/* Convert files from and to MacBinary format. See docs/formats/MacBinary.md for more information on this format. Copyright (C) 2019, Guillaume Gonnet 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 . */ #include "conv/converters.h" #include "utils/buffer_stream.h" #include "commands.h" namespace maconv { namespace conv { // Precalculed CRC 16 table. static uint16_t kCrc16Table[256] = { 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7, 0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210, 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6, 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D, 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4, 0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC, 0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823, 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B, 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A, 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70, 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E, 0xE16F, 0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067, 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E, 0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D, 0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634, 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3, 0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A, 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92, 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1, 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0 }; // Calculate CRC (Cyclic Redundancy Check) for some data. static uint16_t CalculateCRC(uint8_t *data, uint32_t size) { uint16_t crc = 0; for (uint8_t *end = data + size; data != end; data++) crc = (crc << 8) ^ kCrc16Table[(*data ^ (crc >> 8)) & 0x00FF]; return crc; } // Return true if a file is in MacBinary format. bool IsFileMacBinary(fs::FileReader &reader) { IS_COND(reader.file_size >= 128); IS_COND(reader.ReadByte() == 0x0); auto byte = reader.ReadByte(); IS_COND(byte > 0 && byte < 64); IS_COND(reader.ReadWordBE() > 0x1F000000); reader.Skip(68); // Byte #74 IS_COND(reader.ReadByte() == 0x0); reader.Skip(7); // Byte #82 IS_COND(reader.ReadByte() == 0x0); reader.Skip(39); // Byte #122 auto half = reader.ReadHalfBE(); IS_COND(half == 0 || half == 0x8181 || half == 0x8281); return true; } // Read and decode a MacBinary file. void ReadMacBinary(fs::FileReader &reader, fs::File &file) { reader.Skip(1); // Read name of the file. uint8_t filelength = reader.ReadByte(); file.filename = reader.ReadString(filelength); reader.Skip(63 - filelength); // Read file type, creator and Finder flags. file.type = reader.ReadWordBE(); file.creator = reader.ReadWordBE(); file.flags = reader.ReadByte() << 8; // Read window information. reader.Skip(1); reader.Skip(4); // TODO: read file positions within its window. reader.Skip(4); // TODO: read folder ID and protected flags. // Read size of forks. file.data_size = reader.ReadWordBE(); file.res_size = reader.ReadWordBE(); // Read creation and modification dates. file.creation_date = reader.ReadMacDate(); file.modif_date = reader.ReadMacDate(); // Read second part of Finder flags. reader.Skip(2); file.flags |= reader.ReadByte(); reader.Skip(22); // Assume that CRC is correct. // Set data and resource forks. file.data = reader.data + 128; file.res = reader.data + 128 + ((file.data_size + 127) & -128); } // Write a MacBinary file. void WriteMacBinary(fs::File &file, fs::FileWriter &base) { utils::BufferStreamBuf header_buf {124}; std::ostream header_stream {&header_buf}; fs::FileWriter writer {header_stream}; // Write filename. writer.WriteByte(0x0); writer.WriteByte(file.filename.size()); writer.WriteString(file.filename); writer.Fill(0x0, 63 - file.filename.size()); // Write file type, creator and Finder flags. writer.WriteWordBE(file.type); writer.WriteWordBE(file.creator); writer.WriteByte(file.flags >> 8); // Write window information. writer.Fill(0x0, 1); writer.Fill(0x0, 4); // TODO: write file positions within its window. writer.Fill(0x0, 4); // TODO: write folder ID and protected flags. // Write size of ressource and data forks. writer.WriteWordBE(file.data_size); writer.WriteWordBE(file.res_size); // Write creation and modification dates. writer.WriteMacDate(file.creation_date); writer.WriteMacDate(file.modif_date); // Write second part of Finder flags. writer.Fill(0x0, 2); writer.WriteByte(file.flags & 0xFF); // Write MacBinray III magic strings/numbers. writer.WriteString("mBIN"); writer.Fill(0x0, 16); writer.WriteByte(130); writer.WriteByte(129); // Calculate CRC and write the header. uint8_t *header_data = header_buf.buffer.get(); base.Write(header_data, 124); base.WriteHalfBE(CalculateCRC(header_data, 124)); // Write data fork. base.Fill(0x0, 2); base.Write(file.data, file.data_size); // Write ressource fork. base.Fill(0x7F, ((file.data_size + 127) & -128) - file.data_size); base.Write(file.res, file.res_size); // Write remaning padding. base.Fill(0x7F, ((file.res_size + 127) & -128) - file.res_size); } } // namespace maconv } // namespace conv