TESTBED: Merged changes from trunk to my branch

svn-id: r51798

1 files changed, 462 insertions, 332 deletions

diff --git a/engines/sci/engine/script.cpp b/engines/sci/engine/script.cpp
index 1f32e50b67..645094d9ec 100644
--- a/engines/sci/engine/script.cpp
+++ b/engines/sci/engine/script.cpp
@@ -35,431 +35,561 @@
 
 namespace Sci {
 
-#define END Script_None
-
-opcode_format g_opcode_formats[128][4] = {
-	/*00*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_None},
-	/*04*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_None},
-	/*08*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_None},
-	/*0C*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_None},
-	/*10*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_None},
-	/*14*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_SRelative, END},
-	/*18*/
-	{Script_SRelative, END}, {Script_SRelative, END}, {Script_SVariable, END}, {Script_None},
-	/*1C*/
-	{Script_SVariable, END}, {Script_None}, {Script_None}, {Script_Variable, END},
-	/*20*/
-	{Script_SRelative, Script_Byte, END}, {Script_Variable, Script_Byte, END}, {Script_Variable, Script_Byte, END}, {Script_Variable, Script_SVariable, Script_Byte, END},
-	/*24 (24=ret)*/
-	{Script_End}, {Script_Byte, END}, {Script_Invalid}, {Script_Invalid},
-	/*28*/
-	{Script_Variable, END}, {Script_Invalid}, {Script_Byte, END}, {Script_Variable, Script_Byte, END},
-	/*2C*/
-	{Script_SVariable, END}, {Script_SVariable, Script_Variable, END}, {Script_None}, {Script_Invalid},
-	/*30*/
-	{Script_None}, {Script_Property, END}, {Script_Property, END}, {Script_Property, END},
-	/*34*/
-	{Script_Property, END}, {Script_Property, END}, {Script_Property, END}, {Script_Property, END},
-	/*38*/
-	{Script_Property, END}, {Script_SRelative, END}, {Script_SRelative, END}, {Script_None},
-	/*3C*/
-	{Script_None}, {Script_None}, {Script_None}, {Script_Word},
-	/*40-4F*/
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	/*50-5F*/
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	/*60-6F*/
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	/*70-7F*/
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END},
-	{Script_Global, END}, {Script_Local, END}, {Script_Temp, END}, {Script_Param, END}
-};
-#undef END
-
-// TODO: script_adjust_opcode_formats should probably be part of the
-// constructor (?) of a VirtualMachine or a ScriptManager class.
-void script_adjust_opcode_formats(EngineState *s) {
-	// TODO: Check that this is correct
-	if (g_sci->_features->detectLofsType() != SCI_VERSION_0_EARLY) {
-		g_opcode_formats[op_lofsa][0] = Script_Offset;
-		g_opcode_formats[op_lofss][0] = Script_Offset;
-	}
+Script::Script() : SegmentObj(SEG_TYPE_SCRIPT) {
+	_nr = 0;
+	_buf = NULL;
+	_bufSize = 0;
+	_scriptSize = 0;
+	_heapSize = 0;
+
+	_synonyms = NULL;
+	_heapStart = NULL;
+	_exportTable = NULL;
+
+	_localsOffset = 0;
+	_localsSegment = 0;
+	_localsBlock = NULL;
+	_localsCount = 0;
+
+	_markedAsDeleted = false;
+}
+
+Script::~Script() {
+	freeScript();
+}
+
+void Script::freeScript() {
+	free(_buf);
+	_buf = NULL;
+	_bufSize = 0;
 
-#ifdef ENABLE_SCI32
-	// In SCI32, some arguments are now words instead of bytes
-	if (getSciVersion() >= SCI_VERSION_2) {
-		g_opcode_formats[op_calle][2] = Script_Word;
-		g_opcode_formats[op_callk][1] = Script_Word;
-		g_opcode_formats[op_super][1] = Script_Word;
-		g_opcode_formats[op_send][0] = Script_Word;
-		g_opcode_formats[op_self][0] = Script_Word;
-		g_opcode_formats[op_call][1] = Script_Word;
-		g_opcode_formats[op_callb][1] = Script_Word;
+	_objects.clear();
+}
+
+void Script::init(int script_nr, ResourceManager *resMan) {
+	Resource *script = resMan->findResource(ResourceId(kResourceTypeScript, script_nr), 0);
+
+	_localsOffset = 0;
+	_localsBlock = NULL;
+	_localsCount = 0;
+
+	_markedAsDeleted = false;
+
+	_nr = script_nr;
+	_buf = 0;
+	_heapStart = 0;
+
+	_scriptSize = script->size;
+	_bufSize = script->size;
+	_heapSize = 0;
+
+	_lockers = 1;
+
+	if (getSciVersion() == SCI_VERSION_0_EARLY) {
+		_bufSize += READ_LE_UINT16(script->data) * 2;
+	} else if (getSciVersion() >= SCI_VERSION_1_1) {
+		// In SCI11, the heap was in a separate space from the script. We append
+		// it to the end of the script, and adjust addressing accordingly.
+		// However, since we address the heap with a 16-bit pointer, the
+		// combined size of the stack and the heap must be 64KB. So far this has
+		// worked for SCI11, SCI2 and SCI21 games. SCI3 games use a different
+		// script format, and theoretically they can exceed the 64KB boundary
+		// using relocation.
+		Resource *heap = resMan->findResource(ResourceId(kResourceTypeHeap, script_nr), 0);
+		_bufSize += heap->size;
+		_heapSize = heap->size;
+
+		// Ensure that the start of the heap resource can be word-aligned.
+		if (script->size & 2) {
+			_bufSize++;
+			_scriptSize++;
+		}
+
+		// As mentioned above, the script and the heap together should not exceed 64KB
+		if (script->size + heap->size > 65535)
+			error("Script and heap sizes combined exceed 64K. This means a fundamental "
+					"design bug was made regarding SCI1.1 and newer games.\n"
+					"Please report this error to the ScummVM team");
 	}
-#endif
 }
 
-void SegManager::createClassTable() {
-	Resource *vocab996 = _resMan->findResource(ResourceId(kResourceTypeVocab, 996), 1);
+void Script::load(ResourceManager *resMan) {
+	Resource *script = resMan->findResource(ResourceId(kResourceTypeScript, _nr), 0);
+	assert(script != 0);
 
-	if (!vocab996)
-		error("SegManager: failed to open vocab 996");
+	_buf = (byte *)malloc(_bufSize);
+	assert(_buf);
 
-	int totalClasses = vocab996->size >> 2;
-	_classTable.resize(totalClasses);
+	assert(_bufSize >= script->size);
+	memcpy(_buf, script->data, script->size);
+
+	if (getSciVersion() >= SCI_VERSION_1_1) {
+		Resource *heap = resMan->findResource(ResourceId(kResourceTypeHeap, _nr), 0);
+		assert(heap != 0);
 
-	for (uint16 classNr = 0; classNr < totalClasses; classNr++) {
-		uint16 scriptNr = READ_SCI11ENDIAN_UINT16(vocab996->data + classNr * 4 + 2);
+		_heapStart = _buf + _scriptSize;
 
-		_classTable[classNr].reg = NULL_REG;
-		_classTable[classNr].script = scriptNr;
+		assert(_bufSize - _scriptSize <= heap->size);
+		memcpy(_heapStart, heap->data, heap->size);
 	}
 
-	_resMan->unlockResource(vocab996);
-}
+	_exportTable = 0;
+	_numExports = 0;
+	_synonyms = 0;
+	_numSynonyms = 0;
+	
+	if (getSciVersion() >= SCI_VERSION_1_1) {
+		if (READ_LE_UINT16(_buf + 1 + 5) > 0) {	// does the script have an export table?
+			_exportTable = (const uint16 *)(_buf + 1 + 5 + 2);
+			_numExports = READ_SCI11ENDIAN_UINT16(_exportTable - 1);
+		}
+		_localsOffset = _scriptSize + 4;
+		_localsCount = READ_SCI11ENDIAN_UINT16(_buf + _localsOffset - 2);
+	} else {
+		_exportTable = (const uint16 *)findBlock(SCI_OBJ_EXPORTS);
+		if (_exportTable) {
+			_numExports = READ_SCI11ENDIAN_UINT16(_exportTable + 1);
+			_exportTable += 3;	// skip header plus 2 bytes (_exportTable is a uint16 pointer)
+		}
+		_synonyms = findBlock(SCI_OBJ_SYNONYMS);
+		if (_synonyms) {
+			_numSynonyms = READ_SCI11ENDIAN_UINT16(_synonyms + 2) / 4;
+			_synonyms += 4;	// skip header
+		}
+		const byte* localsBlock = findBlock(SCI_OBJ_LOCALVARS);
+		if (localsBlock) {
+			_localsOffset = localsBlock - _buf + 4;
+			_localsCount = (READ_LE_UINT16(_buf + _localsOffset - 2) - 4) >> 1;	// half block size
+		}
+	}
 
-reg_t SegManager::getClassAddress(int classnr, ScriptLoadType lock, reg_t caller) {
-	if (classnr == 0xffff)
-		return NULL_REG;
+	if (getSciVersion() > SCI_VERSION_0_EARLY) {
+		// Does the script actually have locals? If not, set the locals offset to 0
+		if (!_localsCount)
+			_localsOffset = 0;
 
-	if (classnr < 0 || (int)_classTable.size() <= classnr || _classTable[classnr].script < 0) {
-		error("[VM] Attempt to dereference class %x, which doesn't exist (max %x)", classnr, _classTable.size());
-		return NULL_REG;
+		if (_localsOffset + _localsCount * 2 + 1 >= (int)_bufSize) {
+			error("Locals extend beyond end of script: offset %04x, count %d vs size %d", _localsOffset, _localsCount, _bufSize);
+			_localsCount = (_bufSize - _localsOffset) >> 1;
+		}
 	} else {
-		Class *the_class = &_classTable[classnr];
-		if (!the_class->reg.segment) {
-			getScriptSegment(the_class->script, lock);
+		// Old script block. There won't be a localvar block in this case.
+		// Instead, the script starts with a 16 bit int specifying the
+		// number of locals we need; these are then allocated and zeroed.
+		_localsCount = READ_LE_UINT16(_buf);
+		_localsOffset = -_localsCount * 2; // Make sure it's invalid
+	}
+}
 
-			if (!the_class->reg.segment) {
-				error("[VM] Trying to instantiate class %x by instantiating script 0x%x (%03d) failed;", classnr, the_class->script, the_class->script);
-				return NULL_REG;
-			}
-		} else
-			if (caller.segment != the_class->reg.segment)
-				getScript(the_class->reg.segment)->incrementLockers();
+Object *Script::getObject(uint16 offset) {
+	if (_objects.contains(offset))
+		return &_objects[offset];
+	else
+		return 0;
+}
 
-		return the_class->reg;
-	}
+const Object *Script::getObject(uint16 offset) const {
+	if (_objects.contains(offset))
+		return &_objects[offset];
+	else
+		return 0;
 }
 
-void SegManager::scriptInitialiseLocalsZero(SegmentId seg, int count) {
-	Script *scr = getScript(seg);
+Object *Script::scriptObjInit(reg_t obj_pos, bool fullObjectInit) {
+	if (getSciVersion() < SCI_VERSION_1_1 && fullObjectInit)
+		obj_pos.offset += 8;	// magic offset (SCRIPT_OBJECT_MAGIC_OFFSET)
 
-	scr->_localsOffset = -count * 2; // Make sure it's invalid
+	VERIFY(obj_pos.offset < _bufSize, "Attempt to initialize object beyond end of script\n");
 
-	LocalVariables *locals = allocLocalsSegment(scr, count);
-	if (locals) {
-		for (int i = 0; i < count; i++)
-			locals->_locals[i] = NULL_REG;
-	}
+	VERIFY(obj_pos.offset + kOffsetFunctionArea < (int)_bufSize, "Function area pointer stored beyond end of script\n");
+
+	// Get the object at the specified position and init it. This will
+	// automatically "allocate" space for it in the _objects map if necessary.
+	Object *obj = &_objects[obj_pos.offset];
+	obj->init(_buf, obj_pos, fullObjectInit);
+
+	return obj;
 }
 
-void SegManager::scriptInitialiseLocals(reg_t location) {
-	Script *scr = getScript(location.segment);
-	unsigned int count;
+void Script::scriptObjRemove(reg_t obj_pos) {
+	if (getSciVersion() < SCI_VERSION_1_1)
+		obj_pos.offset += 8;
 
-	VERIFY(location.offset + 1 < (uint16)scr->getBufSize(), "Locals beyond end of script\n");
+	_objects.erase(obj_pos.toUint16());
+}
 
-	if (getSciVersion() >= SCI_VERSION_1_1)
-		count = READ_SCI11ENDIAN_UINT16(scr->_buf + location.offset - 2);
-	else
-		count = (READ_LE_UINT16(scr->_buf + location.offset - 2) - 4) >> 1;
-	// half block size
+// This helper function is used by Script::relocateLocal and Object::relocate
+// Duplicate in segment.cpp and script.cpp
+static bool relocateBlock(Common::Array<reg_t> &block, int block_location, SegmentId segment, int location, size_t scriptSize) {
+	int rel = location - block_location;
 
-	scr->_localsOffset = location.offset;
+	if (rel < 0)
+		return false;
 
-	if (!(location.offset + count * 2 + 1 < scr->getBufSize())) {
-		warning("Locals extend beyond end of script: offset %04x, count %x vs size %x", location.offset, count, (uint)scr->getBufSize());
-		count = (scr->getBufSize() - location.offset) >> 1;
-	}
+	uint idx = rel >> 1;
 
-	LocalVariables *locals = allocLocalsSegment(scr, count);
-	if (locals) {
-		uint i;
-		const byte *base = (const byte *)(scr->_buf + location.offset);
+	if (idx >= block.size())
+		return false;
 
-		for (i = 0; i < count; i++)
-			locals->_locals[i] = make_reg(0, READ_SCI11ENDIAN_UINT16(base + i * 2));
+	if (rel & 1) {
+		error("Attempt to relocate odd variable #%d.5e (relative to %04x)\n", idx, block_location);
+		return false;
 	}
+	block[idx].segment = segment; // Perform relocation
+	if (getSciVersion() >= SCI_VERSION_1_1)
+		block[idx].offset += scriptSize;
+
+	return true;
 }
 
-void SegManager::scriptInitialiseObjectsSci11(SegmentId seg) {
-	Script *scr = getScript(seg);
-	const byte *seeker = scr->_heapStart + 4 + READ_SCI11ENDIAN_UINT16(scr->_heapStart + 2) * 2;
+bool Script::relocateLocal(SegmentId segment, int location) {
+	if (_localsBlock)
+		return relocateBlock(_localsBlock->_locals, _localsOffset, segment, location, _scriptSize);
+	else
+		return false;
+}
 
-	while (READ_SCI11ENDIAN_UINT16(seeker) == SCRIPT_OBJECT_MAGIC_NUMBER) {
-		if (READ_SCI11ENDIAN_UINT16(seeker + 14) & kInfoFlagClass) {	// -info- selector
-			int classpos = seeker - scr->_buf;
-			int species = READ_SCI11ENDIAN_UINT16(seeker + 10);
-
-			if (species < 0 || species >= (int)_classTable.size()) {
-				error("Invalid species %d(0x%x) not in interval [0,%d) while instantiating script %d",
-				          species, species, _classTable.size(), scr->_nr);
-				return;
-			}
+void Script::relocate(reg_t block) {
+	const byte *heap = _buf;
+	uint16 heapSize = (uint16)_bufSize;
+	uint16 heapOffset = 0;
 
-			_classTable[species].reg.segment = seg;
-			_classTable[species].reg.offset = classpos;
-		}
-		seeker += READ_SCI11ENDIAN_UINT16(seeker + 2) * 2;
+	if (getSciVersion() >= SCI_VERSION_1_1) {
+		heap = _heapStart;
+		heapSize = (uint16)_heapSize;
+		heapOffset = _scriptSize;
 	}
 
-	seeker = scr->_heapStart + 4 + READ_SCI11ENDIAN_UINT16(scr->_heapStart + 2) * 2;
-	while (READ_SCI11ENDIAN_UINT16(seeker) == SCRIPT_OBJECT_MAGIC_NUMBER) {
-		reg_t reg = make_reg(seg, seeker - scr->_buf);
-		Object *obj = scr->scriptObjInit(reg);
-
-		// Copy base from species class, as we need its selector IDs
-		obj->setSuperClassSelector(
-			getClassAddress(obj->getSuperClassSelector().offset, SCRIPT_GET_LOCK, NULL_REG));
-
-		// If object is instance, get -propDict- from class and set it for this object
-		//  This is needed for ::isMemberOf() to work.
-		// Example testcase - room 381 of sq4cd - if isMemberOf() doesn't work, talk-clicks on the robot will act like
-		//                     clicking on ego
-		if (!obj->isClass()) {
-			reg_t classObject = obj->getSuperClassSelector();
-			Object *classObj = getObject(classObject);
-			obj->setPropDictSelector(classObj->getPropDictSelector());
+	VERIFY(block.offset < (uint16)heapSize && READ_SCI11ENDIAN_UINT16(heap + block.offset) * 2 + block.offset < (uint16)heapSize,
+	       "Relocation block outside of script\n");
+
+	int count = READ_SCI11ENDIAN_UINT16(heap + block.offset);
+	int exportIndex = 0;
+	int pos = 0;
+
+	for (int i = 0; i < count; i++) {
+		pos = READ_SCI11ENDIAN_UINT16(heap + block.offset + 2 + (exportIndex * 2)) + heapOffset;
+		// This occurs in SCI01/SCI1 games where usually one export value is
+		// zero. It seems that in this situation, we should skip the export and
+		// move to the next one, though the total count of valid exports remains
+		// the same
+		if (!pos) {
+			exportIndex++;
+			pos = READ_SCI11ENDIAN_UINT16(heap + block.offset + 2 + (exportIndex * 2)) + heapOffset;
+			if (!pos)
+				error("Script::relocate(): Consecutive zero exports found");
 		}
 
-		// Set the -classScript- selector to the script number.
-		// FIXME: As this selector is filled in at run-time, it is likely
-		// that it is supposed to hold a pointer. The Obj::isKindOf method
-		// uses this selector together with -propDict- to compare classes.
-		// For the purpose of Obj::isKindOf, using the script number appears
-		// to be sufficient.
-		obj->setClassScriptSelector(make_reg(0, scr->_nr));
+		// In SCI0-SCI1, script local variables, objects and code are relocated.
+		// We only relocate locals and objects here, and ignore relocation of
+		// code blocks. In SCI1.1 and newer versions, only locals and objects
+		// are relocated.
+		if (!relocateLocal(block.segment, pos)) {
+			// Not a local? It's probably an object or code block. If it's an object, relocate it.
+			const ObjMap::iterator end = _objects.end();
+			for (ObjMap::iterator it = _objects.begin(); it != end; ++it)
+				if (it->_value.relocate(block.segment, pos, _scriptSize))
+					break;
+		}
 
-		seeker += READ_SCI11ENDIAN_UINT16(seeker + 2) * 2;
+		exportIndex++;
 	}
 }
 
-void script_instantiate_sci0(Script *scr, int segmentId, SegManager *segMan) {
-	int objType;
-	uint32 objLength = 0;
-	bool oldScriptHeader = (getSciVersion() == SCI_VERSION_0_EARLY);
-	uint16 curOffset = oldScriptHeader ? 2 : 0;
+void Script::incrementLockers() {
+	_lockers++;
+}
 
-	if (oldScriptHeader) {
-		// Old script block
-		// There won't be a localvar block in this case
-		// Instead, the script starts with a 16 bit int specifying the
-		// number of locals we need; these are then allocated and zeroed.
-		int localsCount = READ_LE_UINT16(scr->_buf);
-		if (localsCount)
-			segMan->scriptInitialiseLocalsZero(segmentId, localsCount);
-	}
+void Script::decrementLockers() {
+	if (_lockers > 0)
+		_lockers--;
+}
 
-	// Now do a first pass through the script objects to find the
-	// local variable blocks
+int Script::getLockers() const {
+	return _lockers;
+}
 
-	do {
-		objType = scr->getHeap(curOffset);
-		if (!objType)
-			break;
+void Script::setLockers(int lockers) {
+	_lockers = lockers;
+}
 
-		objLength = scr->getHeap(curOffset + 2);
-		curOffset += 4;		// skip header
+uint16 Script::validateExportFunc(int pubfunct) {
+	bool exportsAreWide = (g_sci->_features->detectLofsType() == SCI_VERSION_1_MIDDLE);
 
-		switch (objType) {
-		case SCI_OBJ_LOCALVARS:
-			segMan->scriptInitialiseLocals(make_reg(segmentId, curOffset));
-			break;
-		case SCI_OBJ_CLASS: {
-			int classpos = curOffset - SCRIPT_OBJECT_MAGIC_OFFSET;
-			int species = scr->getHeap(curOffset - SCRIPT_OBJECT_MAGIC_OFFSET + SCRIPT_SPECIES_OFFSET);
-			if (species < 0 || species >= (int)segMan->classTableSize()) {
-				if (species == (int)segMan->classTableSize()) {
-					// Happens in the LSL2 demo
-					warning("Applying workaround for an off-by-one invalid species access");
-					segMan->resizeClassTable(segMan->classTableSize() + 1);
-				} else {
-					error("Invalid species %d(0x%x) not in interval "
-							  "[0,%d) while instantiating script at segment %d\n",
-							  species, species, segMan->classTableSize(),
-							  segmentId);
-					return;
-				}
-			}
+	if (_numExports <= pubfunct) {
+		error("validateExportFunc(): pubfunct is invalid");
+		return 0;
+	}
 
-			segMan->setClassOffset(species, make_reg(segmentId, classpos));
-			// Set technical class position-- into the block allocated for it
-		}
-		break;
+	if (exportsAreWide)
+		pubfunct *= 2;
+	uint16 offset = READ_SCI11ENDIAN_UINT16(_exportTable + pubfunct);
+	VERIFY(offset < _bufSize, "invalid export function pointer");
 
-		default:
-			break;
-		}
+	return offset;
+}
 
-		curOffset += objLength - 4;
-	} while (objType != 0 && curOffset < scr->getScriptSize() - 2);
+byte *Script::findBlock(int type) {
+	byte *buf = _buf;
+	bool oldScriptHeader = (getSciVersion() == SCI_VERSION_0_EARLY);
 
-	// And now a second pass to adjust objects and class pointers, and the general pointers
-	objLength = 0;
-	curOffset = oldScriptHeader ? 2 : 0;
+	if (oldScriptHeader)
+		buf += 2;
 
 	do {
-		objType = scr->getHeap(curOffset);
-		if (!objType)
+		int seekerType = READ_LE_UINT16(buf);
+
+		if (seekerType == 0)
 			break;
+		if (seekerType == type)
+			return buf;
 
-		objLength = scr->getHeap(curOffset + 2);
-		curOffset += 4;		// skip header
+		int seekerSize = READ_LE_UINT16(buf + 2);
+		assert(seekerSize > 0);
+		buf += seekerSize;
+	} while (1);
 
-		reg_t addr = make_reg(segmentId, curOffset);
+	return NULL;
+}
 
-		switch (objType) {
-		case SCI_OBJ_CODE:
-			scr->scriptAddCodeBlock(addr);
-			break;
-		case SCI_OBJ_OBJECT:
-		case SCI_OBJ_CLASS: { // object or class?
-			Object *obj = scr->scriptObjInit(addr);
-			obj->initSpecies(segMan, addr);
+// memory operations
 
-			if (!obj->initBaseObject(segMan, addr)) {
-				warning("Failed to locate base object for object at %04X:%04X; skipping", PRINT_REG(addr));
-				scr->scriptObjRemove(addr);
-			}
-		} // if object or class
-		break;
-		default:
-			break;
-		}
+void Script::mcpyInOut(int dst, const void *src, size_t n) {
+	if (_buf) {
+		assert(dst + n <= _bufSize);
+		memcpy(_buf + dst, src, n);
+	}
+}
 
-		curOffset += objLength - 4;
-	} while (objType != 0 && curOffset < scr->getScriptSize() - 2);
+bool Script::isValidOffset(uint16 offset) const {
+	return offset < _bufSize;
 }
 
-int script_instantiate(ResourceManager *resMan, SegManager *segMan, int scriptNum) {
-	SegmentId segmentId = segMan->getScriptSegment(scriptNum);
-	Script *scr = segMan->getScriptIfLoaded(segmentId);
-	if (scr) {
-		if (!scr->isMarkedAsDeleted()) {
-			scr->incrementLockers();
-			return segmentId;
+SegmentRef Script::dereference(reg_t pointer) {
+	if (pointer.offset > _bufSize) {
+		error("Script::dereference(): Attempt to dereference invalid pointer %04x:%04x into script segment (script size=%d)",
+				  PRINT_REG(pointer), (uint)_bufSize);
+		return SegmentRef();
+	}
+
+	SegmentRef ret;
+	ret.isRaw = true;
+	ret.maxSize = _bufSize - pointer.offset;
+	ret.raw = _buf + pointer.offset;
+	return ret;
+}
+
+void Script::initialiseLocals(SegManager *segMan) {
+	LocalVariables *locals = segMan->allocLocalsSegment(this);
+	if (locals) {
+		if (getSciVersion() > SCI_VERSION_0_EARLY) {
+			const byte *base = (const byte *)(_buf + getLocalsOffset());
+
+			for (uint16 i = 0; i < getLocalsCount(); i++)
+				locals->_locals[i] = make_reg(0, READ_SCI11ENDIAN_UINT16(base + i * 2));
 		} else {
-			scr->freeScript();
+			// In SCI0 early, locals are set at run time, thus zero them all here
+			for (uint16 i = 0; i < getLocalsCount(); i++)
+				locals->_locals[i] = NULL_REG;
 		}
-	} else {
-		scr = segMan->allocateScript(scriptNum, &segmentId);
 	}
+}
 
-	scr->init(scriptNum, resMan);
-	scr->load(resMan);
-
+void Script::initialiseClasses(SegManager *segMan) {
+	const byte *seeker = 0;
+	uint16 mult = 0;
+	
 	if (getSciVersion() >= SCI_VERSION_1_1) {
-		int heapStart = scr->getScriptSize();
-		segMan->scriptInitialiseLocals(make_reg(segmentId, heapStart + 4));
-		segMan->scriptInitialiseObjectsSci11(segmentId);
-		scr->relocate(make_reg(segmentId, READ_SCI11ENDIAN_UINT16(scr->_heapStart)));
+		seeker = _heapStart + 4 + READ_SCI11ENDIAN_UINT16(_heapStart + 2) * 2;
+		mult = 2;
 	} else {
-		script_instantiate_sci0(scr, segmentId, segMan);
-		byte *relocationBlock = scr->findBlock(SCI_OBJ_POINTERS);
-		if (relocationBlock)
-			scr->relocate(make_reg(segmentId, relocationBlock - scr->_buf + 4));
+		seeker = findBlock(SCI_OBJ_CLASS);
+		mult = 1;
 	}
 
-	return segmentId;
-}
-
-void script_uninstantiate_sci0(SegManager *segMan, int script_nr, SegmentId seg) {
-	bool oldScriptHeader = (getSciVersion() == SCI_VERSION_0_EARLY);
-	reg_t reg = make_reg(seg, oldScriptHeader ? 2 : 0);
-	int objType, objLength = 0;
-	Script *scr = segMan->getScript(seg);
+	if (!seeker)
+		return;
 
-	// Make a pass over the object in order uninstantiate all superclasses
+	uint16 marker;
+	bool isClass;
+	uint16 classpos;
+	int16 species = 0;
 
-	do {
-		reg.offset += objLength; // Step over the last checked object
+	while (true) {
+		// In SCI0-SCI1, this is the segment type. In SCI11, it's a marker (0x1234)
+		marker = READ_SCI11ENDIAN_UINT16(seeker);
+		classpos = seeker - _buf;
 
-		objType = scr->getHeap(reg.offset);
-		if (!objType)
+		if (!marker)
 			break;
-		objLength = scr->getHeap(reg.offset + 2);  // use SEG_UGET_HEAP ??
 
-		reg.offset += 4; // Step over header
+		if (getSciVersion() >= SCI_VERSION_1_1) {
+			isClass = (READ_SCI11ENDIAN_UINT16(seeker + 14) & kInfoFlagClass);	// -info- selector
+			species = READ_SCI11ENDIAN_UINT16(seeker + 10);
+		} else {
+			isClass = (marker == SCI_OBJ_CLASS);
+			if (isClass)
+				species = READ_SCI11ENDIAN_UINT16(seeker + 12);
+			classpos += 12;
+		}
 
-		if ((objType == SCI_OBJ_OBJECT) || (objType == SCI_OBJ_CLASS)) { // object or class?
-			int superclass;
+		if (isClass) {
+			// WORKAROUNDs for off-by-one script errors
+			if (g_sci->getGameId() == GID_LSL2 && g_sci->isDemo() && species == (int)segMan->classTableSize())
+				segMan->resizeClassTable(segMan->classTableSize() + 1);
+			if (g_sci->getGameId() == GID_LSL3 && !g_sci->isDemo() && _nr == 500 && species == (int)segMan->classTableSize())
+				segMan->resizeClassTable(segMan->classTableSize() + 1);
+			if (g_sci->getGameId() == GID_SQ3 && !g_sci->isDemo() && _nr == 93 && species == (int)segMan->classTableSize())
+				segMan->resizeClassTable(segMan->classTableSize() + 1);
+			if (g_sci->getGameId() == GID_SQ3 && !g_sci->isDemo() && _nr == 99 && species == (int)segMan->classTableSize())
+				segMan->resizeClassTable(segMan->classTableSize() + 1);
+
+			if (species < 0 || species >= (int)segMan->classTableSize())
+				error("Invalid species %d(0x%x) unknown max %d(0x%x) while instantiating script %d\n",
+						  species, species, segMan->classTableSize(), segMan->classTableSize(), _nr);
+
+			SegmentId segmentId = segMan->getScriptSegment(_nr);
+			segMan->setClassOffset(species, make_reg(segmentId, classpos));
+		}
 
-			reg.offset -= SCRIPT_OBJECT_MAGIC_OFFSET;
+		seeker += READ_SCI11ENDIAN_UINT16(seeker + 2) * mult;
+	}
+}
 
-			superclass = scr->getHeap(reg.offset + SCRIPT_SUPERCLASS_OFFSET); // Get superclass...
+void Script::initialiseObjectsSci0(SegManager *segMan, SegmentId segmentId) {
+	bool oldScriptHeader = (getSciVersion() == SCI_VERSION_0_EARLY);
+	const byte *seeker = _buf + (oldScriptHeader ? 2 : 0);
 
-			if (superclass >= 0) {
-				int superclass_script = segMan->getClass(superclass).script;
+	do {
+		uint16 objType = READ_SCI11ENDIAN_UINT16(seeker);
+		if (!objType)
+			break;
 
-				if (superclass_script == script_nr) {
-					if (scr->getLockers())
-						scr->decrementLockers();  // Decrease lockers if this is us ourselves
-				} else
-					script_uninstantiate(segMan, superclass_script);
-				// Recurse to assure that the superclass lockers number gets decreased
+		switch (objType) {
+		case SCI_OBJ_OBJECT:
+		case SCI_OBJ_CLASS:
+			{
+				reg_t addr = make_reg(segmentId, seeker - _buf + 4);
+				Object *obj = scriptObjInit(addr);
+				obj->initSpecies(segMan, addr);
+
+				if (!obj->initBaseObject(segMan, addr)) {
+					if (_nr == 202 && g_sci->getGameId() == GID_KQ5) {
+						// WORKAROUND: Script 202 of KQ5 French and German 
+						// (perhaps Spanish too?) has an invalid object.
+						// This is non-fatal. Refer to bug #3035396.
+					} else {
+						error("Failed to locate base object for object at %04X:%04X; skipping", PRINT_REG(addr));
+					}
+					scriptObjRemove(addr);
+				}
 			}
+			break;
 
-			reg.offset += SCRIPT_OBJECT_MAGIC_OFFSET;
-		} // if object or class
+		default:
+			break;
+		}
 
-		reg.offset -= 4; // Step back on header
+		seeker += READ_SCI11ENDIAN_UINT16(seeker + 2);
+	} while ((uint32)(seeker - _buf) < getScriptSize() - 2);
 
-	} while (objType != 0);
+	byte *relocationBlock = findBlock(SCI_OBJ_POINTERS);
+	if (relocationBlock)
+		relocate(make_reg(segmentId, relocationBlock - getBuf() + 4));
 }
 
-void script_uninstantiate(SegManager *segMan, int script_nr) {
-	SegmentId segment = segMan->getScriptSegment(script_nr);
-	Script *scr = segMan->getScriptIfLoaded(segment);
+void Script::initialiseObjectsSci11(SegManager *segMan, SegmentId segmentId) {
+	const byte *seeker = _heapStart + 4 + READ_SCI11ENDIAN_UINT16(_heapStart + 2) * 2;
 
-	if (!scr) {   // Is it already loaded?
-		//warning("unloading script 0x%x requested although not loaded", script_nr);
-		// This is perfectly valid SCI behaviour
-		return;
-	}
+	while (READ_SCI11ENDIAN_UINT16(seeker) == SCRIPT_OBJECT_MAGIC_NUMBER) {
+		reg_t reg = make_reg(segmentId, seeker - _buf);
+		Object *obj = scriptObjInit(reg);
 
-	scr->decrementLockers();   // One less locker
+		// Copy base from species class, as we need its selector IDs
+		obj->setSuperClassSelector(
+			segMan->getClassAddress(obj->getSuperClassSelector().offset, SCRIPT_GET_LOCK, NULL_REG));
 
-	if (scr->getLockers() > 0)
-		return;
+		// If object is instance, get -propDict- from class and set it for this
+		// object. This is needed for ::isMemberOf() to work.
+		// Example testcase - room 381 of sq4cd - if isMemberOf() doesn't work,
+		// talk-clicks on the robot will act like clicking on ego
+		if (!obj->isClass()) {
+			reg_t classObject = obj->getSuperClassSelector();
+			const Object *classObj = segMan->getObject(classObject);
+			obj->setPropDictSelector(classObj->getPropDictSelector());
+		}
 
-	// Free all classtable references to this script
-	for (uint i = 0; i < segMan->classTableSize(); i++)
-		if (segMan->getClass(i).reg.segment == segment)
-			segMan->setClassOffset(i, NULL_REG);
+		// Set the -classScript- selector to the script number.
+		// FIXME: As this selector is filled in at run-time, it is likely
+		// that it is supposed to hold a pointer. The Obj::isKindOf method
+		// uses this selector together with -propDict- to compare classes.
+		// For the purpose of Obj::isKindOf, using the script number appears
+		// to be sufficient.
+		obj->setClassScriptSelector(make_reg(0, _nr));
 
-	if (getSciVersion() < SCI_VERSION_1_1)
-		script_uninstantiate_sci0(segMan, script_nr, segment);
-	// FIXME: Add proper script uninstantiation for SCI 1.1
+		seeker += READ_SCI11ENDIAN_UINT16(seeker + 2) * 2;
+	}
 
-	if (scr->getLockers())
-		return; // if xxx.lockers > 0
+	relocate(make_reg(segmentId, READ_SCI11ENDIAN_UINT16(_heapStart)));
+}
+
+reg_t Script::findCanonicAddress(SegManager *segMan, reg_t addr) const {
+	addr.offset = 0;
+	return addr;
+}
 
-	// Otherwise unload it completely
-	// Explanation: I'm starting to believe that this work is done by SCI itself.
-	scr->markDeleted();
+void Script::freeAtAddress(SegManager *segMan, reg_t addr) {
+	/*
+		debugC(2, kDebugLevelGC, "[GC] Freeing script %04x:%04x", PRINT_REG(addr));
+		if (_localsSegment)
+			debugC(2, kDebugLevelGC, "[GC] Freeing locals %04x:0000", _localsSegment);
+	*/
+
+	if (_markedAsDeleted)
+		segMan->deallocateScript(_nr);
+}
 
-	debugC(kDebugLevelScripts, "Unloaded script 0x%x.", script_nr);
+Common::Array<reg_t> Script::listAllDeallocatable(SegmentId segId) const {
+	const reg_t r = make_reg(segId, 0);
+	return Common::Array<reg_t>(&r, 1);
+}
 
-	return;
+Common::Array<reg_t> Script::listAllOutgoingReferences(reg_t addr) const {
+	Common::Array<reg_t> tmp;
+	if (addr.offset <= _bufSize && addr.offset >= -SCRIPT_OBJECT_MAGIC_OFFSET && RAW_IS_OBJECT(_buf + addr.offset)) {
+		const Object *obj = getObject(addr.offset);
+		if (obj) {
+			// Note all local variables, if we have a local variable environment
+			if (_localsSegment)
+				tmp.push_back(make_reg(_localsSegment, 0));
+
+			for (uint i = 0; i < obj->getVarCount(); i++)
+				tmp.push_back(obj->getVariable(i));
+		} else {
+			error("Request for outgoing script-object reference at %04x:%04x failed", PRINT_REG(addr));
+		}
+	} else {
+		/*		warning("Unexpected request for outgoing script-object references at %04x:%04x", PRINT_REG(addr));*/
+		/* Happens e.g. when we're looking into strings */
+	}
+	return tmp;
 }
 
+Common::Array<reg_t> Script::listObjectReferences() const {
+	Common::Array<reg_t> tmp;
+
+	// Locals, if present
+	if (_localsSegment)
+		tmp.push_back(make_reg(_localsSegment, 0));
+
+	// All objects (may be classes, may be indirectly reachable)
+	ObjMap::iterator it;
+	const ObjMap::iterator end = _objects.end();
+	for (it = _objects.begin(); it != end; ++it) {
+		tmp.push_back(it->_value.getPos());
+	}
+
+	return tmp;
+}
 
 } // End of namespace Sci