scummvm/engines/kyra/script.cpp

567 lines
12 KiB
C++

/* ScummVM - Scumm Interpreter
* Copyright (C) 2004-2006 The ScummVM project
*
* 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.
*
* $URL$
* $Id$
*
*/
#include "common/stdafx.h"
#include "common/endian.h"
#include "common/stream.h"
#include "common/util.h"
#include "common/system.h"
#include "kyra/kyra.h"
#include "kyra/resource.h"
#include "kyra/script.h"
#define FORM_CHUNK 0x4D524F46
#define TEXT_CHUNK 0x54584554
#define DATA_CHUNK 0x41544144
#define ORDR_CHUNK 0x5244524F
namespace Kyra {
ScriptHelper::ScriptHelper(KyraEngine *vm) : _vm(vm) {
#define COMMAND(x) { &ScriptHelper::x, #x }
// now we create a list of all Command/Opcode procs and so
static CommandEntry commandProcs[] = {
// 0x00
COMMAND(c1_jmpTo),
COMMAND(c1_setRetValue),
COMMAND(c1_pushRetOrPos),
COMMAND(c1_push),
// 0x04
COMMAND(c1_push),
COMMAND(c1_pushVar),
COMMAND(c1_pushBPNeg),
COMMAND(c1_pushBPAdd),
// 0x08
COMMAND(c1_popRetOrPos),
COMMAND(c1_popVar),
COMMAND(c1_popBPNeg),
COMMAND(c1_popBPAdd),
// 0x0C
COMMAND(c1_addSP),
COMMAND(c1_subSP),
COMMAND(c1_execOpcode),
COMMAND(c1_ifNotJmp),
// 0x10
COMMAND(c1_negate),
COMMAND(c1_eval),
COMMAND(c1_setRetAndJmp)
};
_commands = commandProcs;
#undef COMMAND
}
ScriptHelper::~ScriptHelper() {
}
bool ScriptHelper::loadScript(const char *filename, ScriptData *scriptData, KyraEngine::OpcodeProc *opcodes, int opcodeSize, byte *specialPtr) {
uint32 size = 0;
uint8 *data = _vm->resource()->fileData(filename, &size);
byte *curData = data;
uint32 formBlockSize = getFORMBlockSize(curData);
if (formBlockSize == (uint32)-1) {
delete [] data;
error("No FORM chunk found in file: '%s'", filename);
return false;
}
uint32 chunkSize = getIFFBlockSize(data, curData, size, TEXT_CHUNK);
if (chunkSize != (uint32)-1) {
if (specialPtr) {
scriptData->mustBeFreed = 0;
scriptData->text = specialPtr;
specialPtr += chunkSize;
} else {
scriptData->mustBeFreed = 1;
scriptData->text = new byte[chunkSize];
}
if (!loadIFFBlock(data, curData, size, TEXT_CHUNK, scriptData->text, chunkSize)) {
delete [] data;
unloadScript(scriptData);
error("Couldn't load TEXT chunk from file: '%s'", filename);
return false;
}
}
chunkSize = getIFFBlockSize(data, curData, size, ORDR_CHUNK);
if (chunkSize == (uint32)-1) {
delete [] data;
unloadScript(scriptData);
error("No ORDR chunk found in file: '%s'", filename);
return false;
}
if (specialPtr) {
scriptData->mustBeFreed = 0;
scriptData->ordr = specialPtr;
specialPtr += chunkSize;
} else {
scriptData->mustBeFreed = 1;
scriptData->ordr = new byte[chunkSize];
}
if (!loadIFFBlock(data, curData, size, ORDR_CHUNK, scriptData->ordr, chunkSize)) {
delete [] data;
unloadScript(scriptData);
error("Couldn't load ORDR chunk from file: '%s'", filename);
return false;
}
chunkSize = chunkSize / 2;
while (chunkSize--) {
((uint16*)scriptData->ordr)[chunkSize] = READ_BE_UINT16(&((uint16*)scriptData->ordr)[chunkSize]);
}
chunkSize = getIFFBlockSize(data, curData, size, DATA_CHUNK);
if (chunkSize == (uint32)-1) {
delete [] data;
unloadScript(scriptData);
error("No DATA chunk found in file: '%s'", filename);
return false;
}
if (specialPtr) {
scriptData->mustBeFreed = 0;
scriptData->data = specialPtr;
specialPtr += chunkSize;
} else {
scriptData->mustBeFreed = 1;
scriptData->data = new byte[chunkSize];
}
if (!loadIFFBlock(data, curData, size, DATA_CHUNK, scriptData->data, chunkSize)) {
delete [] data;
unloadScript(scriptData);
error("Couldn't load DATA chunk from file: '%s'", filename);
return false;
}
scriptData->dataSize = chunkSize / 2;
scriptData->opcodes = opcodes;
scriptData->opcodeSize = opcodeSize;
delete [] data;
return true;
}
void ScriptHelper::unloadScript(ScriptData *data) {
if (data->mustBeFreed) {
delete [] data->text;
delete [] data->ordr;
delete [] data->data;
}
data->mustBeFreed = 0;
data->text = data->ordr = data->data = 0;
}
void ScriptHelper::initScript(ScriptState *scriptStat, ScriptData *data) {
scriptStat->dataPtr = data;
scriptStat->ip = 0;
scriptStat->stack[60] = 0;
scriptStat->bp = 62;
scriptStat->sp = 60;
}
bool ScriptHelper::startScript(ScriptState *script, int function) {
if (!script->dataPtr) {
return false;
}
uint16 functionOffset = ((uint16*)script->dataPtr->ordr)[function];
if (functionOffset == (uint16)-1) {
return false;
}
script->ip = &script->dataPtr->data[functionOffset*2];
return true;
}
bool ScriptHelper::validScript(ScriptState *script) {
if (!script->ip || !script->dataPtr)
return false;
return true;
}
bool ScriptHelper::runScript(ScriptState *script) {
_parameter = 0;
_continue = true;
if (!script->ip) {
return false;
}
int16 code = READ_BE_UINT16(script->ip); script->ip += 2;
int16 opcode = (code >> 8) & 0x1F;
if (code & 0x8000) {
opcode = 0;
_parameter = code & 0x7FFF;
} else if (code & 0x4000) {
_parameter = (int8)(code);
} else if (code & 0x2000) {
_parameter = READ_BE_UINT16(script->ip); script->ip += 2;
} else {
_parameter = 0;
}
if (opcode > 18) {
error("Script unknown command: %d", opcode);
} else {
debugC(5, kDebugLevelScript, "%s([%d/%u])", _commands[opcode].desc, _parameter, (uint)_parameter);
(this->*(_commands[opcode].proc))(script);
}
return _continue;
}
uint32 ScriptHelper::getFORMBlockSize(byte *&data) const {
static const uint32 chunkName = FORM_CHUNK;
if (READ_LE_UINT32(data) != chunkName) {
return (uint32)-1;
}
data += 4;
uint32 retValue = READ_BE_UINT32(data); data += 4;
return retValue;
}
uint32 ScriptHelper::getIFFBlockSize(byte *start, byte *&data, uint32 maxSize, const uint32 chunkName) const {
uint32 size = (uint32)-1;
bool special = false;
if (data == (start + maxSize)) {
data = start + 0x0C;
}
while (data < (start + maxSize)) {
uint32 chunk = READ_LE_UINT32(data); data += 4;
uint32 size_temp = READ_BE_UINT32(data); data += 4;
if (chunk != chunkName) {
if (special) {
data += (size_temp + 1) & 0xFFFFFFFE;
} else {
data = start + 0x0C;
special = true;
}
} else {
// kill our data
data = start;
size = size_temp;
break;
}
}
return size;
}
bool ScriptHelper::loadIFFBlock(byte *start, byte *&data, uint32 maxSize, const uint32 chunkName, byte *loadTo, uint32 ptrSize) const {
bool special = false;
if (data == (start + maxSize)) {
data = start + 0x0C;
}
while (data < (start + maxSize)) {
uint32 chunk = READ_LE_UINT32(data); data += 4;
uint32 chunkSize = READ_BE_UINT32(data); data += 4;
if (chunk != chunkName) {
if (special) {
data += (chunkSize + 1) & 0xFFFFFFFE;
} else {
data = start + 0x0C;
special = true;
}
} else {
uint32 loadSize = 0;
if (chunkSize < ptrSize)
loadSize = chunkSize;
else
loadSize = ptrSize;
memcpy(loadTo, data, loadSize);
chunkSize = (chunkSize + 1) & 0xFFFFFFFE;
if (chunkSize > loadSize) {
data += (chunkSize - loadSize);
}
return true;
}
}
return false;
}
#pragma mark -
#pragma mark - Command implementations
#pragma mark -
void ScriptHelper::c1_jmpTo(ScriptState* script) {
script->ip = script->dataPtr->data + (_parameter << 1);
}
void ScriptHelper::c1_setRetValue(ScriptState* script) {
script->retValue = _parameter;
}
void ScriptHelper::c1_pushRetOrPos(ScriptState* script) {
switch (_parameter) {
case 0:
script->stack[--script->sp] = script->retValue;
break;
case 1:
script->stack[--script->sp] = (script->ip - script->dataPtr->data) / 2 + 1;
script->stack[--script->sp] = script->bp;
script->bp = script->sp + 2;
break;
default:
_continue = false;
script->ip = 0;
break;
}
}
void ScriptHelper::c1_push(ScriptState* script) {
script->stack[--script->sp] = _parameter;
}
void ScriptHelper::c1_pushVar(ScriptState* script) {
script->stack[--script->sp] = script->variables[_parameter];
}
void ScriptHelper::c1_pushBPNeg(ScriptState* script) {
script->stack[--script->sp] = script->stack[(-(int32)(_parameter + 2)) + script->bp];
}
void ScriptHelper::c1_pushBPAdd(ScriptState* script) {
script->stack[--script->sp] = script->stack[(_parameter - 1) + script->bp];
}
void ScriptHelper::c1_popRetOrPos(ScriptState* script) {
switch (_parameter) {
case 0:
script->retValue = script->stack[script->sp++];
break;
case 1:
if (script->sp >= 60) {
_continue = false;
script->ip = 0;
} else {
script->bp = script->stack[script->sp++];
script->ip = script->dataPtr->data + (script->stack[script->sp++] << 1);
}
break;
default:
_continue = false;
script->ip = 0;
break;
}
}
void ScriptHelper::c1_popVar(ScriptState* script) {
script->variables[_parameter] = script->stack[script->sp++];
}
void ScriptHelper::c1_popBPNeg(ScriptState* script) {
script->stack[(-(int32)(_parameter + 2)) + script->bp] = script->stack[script->sp++];
}
void ScriptHelper::c1_popBPAdd(ScriptState* script) {
script->stack[(_parameter - 1) + script->bp] = script->stack[script->sp++];
}
void ScriptHelper::c1_addSP(ScriptState* script) {
script->sp += _parameter;
}
void ScriptHelper::c1_subSP(ScriptState* script) {
script->sp -= _parameter;
}
void ScriptHelper::c1_execOpcode(ScriptState* script) {
assert((uint8)_parameter < script->dataPtr->opcodeSize);
if (script->dataPtr->opcodes[(uint8)_parameter] == &KyraEngine::cmd_dummy)
warning("calling unimplemented opcode(0x%.02X)", (uint8)_parameter);
int val = (_vm->*script->dataPtr->opcodes[(uint8)_parameter])(script);
assert(script);
script->retValue = val;
}
void ScriptHelper::c1_ifNotJmp(ScriptState* script) {
if (!script->stack[script->sp++]) {
_parameter &= 0x7FFF;
script->ip = script->dataPtr->data + (_parameter << 1);
}
}
void ScriptHelper::c1_negate(ScriptState* script) {
int16 value = script->stack[script->sp];
switch (_parameter) {
case 0:
if (!value) {
script->stack[script->sp] = 1;
} else {
script->stack[script->sp] = 0;
}
break;
case 1:
script->stack[script->sp] = -value;
break;
case 2:
script->stack[script->sp] = ~value;
break;
default:
_continue = false;
break;
}
}
void ScriptHelper::c1_eval(ScriptState* script) {
int16 ret = 0;
bool error = false;
int16 val1 = script->stack[script->sp++];
int16 val2 = script->stack[script->sp++];
switch (_parameter) {
case 0:
if (!val2 || !val1) {
ret = 0;
} else {
ret = 1;
}
break;
case 1:
if (val2 || val1) {
ret = 1;
} else {
ret = 0;
}
break;
case 2:
if (val1 == val2) {
ret = 1;
} else {
ret = 0;
}
break;
case 3:
if (val1 != val2) {
ret = 1;
} else {
ret = 0;
}
break;
case 4:
if (val1 > val2) {
ret = 1;
} else {
ret = 0;
}
break;
case 5:
if (val1 >= val2) {
ret = 1;
} else {
ret = 0;
}
break;
case 6:
if (val1 < val2) {
ret = 1;
} else {
ret = 0;
}
break;
case 7:
if (val1 <= val2) {
ret = 1;
} else {
ret = 0;
}
break;
case 8:
ret = val1 + val2;
break;
case 9:
ret = val2 - val1;
break;
case 10:
ret = val1 * val2;
break;
case 11:
ret = val2 / val1;
break;
case 12:
ret = val2 >> val1;
break;
case 13:
ret = val2 << val1;
break;
case 14:
ret = val1 & val2;
break;
case 15:
ret = val1 | val2;
break;
case 16:
ret = val2 % val1;
break;
case 17:
ret = val1 ^ val2;
break;
default:
warning("Unknown evaluate func: %d", _parameter);
error = true;
break;
}
if (error) {
script->ip = 0;
_continue = false;
} else {
script->stack[--script->sp] = ret;
}
}
void ScriptHelper::c1_setRetAndJmp(ScriptState* script) {
if (script->sp >= 60) {
_continue = false;
script->ip = 0;
} else {
script->retValue = script->stack[script->sp++];
uint16 temp = script->stack[script->sp++];
script->stack[60] = 0;
script->ip = &script->dataPtr->data[temp*2];
}
}
} // end of namespace Kyra