apple2js/js/formats/format_utils.js
2019-10-16 20:20:38 -07:00

426 lines
11 KiB
JavaScript

/* Copyright 2010-2019 Will Scullin <scullin@scullinsteel.com>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*/
import { base64_decode, base64_encode } from '../base64';
import { bytify, debug, toHex } from '../util';
// var DO = [0x0,0x7,0xE,0x6,0xD,0x5,0xC,0x4,
// 0xB,0x3,0xA,0x2,0x9,0x1,0x8,0xF];
export var _DO = [
0x0,0xD,0xB,0x9,0x7,0x5,0x3,0x1,
0xE,0xC,0xA,0x8,0x6,0x4,0x2,0xF
];
// var PO = [0x0,0x8,0x1,0x9,0x2,0xa,0x3,0xb,
// 0x4,0xc,0x5,0xd,0x6,0xe,0x7,0xf];
export var _PO = [
0x0,0x2,0x4,0x6,0x8,0xa,0xc,0xe,
0x1,0x3,0x5,0x7,0x9,0xb,0xd,0xf
];
// var D13O = [
// 0x0, 0xa, 0x7, 0x4, 0x1, 0xb, 0x8, 0x5, 0x2, 0xc, 0x9, 0x6, 0x3
// ];
export var _D13O = [
0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc
];
var _trans53 = [
0xab, 0xad, 0xae, 0xaf, 0xb5, 0xb6, 0xb7, 0xba,
0xbb, 0xbd, 0xbe, 0xbf, 0xd6, 0xd7, 0xda, 0xdb,
0xdd, 0xde, 0xdf, 0xea, 0xeb, 0xed, 0xee, 0xef,
0xf5, 0xf6, 0xf7, 0xfa, 0xfb, 0xfd, 0xfe, 0xff
];
var _trans62 = [
0x96, 0x97, 0x9a, 0x9b, 0x9d, 0x9e, 0x9f, 0xa6,
0xa7, 0xab, 0xac, 0xad, 0xae, 0xaf, 0xb2, 0xb3,
0xb4, 0xb5, 0xb6, 0xb7, 0xb9, 0xba, 0xbb, 0xbc,
0xbd, 0xbe, 0xbf, 0xcb, 0xcd, 0xce, 0xcf, 0xd3,
0xd6, 0xd7, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde,
0xdf, 0xe5, 0xe6, 0xe7, 0xe9, 0xea, 0xeb, 0xec,
0xed, 0xee, 0xef, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6,
0xf7, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
];
export var detrans62 = [
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
0x00, 0x00, 0x02, 0x03, 0x00, 0x04, 0x05, 0x06,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0x08,
0x00, 0x00, 0x00, 0x09, 0x0A, 0x0B, 0x0C, 0x0D,
0x00, 0x00, 0x0E, 0x0F, 0x10, 0x11, 0x12, 0x13,
0x00, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x1B, 0x00, 0x1C, 0x1D, 0x1E,
0x00, 0x00, 0x00, 0x1F, 0x00, 0x00, 0x20, 0x21,
0x00, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
0x00, 0x00, 0x00, 0x00, 0x00, 0x29, 0x2A, 0x2B,
0x00, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32,
0x00, 0x00, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38,
0x00, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F
];
/**
* From Beneath Apple DOS
*/
export function fourXfour(val) {
var xx = val & 0xaa;
var yy = val & 0x55;
xx >>= 1;
xx |= 0xaa;
yy |= 0xaa;
return [xx, yy];
}
export function defourXfour(xx, yy) {
return ((xx << 1) | 0x01) & yy;
}
export function explodeSector16(volume, track, sector, data) {
var checksum;
var buf = [], idx;
var gap;
/*
* Gap 1/3 (40/0x28 bytes)
*/
if (sector === 0) // Gap 1
gap = 0x80;
else { // Gap 3
gap = track === 0 ? 0x28 : 0x26;
}
for (idx = 0; idx < gap; idx++) {
buf.push(0xff);
}
/*
* Address Field
*/
checksum = volume ^ track ^ sector;
buf = buf.concat([0xd5, 0xaa, 0x96]); // Address Prolog D5 AA 96
buf = buf.concat(fourXfour(volume));
buf = buf.concat(fourXfour(track));
buf = buf.concat(fourXfour(sector));
buf = buf.concat(fourXfour(checksum));
buf = buf.concat([0xde, 0xaa, 0xeb]); // Epilog DE AA EB
/*
* Gap 2 (5 bytes)
*/
for (idx = 0; idx < 0x05; idx++) {
buf.push(0xff);
}
/*
* Data Field
*/
buf = buf.concat([0xd5, 0xaa, 0xad]); // Data Prolog D5 AA AD
var nibbles = [];
var ptr2 = 0;
var ptr6 = 0x56;
var idx2, idx6;
for (idx = 0; idx < 0x156; idx++) {
nibbles[idx] = 0;
}
idx2 = 0x55;
for (idx6 = 0x101; idx6 >= 0; idx6--) {
var val6 = data[idx6 % 0x100];
var val2 = nibbles[ptr2 + idx2];
val2 = (val2 << 1) | (val6 & 1);
val6 >>= 1;
val2 = (val2 << 1) | (val6 & 1);
val6 >>= 1;
nibbles[ptr6 + idx6] = val6;
nibbles[ptr2 + idx2] = val2;
if (--idx2 < 0)
idx2 = 0x55;
}
var last = 0;
for (idx = 0; idx < 0x156; idx++) {
var val = nibbles[idx];
buf.push(_trans62[last ^ val]);
last = val;
}
buf.push(_trans62[last]);
buf = buf.concat([0xde, 0xaa, 0xf2]); // Epilog DE AA F2
/*
* Gap 3
*/
buf.push(0xff);
return buf;
}
export function explodeSector13(volume, track, sector, data) {
var checksum;
var buf = [], idx;
var gap;
/*
* Gap 1/3 (40/0x28 bytes)
*/
if (sector === 0) // Gap 1
gap = 0x80;
else { // Gap 3
gap = track === 0 ? 0x28 : 0x26;
}
for (idx = 0; idx < gap; idx++) {
buf.push(0xff);
}
/*
* Address Field
*/
checksum = volume ^ track ^ sector;
buf = buf.concat([0xd5, 0xaa, 0xb5]); // Address Prolog D5 AA B5
buf = buf.concat(fourXfour(volume));
buf = buf.concat(fourXfour(track));
buf = buf.concat(fourXfour(sector));
buf = buf.concat(fourXfour(checksum));
buf = buf.concat([0xde, 0xaa, 0xeb]); // Epilog DE AA EB
/*
* Gap 2 (5 bytes)
*/
for (idx = 0; idx < 0x05; idx++) {
buf.push(0xff);
}
/*
* Data Field
*/
buf = buf.concat([0xd5, 0xaa, 0xad]); // Data Prolog D5 AA AD
var nibbles = [];
var jdx = 0;
for (idx = 0x32; idx >= 0; idx--) {
var a5 = data[jdx] >> 3;
var a3 = data[jdx] & 0x07;
jdx++;
var b5 = data[jdx] >> 3;
var b3 = data[jdx] & 0x07;
jdx++;
var c5 = data[jdx] >> 3;
var c3 = data[jdx] & 0x07;
jdx++;
var d5 = data[jdx] >> 3;
var d3 = data[jdx] & 0x07;
jdx++;
var e5 = data[jdx] >> 3;
var e3 = data[jdx] & 0x07;
jdx++;
nibbles[idx + 0x00] = a5;
nibbles[idx + 0x33] = b5;
nibbles[idx + 0x66] = c5;
nibbles[idx + 0x99] = d5;
nibbles[idx + 0xcc] = e5;
nibbles[idx + 0x100] = a3 << 2 | (d3 & 0x4) >> 1 | (e3 & 0x4) >> 2;
nibbles[idx + 0x133] = b3 << 2 | (d3 & 0x2) | (e3 & 0x2) >> 1;
nibbles[idx + 0x166] = c3 << 2 | (d3 & 0x1) << 1 | (e3 & 0x1);
}
nibbles[0xff] = data[jdx] >> 3;
nibbles[0x199] = data[jdx] & 0x07;
var val;
var last = 0;
for (idx = 0x199; idx >= 0x100; idx--) {
val = nibbles[idx];
buf.push(_trans53[last ^ val]);
last = val;
}
for (idx = 0x0; idx < 0x100; idx++) {
val = nibbles[idx];
buf.push(_trans53[last ^ val]);
last = val;
}
buf.push(_trans53[last]);
buf = buf.concat([0xde, 0xaa, 0xeb]); // Epilog DE AA EB
/*
* Gap 3
*/
buf.push(0xff);
return buf;
}
export function readSector(drive, track, sector) {
var _sector = drive.fmt == 'po' ? _PO[sector] : _DO[sector];
var val, state = 0;
var idx = 0;
var retry = 0;
var cur = drive.tracks[track];
function _readNext() {
var result = cur[idx++];
if (idx >= cur.length) {
idx = 0;
retry++;
}
return result;
}
function _skipBytes(count) {
idx += count;
if (idx >= cur.length) {
idx %= cur.length;
retry++;
}
}
var t = 0, s = 0, v = 0, jdx, kdx, checkSum;
var data = [];
while (retry < 4) {
switch (state) {
case 0:
val = _readNext();
state = (val === 0xd5) ? 1 : 0;
break;
case 1:
val = _readNext();
state = (val === 0xaa) ? 2 : 0;
break;
case 2:
val = _readNext();
state = (val === 0x96) ? 3 : (val === 0xad ? 4 : 0);
break;
case 3: // Address
v = defourXfour(_readNext(), _readNext()); // Volume
t = defourXfour(_readNext(), _readNext());
s = defourXfour(_readNext(), _readNext());
checkSum = defourXfour(_readNext(), _readNext());
if (checkSum != (v ^ t ^ s)) {
debug('Invalid header checksum:', toHex(v), toHex(t), toHex(s), toHex(checkSum));
}
_skipBytes(3); // Skip footer
state = 0;
break;
case 4: // Data
if (s === _sector && t === track) {
var data2 = [];
var last = 0;
for (jdx = 0x55; jdx >= 0; jdx--) {
val = detrans62[_readNext() - 0x80] ^ last;
data2[jdx] = val;
last = val;
}
for (jdx = 0; jdx < 0x100; jdx++) {
val = detrans62[_readNext() - 0x80] ^ last;
data[jdx] = val;
last = val;
}
checkSum = detrans62[_readNext() - 0x80] ^ last;
if (checkSum) {
debug('Invalid data checksum:', toHex(v), toHex(t), toHex(s), toHex(checkSum));
}
for (kdx = 0, jdx = 0x55; kdx < 0x100; kdx++) {
data[kdx] <<= 1;
if ((data2[jdx] & 0x01) !== 0) {
data[kdx] |= 0x01;
}
data2[jdx] >>= 1;
data[kdx] <<= 1;
if ((data2[jdx] & 0x01) !== 0) {
data[kdx] |= 0x01;
}
data2[jdx] >>= 1;
if (--jdx < 0) jdx = 0x55;
}
return data;
}
else
_skipBytes(0x159); // Skip data, checksum and footer
state = 0;
break;
default:
break;
}
}
return [];
}
export function jsonEncode(cur, pretty) {
var data = [];
var format = 'dsk';
for (var t = 0; t < cur.tracks.length; t++) {
data[t] = [];
if (cur.format === 'nib') {
format = 'nib';
data[t] = base64_encode(cur.tracks[t]);
} else {
for (var s = 0; s < 0x10; s++) {
data[t][s] = base64_encode(readSector(cur, t));
}
}
}
return JSON.stringify({
'type': format,
'encoding': 'base64',
'volume': cur.volume,
'data': data
}, null, pretty ? ' ' : null);
}
export function jsonDecode(data) {
var cur = {};
var tracks = [];
var json = JSON.parse(data);
var v = json.volume;
for (var t = 0; t < json.data.length; t++) {
var track = [];
for (var s = 0; s < json.data[t].length; s++) {
var _s = 15 - s;
var d = base64_decode(json.data[t][_s]);
track = track.concat(explodeSector16(v, t, s, d));
}
tracks[t] = bytify(track);
}
cur.volume = v;
cur.format = json.type;
cur.tracks = tracks;
cur.trackMap = null;
return cur;
}