Files
2026-02-02 04:50:13 +01:00

722 lines
17 KiB
C++

#include "cvcrfile.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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#include "lastexpress/lastexpress.h"
#include "common/file.h"
#include "common/memstream.h"
#include "common/savefile.h"
#include "common/stream.h"
#include "engines/metaengine.h"
namespace LastExpress {
CVCRFile::CVCRFile(LastExpressEngine *engine) {
_engine = engine;
_filename = "";
_virtualFileIsOpen = false;
_virtualFileSize = 0;
_rwStreamSize = 0;
memset(_rleDstBuf, 0, sizeof(_rleDstBuf));
_rleBufferPosition = -1;
_rleByte = 0;
_rleCount = 0;
_rleMode = 0;
_bytesProcessed = 0;
_rleStatus = 0;
_fileMode = 0;
}
CVCRFile::~CVCRFile() {
close();
}
bool CVCRFile::open(const char *filename, int mode) {
_filename = filename;
_rleBufferPosition = -1;
switch (mode) {
case CVCRMODE_WB:
debug(6, "CVCRFile::open(): Opening file \'%s\' on mode 0 (\'wb\')", filename);
break;
case CVCRMODE_RB:
debug(6, "CVCRFile::open(): Opening file \'%s\' on mode 0 (\'rb\')", filename);
break;
case CVCRMODE_RWB:
debug(6, "CVCRFile::open(): Opening file \'%s\' on mode 0 (\'r+b\')", filename);
break;
default:
error("CVCRFile::open(): Invalid file mode");
}
Common::OutSaveFile *outSaveFile = nullptr;
Common::InSaveFile *inSaveFile = nullptr;
if (mode == CVCRMODE_WB) {
outSaveFile = g_engine->getSaveFileManager()->openForSaving(_engine->getTargetName() + "-" + Common::String(_filename), false);
_virtualFileIsOpen = outSaveFile != nullptr;
if (outSaveFile)
_virtualFileSize = (uint32)outSaveFile->size();
} else {
inSaveFile = g_engine->getSaveFileManager()->openForLoading(_engine->getTargetName() + "-" + Common::String(_filename));
_virtualFileIsOpen = inSaveFile != nullptr;
if (inSaveFile)
_virtualFileSize = (uint32)inSaveFile->size();
}
_fileMode = mode;
if (!_virtualFileIsOpen) {
error("Error opening file \"%s\". It probably doesn\'t exist or is write protected.", _filename.c_str());
} else {
// If this file was opened on 'r+b' mode, allocate at least 16kb
uint32 fileSize = ((_fileMode == CVCRMODE_RWB || _fileMode == CVCRMODE_WB) && _virtualFileSize < 16 * 1024) ? 16 * 1024 : _virtualFileSize;
if (inSaveFile && fileSize) {
byte *fileContent = (byte *)malloc(fileSize);
if (!fileContent) {
error("Out of memory");
}
inSaveFile->read(fileContent, fileSize);
_rwStream = new Common::MemorySeekableReadWriteStream(fileContent, fileSize, DisposeAfterUse::YES);
_rwStreamSize = fileSize;
delete inSaveFile;
}
if (outSaveFile && fileSize) {
byte *fileContent = (byte *)malloc(fileSize);
if (!fileContent) {
error("Out of memory");
}
memset(fileContent, 0, fileSize);
_rwStream = new Common::MemorySeekableReadWriteStream(fileContent, fileSize, DisposeAfterUse::YES);
_rwStreamSize = fileSize;
outSaveFile->finalize();
delete outSaveFile;
}
}
return _virtualFileIsOpen;
}
uint32 CVCRFile::read(void *dstBuf, uint32 elementSize, uint32 elementCount, bool forceSimpleReadOnRle, bool checkSize) {
uint32 readAmount;
if ((forceSimpleReadOnRle || !_rleStatus) && _virtualFileIsOpen) {
readAmount = _rwStream->read(dstBuf, elementSize * elementCount);
if (checkSize) {
if (readAmount != elementSize * elementCount) {
error("Error reading from file \"%s\"", _filename.c_str());
}
}
return readAmount / elementSize;
} else {
error("Error reading from file \"%s\"", _filename.c_str());
return 0;
}
}
uint32 CVCRFile::write(void *srcBuf, uint32 elementSize, uint32 elementCount, bool forceSimpleWriteOnRle) {
uint32 wroteAmount;
if ((forceSimpleWriteOnRle || !_rleStatus) && _virtualFileIsOpen) {
// Check if we have to allocate a bigger stream...
uint32 amountToWrite = elementSize * elementCount;
int64 atWhichPos = _rwStream->pos();
uint32 oldSize = _rwStreamSize;
bool haveToRaiseStreamSize = amountToWrite + atWhichPos > _rwStreamSize;
if (haveToRaiseStreamSize) {
while (amountToWrite + atWhichPos > _rwStreamSize) {
_rwStreamSize += 16 * 1024; // Add another 16 kb until we can fit the new data...
}
// Allocate the new and bigger buffer and create a new stream with it...
byte *newBuffer = (byte *)malloc(_rwStreamSize);
if (!newBuffer) {
error("Out of memory");
}
Common::MemorySeekableReadWriteStream *newStream = new Common::MemorySeekableReadWriteStream(newBuffer, _rwStreamSize, DisposeAfterUse::YES);
// Create a temporary buffer in which we will pour the old data...
byte *tmp = (byte *)malloc(oldSize);
if (!tmp) {
error("Out of memory");
}
// Read the old data from the old stream to the temporary buffer...
_rwStream->seek(0, SEEK_SET);
_rwStream->read(tmp, oldSize);
// Delete the old stream...
_rwStream->finalize();
delete _rwStream;
// Update the pointer for _rwStream with the new one...
_rwStream = newStream;
_rwStream->write(tmp, oldSize);
_rwStream->seek(atWhichPos, SEEK_SET);
// Clean-up...
free(tmp);
}
wroteAmount = _rwStream->write(srcBuf, amountToWrite);
if (wroteAmount != amountToWrite) {
error("Error writing to file \"%s\". Your disk is probably full.", _filename.c_str());
}
// Update virtual file size...
_virtualFileSize = _virtualFileSize < (amountToWrite + atWhichPos) ? (amountToWrite + atWhichPos) : _virtualFileSize;
return wroteAmount / elementSize;
} else {
error("Error writing to file \"%s\". Your disk is probably full.", _filename.c_str());
return 0;
}
}
uint32 CVCRFile::readRLE(void *dstBuf, uint32 elementSize, uint32 elementCount) {
uint8 curRleOp;
uint8 *value = (uint8 *)dstBuf;
uint32 remaining = elementSize * elementCount;
if (_rleStatus == 2) {
error("Error reading from file \"%s\"", _filename.c_str());
return 0;
}
_rleStatus = 1;
if (remaining != 0) {
while (true) {
if (_rleMode >= 2) {
if (_rleMode == 2) {
*value = _rleByte;
value++;
_rleCount--;
if (!_rleCount)
_rleMode = 1;
}
if (!--remaining)
return elementCount;
continue;
}
if (_rleBufferPosition == -1 || _rleBufferPosition >= 256) {
read(_rleDstBuf, 1, 256, true, false);
_rleBufferPosition = 0;
}
curRleOp = _rleDstBuf[_rleBufferPosition];
_rleBufferPosition++;
switch (curRleOp) {
case 0xFE:
if (_rleBufferPosition == -1 || _rleBufferPosition >= 256) {
read(_rleDstBuf, 1, 256, true, false);
_rleBufferPosition = 0;
}
curRleOp = _rleDstBuf[_rleBufferPosition];
_rleBufferPosition++;
*value = curRleOp;
value++;
break;
case 0xFF:
if (_rleBufferPosition == -1 || _rleBufferPosition >= 256) {
read(_rleDstBuf, 1, 256, true, false);
_rleBufferPosition = 0;
}
_rleCount = _rleDstBuf[_rleBufferPosition] - 1;
_rleBufferPosition++;
if (_rleBufferPosition == -1 || _rleBufferPosition >= 256) {
read(_rleDstBuf, 1, 256, true, false);
_rleBufferPosition = 0;
}
_rleByte = _rleDstBuf[_rleBufferPosition];
_rleBufferPosition++;
*value = _rleByte;
value++;
_rleMode = 2;
break;
case 0xFB:
_rleCount = 2;
_rleByte = 0;
*value = 0;
value++;
_rleMode = 2;
break;
case 0xFD:
if (_rleBufferPosition == -1 || _rleBufferPosition >= 256) {
read(_rleDstBuf, 1, 256, 1, 0);
_rleBufferPosition = 0;
}
_rleByte = 0;
_rleCount = _rleDstBuf[_rleBufferPosition] - 1;
_rleBufferPosition++;
*value = 0;
value++;
_rleMode = 2;
break;
case 0xFC:
_rleCount = 0xFE;
_rleByte = 0;
*value = 0;
value++;
_rleMode = 2;
break;
default:
*value = curRleOp;
value++;
break;
}
if (!--remaining)
return elementCount;
} // while
}
return elementCount;
}
uint32 CVCRFile::writeRLE(void *srcBuf, uint32 elementSize, uint32 elementCount) {
uint8 *value = (uint8 *)srcBuf;
uint32 remaining = elementSize * elementCount;
if (_rleStatus == 1) {
error("Error writing to file \"%s\". Your disk is probably full.", _filename.c_str());
return 0;
}
for (_rleStatus = 2; remaining; --remaining) {
switch (_rleMode) {
case 0:
_rleMode = 1;
_rleByte = *value;
value++;
break;
case 1:
if (*value == _rleByte) {
_rleMode = 2;
_rleCount = 2;
value++;
} else {
if (_rleBufferPosition == -1)
_rleBufferPosition = 0;
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
if (_rleByte < 0xFB) {
_rleDstBuf[_rleBufferPosition] = _rleByte;
} else {
_rleDstBuf[_rleBufferPosition] = 0xFE;
}
_bytesProcessed++;
_rleBufferPosition++;
if (_rleByte >= 0xFB) {
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
_rleDstBuf[_rleBufferPosition] = _rleByte;
_rleBufferPosition++;
_bytesProcessed++;
}
_rleByte = *value;
value++;
}
break;
case 2:
if (*value != _rleByte) {
if (_rleCount != 3 || _rleByte) {
if (_rleCount == 0xFF) {
if (_rleByte) {
writeToRLEBuffer(0xFF, 1);
writeToRLEBuffer(_rleCount, 1);
writeToRLEBuffer(_rleByte, 1);
_rleMode = 1;
_rleByte = *value;
value++;
continue;
}
writeToRLEBuffer(0xFC, 1);
} else {
if (_rleByte) {
writeToRLEBuffer(0xFF, 1);
writeToRLEBuffer(_rleCount, 1);
writeToRLEBuffer(_rleByte, 1);
_rleMode = 1;
_rleByte = *value;
value++;
continue;
}
writeToRLEBuffer(0xFD, 1);
writeToRLEBuffer(_rleCount, 1);
}
} else {
if (_rleBufferPosition == -1)
_rleBufferPosition = 0;
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
_rleDstBuf[_rleBufferPosition++] = 0xFB;
_bytesProcessed++;
}
_rleMode = 1;
_rleByte = *value;
value++;
continue;
}
if (_rleCount == 0xFF) {
if (!_rleByte) {
writeToRLEBuffer(0xFC, 1);
_rleMode = 1;
_rleByte = *value;
value++;
continue;
}
writeToRLEBuffer(0xFF, 1);
writeToRLEBuffer(_rleCount, 1);
writeToRLEBuffer(_rleByte, 1);
_rleMode = 1;
_rleByte = *value;
value++;
continue;
}
value++;
_rleCount++;
break;
default:
break;
}
}
return elementCount;
}
void CVCRFile::writeToRLEBuffer(uint8 operation, uint8 flag) {
if (_rleBufferPosition == -1)
_rleBufferPosition = 0;
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
if (flag || operation < 0xFB) {
_rleDstBuf[_rleBufferPosition] = operation;
} else {
_rleDstBuf[_rleBufferPosition] = 0xFE;
}
_bytesProcessed++;
_rleBufferPosition++;
if (!flag && operation >= 0xFB) {
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
_rleDstBuf[_rleBufferPosition] = operation;
_rleBufferPosition++;
_bytesProcessed++;
}
}
#define FINISH_FLUSH_OP \
{ \
if (_rleBufferPosition != -1 && _rleBufferPosition) { \
write(_rleDstBuf, _rleBufferPosition, 1, true); \
\
_rleBufferPosition = -1; \
_rleStatus = 0; \
_rleMode = 0; \
result = _bytesProcessed; \
_bytesProcessed = 0; \
return result; \
} else { \
_rleStatus = 0; \
_rleMode = 0; \
result = _bytesProcessed; \
_bytesProcessed = 0; \
return result; \
} \
} \
uint32 CVCRFile::flush() {
uint32 result;
if (_rleStatus == 2) {
if (_rleMode == 1) {
if (_rleBufferPosition == -1)
_rleBufferPosition = 0;
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, 1);
}
if (_rleByte < 0xFB) {
_rleDstBuf[_rleBufferPosition] = _rleByte;
} else {
_rleDstBuf[_rleBufferPosition] = 0xFE;
}
_rleBufferPosition++;
_bytesProcessed++;
if (_rleByte >= 0xFB) {
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
_rleDstBuf[_rleBufferPosition] = _rleByte;
_rleBufferPosition++;
_bytesProcessed++;
}
FINISH_FLUSH_OP;
}
if (_rleMode != 2) {
FINISH_FLUSH_OP;
}
if (_rleCount == 3 && !_rleByte) {
if (_rleBufferPosition == -1)
_rleBufferPosition = 0;
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
_rleDstBuf[_rleBufferPosition] = 0xFB;
_rleBufferPosition++;
_bytesProcessed++;
FINISH_FLUSH_OP;
}
if (_rleCount == 0xFF) {
if (!_rleByte) {
if (_rleBufferPosition == -1)
_rleBufferPosition = 0;
if (_rleBufferPosition == 256) {
_rleBufferPosition = 0;
write(_rleDstBuf, 256, 1, true);
}
_rleDstBuf[_rleBufferPosition] = 0xFC;
_rleBufferPosition++;
_bytesProcessed++;
FINISH_FLUSH_OP;
}
} else if (!_rleByte) {
writeToRLEBuffer(0xFD, 1);
writeToRLEBuffer(_rleCount, 1);
FINISH_FLUSH_OP;
}
writeToRLEBuffer(0xFF, 1);
writeToRLEBuffer(_rleCount, 1);
writeToRLEBuffer(_rleByte, 1);
FINISH_FLUSH_OP;
}
if (_rleStatus == 1) {
_rleStatus = 0;
if (_rleBufferPosition != -1 && _rleBufferPosition != 256) {
seek(_rleBufferPosition - 256, SEEK_CUR);
_rleBufferPosition = -1;
_rleStatus = 0;
_rleMode = 0;
result = _bytesProcessed;
_bytesProcessed = 0;
return result;
}
}
_rleStatus = 0;
_rleMode = 0;
result = _bytesProcessed;
_bytesProcessed = 0;
return result;
}
#undef FINISH_FLUSH_OP
uint32 CVCRFile::seek(int32 offset, int mode) {
int result;
if (_rleStatus) {
error("Error seeking in file \"%s\"", _filename.c_str());
return 0;
} else {
if (_virtualFileIsOpen) {
result = !_rwStream->seek(offset, mode);
if (result) {
error("Error seeking in file \"%s\"", _filename.c_str());
}
return result;
} else {
error("Error seeking in file \"%s\"", _filename.c_str());
return 0;
}
}
}
void CVCRFile::close() {
if (_virtualFileIsOpen) {
Common::OutSaveFile *dumpFile = _engine->getSaveFileManager()->openForSaving(_engine->getTargetName() + "-" + Common::String(_filename), false);
bool dumpFileIsOpen = dumpFile != nullptr;
if (!dumpFileIsOpen) {
error("Error opening file \"%s\". It probably doesn\'t exist or is write protected.", _filename.c_str());
}
_rwStream->seek(0, SEEK_SET);
assert(_virtualFileSize <= _rwStream->size());
byte *dumpFileBuf = (byte *)malloc(_virtualFileSize);
if (!dumpFileBuf) {
error("Out of memory");
}
_rwStream->read(dumpFileBuf, _virtualFileSize);
dumpFile->write(dumpFileBuf, _virtualFileSize);
if (!dumpFile->flush()) {
error("Error closing file \"%s\"", _filename.c_str());
}
// This block is not in the original and is used to ensure portability for VCR::shuffleGames()
if (_fileMode == CVCRMODE_WB || _fileMode == CVCRMODE_RWB) {
Common::String tsFilename = _filename;
tsFilename.chop(4);
tsFilename = _engine->getTargetName() + "-" + tsFilename + ".timestamp";
if (_engine->getSaveFileManager()->exists(tsFilename))
_engine->getSaveFileManager()->removeSavefile(tsFilename);
Common::OutSaveFile *tsFile = _engine->getSaveFileManager()->openForSaving(tsFilename, false);
assert(tsFile);
// Add the seconds to the timestamp, so that we have the same granularity as the original...
TimeDate td;
_engine->_system->getTimeAndDate(td, true);
tsFile->writeSint32LE((int32)td.tm_sec);
// Append the extended save header, which includes the file modification timestamp (date and hours/minutes)...
_engine->getMetaEngine()->appendExtendedSave(tsFile, _engine->getTotalPlayTime(), _filename, false);
tsFile->finalize();
delete tsFile;
}
dumpFile->finalize();
delete dumpFile;
free(dumpFileBuf);
_rwStream->finalize();
delete _rwStream;
_rwStream = nullptr;
_rwStreamSize = 0;
_virtualFileSize = 0;
_virtualFileIsOpen = false;
}
}
int32 CVCRFile::tell() {
if (_rleStatus || !_virtualFileIsOpen) {
error("Error telling in file \"%s\"", _filename.c_str());
return 0;
} else {
return (int32)_rwStream->pos();
}
}
} // End of namespace LastExpress