Initial commit

engines/cge/fileio.cpp

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+/* 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/>.
+ *
+ */
+
+/*
+ * This code is based on original Soltys source code
+ * Copyright (c) 1994-1995 Janusz B. Wisniewski and L.K. Avalon
+ */
+
+#include "common/system.h"
+#include "common/str.h"
+#include "common/debug.h"
+#include "common/debug-channels.h"
+#include "common/memstream.h"
+#include "cge/cge.h"
+#include "cge/fileio.h"
+
+namespace CGE {
+
+/*-----------------------------------------------------------------------
+ * BtPage
+ *-----------------------------------------------------------------------*/
+void BtPage::readBTree(Common::ReadStream &s) {
+	_header._count = s.readUint16LE();
+	_header._down = s.readUint16LE();
+
+	if (_header._down == kBtValNone) {
+		// Leaf list
+		for (int i = 0; i < kBtLeafCount; ++i) {
+			s.read(_leaf[i]._key, kBtKeySize);
+			_leaf[i]._pos = s.readUint32LE();
+			_leaf[i]._size = s.readUint16LE();
+		}
+	} else {
+		// Root index
+		for (int i = 0; i < kBtInnerCount; ++i) {
+			s.read(_inner[i]._key, kBtKeySize);
+			_inner[i]._down = s.readUint16LE();
+		}
+	}
+}
+
+/*-----------------------------------------------------------------------
+ * ResourceManager
+ *-----------------------------------------------------------------------*/
+ResourceManager::ResourceManager() {
+	debugC(1, kCGEDebugFile, "ResourceManager::ResourceManager()");
+
+	_datFile = new Common::File();
+	_datFile->open(kDatName);
+
+	_catFile = new Common::File();
+	_catFile->open(kCatName);
+
+	if (!_datFile->isOpen() || !_catFile->isOpen())
+		error("Unable to open data files");
+
+	for (int i = 0; i < kBtLevel; i++) {
+		_buff[i]._page = new BtPage;
+		_buff[i]._pageNo = kBtValNone;
+		_buff[i]._index = -1;
+		assert(_buff[i]._page != nullptr);
+	}
+}
+
+ResourceManager::~ResourceManager() {
+	debugC(1, kCGEDebugFile, "ResourceManager::~ResourceManager()");
+	_datFile->close();
+	delete _datFile;
+
+	_catFile->close();
+	delete _catFile;
+
+	for (int i = 0; i < kBtLevel; i++)
+		delete _buff[i]._page;
+}
+
+void ResourceManager::XCrypt(byte *buf, uint16 length) {
+	byte *b = buf;
+
+	for (uint16 i = 0; i < length; i++)
+		*b++ ^= kCryptSeed;
+}
+
+bool ResourceManager::seek(int32 offs, int whence) {
+	return _datFile->seek(offs, whence);
+}
+
+uint16 ResourceManager::read(byte *buf, uint16 length) {
+	if (!_datFile->isOpen())
+		return 0;
+
+	uint16 bytesRead = _datFile->read(buf, length);
+	if (!bytesRead)
+		error("Read %s - %d bytes", _datFile->getName(), length);
+	XCrypt(buf, length);
+	return bytesRead;
+}
+
+BtPage *ResourceManager::getPage(int level, uint16 pageId) {
+	debugC(1, kCGEDebugFile, "ResourceManager::getPage(%d, %d)", level, pageId);
+
+	if (level >= kBtLevel)
+		return nullptr;
+
+	if (_buff[level]._pageNo != pageId) {
+		int32 pos = pageId * kBtSize;
+		_buff[level]._pageNo = pageId;
+
+		if (_catFile->size() <= pos)
+			return nullptr;
+
+		// In the original, there was a check verifying if the
+		// purpose was to write a new file. This should only be
+		// to create a new file, thus it was removed.
+		_catFile->seek(pageId * kBtSize, SEEK_SET);
+
+		// Read in the page
+		byte buffer[kBtSize];
+		int bytesRead = catRead(buffer, kBtSize);
+
+		// Unpack it into the page structure
+		Common::MemoryReadStream stream(buffer, bytesRead, DisposeAfterUse::NO);
+		_buff[level]._page->readBTree(stream);
+		_buff[level]._index = -1;
+	}
+	return _buff[level]._page;
+}
+
+BtKeypack *ResourceManager::find(const char *key) {
+	debugC(1, kCGEDebugFile, "ResourceManager::find(%s)", key);
+
+	int lev = 0;
+	uint16 nxt = kBtValRoot;
+	while (!_catFile->eos()) {
+		BtPage *pg = getPage(lev, nxt);
+		if (!pg)
+			return nullptr;
+
+		// search
+		if (pg->_header._down != kBtValNone) {
+			int i;
+			for (i = 0; i < pg->_header._count; i++) {
+				if (scumm_strnicmp((const char *)key, (const char*)pg->_inner[i]._key, kBtKeySize) < 0)
+					break;
+			}
+			nxt = (i) ? pg->_inner[i - 1]._down : pg->_header._down;
+			_buff[lev]._index = i - 1;
+			lev++;
+		} else {
+			int i;
+			for (i = 0; i < pg->_header._count - 1; i++) {
+				if (scumm_stricmp((const char *)key, (const char *)pg->_leaf[i]._key) <= 0)
+					break;
+			}
+			_buff[lev]._index = i;
+			return &pg->_leaf[i];
+		}
+	}
+	return nullptr;
+}
+
+bool ResourceManager::exist(const char *name) {
+	debugC(1, kCGEDebugFile, "ResourceManager::exist(%s)", name);
+
+	BtKeypack* result = find(name);
+	if (!result)
+		return false;
+
+	return scumm_stricmp(result->_key, name) == 0;
+}
+
+uint16 ResourceManager::catRead(byte *buf, uint16 length) {
+	if (!_catFile->isOpen())
+		return 0;
+
+	uint16 bytesRead = _catFile->read(buf, length);
+	if (!bytesRead)
+		error("Read %s - %d bytes", _catFile->getName(), length);
+	XCrypt(buf, length);
+	return bytesRead;
+}
+
+/*-----------------------------------------------------------------------
+ * EncryptedStream
+ *-----------------------------------------------------------------------*/
+EncryptedStream::EncryptedStream(ResourceManager *resman, const char *name) {
+	debugC(3, kCGEDebugFile, "EncryptedStream::EncryptedStream(%s)", name);
+
+	_error = false;
+	BtKeypack *kp = resman->find(name);
+	if (scumm_stricmp(kp->_key, name) != 0)
+		_error = true;
+
+	resman->seek(kp->_pos);
+	byte *dataBuffer;
+	int bufSize;
+
+	if ((strlen(name) > 4) && (scumm_stricmp(name + strlen(name) - 4, ".SPR") == 0)) {
+		// SPR files have some inconsistencies. Some have extra 0x1A at the end, some others
+		// do not have a carriage return at the end of the last line
+		// Therefore, we remove this ending 0x1A and add extra new lines.
+		// This fixes bug #6060
+		dataBuffer = (byte *)malloc(kp->_size + 2);
+		resman->read(dataBuffer, kp->_size);
+		if (dataBuffer[kp->_size - 1] == 0x1A)
+			dataBuffer[kp->_size - 1] = '\n';
+		dataBuffer[kp->_size] = '\n';
+		dataBuffer[kp->_size + 1] = '\n';
+		bufSize = kp->_size + 2;
+	} else {
+		dataBuffer = (byte *)malloc(kp->_size);
+		resman->read(dataBuffer, kp->_size);
+		bufSize = kp->_size;
+	}
+
+	_readStream = new Common::MemoryReadStream(dataBuffer, bufSize, DisposeAfterUse::YES);
+}
+
+uint32 EncryptedStream::read(byte *dataPtr, uint32 dataSize) {
+	return _readStream->read(dataPtr, dataSize);
+}
+
+bool EncryptedStream::err() {
+	return (_error || _readStream->err());
+}
+
+bool EncryptedStream::eos() {
+	return _readStream->eos();
+}
+
+bool EncryptedStream::seek(int32 offset) {
+	return _readStream->seek(offset);
+}
+
+Common::String EncryptedStream::readLine() {
+	return _readStream->readLine();
+}
+
+int32 EncryptedStream::size() {
+	return _readStream->size();
+}
+
+int32 EncryptedStream::pos() {
+	return _readStream->pos();
+}
+
+EncryptedStream::~EncryptedStream() {
+	delete _readStream;
+}
+
+} // End of namespace CGE