scummvm/engines/sci/engine/object.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#ifndef SCI_ENGINE_OBJECT_H
#define SCI_ENGINE_OBJECT_H

#include "common/array.h"
#include "common/serializer.h"
#include "common/textconsole.h"

#include "sci/sci.h"			// for the SCI versions
#include "sci/engine/vm_types.h"	// for reg_t
#include "sci/util.h"

namespace Sci {

class SegManager;

/** Clone has been marked as 'freed' */
enum {
	OBJECT_FLAG_FREED = (1 << 0)
};

enum infoSelectorFlags {
	kInfoFlagClone = 0x0001,
	kInfoFlagClass = 0x8000
};

enum ObjectOffsets {
	kOffsetLocalVariables = -6,
	kOffsetFunctionArea = -4,
	kOffsetSelectorCounter = -2,
	kOffsetSelectorSegment = 0,
	kOffsetInfoSelectorSci0 = 4,
	kOffsetNamePointerSci0 = 6,
	kOffsetInfoSelectorSci11 = 14,
	kOffsetNamePointerSci11 = 16
};

class Object {
public:
	Object() {
		_offset = getSciVersion() < SCI_VERSION_1_1 ? 0 : 5;
		_flags = 0;
		_baseObj = 0;
		_baseVars = 0;
		_methodCount = 0;
		_propertyOffsetsSci3 = 0;
	}

	~Object() {
		if (getSciVersion() == SCI_VERSION_3) {
			// FIXME: memory leak! Commented out because of reported heap
			// corruption by MSVC (e.g. in LSL7, when it starts)
			//free(_baseVars);
			//_baseVars = 0;
			//free(_propertyOffsetsSci3);
			//_propertyOffsetsSci3 = 0;
		}
	}

	reg_t getSpeciesSelector() const {
		if (getSciVersion() <= SCI_VERSION_2_1) 
			return _variables[_offset];
		else	// SCI3
			return _speciesSelectorSci3;
	}

	void setSpeciesSelector(reg_t value) {
		if (getSciVersion() <= SCI_VERSION_2_1)
			_variables[_offset] = value;
		else	// SCI3
			_speciesSelectorSci3 = value;
	}

	reg_t getSuperClassSelector() const {
		if (getSciVersion() <= SCI_VERSION_2_1) 
			return _variables[_offset + 1];
		else	// SCI3
			return _superClassPosSci3;
	}

	void setSuperClassSelector(reg_t value) {
		if (getSciVersion() <= SCI_VERSION_2_1)
			_variables[_offset + 1] = value;
		else	// SCI3
			_superClassPosSci3 = value;
	}

	reg_t getInfoSelector() const {
		if (getSciVersion() <= SCI_VERSION_2_1)
			return _variables[_offset + 2];
		else	// SCI3
			return _infoSelectorSci3;
	}

	void setInfoSelector(reg_t info) {
		if (getSciVersion() <= SCI_VERSION_2_1)
			_variables[_offset + 2] = info;
		else	// SCI3
			_infoSelectorSci3 = info;
	}

	// No setter for the -info- selector

	reg_t getNameSelector() const {
		if (getSciVersion() <= SCI_VERSION_2_1)
			return _offset + 3 < (uint16)_variables.size() ? _variables[_offset + 3] : NULL_REG;
		else	// SCI3
			return _variables.size() ? _variables[0] : NULL_REG;
	}

	// No setter for the name selector

	reg_t getPropDictSelector() const {
		if (getSciVersion() <= SCI_VERSION_2_1)
			return _variables[2];
		else
			// This should never occur, this is called from a SCI1.1 - SCI2.1 only function
			error("getPropDictSelector called for SCI3");
	}

	void setPropDictSelector(reg_t value) {
		if (getSciVersion() <= SCI_VERSION_2_1)
			_variables[2] = value;
		else
			// This should never occur, this is called from a SCI1.1 - SCI2.1 only function
			error("setPropDictSelector called for SCI3");
	}

	reg_t getClassScriptSelector() const {
		if (getSciVersion() <= SCI_VERSION_2_1)
			return _variables[4];
		else	// SCI3
			return make_reg(0, READ_SCI11ENDIAN_UINT16(_baseObj + 6));
	}

	void setClassScriptSelector(reg_t value) {
		if (getSciVersion() <= SCI_VERSION_2_1)
			_variables[4] = value;
		else	// SCI3
			// This should never occur, this is called from a SCI1.1 - SCI2.1 only function
			error("setClassScriptSelector called for SCI3");
	}

	Selector getVarSelector(uint16 i) const { return READ_SCI11ENDIAN_UINT16(_baseVars + i); }

	reg_t getFunction(uint16 i) const {
		uint16 offset = (getSciVersion() < SCI_VERSION_1_1) ? _methodCount + 1 + i : i * 2 + 2;
		if (getSciVersion() == SCI_VERSION_3)
			offset--;
		return make_reg(_pos.segment, _baseMethod[offset]);
	}

	Selector getFuncSelector(uint16 i) const {
		uint16 offset = (getSciVersion() < SCI_VERSION_1_1) ? i : i * 2 + 1;
		if (getSciVersion() == SCI_VERSION_3)
			offset--;
		return _baseMethod[offset];
	}

	/**
	 * Determines if this object is a class and explicitly defines the
	 * selector as a funcselector. Does NOT say anything about the object's
	 * superclasses, i.e. failure may be returned even if one of the
	 * superclasses defines the funcselector
	 */
	int funcSelectorPosition(Selector sel) const {
		for (uint i = 0; i < _methodCount; i++)
			if (getFuncSelector(i) == sel)
				return i;

		return -1;
	}

	/**
	 * Determines if the object explicitly defines slc as a varselector.
	 * Returns -1 if not found.
	 */
	int locateVarSelector(SegManager *segMan, Selector slc) const;

	bool isClass() const { return (getInfoSelector().offset & kInfoFlagClass); }
	const Object *getClass(SegManager *segMan) const;

	void markAsFreed() { _flags |= OBJECT_FLAG_FREED; }
	bool isFreed() const { return _flags & OBJECT_FLAG_FREED; }

	uint getVarCount() const { return _variables.size(); }

	void init(byte *buf, reg_t obj_pos, bool initVariables = true);

	reg_t getVariable(uint var) const { return _variables[var]; }
	reg_t &getVariableRef(uint var) { return _variables[var]; }

	uint16 getMethodCount() const { return _methodCount; }
	reg_t getPos() const { return _pos; }

	void saveLoadWithSerializer(Common::Serializer &ser);

	void cloneFromObject(const Object *obj) {
		_baseObj = obj ? obj->_baseObj : NULL;
		_baseMethod = obj ? obj->_baseMethod : Common::Array<uint16>();
		_baseVars = obj ? obj->_baseVars : NULL;
	}

	bool relocateSci0Sci21(SegmentId segment, int location, size_t scriptSize);
	bool relocateSci3(SegmentId segment, int location, int offset, size_t scriptSize);

	int propertyOffsetToId(SegManager *segMan, int propertyOffset) const;

	void initSpecies(SegManager *segMan, reg_t addr);
	void initSuperClass(SegManager *segMan, reg_t addr);
	bool initBaseObject(SegManager *segMan, reg_t addr, bool doInitSuperClass = true);
	void syncBaseObject(const byte *ptr) { _baseObj = ptr; }

private:
	void initSelectorsSci3(const byte *buf);

	const byte *_baseObj; /**< base + object offset within base */
	uint16 *_baseVars; /**< Pointer to the varselector area for this object */
	Common::Array<uint16> _baseMethod; /**< Pointer to the method selector area for this object */
	uint16 *_propertyOffsetsSci3; /**< This is used to enable relocation of property valuesa in SCI3 */

	Common::Array<reg_t> _variables;
	uint16 _methodCount;
	int _flags;
	uint16 _offset;
	reg_t _pos; /**< Object offset within its script; for clones, this is their base */
	reg_t _superClassPosSci3; /**< reg_t pointing to superclass for SCI3 */
	reg_t _speciesSelectorSci3;	/**< reg_t containing species "selector" for SCI3 */
	reg_t _infoSelectorSci3; /**< reg_t containing info "selector" for SCI3 */
};


} // End of namespace Sci

#endif // SCI_ENGINE_OBJECT_H