

SQInteger SQClass::Next(const SQObjectPtr &refpos, SQObjectPtr &outkey, SQObjectPtr &outval)
{
	SQObjectPtr oval;
	SQInteger idx = _members->Next(false,refpos,outkey,oval);
	if(idx != -1) {
		if(_ismethod(oval)) {
			outval = _methods[_member_idx(oval)].val;
		}
		else {
			SQObjectPtr &o = _defaultvalues[_member_idx(oval)].val;
			outval = _realval(o);
		}
	}
	return idx;
}

bool SQClass::SetAttributes(const SQObjectPtr &key,const SQObjectPtr &val)
{
	SQObjectPtr idx;
	if(_members->Get(key,idx)) {
		if(_isfield(idx))
			_defaultvalues[_member_idx(idx)].attrs = val;
		else
			_methods[_member_idx(idx)].attrs = val;
		return true;
	}
	return false;
}

bool SQClass::GetAttributes(const SQObjectPtr &key,SQObjectPtr &outval)
{
	SQObjectPtr idx;
	if(_members->Get(key,idx)) {
		outval = (_isfield(idx)?_defaultvalues[_member_idx(idx)].attrs:_methods[_member_idx(idx)].attrs);
		return true;
	}
	return false;
}

///////////////////////////////////////////////////////////////////////
void SQInstance::Init(SQSharedState *ss)
{
	_userpointer = NULL;
	_hook = NULL;
	__ObjAddRef(_class);
	_delegate = _class->_members;
	INIT_CHAIN();
	ADD_TO_CHAIN(&_sharedstate->_gc_chain, this);
}

SQInstance::SQInstance(SQSharedState *ss, SQClass *c, SQInteger memsize)
{
	_memsize = memsize;
	_class = c;
	SQUnsignedInteger nvalues = _class->_defaultvalues.size();
	for(SQUnsignedInteger n = 0; n < nvalues; n++) {
		new (&_values[n]) SQObjectPtr(_class->_defaultvalues[n].val);
	}
	Init(ss);
}

SQInstance::SQInstance(SQSharedState *ss, SQInstance *i, SQInteger memsize)
{
	_memsize = memsize;
	_class = i->_class;
	SQUnsignedInteger nvalues = _class->_defaultvalues.size();
	for(SQUnsignedInteger n = 0; n < nvalues; n++) {
		new (&_values[n]) SQObjectPtr(i->_values[n]);
	}
	Init(ss);
}

void SQInstance::Finalize() 
{
	SQUnsignedInteger nvalues = _class->_defaultvalues.size();
	__ObjRelease(_class);
	_NULL_SQOBJECT_VECTOR(_values,nvalues);
}

SQInstance::~SQInstance()
{
	REMOVE_FROM_CHAIN(&_sharedstate->_gc_chain, this);
	if(_class){ Finalize(); } //if _class is null it was already finalized by the GC
}

bool SQInstance::GetMetaMethod(SQVM *v,SQMetaMethod mm,SQObjectPtr &res)
{
	if(type(_class->_metamethods[mm]) != OT_NULL) {
		res = _class->_metamethods[mm];
		return true;
	}
	return false;
}

bool SQInstance::InstanceOf(SQClass *trg)
{
	SQClass *parent = _class;
	while(parent != NULL) {
		if(parent == trg)
			return true;
		parent = parent->_base;
	}
	return false;
}