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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 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/endian.h"
#include "sci/sci.h"
#include "sci/exereader.h"
namespace Sci {
int _bitCount;
uint16 _bits;
Common::Platform getGameExePlatform(Common::SeekableReadStream *exeStream) {
byte magic[4];
// Make sure that the executable is at least 4KB big
if (exeStream->size() < 4096)
return Common::kPlatformUnknown;
// Read exe header
exeStream->read(magic, 4);
// Check if the header contains known magic bytes
// Information obtained from http://magicdb.org/magic.db
// Check if it's a DOS executable
if (magic[0] == 'M' && magic[1] == 'Z') {
return Common::kPlatformPC;
}
// Check if it's an Amiga executable
if ((magic[2] == 0x03 && magic[3] == 0xF3) ||
(magic[0] == 0x7F && magic[1] == 'E' && magic[2] == 'L' && magic[3] == 'F')) {
return Common::kPlatformAmiga;
}
// Check if it's an Atari executable
if ((magic[0] == 0x60 && magic[1] == 0x1A))
return Common::kPlatformAtariST;
// Check if it's a Mac exe
// Resource map offset
int32 offset = (int32)READ_BE_UINT32(magic);
offset += 28;
if (exeStream->size() <= offset)
return Common::kPlatformUnknown;
// Skip number of types in map
exeStream->skip(2);
// uint16 val = exeStream->readUint16BE() + 1;
exeStream->skip(2);
// Keep reading till we find the "CODE" bit
while (!exeStream->eos()) {
exeStream->skip(4);
if (exeStream->eos())
return Common::kPlatformUnknown;
exeStream->read(magic, 4);
if (exeStream->eos())
return Common::kPlatformUnknown;
if (!memcmp(magic, "CODE", 4)) {
return Common::kPlatformMacintosh;
}
// Skip to the next list entry
exeStream->skip(4);
if (exeStream->eos())
return Common::kPlatformUnknown;
}
// If we've reached here, the file type is unknown
return Common::kPlatformUnknown;
}
uint getBit(Common::SeekableReadStream *input) {
uint bit = _bits & 1;
_bitCount--;
if (_bitCount <= 0) {
_bits = input->readByte();
_bits |= input->readByte() << 8;
if (_bitCount == -1) { // special case for first bit word
bit = _bits & 1;
_bits >>= 1;
}
_bitCount += 16;
} else
_bits >>= 1;
return bit;
}
} // End of namespace Sci
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