diff options
| -rw-r--r-- | engines/adl/disk.cpp | 64 |
1 files changed, 48 insertions, 16 deletions
diff --git a/engines/adl/disk.cpp b/engines/adl/disk.cpp index 6952fb973d..6384daad4a 100644 --- a/engines/adl/disk.cpp +++ b/engines/adl/disk.cpp @@ -39,6 +39,38 @@ static Common::SeekableReadStream *readImage(const Common::String &filename) { return f; } +static bool detectDOS33_NIB(const Common::String &filename) { + Common::File f; + + if (!f.open(filename)) + error("Failed to open '%s'", filename.c_str()); + + if (f.size() != 232960) + error("Unrecognized NIB image '%s' of size %d bytes", filename.c_str(), f.size()); + + uint count = 0; + uint dos32 = 0, dos33 = 0; + uint32 window = 0; + + while (count++ < 6656) { + window &= 0xffff; + window <<= 8; + window |= f.readByte(); + + if (f.err() || f.eos()) + error("Failed to read '%s'", filename.c_str()); + + if (window == 0xd5aa96) + ++dos33; + else if (window == 0xd5aab5) + ++dos32; + } + + f.close(); + + return dos33 > dos32; +} + const uint trackLen = 256 * 26; // 4-and-4 encoding (odd-even) @@ -48,7 +80,7 @@ static uint8 read44(byte *buffer, uint &pos) { return ((ret << 1) | 1) & buffer[pos++ % trackLen]; } -static Common::SeekableReadStream *readImage_NIB(const Common::String &filename) { +static Common::SeekableReadStream *readImage_NIB(const Common::String &filename, bool dos33) { Common::File f; if (!f.open(filename)) @@ -62,15 +94,13 @@ static Common::SeekableReadStream *readImage_NIB(const Common::String &filename) // starting at 0x96, 64 is invalid (see below) const byte c_6and2_lookup[] = { 0, 1, 64, 64, 2, 3, 64, 4, 5, 6, 64, 64, 64, 64, 64, 64, 7, 8, 64, 64, 64, 9, 10, 11, 12, 13, 64, 64, 14, 15, 16, 17, 18, 19, 64, 20, 21, 22, 23, 24, 25, 26, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 27, 64, 28, 29, 30, 64, 64, 64, 31, 64, 64, 32, 33, 64, 34, 35, 36, 37, 38, 39, 40, 64, 64, 64, 64, 64, 41, 42, 43, 64, 44, 45, 46, 47, 48, 49, 50, 64, 64, 51, 52, 53, 54, 55, 56, 64, 57, 58, 59, 60, 61, 62, 63 }; - // we always pad it out - const uint sectorsPerTrack = 16; + const uint sectorsPerTrack = (dos33 ? 16 : 13); const uint bytesPerSector = 256; const uint imageSize = 35 * sectorsPerTrack * bytesPerSector; byte *const diskImage = (byte *)calloc(imageSize, 1); bool sawAddress = false; uint8 volNo = 0, track = 0, sector = 0; - bool newStyle; byte buffer[trackLen]; uint firstGoodTrackPos = 0; @@ -92,20 +122,17 @@ static Common::SeekableReadStream *readImage_NIB(const Common::String &filename) byte prologue = buffer[pos++ % trackLen]; - if (sawAddress && (prologue == 0xb5 || prologue == 0x96)) { + if (sawAddress && prologue == (dos33 ? 0x96 : 0xb5)) { sawAddress = false; } if (!sawAddress) { sawAddress = true; - newStyle = false; // We should always find the address field first. - if (prologue != 0xb5) { + if (prologue != (dos33 ? 0x96 : 0xb5)) { // Accept a DOS 3.3(?) header at the start. - if (prologue == 0x96) { - newStyle = true; - } else if (prologue == 0xad || prologue == 0xfd) { + if (prologue == (dos33 ? 0xb5 : 0x96) || prologue == 0xad || prologue == 0xfd) { sawAddress = false; continue; } else { @@ -136,7 +163,7 @@ static Common::SeekableReadStream *readImage_NIB(const Common::String &filename) // TODO: we ignore volNo? byte *output = diskImage + (track * sectorsPerTrack + sector) * bytesPerSector; - if (newStyle) { + if (dos33) { // We hardcode the DOS 3.3 mapping here. TODO: Do we also need raw/prodos? int raw2dos[16] = { 0, 7, 14, 6, 13, 5, 12, 4, 11, 3, 10, 2, 9, 1, 8, 15 }; sector = raw2dos[sector]; @@ -250,25 +277,30 @@ bool DiskImage::open(const Common::String &filename) { lcName.toLowercase(); if (lcName.hasSuffix(".dsk")) { - _stream = readImage(filename); _tracks = 35; _sectorsPerTrack = 16; _bytesPerSector = 256; - } else if (lcName.hasSuffix(".d13")) { _stream = readImage(filename); + } else if (lcName.hasSuffix(".d13")) { _tracks = 35; _sectorsPerTrack = 13; _bytesPerSector = 256; + _stream = readImage(filename); } else if (lcName.hasSuffix(".nib")) { - _stream = readImage_NIB(filename); _tracks = 35; - _sectorsPerTrack = 16; + + if (detectDOS33_NIB(filename)) + _sectorsPerTrack = 16; + else + _sectorsPerTrack = 13; + _bytesPerSector = 256; + _stream = readImage_NIB(filename, _sectorsPerTrack == 16); } else if (lcName.hasSuffix(".xfd")) { - _stream = readImage(filename); _tracks = 40; _sectorsPerTrack = 18; _bytesPerSector = 128; + _stream = readImage(filename); } int expectedSize = _tracks * _sectorsPerTrack * _bytesPerSector; |