blob: f9bc8a3706574ad4453a10e91a94f2c112507876 [file] [log] [blame]
/*
* Copyright (C) 2016 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
import * as assert from 'assert.js';
import * as WASM from 'WASM.js';
const _initialAllocationSize = 1024;
const _growAllocationSize = allocated => allocated * 2;
export const varuint32Min = 0;
export const varint7Min = -0b1000000;
export const varint7Max = 0b111111;
export const varuint7Max = 0b1111111;
export const varuint32Max = ((((1 << 31) >>> 0) - 1) * 2) + 1;
export const varint32Min = -((1 << 31) >>> 0);
export const varint32Max = ((1 << 31) - 1) >>> 0;
export const varBitsMax = 5;
const _getterRangeCheck = (llb, at, size) => {
if (0 > at || at + size > llb._used)
throw new RangeError(`[${at}, ${at + size}) is out of buffer range [0, ${llb._used})`);
};
const _hexdump = (buf, size) => {
let s = "";
const width = 16;
const base = 16;
for (let row = 0; row * width < size; ++row) {
const address = (row * width).toString(base);
s += "0".repeat(8 - address.length) + address;
let chars = "";
for (let col = 0; col !== width; ++col) {
const idx = row * width + col;
if (idx < size) {
const byte = buf[idx];
const bytestr = byte.toString(base);
s += " " + (bytestr.length === 1 ? "0" + bytestr : bytestr);
chars += 0x20 <= byte && byte < 0x7F ? String.fromCharCode(byte) : "ยท";
} else {
s += " ";
chars += " ";
}
}
s+= " |" + chars + "|\n";
}
return s;
};
export default class LowLevelBinary {
constructor() {
this._buf = new Uint8Array(_initialAllocationSize);
this._used = 0;
}
newPatchable(type) { return new PatchableLowLevelBinary(type, this); }
// Utilities.
get() { return this._buf; }
trim() { this._buf = this._buf.slice(0, this._used); }
hexdump() { return _hexdump(this._buf, this._used); }
_maybeGrow(bytes) {
const allocated = this._buf.length;
if (allocated - this._used < bytes) {
let buf = new Uint8Array(_growAllocationSize(allocated));
buf.set(this._buf);
this._buf = buf;
}
}
_push8(v) { this._buf[this._used] = v & 0xFF; this._used += 1; }
// Data types.
uint8(v) {
if ((v & 0xFF) >>> 0 !== v)
throw new RangeError(`Invalid uint8 ${v}`);
this._maybeGrow(1);
this._push8(v);
}
uint16(v) {
if ((v & 0xFFFF) >>> 0 !== v)
throw new RangeError(`Invalid uint16 ${v}`);
this._maybeGrow(2);
this._push8(v);
this._push8(v >>> 8);
}
uint24(v) {
if ((v & 0xFFFFFF) >>> 0 !== v)
throw new RangeError(`Invalid uint24 ${v}`);
this._maybeGrow(3);
this._push8(v);
this._push8(v >>> 8);
this._push8(v >>> 16);
}
uint32(v) {
if ((v & 0xFFFFFFFF) >>> 0 !== v)
throw new RangeError(`Invalid uint32 ${v}`);
this._maybeGrow(4);
this._push8(v);
this._push8(v >>> 8);
this._push8(v >>> 16);
this._push8(v >>> 24);
}
float(v) {
if (isNaN(v))
throw new RangeError("unimplemented, NaNs");
// Unfortunately, we cannot just view the actual buffer as a Float32Array since it needs to be 4 byte aligned
let buffer = new ArrayBuffer(4);
let floatView = new Float32Array(buffer);
let int8View = new Uint8Array(buffer);
floatView[0] = v;
for (let byte of int8View)
this._push8(byte);
}
double(v) {
if (isNaN(v))
throw new RangeError("unimplemented, NaNs");
// Unfortunately, we cannot just view the actual buffer as a Float64Array since it needs to be 4 byte aligned
let buffer = new ArrayBuffer(8);
let floatView = new Float64Array(buffer);
let int8View = new Uint8Array(buffer);
floatView[0] = v;
for (let byte of int8View)
this._push8(byte);
}
varuint32(v) {
assert.isNumber(v);
if (v < varuint32Min || varuint32Max < v)
throw new RangeError(`Invalid varuint32 ${v} range is [${varuint32Min}, ${varuint32Max}]`);
while (v >= 0x80) {
this.uint8(0x80 | (v & 0x7F));
v >>>= 7;
}
this.uint8(v);
}
varint32(v) {
assert.isNumber(v);
if (v < varint32Min || varint32Max < v)
throw new RangeError(`Invalid varint32 ${v} range is [${varint32Min}, ${varint32Max}]`);
do {
const b = v & 0x7F;
v >>= 7;
if ((v === 0 && ((b & 0x40) === 0)) || (v === -1 && ((b & 0x40) === 0x40))) {
this.uint8(b & 0x7F);
break;
}
this.uint8(0x80 | b);
} while (true);
}
varuint64(v) {
assert.isNumber(v);
if (v < varuint32Min || varuint32Max < v)
throw new RangeError(`unimplemented: varuint64 larger than 32-bit`);
this.varuint32(v); // FIXME implement 64-bit var{u}int https://bugs.webkit.org/show_bug.cgi?id=163420
}
varint64(v) {
assert.isNumber(v);
if (v < varint32Min || varint32Max < v)
throw new RangeError(`unimplemented: varint64 larger than 32-bit`);
this.varint32(v); // FIXME implement 64-bit var{u}int https://bugs.webkit.org/show_bug.cgi?id=163420
}
varuint1(v) {
if (v !== 0 && v !== 1)
throw new RangeError(`Invalid varuint1 ${v} range is [0, 1]`);
this.varuint32(v);
}
varint7(v) {
if (v < varint7Min || varint7Max < v)
throw new RangeError(`Invalid varint7 ${v} range is [${varint7Min}, ${varint7Max}]`);
this.varint32(v);
}
varuint7(v) {
if (v < varuint32Min || varuint7Max < v)
throw new RangeError(`Invalid varuint7 ${v} range is [${varuint32Min}, ${varuint7Max}]`);
this.varuint32(v);
}
block_type(v) {
if (!WASM.isValidBlockType(v))
throw new Error(`Invalid block type ${v}`);
this.varint7(WASM.typeValue[v]);
}
string(str) {
let patch = this.newPatchable("varuint32");
for (const char of str) {
// Encode UTF-8 2003 code points.
const code = char.codePointAt();
if (code <= 0x007F) {
const utf8 = code;
patch.uint8(utf8);
} else if (code <= 0x07FF) {
const utf8 = 0x80C0 | ((code & 0x7C0) >> 6) | ((code & 0x3F) << 8);
patch.uint16(utf8);
} else if (code <= 0xFFFF) {
const utf8 = 0x8080E0 | ((code & 0xF000) >> 12) | ((code & 0xFC0) << 2) | ((code & 0x3F) << 16);
patch.uint24(utf8);
} else if (code <= 0x10FFFF) {
const utf8 = (0x808080F0 | ((code & 0x1C0000) >> 18) | ((code & 0x3F000) >> 4) | ((code & 0xFC0) << 10) | ((code & 0x3F) << 24)) >>> 0;
patch.uint32(utf8);
} else
throw new Error(`Unexpectedly large UTF-8 character code point '${char}' 0x${code.toString(16)}`);
}
patch.apply();
}
// Getters.
getSize() { return this._used; }
getUint8(at) {
_getterRangeCheck(this, at, 1);
return this._buf[at];
}
getUint16(at) {
_getterRangeCheck(this, at, 2);
return this._buf[at] | (this._buf[at + 1] << 8);
}
getUint24(at) {
_getterRangeCheck(this, at, 3);
return this._buf[at] | (this._buf[at + 1] << 8) | (this._buf[at + 2] << 16);
}
getUint32(at) {
_getterRangeCheck(this, at, 4);
return (this._buf[at] | (this._buf[at + 1] << 8) | (this._buf[at + 2] << 16) | (this._buf[at + 3] << 24)) >>> 0;
}
getVaruint32(at) {
let v = 0;
let shift = 0;
let byte = 0;
do {
byte = this.getUint8(at++);
++read;
v = (v | ((byte & 0x7F) << shift) >>> 0) >>> 0;
shift += 7;
} while ((byte & 0x80) !== 0);
if (shift - 7 > 32) throw new RangeError(`Shifting too much at ${at}`);
if ((shift == 35) && ((byte & 0xF0) != 0)) throw new Error(`Unexpected non-significant varuint32 bits in last byte 0x${byte.toString(16)}`);
return { value: v, next: at };
}
getVarint32(at) {
let v = 0;
let shift = 0;
let byte = 0;
do {
byte = this.getUint8(at++);
v = (v | ((byte & 0x7F) << shift) >>> 0) >>> 0;
shift += 7;
} while ((byte & 0x80) !== 0);
if (shift - 7 > 32) throw new RangeError(`Shifting too much at ${at}`);
if ((shift == 35) && (((byte << 26) >> 30) != ((byte << 25) >> 31))) throw new Error(`Unexpected non-significant varint32 bits in last byte 0x${byte.toString(16)}`);
if ((byte & 0x40) === 0x40) {
const sext = shift < 32 ? 32 - shift : 0;
v = (v << sext) >> sext;
}
return { value: v, next: at };
}
getVaruint1(at) {
const res = this.getVaruint32(at);
if (res.value !== 0 && res.value !== 1) throw new Error(`Expected a varuint1, got value ${res.value}`);
return res;
}
getVaruint7(at) {
const res = this.getVaruint32(at);
if (res.value > varuint7Max) throw new Error(`Expected a varuint7, got value ${res.value}`);
return res;
}
getString(at) {
const size = this.getVaruint32(at);
const last = size.next + size.value;
let i = size.next;
let str = "";
while (i < last) {
// Decode UTF-8 2003 code points.
const peek = this.getUint8(i);
let code;
if ((peek & 0x80) === 0x0) {
const utf8 = this.getUint8(i);
assert.eq(utf8 & 0x80, 0x00);
i += 1;
code = utf8;
} else if ((peek & 0xE0) === 0xC0) {
const utf8 = this.getUint16(i);
assert.eq(utf8 & 0xC0E0, 0x80C0);
i += 2;
code = ((utf8 & 0x1F) << 6) | ((utf8 & 0x3F00) >> 8);
} else if ((peek & 0xF0) === 0xE0) {
const utf8 = this.getUint24(i);
assert.eq(utf8 & 0xC0C0F0, 0x8080E0);
i += 3;
code = ((utf8 & 0xF) << 12) | ((utf8 & 0x3F00) >> 2) | ((utf8 & 0x3F0000) >> 16);
} else if ((peek & 0xF8) === 0xF0) {
const utf8 = this.getUint32(i);
assert.eq((utf8 & 0xC0C0C0F8) | 0, 0x808080F0 | 0);
i += 4;
code = ((utf8 & 0x7) << 18) | ((utf8 & 0x3F00) << 4) | ((utf8 & 0x3F0000) >> 10) | ((utf8 & 0x3F000000) >> 24);
} else
throw new Error(`Unexpectedly large UTF-8 initial byte 0x${peek.toString(16)}`);
str += String.fromCodePoint(code);
}
if (i !== last)
throw new Error(`String decoding read up to ${i}, expected ${last}, UTF-8 decoding was too greedy`);
return str;
}
};
class PatchableLowLevelBinary extends LowLevelBinary {
constructor(type, lowLevelBinary) {
super();
this.type = type;
this.target = lowLevelBinary;
this._buffered_bytes = 0;
}
_push8(v) { ++this._buffered_bytes; super._push8(v); }
apply() {
this.target[this.type](this._buffered_bytes);
for (let i = 0; i < this._buffered_bytes; ++i)
this.target.uint8(this._buf[i]);
}
};