mirror of
https://github.com/libretro/scummvm.git
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Merged common/gzip-stream.* and common/zlib.*
svn-id: r34578
This commit is contained in:
parent
6a4d96649e
commit
f3dfb5ebab
@ -23,7 +23,7 @@
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*
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*/
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#include "common/gzip-stream.h"
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#include "common/zlib.h"
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#include "backends/saves/compressed/compressed-saves.h"
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@ -1,327 +0,0 @@
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/* ScummVM - Graphic Adventure Engine
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*
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* ScummVM is the legal property of its developers, whose names
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* are too numerous to list here. Please refer to the COPYRIGHT
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* file distributed with this source distribution.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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||||
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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||||
* GNU General Public License for more details.
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||||
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||||
* You should have received a copy of the GNU General Public License
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||||
* along with this program; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*
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* $URL$
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* $Id$
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*
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*/
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#include "common/gzip-stream.h"
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#include "common/util.h"
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#if defined(USE_ZLIB)
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#include <zlib.h>
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#if ZLIB_VERNUM < 0x1204
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#error Version 1.2.0.4 or newer of zlib is required for this code
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#endif
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#endif
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namespace Common {
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#if defined(USE_ZLIB)
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/**
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* A simple wrapper class which can be used to wrap around an arbitrary
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* other SeekableReadStream and will then provide on-the-fly decompression support.
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* Assumes the compressed data to be in gzip format.
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*/
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class GZipReadStream : public Common::SeekableReadStream {
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protected:
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enum {
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BUFSIZE = 16384 // 1 << MAX_WBITS
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};
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byte _buf[BUFSIZE];
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Common::SeekableReadStream *_wrapped;
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z_stream _stream;
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int _zlibErr;
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uint32 _pos;
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uint32 _origSize;
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bool _eos;
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public:
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GZipReadStream(Common::SeekableReadStream *w) : _wrapped(w) {
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assert(w != 0);
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_stream.zalloc = Z_NULL;
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_stream.zfree = Z_NULL;
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_stream.opaque = Z_NULL;
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// Verify file header is correct
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w->seek(0, SEEK_SET);
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uint16 header = w->readUint16BE();
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assert(header == 0x1F8B ||
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((header & 0x0F00) == 0x0800 && header % 31 == 0));
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if (header == 0x1F8B) {
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// Retrieve the original file size
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w->seek(-4, SEEK_END);
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_origSize = w->readUint32LE();
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} else {
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// Original size not available in zlib format
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_origSize = 0;
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}
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_pos = 0;
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w->seek(0, SEEK_SET);
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_eos = false;
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// Adding 32 to windowBits indicates to zlib that it is supposed to
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// automatically detect whether gzip or zlib headers are used for
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// the compressed file. This feature was added in zlib 1.2.0.4,
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// released 10 August 2003.
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// Note: This is *crucial* for savegame compatibility, do *not* remove!
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_zlibErr = inflateInit2(&_stream, MAX_WBITS + 32);
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if (_zlibErr != Z_OK)
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return;
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// Setup input buffer
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_stream.next_in = _buf;
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_stream.avail_in = 0;
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}
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~GZipReadStream() {
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inflateEnd(&_stream);
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delete _wrapped;
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}
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bool err() const { return (_zlibErr != Z_OK) && (_zlibErr != Z_STREAM_END); }
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void clearErr() {
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// only reset _eos; I/O errors are not recoverable
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_eos = false;
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}
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uint32 read(void *dataPtr, uint32 dataSize) {
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_stream.next_out = (byte *)dataPtr;
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_stream.avail_out = dataSize;
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// Keep going while we get no error
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while (_zlibErr == Z_OK && _stream.avail_out) {
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if (_stream.avail_in == 0 && !_wrapped->eos()) {
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// If we are out of input data: Read more data, if available.
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_stream.next_in = _buf;
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_stream.avail_in = _wrapped->read(_buf, BUFSIZE);
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}
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_zlibErr = inflate(&_stream, Z_NO_FLUSH);
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}
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// Update the position counter
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_pos += dataSize - _stream.avail_out;
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if (_zlibErr == Z_STREAM_END && _stream.avail_out > 0)
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_eos = true;
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return dataSize - _stream.avail_out;
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}
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bool eos() const {
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return _eos;
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}
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int32 pos() const {
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return _pos;
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}
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int32 size() const {
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return _origSize;
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}
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bool seek(int32 offset, int whence = SEEK_SET) {
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int32 newPos = 0;
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assert(whence != SEEK_END); // SEEK_END not supported
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switch(whence) {
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case SEEK_SET:
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newPos = offset;
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break;
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case SEEK_CUR:
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newPos = _pos + offset;
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}
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assert(newPos >= 0);
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if ((uint32)newPos < _pos) {
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// To search backward, we have to restart the whole decompression
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// from the start of the file. A rather wasteful operation, best
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// to avoid it. :/
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#if DEBUG
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warning("Backward seeking in GZipReadStream detected");
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#endif
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_pos = 0;
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_wrapped->seek(0, SEEK_SET);
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_zlibErr = inflateReset(&_stream);
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if (_zlibErr != Z_OK)
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return false; // FIXME: STREAM REWRITE
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_stream.next_in = _buf;
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_stream.avail_in = 0;
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}
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offset = newPos - _pos;
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// Skip the given amount of data (very inefficient if one tries to skip
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// huge amounts of data, but usually client code will only skip a few
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// bytes, so this should be fine.
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byte tmpBuf[1024];
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while (!err() && offset > 0) {
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offset -= read(tmpBuf, MIN((int32)sizeof(tmpBuf), offset));
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}
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_eos = false;
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return true; // FIXME: STREAM REWRITE
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}
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};
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/**
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* A simple wrapper class which can be used to wrap around an arbitrary
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* other WriteStream and will then provide on-the-fly compression support.
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* The compressed data is written in the gzip format.
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*/
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class GZipWriteStream : public Common::WriteStream {
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protected:
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enum {
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BUFSIZE = 16384 // 1 << MAX_WBITS
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};
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byte _buf[BUFSIZE];
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Common::WriteStream *_wrapped;
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z_stream _stream;
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int _zlibErr;
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void processData(int flushType) {
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// This function is called by both write() and finalize().
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while (_zlibErr == Z_OK && (_stream.avail_in || flushType == Z_FINISH)) {
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if (_stream.avail_out == 0) {
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if (_wrapped->write(_buf, BUFSIZE) != BUFSIZE) {
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_zlibErr = Z_ERRNO;
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break;
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}
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_stream.next_out = _buf;
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_stream.avail_out = BUFSIZE;
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}
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_zlibErr = deflate(&_stream, flushType);
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}
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}
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public:
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GZipWriteStream(Common::WriteStream *w) : _wrapped(w) {
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assert(w != 0);
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_stream.zalloc = Z_NULL;
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_stream.zfree = Z_NULL;
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_stream.opaque = Z_NULL;
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// Adding 16 to windowBits indicates to zlib that it is supposed to
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// write gzip headers. This feature was added in zlib 1.2.0.4,
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// released 10 August 2003.
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// Note: This is *crucial* for savegame compatibility, do *not* remove!
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_zlibErr = deflateInit2(&_stream,
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Z_DEFAULT_COMPRESSION,
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Z_DEFLATED,
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MAX_WBITS + 16,
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8,
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Z_DEFAULT_STRATEGY);
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assert(_zlibErr == Z_OK);
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_stream.next_out = _buf;
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_stream.avail_out = BUFSIZE;
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_stream.avail_in = 0;
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_stream.next_in = 0;
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}
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~GZipWriteStream() {
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finalize();
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deflateEnd(&_stream);
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delete _wrapped;
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}
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bool err() const {
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// CHECKME: does Z_STREAM_END make sense here?
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return (_zlibErr != Z_OK && _zlibErr != Z_STREAM_END) || _wrapped->err();
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}
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void clearErr() {
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// Note: we don't reset the _zlibErr here, as it is not
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// clear in general how
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_wrapped->clearErr();
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}
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void finalize() {
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if (_zlibErr != Z_OK)
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return;
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// Process whatever remaining data there is.
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processData(Z_FINISH);
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// Since processData only writes out blocks of size BUFSIZE,
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// we may have to flush some stragglers.
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uint remainder = BUFSIZE - _stream.avail_out;
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if (remainder > 0) {
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if (_wrapped->write(_buf, remainder) != remainder) {
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_zlibErr = Z_ERRNO;
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}
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}
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// Finalize the wrapped savefile, too
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_wrapped->finalize();
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}
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uint32 write(const void *dataPtr, uint32 dataSize) {
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if (err())
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return 0;
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// Hook in the new data ...
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// Note: We need to make a const_cast here, as zlib is not aware
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// of the const keyword.
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_stream.next_in = const_cast<byte *>((const byte *)dataPtr);
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_stream.avail_in = dataSize;
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// ... and flush it to disk
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processData(Z_NO_FLUSH);
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return dataSize - _stream.avail_in;
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}
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};
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#endif // USE_ZLIB
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Common::SeekableReadStream *wrapCompressedReadStream(Common::SeekableReadStream *toBeWrapped) {
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#if defined(USE_ZLIB)
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if (toBeWrapped) {
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uint16 header = toBeWrapped->readUint16BE();
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bool isCompressed = (header == 0x1F8B ||
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((header & 0x0F00) == 0x0800 &&
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header % 31 == 0));
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toBeWrapped->seek(-2, SEEK_CUR);
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if (isCompressed)
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return new GZipReadStream(toBeWrapped);
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}
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#endif
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return toBeWrapped;
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}
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Common::WriteStream *wrapCompressedWriteStream(Common::WriteStream *toBeWrapped) {
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#if defined(USE_ZLIB)
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if (toBeWrapped)
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return new GZipWriteStream(toBeWrapped);
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#endif
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return toBeWrapped;
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}
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} // End of namespace Common
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@ -1,58 +0,0 @@
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/* ScummVM - Graphic Adventure Engine
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*
|
||||
* 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.
|
||||
*
|
||||
* $URL$
|
||||
* $Id$
|
||||
*
|
||||
*/
|
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|
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#ifndef COMMON_GZIP_STREAM_H
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#define COMMON_GZIP_STREAM_H
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#include "common/stream.h"
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namespace Common {
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/**
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* Take an arbitrary SeekableReadStream and wrap it in a custom stream which
|
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* provides transparent on-the-fly decompression. Assumes the data it
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* retrieves from the wrapped stream to be either uncompressed or in gzip
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* format. In the former case, the original stream is returned unmodified
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* (and in particular, not wrapped).
|
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*
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* It is safe to call this with a NULL parameter (in this case, NULL is
|
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* returned).
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*/
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Common::SeekableReadStream *wrapCompressedReadStream(Common::SeekableReadStream *toBeWrapped);
|
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/**
|
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* Take an arbitrary WriteStream and wrap it in a custom stream which provides
|
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* transparent on-the-fly compression. The compressed data is written in the
|
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* gzip format, unless ZLIB support has been disabled, in which case the given
|
||||
* stream is returned unmodified (and in particular, not wrapped).
|
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*
|
||||
* It is safe to call this with a NULL parameter (in this case, NULL is
|
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* returned).
|
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*/
|
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Common::WriteStream *wrapCompressedWriteStream(Common::WriteStream *toBeWrapped);
|
||||
|
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} // End of namespace Common
|
||||
|
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#endif
|
@ -7,7 +7,6 @@ MODULE_OBJS := \
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config-manager.o \
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file.o \
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fs.o \
|
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gzip-stream.o \
|
||||
hashmap.o \
|
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memorypool.o \
|
||||
md5.o \
|
||||
|
304
common/zlib.cpp
304
common/zlib.cpp
@ -8,37 +8,327 @@
|
||||
* 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/zlib.h"
|
||||
#include "common/util.h"
|
||||
|
||||
#if defined(USE_ZLIB)
|
||||
#ifdef __SYMBIAN32__
|
||||
#include <zlib\zlib.h>
|
||||
#else
|
||||
#include <zlib.h>
|
||||
#endif
|
||||
|
||||
#ifdef __SYMBIAN32__
|
||||
#include <zlib\zlib.h>
|
||||
#else
|
||||
#include <zlib.h>
|
||||
#if ZLIB_VERNUM < 0x1204
|
||||
#error Version 1.2.0.4 or newer of zlib is required for this code
|
||||
#endif
|
||||
#endif
|
||||
|
||||
|
||||
namespace Common {
|
||||
|
||||
#if defined(USE_ZLIB)
|
||||
|
||||
bool uncompress(byte *dst, unsigned long *dstLen, const byte *src, unsigned long srcLen) {
|
||||
return Z_OK == ::uncompress(dst, dstLen, src, srcLen);
|
||||
}
|
||||
|
||||
} // end of namespace Common
|
||||
/**
|
||||
* A simple wrapper class which can be used to wrap around an arbitrary
|
||||
* other SeekableReadStream and will then provide on-the-fly decompression support.
|
||||
* Assumes the compressed data to be in gzip format.
|
||||
*/
|
||||
class GZipReadStream : public Common::SeekableReadStream {
|
||||
protected:
|
||||
enum {
|
||||
BUFSIZE = 16384 // 1 << MAX_WBITS
|
||||
};
|
||||
|
||||
byte _buf[BUFSIZE];
|
||||
|
||||
Common::SeekableReadStream *_wrapped;
|
||||
z_stream _stream;
|
||||
int _zlibErr;
|
||||
uint32 _pos;
|
||||
uint32 _origSize;
|
||||
bool _eos;
|
||||
|
||||
public:
|
||||
|
||||
GZipReadStream(Common::SeekableReadStream *w) : _wrapped(w) {
|
||||
assert(w != 0);
|
||||
|
||||
_stream.zalloc = Z_NULL;
|
||||
_stream.zfree = Z_NULL;
|
||||
_stream.opaque = Z_NULL;
|
||||
|
||||
// Verify file header is correct
|
||||
w->seek(0, SEEK_SET);
|
||||
uint16 header = w->readUint16BE();
|
||||
assert(header == 0x1F8B ||
|
||||
((header & 0x0F00) == 0x0800 && header % 31 == 0));
|
||||
|
||||
if (header == 0x1F8B) {
|
||||
// Retrieve the original file size
|
||||
w->seek(-4, SEEK_END);
|
||||
_origSize = w->readUint32LE();
|
||||
} else {
|
||||
// Original size not available in zlib format
|
||||
_origSize = 0;
|
||||
}
|
||||
_pos = 0;
|
||||
w->seek(0, SEEK_SET);
|
||||
_eos = false;
|
||||
|
||||
// Adding 32 to windowBits indicates to zlib that it is supposed to
|
||||
// automatically detect whether gzip or zlib headers are used for
|
||||
// the compressed file. This feature was added in zlib 1.2.0.4,
|
||||
// released 10 August 2003.
|
||||
// Note: This is *crucial* for savegame compatibility, do *not* remove!
|
||||
_zlibErr = inflateInit2(&_stream, MAX_WBITS + 32);
|
||||
if (_zlibErr != Z_OK)
|
||||
return;
|
||||
|
||||
// Setup input buffer
|
||||
_stream.next_in = _buf;
|
||||
_stream.avail_in = 0;
|
||||
}
|
||||
|
||||
~GZipReadStream() {
|
||||
inflateEnd(&_stream);
|
||||
delete _wrapped;
|
||||
}
|
||||
|
||||
bool err() const { return (_zlibErr != Z_OK) && (_zlibErr != Z_STREAM_END); }
|
||||
void clearErr() {
|
||||
// only reset _eos; I/O errors are not recoverable
|
||||
_eos = false;
|
||||
}
|
||||
|
||||
uint32 read(void *dataPtr, uint32 dataSize) {
|
||||
_stream.next_out = (byte *)dataPtr;
|
||||
_stream.avail_out = dataSize;
|
||||
|
||||
// Keep going while we get no error
|
||||
while (_zlibErr == Z_OK && _stream.avail_out) {
|
||||
if (_stream.avail_in == 0 && !_wrapped->eos()) {
|
||||
// If we are out of input data: Read more data, if available.
|
||||
_stream.next_in = _buf;
|
||||
_stream.avail_in = _wrapped->read(_buf, BUFSIZE);
|
||||
}
|
||||
_zlibErr = inflate(&_stream, Z_NO_FLUSH);
|
||||
}
|
||||
|
||||
// Update the position counter
|
||||
_pos += dataSize - _stream.avail_out;
|
||||
|
||||
if (_zlibErr == Z_STREAM_END && _stream.avail_out > 0)
|
||||
_eos = true;
|
||||
|
||||
return dataSize - _stream.avail_out;
|
||||
}
|
||||
|
||||
bool eos() const {
|
||||
return _eos;
|
||||
}
|
||||
int32 pos() const {
|
||||
return _pos;
|
||||
}
|
||||
int32 size() const {
|
||||
return _origSize;
|
||||
}
|
||||
bool seek(int32 offset, int whence = SEEK_SET) {
|
||||
int32 newPos = 0;
|
||||
assert(whence != SEEK_END); // SEEK_END not supported
|
||||
switch(whence) {
|
||||
case SEEK_SET:
|
||||
newPos = offset;
|
||||
break;
|
||||
case SEEK_CUR:
|
||||
newPos = _pos + offset;
|
||||
}
|
||||
|
||||
assert(newPos >= 0);
|
||||
|
||||
if ((uint32)newPos < _pos) {
|
||||
// To search backward, we have to restart the whole decompression
|
||||
// from the start of the file. A rather wasteful operation, best
|
||||
// to avoid it. :/
|
||||
#if DEBUG
|
||||
warning("Backward seeking in GZipReadStream detected");
|
||||
#endif
|
||||
_pos = 0;
|
||||
_wrapped->seek(0, SEEK_SET);
|
||||
_zlibErr = inflateReset(&_stream);
|
||||
if (_zlibErr != Z_OK)
|
||||
return false; // FIXME: STREAM REWRITE
|
||||
_stream.next_in = _buf;
|
||||
_stream.avail_in = 0;
|
||||
}
|
||||
|
||||
offset = newPos - _pos;
|
||||
|
||||
// Skip the given amount of data (very inefficient if one tries to skip
|
||||
// huge amounts of data, but usually client code will only skip a few
|
||||
// bytes, so this should be fine.
|
||||
byte tmpBuf[1024];
|
||||
while (!err() && offset > 0) {
|
||||
offset -= read(tmpBuf, MIN((int32)sizeof(tmpBuf), offset));
|
||||
}
|
||||
|
||||
_eos = false;
|
||||
return true; // FIXME: STREAM REWRITE
|
||||
}
|
||||
};
|
||||
|
||||
/**
|
||||
* A simple wrapper class which can be used to wrap around an arbitrary
|
||||
* other WriteStream and will then provide on-the-fly compression support.
|
||||
* The compressed data is written in the gzip format.
|
||||
*/
|
||||
class GZipWriteStream : public Common::WriteStream {
|
||||
protected:
|
||||
enum {
|
||||
BUFSIZE = 16384 // 1 << MAX_WBITS
|
||||
};
|
||||
|
||||
byte _buf[BUFSIZE];
|
||||
Common::WriteStream *_wrapped;
|
||||
z_stream _stream;
|
||||
int _zlibErr;
|
||||
|
||||
void processData(int flushType) {
|
||||
// This function is called by both write() and finalize().
|
||||
while (_zlibErr == Z_OK && (_stream.avail_in || flushType == Z_FINISH)) {
|
||||
if (_stream.avail_out == 0) {
|
||||
if (_wrapped->write(_buf, BUFSIZE) != BUFSIZE) {
|
||||
_zlibErr = Z_ERRNO;
|
||||
break;
|
||||
}
|
||||
_stream.next_out = _buf;
|
||||
_stream.avail_out = BUFSIZE;
|
||||
}
|
||||
_zlibErr = deflate(&_stream, flushType);
|
||||
}
|
||||
}
|
||||
|
||||
public:
|
||||
GZipWriteStream(Common::WriteStream *w) : _wrapped(w) {
|
||||
assert(w != 0);
|
||||
_stream.zalloc = Z_NULL;
|
||||
_stream.zfree = Z_NULL;
|
||||
_stream.opaque = Z_NULL;
|
||||
|
||||
// Adding 16 to windowBits indicates to zlib that it is supposed to
|
||||
// write gzip headers. This feature was added in zlib 1.2.0.4,
|
||||
// released 10 August 2003.
|
||||
// Note: This is *crucial* for savegame compatibility, do *not* remove!
|
||||
_zlibErr = deflateInit2(&_stream,
|
||||
Z_DEFAULT_COMPRESSION,
|
||||
Z_DEFLATED,
|
||||
MAX_WBITS + 16,
|
||||
8,
|
||||
Z_DEFAULT_STRATEGY);
|
||||
assert(_zlibErr == Z_OK);
|
||||
|
||||
_stream.next_out = _buf;
|
||||
_stream.avail_out = BUFSIZE;
|
||||
_stream.avail_in = 0;
|
||||
_stream.next_in = 0;
|
||||
}
|
||||
|
||||
~GZipWriteStream() {
|
||||
finalize();
|
||||
deflateEnd(&_stream);
|
||||
delete _wrapped;
|
||||
}
|
||||
|
||||
bool err() const {
|
||||
// CHECKME: does Z_STREAM_END make sense here?
|
||||
return (_zlibErr != Z_OK && _zlibErr != Z_STREAM_END) || _wrapped->err();
|
||||
}
|
||||
|
||||
void clearErr() {
|
||||
// Note: we don't reset the _zlibErr here, as it is not
|
||||
// clear in general how
|
||||
_wrapped->clearErr();
|
||||
}
|
||||
|
||||
void finalize() {
|
||||
if (_zlibErr != Z_OK)
|
||||
return;
|
||||
|
||||
// Process whatever remaining data there is.
|
||||
processData(Z_FINISH);
|
||||
|
||||
// Since processData only writes out blocks of size BUFSIZE,
|
||||
// we may have to flush some stragglers.
|
||||
uint remainder = BUFSIZE - _stream.avail_out;
|
||||
if (remainder > 0) {
|
||||
if (_wrapped->write(_buf, remainder) != remainder) {
|
||||
_zlibErr = Z_ERRNO;
|
||||
}
|
||||
}
|
||||
|
||||
// Finalize the wrapped savefile, too
|
||||
_wrapped->finalize();
|
||||
}
|
||||
|
||||
uint32 write(const void *dataPtr, uint32 dataSize) {
|
||||
if (err())
|
||||
return 0;
|
||||
|
||||
// Hook in the new data ...
|
||||
// Note: We need to make a const_cast here, as zlib is not aware
|
||||
// of the const keyword.
|
||||
_stream.next_in = const_cast<byte *>((const byte *)dataPtr);
|
||||
_stream.avail_in = dataSize;
|
||||
|
||||
// ... and flush it to disk
|
||||
processData(Z_NO_FLUSH);
|
||||
|
||||
return dataSize - _stream.avail_in;
|
||||
}
|
||||
};
|
||||
|
||||
#endif // USE_ZLIB
|
||||
|
||||
Common::SeekableReadStream *wrapCompressedReadStream(Common::SeekableReadStream *toBeWrapped) {
|
||||
#if defined(USE_ZLIB)
|
||||
if (toBeWrapped) {
|
||||
uint16 header = toBeWrapped->readUint16BE();
|
||||
bool isCompressed = (header == 0x1F8B ||
|
||||
((header & 0x0F00) == 0x0800 &&
|
||||
header % 31 == 0));
|
||||
toBeWrapped->seek(-2, SEEK_CUR);
|
||||
if (isCompressed)
|
||||
return new GZipReadStream(toBeWrapped);
|
||||
}
|
||||
#endif
|
||||
return toBeWrapped;
|
||||
}
|
||||
|
||||
Common::WriteStream *wrapCompressedWriteStream(Common::WriteStream *toBeWrapped) {
|
||||
#if defined(USE_ZLIB)
|
||||
if (toBeWrapped)
|
||||
return new GZipWriteStream(toBeWrapped);
|
||||
#endif
|
||||
return toBeWrapped;
|
||||
}
|
||||
|
||||
|
||||
} // End of namespace Common
|
||||
|
@ -8,29 +8,31 @@
|
||||
* 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 COMMON_ZLIB_H
|
||||
#define COMMON_ZLIB_H
|
||||
|
||||
#include "common/scummsys.h"
|
||||
|
||||
#if defined(USE_ZLIB)
|
||||
#include "common/stream.h"
|
||||
|
||||
namespace Common {
|
||||
|
||||
#if defined(USE_ZLIB)
|
||||
|
||||
/**
|
||||
* Thin wrapper around zlib's uncompress() function. This wrapper makes
|
||||
* it possible to uncompress data in engines without being forced to link
|
||||
@ -40,9 +42,31 @@ namespace Common {
|
||||
*/
|
||||
bool uncompress(byte *dst, unsigned long *dstLen, const byte *src, unsigned long srcLen);
|
||||
|
||||
} // end of namespace Common
|
||||
|
||||
#endif
|
||||
|
||||
#endif
|
||||
/**
|
||||
* Take an arbitrary SeekableReadStream and wrap it in a custom stream which
|
||||
* provides transparent on-the-fly decompression. Assumes the data it
|
||||
* retrieves from the wrapped stream to be either uncompressed or in gzip
|
||||
* format. In the former case, the original stream is returned unmodified
|
||||
* (and in particular, not wrapped).
|
||||
*
|
||||
* It is safe to call this with a NULL parameter (in this case, NULL is
|
||||
* returned).
|
||||
*/
|
||||
Common::SeekableReadStream *wrapCompressedReadStream(Common::SeekableReadStream *toBeWrapped);
|
||||
|
||||
/**
|
||||
* Take an arbitrary WriteStream and wrap it in a custom stream which provides
|
||||
* transparent on-the-fly compression. The compressed data is written in the
|
||||
* gzip format, unless ZLIB support has been disabled, in which case the given
|
||||
* stream is returned unmodified (and in particular, not wrapped).
|
||||
*
|
||||
* It is safe to call this with a NULL parameter (in this case, NULL is
|
||||
* returned).
|
||||
*/
|
||||
Common::WriteStream *wrapCompressedWriteStream(Common::WriteStream *toBeWrapped);
|
||||
|
||||
} // End of namespace Common
|
||||
|
||||
#endif
|
||||
|
Loading…
x
Reference in New Issue
Block a user