scummvm/engines/scumm/file.cpp
2011-05-12 01:16:22 +02:00

506 lines
11 KiB
C++

/* 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.
*
*/
#include "scumm/file.h"
#include "scumm/scumm.h"
#include "common/memstream.h"
#include "common/substream.h"
namespace Scumm {
#pragma mark -
#pragma mark --- ScummFile ---
#pragma mark -
ScummFile::ScummFile() : _subFileStart(0), _subFileLen(0) {
}
void ScummFile::setSubfileRange(int32 start, int32 len) {
// TODO: Add sanity checks
const int32 fileSize = File::size();
assert(start <= fileSize);
assert(start + len <= fileSize);
_subFileStart = start;
_subFileLen = len;
seek(0, SEEK_SET);
}
void ScummFile::resetSubfile() {
_subFileStart = 0;
_subFileLen = 0;
seek(0, SEEK_SET);
}
bool ScummFile::open(const Common::String &filename) {
if (File::open(filename)) {
resetSubfile();
return true;
} else {
return false;
}
}
bool ScummFile::openSubFile(const Common::String &filename) {
assert(isOpen());
// Disable the XOR encryption and reset any current subfile range
setEnc(0);
resetSubfile();
// Read in the filename table and look for the specified file
unsigned long file_off, file_len;
char file_name[0x20+1];
unsigned long i;
// Get the length of the data file to use for consistency checks
const uint32 data_file_len = size();
// Read offset and length to the file records */
const uint32 file_record_off = readUint32BE();
const uint32 file_record_len = readUint32BE();
// Do a quick check to make sure the offset and length are good
if (file_record_off + file_record_len > data_file_len) {
return false;
}
// Do a little consistancy check on file_record_length
if (file_record_len % 0x28) {
return false;
}
// Scan through the files
for (i = 0; i < file_record_len; i += 0x28) {
// read a file record
seek(file_record_off + i, SEEK_SET);
file_off = readUint32BE();
file_len = readUint32BE();
read(file_name, 0x20);
file_name[0x20] = 0;
assert(file_name[0]);
//debug(7, " extracting \'%s\'", file_name);
// Consistency check. make sure the file data is in the file
if (file_off + file_len > data_file_len) {
return false;
}
if (scumm_stricmp(file_name, filename.c_str()) == 0) {
// We got a match!
setSubfileRange(file_off, file_len);
return true;
}
}
return false;
}
bool ScummFile::eos() const {
return _subFileLen ? _myEos : File::eos();
}
int32 ScummFile::pos() const {
return File::pos() - _subFileStart;
}
int32 ScummFile::size() const {
return _subFileLen ? _subFileLen : File::size();
}
bool ScummFile::seek(int32 offs, int whence) {
if (_subFileLen) {
// Constrain the seek to the subfile
switch (whence) {
case SEEK_END:
offs = _subFileStart + _subFileLen + offs;
break;
case SEEK_SET:
offs += _subFileStart;
break;
case SEEK_CUR:
offs += File::pos();
break;
}
assert((int32)_subFileStart <= offs && offs <= (int32)(_subFileStart + _subFileLen));
whence = SEEK_SET;
}
bool ret = File::seek(offs, whence);
if (ret)
_myEos = false;
return ret;
}
uint32 ScummFile::read(void *dataPtr, uint32 dataSize) {
uint32 realLen;
if (_subFileLen) {
// Limit the amount we read by the subfile boundaries.
const int32 curPos = pos();
assert(_subFileLen >= curPos);
int32 newPos = curPos + dataSize;
if (newPos > _subFileLen) {
dataSize = _subFileLen - curPos;
_myEos = true;
}
}
realLen = File::read(dataPtr, dataSize);
// If an encryption byte was specified, XOR the data we just read by it.
// This simple kind of "encryption" was used by some of the older SCUMM
// games.
if (_encbyte) {
byte *p = (byte *)dataPtr;
byte *end = p + realLen;
while (p < end)
*p++ ^= _encbyte;
}
return realLen;
}
#pragma mark -
#pragma mark --- ScummDiskImage ---
#pragma mark -
static const int maniacResourcesPerFile[55] = {
0, 11, 1, 3, 9, 12, 1, 13, 10, 6,
4, 1, 7, 1, 1, 2, 7, 8, 19, 9,
6, 9, 2, 6, 8, 4, 16, 8, 3, 3,
12, 12, 2, 8, 1, 1, 2, 1, 9, 1,
3, 7, 3, 3, 13, 5, 4, 3, 1, 1,
3, 10, 1, 0, 0
};
static const int zakResourcesPerFile[59] = {
0, 29, 12, 14, 13, 4, 4, 10, 7, 4,
14, 19, 5, 4, 7, 6, 11, 9, 4, 4,
1, 3, 3, 5, 1, 9, 4, 10, 13, 6,
7, 10, 2, 6, 1, 11, 2, 5, 7, 1,
7, 1, 4, 2, 8, 6, 6, 6, 4, 13,
3, 1, 2, 1, 2, 1, 10, 1, 1
};
static uint16 write_byte(Common::WriteStream *out, byte val) {
val ^= 0xFF;
if (out != 0)
out->writeByte(val);
return 1;
}
static uint16 write_word(Common::WriteStream *out, uint16 val) {
val ^= 0xFFFF;
if (out != 0)
out->writeUint16LE(val);
return 2;
}
ScummDiskImage::ScummDiskImage(const char *disk1, const char *disk2, GameSettings game)
: _stream(0), _buf(0), _game(game),
_disk1(disk1), _disk2(disk2), _openedDisk(0) {
if (_game.id == GID_MANIAC) {
_numGlobalObjects = 256;
_numRooms = 55;
_numCostumes = 25;
_numScripts = 160;
_numSounds = 70;
_resourcesPerFile = maniacResourcesPerFile;
} else {
_numGlobalObjects = 775;
_numRooms = 59;
_numCostumes = 38;
_numScripts = 155;
_numSounds = 127;
_resourcesPerFile = zakResourcesPerFile;
}
}
byte ScummDiskImage::fileReadByte() {
byte b = 0;
File::read(&b, 1);
return b;
}
uint16 ScummDiskImage::fileReadUint16LE() {
uint16 a = fileReadByte();
uint16 b = fileReadByte();
return a | (b << 8);
}
bool ScummDiskImage::openDisk(char num) {
if (num == '1')
num = 1;
if (num == '2')
num = 2;
if (_openedDisk != num || !File::isOpen()) {
if (File::isOpen())
File::close();
if (num == 1)
File::open(_disk1);
else if (num == 2)
File::open(_disk2);
else {
error("ScummDiskImage::open(): wrong disk (%c)", num);
return false;
}
_openedDisk = num;
if (!File::isOpen()) {
error("ScummDiskImage::open(): cannot open disk (%d)", num);
return false;
}
}
return true;
}
bool ScummDiskImage::open(const Common::String &filename) {
uint16 signature;
// check signature
openDisk(1);
if (_game.platform == Common::kPlatformApple2GS) {
File::seek(142080);
} else {
File::seek(0);
}
signature = fileReadUint16LE();
if (signature != 0x0A31) {
error("ScummDiskImage::open(): signature not found in disk 1");
return false;
}
extractIndex(0); // Fill in resource arrays
openDisk(2);
if (_game.platform == Common::kPlatformApple2GS) {
File::seek(143104);
signature = fileReadUint16LE();
if (signature != 0x0032)
error("Error: signature not found in disk 2");
} else {
File::seek(0);
signature = fileReadUint16LE();
if (signature != 0x0132)
error("Error: signature not found in disk 2");
}
return true;
}
uint16 ScummDiskImage::extractIndex(Common::WriteStream *out) {
int i;
uint16 reslen = 0;
openDisk(1);
if (_game.platform == Common::kPlatformApple2GS) {
File::seek(142080);
} else {
File::seek(0);
}
// skip signature
fileReadUint16LE();
// write expected signature
if (_game.platform == Common::kPlatformApple2GS) {
reslen += write_word(out, 0x0032);
} else {
reslen += write_word(out, 0x0132);
}
// copy object flags
for (i = 0; i < _numGlobalObjects; i++)
reslen += write_byte(out, fileReadByte());
// copy room offsets
for (i = 0; i < _numRooms; i++) {
_roomDisks[i] = fileReadByte();
reslen += write_byte(out, _roomDisks[i]);
}
for (i = 0; i < _numRooms; i++) {
_roomSectors[i] = fileReadByte();
reslen += write_byte(out, _roomSectors[i]);
_roomTracks[i] = fileReadByte();
reslen += write_byte(out, _roomTracks[i]);
}
for (i = 0; i < _numCostumes; i++)
reslen += write_byte(out, fileReadByte());
for (i = 0; i < _numCostumes; i++)
reslen += write_word(out, fileReadUint16LE());
for (i = 0; i < _numScripts; i++)
reslen += write_byte(out, fileReadByte());
for (i = 0; i < _numScripts; i++)
reslen += write_word(out, fileReadUint16LE());
for (i = 0; i < _numSounds; i++)
reslen += write_byte(out, fileReadByte());
for (i = 0; i < _numSounds; i++)
reslen += write_word(out, fileReadUint16LE());
return reslen;
}
bool ScummDiskImage::generateIndex() {
int bufsize;
bufsize = extractIndex(0);
free(_buf);
_buf = (byte *)calloc(1, bufsize);
Common::MemoryWriteStream out(_buf, bufsize);
extractIndex(&out);
delete _stream;
_stream = new Common::MemoryReadStream(_buf, bufsize);
return true;
}
uint16 ScummDiskImage::extractResource(Common::WriteStream *out, int res) {
const int AppleSectorOffset[36] = {
0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240, 256,
272, 288, 304, 320, 336, 352, 368,
384, 400, 416, 432, 448, 464,
480, 496, 512, 528, 544, 560
};
const int C64SectorOffset[36] = {
0,
0, 21, 42, 63, 84, 105, 126, 147, 168, 189, 210, 231, 252, 273, 294, 315, 336,
357, 376, 395, 414, 433, 452, 471,
490, 508, 526, 544, 562, 580,
598, 615, 632, 649, 666
};
int i;
uint16 reslen = 0;
openDisk(_roomDisks[res]);
if (_game.platform == Common::kPlatformApple2GS) {
File::seek((AppleSectorOffset[_roomTracks[res]] + _roomSectors[res]) * 256);
} else {
File::seek((C64SectorOffset[_roomTracks[res]] + _roomSectors[res]) * 256);
}
for (i = 0; i < _resourcesPerFile[res]; i++) {
uint16 len;
do {
// Note: len might be 0xFFFF for padding in zak-c64-german
len = fileReadUint16LE();
reslen += write_word(out, len);
} while (len == 0xFFFF);
for (len -= 2; len > 0; len--)
reslen += write_byte(out, fileReadByte());
}
return reslen;
}
bool ScummDiskImage::generateResource(int res) {
int bufsize;
if (res >= _numRooms)
return false;
bufsize = extractResource(0, res);
free(_buf);
_buf = (byte *)calloc(1, bufsize);
Common::MemoryWriteStream out(_buf, bufsize);
extractResource(&out, res);
delete _stream;
_stream = new Common::MemoryReadStream(_buf, bufsize);
return true;
}
void ScummDiskImage::close() {
delete _stream;
_stream = 0;
free(_buf);
_buf = 0;
File::close();
}
bool ScummDiskImage::openSubFile(const Common::String &filename) {
assert(isOpen());
const char *ext = strrchr(filename.c_str(), '.');
char resNum[3];
int res;
// We always have file name in form of XX.lfl
resNum[0] = ext[-2];
resNum[1] = ext[-1];
resNum[2] = 0;
res = atoi(resNum);
if (res == 0) {
return generateIndex();
} else {
return generateResource(res);
}
return true;
}
uint32 ScummDiskImage::read(void *dataPtr, uint32 dataSize) {
uint32 realLen = _stream->read(dataPtr, dataSize);
if (_encbyte) {
byte *p = (byte *)dataPtr;
byte *end = p + realLen;
while (p < end)
*p++ ^= _encbyte;
}
return realLen;
}
} // End of namespace Scumm