js-mdict
Version:
mdict (*.mdx, *.mdd) file reader. Licensed under AGPL-3.0 for better community cooperation and commercial value protection.
568 lines • 22.4 kB
JavaScript
"use strict";
/*
* minilzo-js
* JavaScript port of minilzo by Alistair Braidwood
*
*
* This library 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.
*
* You should have received a copy of the GNU General Public License
* along with the minilzo-js library; see the file COPYING.
* If not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
Object.defineProperty(exports, "__esModule", { value: true });
/*
* original minilzo.c by:
*
* Markus F.X.J. Oberhumer
* <markus@oberhumer.com>
* http://www.oberhumer.com/opensource/lzo/
*/
/*
* NOTE:
* the full LZO package can be found at
* http://www.oberhumer.com/opensource/lzo/
*/
const lzo1x = function lzo1x() {
function _lzo1x() { }
_lzo1x.prototype = {
blockSize: 4096,
OK: 0,
INPUT_OVERRUN: -4,
OUTPUT_OVERRUN: -5,
LOOKBEHIND_OVERRUN: -6,
EOF_FOUND: -999,
buf: null,
buf32: null,
out: null,
out32: null,
cbl: 0,
ip_end: 0,
op_end: 0,
t: 0,
ip: 0,
op: 0,
m_pos: 0,
skipToFirstLiteralFun: false,
ctzl(v) {
// this might be needed for _compressCore (it isn't in my current tests files)
/*
* https://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightBinSearch
* Matt Whitlock suggested this on January 25, 2006.
* Andrew Shapira shaved a couple operations off on Sept. 5,
* 2007 (by setting c=1 and unconditionally subtracting at the end).
*/
let c; // c will be the number of zero bits on the right,
// so if v is 1101000 (base 2), then c will be 3
// NOTE: if 0 == v, then c = 31.
if (v & 0x1) {
// special case for odd v (assumed to happen half of the time)
c = 0;
}
else {
c = 1;
if ((v & 0xffff) === 0) {
v >>= 16;
c += 16;
}
if ((v & 0xff) === 0) {
v >>= 8;
c += 8;
}
if ((v & 0xf) === 0) {
v >>= 4;
c += 4;
}
if ((v & 0x3) === 0) {
v >>= 2;
c += 2;
}
c -= v & 0x1;
}
return c;
},
extendBuffer() {
const newBuffer = new Uint8Array(this.cbl + this.blockSize);
newBuffer.set(this.out);
this.out = newBuffer;
this.out32 = new Uint32Array(this.out.buffer);
this.state.outputBuffer = this.out;
this.cbl = this.out.length;
},
eof_found() {
// *out_len = ((lzo_uint) ((op)-(out)));
return this.ip === this.ip_end ? 0 : this.ip < this.ip_end ? -8 : -4;
},
match_next() {
// if (op_end - op < t) return OUTPUT_OVERRUN;
// if (ip_end - ip < t+3) return INPUT_OVERRUN;
while (this.op + 3 > this.cbl) {
this.extendBuffer();
}
this.out[this.op++] = this.buf[this.ip++];
if (this.t > 1) {
this.out[this.op++] = this.buf[this.ip++];
if (this.t > 2) {
this.out[this.op++] = this.buf[this.ip++];
}
}
this.t = this.buf[this.ip++];
},
match_done() {
this.t = this.buf[this.ip - 2] & 3;
return this.t;
},
copy_match() {
this.t += 2;
while (this.op + this.t > this.cbl) {
this.extendBuffer();
}
if (this.t > 4 && this.op % 4 === this.m_pos % 4) {
while (this.op % 4 > 0) {
this.out[this.op++] = this.out[this.m_pos++];
this.t--;
}
while (this.t > 4) {
this.out32[0 | (this.op / 4)] = this.out32[0 | (this.m_pos / 4)];
this.op += 4;
this.m_pos += 4;
this.t -= 4;
}
}
do {
this.out[this.op++] = this.out[this.m_pos++];
} while (--this.t > 0);
},
copy_from_buf() {
while (this.op + this.t > this.cbl) {
this.extendBuffer();
}
if (this.t > 4 && this.op % 4 === this.ip % 4) {
while (this.op % 4 > 0) {
this.out[this.op++] = this.buf[this.ip++];
this.t--;
}
while (this.t > 4) {
this.out32[0 | (this.op / 4)] = this.buf32[0 | (this.ip / 4)];
this.op += 4;
this.ip += 4;
this.t -= 4;
}
}
do {
this.out[this.op++] = this.buf[this.ip++];
} while (--this.t > 0);
},
match() {
for (;;) {
if (this.t >= 64) {
this.m_pos = this.op - 1;
this.m_pos -= (this.t >> 2) & 7;
this.m_pos -= this.buf[this.ip++] << 3;
this.t = (this.t >> 5) - 1;
// if ( m_pos < out || m_pos >= op) return LOOKBEHIND_OVERRUN;
// if (op_end - op < t+3-1) return OUTPUT_OVERRUN;
this.copy_match();
if (this.match_done() === 0) {
break;
}
else {
this.match_next();
continue;
}
}
else if (this.t >= 32) {
this.t &= 31;
if (this.t === 0) {
while (this.buf[this.ip] === 0) {
this.t += 255;
this.ip++;
// if (t > -511) return OUTPUT_OVERRUN;
// if (ip_end - ip < 1) return INPUT_OVERRUN;
}
this.t += 31 + this.buf[this.ip++];
// if (ip_end - ip < 2) return INPUT_OVERRUN;
}
this.m_pos = this.op - 1;
this.m_pos -= (this.buf[this.ip] >> 2) + (this.buf[this.ip + 1] << 6);
this.ip += 2;
}
else if (this.t >= 16) {
this.m_pos = this.op;
this.m_pos -= (this.t & 8) << 11;
this.t &= 7;
if (this.t === 0) {
while (this.buf[this.ip] === 0) {
this.t += 255;
this.ip++;
// if (t > -511) return OUTPUT_OVERRUN;
// if (ip_end - ip < 1) return INPUT_OVERRUN;
}
this.t += 7 + this.buf[this.ip++];
// if (ip_end - ip < 2) return INPUT_OVERRUN;
}
this.m_pos -= (this.buf[this.ip] >> 2) + (this.buf[this.ip + 1] << 6);
this.ip += 2;
if (this.m_pos === this.op) {
this.state.outputBuffer = this.state.outputBuffer.subarray(0, this.op);
return this.EOF_FOUND;
}
this.m_pos -= 0x4000;
}
else {
this.m_pos = this.op - 1;
this.m_pos -= this.t >> 2;
this.m_pos -= this.buf[this.ip++] << 2;
// if (m_pos < out || m_pos >= op) return LOOKBEHIND_OVERRUN;
// if (op_end - op < 2) return OUTPUT_OVERRUN;
while (this.op + 2 > this.cbl) {
this.extendBuffer();
}
this.out[this.op++] = this.out[this.m_pos++];
this.out[this.op++] = this.out[this.m_pos];
if (this.match_done() === 0) {
break;
}
else {
this.match_next();
continue;
}
}
// if (m_pos < out || m_pos >= op) return LOOKBEHIND_OVERRUN;
// if (op_end - op < t+3-1) return OUTPUT_OVERRUN;
this.copy_match();
if (this.match_done() === 0) {
break;
}
this.match_next();
}
return this.OK;
},
decompress(state) {
this.state = state;
this.buf = this.state.inputBuffer;
const buf_4b = new Uint8Array(this.buf.length + (4 - (this.buf.length % 4)));
buf_4b.set(this.buf);
this.buf32 = new Uint32Array(buf_4b.buffer);
this.out = new Uint8Array(this.buf.length + (this.blockSize - (this.buf.length % this.blockSize)));
this.out32 = new Uint32Array(this.out.buffer);
this.cbl = this.out.length;
this.state.outputBuffer = this.out;
this.ip_end = this.buf.length;
this.op_end = this.out.length;
this.t = 0;
this.ip = 0;
this.op = 0;
this.m_pos = 0;
this.skipToFirstLiteralFun = false;
// if (ip_end - ip < 1) return INPUT_OVERRUN;
if (this.buf[this.ip] > 17) {
this.t = this.buf[this.ip++] - 17;
if (this.t < 4) {
this.match_next();
const ret = this.match();
if (ret !== this.OK) {
return ret === this.EOF_FOUND ? this.OK : ret;
}
}
else {
// if (op_end - op < t) return OUTPUT_OVERRUN;
// if (ip_end - ip < t+3) return INPUT_OVERRUN;
this.copy_from_buf();
this.skipToFirstLiteralFun = true;
}
}
for (;;) {
if (!this.skipToFirstLiteralFun) {
// if (ip_end - ip < 3) return INPUT_OVERRUN;
this.t = this.buf[this.ip++];
if (this.t >= 16) {
const ret = this.match();
if (ret !== this.OK) {
return ret === this.EOF_FOUND ? this.OK : ret;
}
continue;
}
if (this.t === 0) {
while (this.buf[this.ip] === 0) {
this.t += 255;
this.ip++;
// if (t > 511) return INPUT_OVERRUN;
// if (ip_end - ip < 1) return INPUT_OVERRUN;
}
this.t += 15 + this.buf[this.ip++];
}
// if (op_end - op < t+3) return OUTPUT_OVERRUN;
// if (ip_end - ip < t+6) return INPUT_OVERRUN;
this.t += 3;
this.copy_from_buf();
}
else {
this.skipToFirstLiteralFun = false;
}
this.t = this.buf[this.ip++];
if (this.t < 16) {
this.m_pos = this.op - (1 + 0x0800);
this.m_pos -= this.t >> 2;
this.m_pos -= this.buf[this.ip++] << 2;
// if ( m_pos < out || m_pos >= op) return LOOKBEHIND_OVERRUN;
// if (op_end - op < 3) return OUTPUT_OVERRUN;
while (this.op + 3 > this.cbl) {
this.extendBuffer();
}
this.out[this.op++] = this.out[this.m_pos++];
this.out[this.op++] = this.out[this.m_pos++];
this.out[this.op++] = this.out[this.m_pos];
if (this.match_done() === 0) {
continue;
}
else {
this.match_next();
}
}
const ret = this.match();
if (ret !== this.OK) {
return ret === this.EOF_FOUND ? this.OK : ret;
}
}
// eslint-disable-next-line
return this.OK;
},
_compressCore(in_len, ti) {
const ip_start = this.ip;
const ip_end = this.ip + in_len - 20;
let ii = this.ip;
this.ip += ti < 4 ? 4 - ti : 0;
let m_pos = 0;
let m_off = 0;
let m_len = 0;
let dv_hi = 0;
let dv_lo = 0;
let dindex = 0;
this.ip += 1 + ((this.ip - ii) >> 5);
for (;;) {
if (this.ip >= ip_end) {
break;
}
// dv = this.buf[this.ip] | (this.buf[this.ip + 1] << 8)
// | (this.buf[this.ip + 2] << 16) | (this.buf[this.ip + 3] << 24);
// dindex = ((0x1824429d * dv) >> 18) & 16383;
// The above code doesn't work in JavaScript due to a lack of 64 bit bitwise operations
// Instead, use (optimised two's complement integer arithmetic)
// Optimization is based on us only needing the high 16 bits of the lower 32 bit integer.
dv_lo = this.buf[this.ip] | (this.buf[this.ip + 1] << 8);
dv_hi = this.buf[this.ip + 2] | (this.buf[this.ip + 3] << 8);
dindex =
((((dv_lo * 0x429d) >>> 16) + dv_hi * 0x429d + dv_lo * 0x1824) &
0xffff) >>>
2;
m_pos = ip_start + this.dict[dindex];
this.dict[dindex] = this.ip - ip_start;
// eslint-disable-next-line
if ((dv_hi << 16) + dv_lo !=
(this.buf[m_pos] |
(this.buf[m_pos + 1] << 8) |
(this.buf[m_pos + 2] << 16) |
(this.buf[m_pos + 3] << 24))) {
this.ip += 1 + ((this.ip - ii) >> 5);
continue;
}
ii -= ti;
ti = 0;
let t = this.ip - ii;
if (t !== 0) {
if (t <= 3) {
this.out[this.op - 2] |= t;
do {
this.out[this.op++] = this.buf[ii++];
} while (--t > 0);
}
else {
if (t <= 18) {
this.out[this.op++] = t - 3;
}
else {
let tt = t - 18;
this.out[this.op++] = 0;
while (tt > 255) {
tt -= 255;
this.out[this.op++] = 0;
}
this.out[this.op++] = tt;
}
do {
this.out[this.op++] = this.buf[ii++];
} while (--t > 0);
}
}
m_len = 4;
// var skipTo_m_len_done = false;
if (this.buf[this.ip + m_len] === this.buf[m_pos + m_len]) {
do {
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
m_len += 1;
if (this.buf[this.ip + m_len] !== this.buf[m_pos + m_len]) {
break;
}
if (this.ip + m_len >= ip_end) {
// skipTo_m_len_done = true;
break;
}
} while (this.buf[this.ip + m_len] === this.buf[m_pos + m_len]);
}
// if (!skipTo_m_len_done) {
// var inc = this.ctzl(this.buf[this.ip + m_len] ^ this.buf[m_pos + m_len]) >> 3;
// m_len += inc;
// }
m_off = this.ip - m_pos;
this.ip += m_len;
ii = this.ip;
if (m_len <= 8 && m_off <= 0x0800) {
m_off -= 1;
this.out[this.op++] = ((m_len - 1) << 5) | ((m_off & 7) << 2);
this.out[this.op++] = m_off >> 3;
}
else if (m_off <= 0x4000) {
m_off -= 1;
if (m_len <= 33) {
this.out[this.op++] = 32 | (m_len - 2);
}
else {
m_len -= 33;
this.out[this.op++] = 32;
while (m_len > 255) {
m_len -= 255;
this.out[this.op++] = 0;
}
this.out[this.op++] = m_len;
}
this.out[this.op++] = m_off << 2;
this.out[this.op++] = m_off >> 6;
}
else {
m_off -= 0x4000;
if (m_len <= 9) {
this.out[this.op++] = 16 | ((m_off >> 11) & 8) | (m_len - 2);
}
else {
m_len -= 9;
this.out[this.op++] = 16 | ((m_off >> 11) & 8);
while (m_len > 255) {
m_len -= 255;
this.out[this.op++] = 0;
}
this.out[this.op++] = m_len;
}
this.out[this.op++] = m_off << 2;
this.out[this.op++] = m_off >> 6;
}
}
return in_len - (ii - ip_start - ti);
},
compress(state) {
this.state = state;
this.ip = 0;
this.buf = this.state.inputBuffer;
const in_len = this.buf.length;
const max_len = in_len + Math.ceil(in_len / 16) + 64 + 3;
this.state.outputBuffer = new Uint8Array(max_len);
this.out = this.state.outputBuffer;
this.op = 0;
this.dict = new Uint32Array(16384);
let l = in_len;
let t = 0;
while (l > 20) {
const ll = l <= 49152 ? l : 49152;
if ((t + ll) >> 5 <= 0) {
break;
}
this.dict = new Uint32Array(16384);
const prev_ip = this.ip;
t = this._compressCore(ll, t);
this.ip = prev_ip + ll;
l -= ll;
}
t += l;
if (t > 0) {
let ii = in_len - t;
if (this.op === 0 && t <= 238) {
this.out[this.op++] = 17 + t;
}
else if (t <= 3) {
this.out[this.op - 2] |= t;
}
else if (t <= 18) {
this.out[this.op++] = t - 3;
}
else {
let tt = t - 18;
this.out[this.op++] = 0;
while (tt > 255) {
tt -= 255;
this.out[this.op++] = 0;
}
this.out[this.op++] = tt;
}
do {
this.out[this.op++] = this.buf[ii++];
} while (--t > 0);
}
this.out[this.op++] = 17;
this.out[this.op++] = 0;
this.out[this.op++] = 0;
this.state.outputBuffer = this.out.subarray(0, this.op);
return this.OK;
},
};
// @ts-expect-error ignore error for now
const instance = new _lzo1x();
return {
compress(state) {
const result = instance.compress(state);
if (result == 0) {
return instance.state.outputBuffer;
}
return result;
},
decompress(state) {
const result = instance.decompress(state);
if (result == 0) {
return instance.state.outputBuffer;
}
return result;
},
};
};
exports.default = lzo1x();
//# sourceMappingURL=lzo1x.js.map