package.index.js Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of pbf Show documentation
Show all versions of pbf Show documentation
a low-level, lightweight protocol buffers implementation in JavaScript
The newest version!
'use strict';
module.exports = Pbf;
var ieee754 = require('ieee754');
function Pbf(buf) {
this.buf = ArrayBuffer.isView && ArrayBuffer.isView(buf) ? buf : new Uint8Array(buf || 0);
this.pos = 0;
this.type = 0;
this.length = this.buf.length;
}
Pbf.Varint = 0; // varint: int32, int64, uint32, uint64, sint32, sint64, bool, enum
Pbf.Fixed64 = 1; // 64-bit: double, fixed64, sfixed64
Pbf.Bytes = 2; // length-delimited: string, bytes, embedded messages, packed repeated fields
Pbf.Fixed32 = 5; // 32-bit: float, fixed32, sfixed32
var SHIFT_LEFT_32 = (1 << 16) * (1 << 16),
SHIFT_RIGHT_32 = 1 / SHIFT_LEFT_32;
// Threshold chosen based on both benchmarking and knowledge about browser string
// data structures (which currently switch structure types at 12 bytes or more)
var TEXT_DECODER_MIN_LENGTH = 12;
var utf8TextDecoder = typeof TextDecoder === 'undefined' ? null : new TextDecoder('utf-8');
Pbf.prototype = {
destroy: function() {
this.buf = null;
},
// === READING =================================================================
readFields: function(readField, result, end) {
end = end || this.length;
while (this.pos < end) {
var val = this.readVarint(),
tag = val >> 3,
startPos = this.pos;
this.type = val & 0x7;
readField(tag, result, this);
if (this.pos === startPos) this.skip(val);
}
return result;
},
readMessage: function(readField, result) {
return this.readFields(readField, result, this.readVarint() + this.pos);
},
readFixed32: function() {
var val = readUInt32(this.buf, this.pos);
this.pos += 4;
return val;
},
readSFixed32: function() {
var val = readInt32(this.buf, this.pos);
this.pos += 4;
return val;
},
// 64-bit int handling is based on github.com/dpw/node-buffer-more-ints (MIT-licensed)
readFixed64: function() {
var val = readUInt32(this.buf, this.pos) + readUInt32(this.buf, this.pos + 4) * SHIFT_LEFT_32;
this.pos += 8;
return val;
},
readSFixed64: function() {
var val = readUInt32(this.buf, this.pos) + readInt32(this.buf, this.pos + 4) * SHIFT_LEFT_32;
this.pos += 8;
return val;
},
readFloat: function() {
var val = ieee754.read(this.buf, this.pos, true, 23, 4);
this.pos += 4;
return val;
},
readDouble: function() {
var val = ieee754.read(this.buf, this.pos, true, 52, 8);
this.pos += 8;
return val;
},
readVarint: function(isSigned) {
var buf = this.buf,
val, b;
b = buf[this.pos++]; val = b & 0x7f; if (b < 0x80) return val;
b = buf[this.pos++]; val |= (b & 0x7f) << 7; if (b < 0x80) return val;
b = buf[this.pos++]; val |= (b & 0x7f) << 14; if (b < 0x80) return val;
b = buf[this.pos++]; val |= (b & 0x7f) << 21; if (b < 0x80) return val;
b = buf[this.pos]; val |= (b & 0x0f) << 28;
return readVarintRemainder(val, isSigned, this);
},
readVarint64: function() { // for compatibility with v2.0.1
return this.readVarint(true);
},
readSVarint: function() {
var num = this.readVarint();
return num % 2 === 1 ? (num + 1) / -2 : num / 2; // zigzag encoding
},
readBoolean: function() {
return Boolean(this.readVarint());
},
readString: function() {
var end = this.readVarint() + this.pos;
var pos = this.pos;
this.pos = end;
if (end - pos >= TEXT_DECODER_MIN_LENGTH && utf8TextDecoder) {
// longer strings are fast with the built-in browser TextDecoder API
return readUtf8TextDecoder(this.buf, pos, end);
}
// short strings are fast with our custom implementation
return readUtf8(this.buf, pos, end);
},
readBytes: function() {
var end = this.readVarint() + this.pos,
buffer = this.buf.subarray(this.pos, end);
this.pos = end;
return buffer;
},
// verbose for performance reasons; doesn't affect gzipped size
readPackedVarint: function(arr, isSigned) {
if (this.type !== Pbf.Bytes) return arr.push(this.readVarint(isSigned));
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readVarint(isSigned));
return arr;
},
readPackedSVarint: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readSVarint());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readSVarint());
return arr;
},
readPackedBoolean: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readBoolean());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readBoolean());
return arr;
},
readPackedFloat: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readFloat());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readFloat());
return arr;
},
readPackedDouble: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readDouble());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readDouble());
return arr;
},
readPackedFixed32: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readFixed32());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readFixed32());
return arr;
},
readPackedSFixed32: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readSFixed32());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readSFixed32());
return arr;
},
readPackedFixed64: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readFixed64());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readFixed64());
return arr;
},
readPackedSFixed64: function(arr) {
if (this.type !== Pbf.Bytes) return arr.push(this.readSFixed64());
var end = readPackedEnd(this);
arr = arr || [];
while (this.pos < end) arr.push(this.readSFixed64());
return arr;
},
skip: function(val) {
var type = val & 0x7;
if (type === Pbf.Varint) while (this.buf[this.pos++] > 0x7f) {}
else if (type === Pbf.Bytes) this.pos = this.readVarint() + this.pos;
else if (type === Pbf.Fixed32) this.pos += 4;
else if (type === Pbf.Fixed64) this.pos += 8;
else throw new Error('Unimplemented type: ' + type);
},
// === WRITING =================================================================
writeTag: function(tag, type) {
this.writeVarint((tag << 3) | type);
},
realloc: function(min) {
var length = this.length || 16;
while (length < this.pos + min) length *= 2;
if (length !== this.length) {
var buf = new Uint8Array(length);
buf.set(this.buf);
this.buf = buf;
this.length = length;
}
},
finish: function() {
this.length = this.pos;
this.pos = 0;
return this.buf.subarray(0, this.length);
},
writeFixed32: function(val) {
this.realloc(4);
writeInt32(this.buf, val, this.pos);
this.pos += 4;
},
writeSFixed32: function(val) {
this.realloc(4);
writeInt32(this.buf, val, this.pos);
this.pos += 4;
},
writeFixed64: function(val) {
this.realloc(8);
writeInt32(this.buf, val & -1, this.pos);
writeInt32(this.buf, Math.floor(val * SHIFT_RIGHT_32), this.pos + 4);
this.pos += 8;
},
writeSFixed64: function(val) {
this.realloc(8);
writeInt32(this.buf, val & -1, this.pos);
writeInt32(this.buf, Math.floor(val * SHIFT_RIGHT_32), this.pos + 4);
this.pos += 8;
},
writeVarint: function(val) {
val = +val || 0;
if (val > 0xfffffff || val < 0) {
writeBigVarint(val, this);
return;
}
this.realloc(4);
this.buf[this.pos++] = val & 0x7f | (val > 0x7f ? 0x80 : 0); if (val <= 0x7f) return;
this.buf[this.pos++] = ((val >>>= 7) & 0x7f) | (val > 0x7f ? 0x80 : 0); if (val <= 0x7f) return;
this.buf[this.pos++] = ((val >>>= 7) & 0x7f) | (val > 0x7f ? 0x80 : 0); if (val <= 0x7f) return;
this.buf[this.pos++] = (val >>> 7) & 0x7f;
},
writeSVarint: function(val) {
this.writeVarint(val < 0 ? -val * 2 - 1 : val * 2);
},
writeBoolean: function(val) {
this.writeVarint(Boolean(val));
},
writeString: function(str) {
str = String(str);
this.realloc(str.length * 4);
this.pos++; // reserve 1 byte for short string length
var startPos = this.pos;
// write the string directly to the buffer and see how much was written
this.pos = writeUtf8(this.buf, str, this.pos);
var len = this.pos - startPos;
if (len >= 0x80) makeRoomForExtraLength(startPos, len, this);
// finally, write the message length in the reserved place and restore the position
this.pos = startPos - 1;
this.writeVarint(len);
this.pos += len;
},
writeFloat: function(val) {
this.realloc(4);
ieee754.write(this.buf, val, this.pos, true, 23, 4);
this.pos += 4;
},
writeDouble: function(val) {
this.realloc(8);
ieee754.write(this.buf, val, this.pos, true, 52, 8);
this.pos += 8;
},
writeBytes: function(buffer) {
var len = buffer.length;
this.writeVarint(len);
this.realloc(len);
for (var i = 0; i < len; i++) this.buf[this.pos++] = buffer[i];
},
writeRawMessage: function(fn, obj) {
this.pos++; // reserve 1 byte for short message length
// write the message directly to the buffer and see how much was written
var startPos = this.pos;
fn(obj, this);
var len = this.pos - startPos;
if (len >= 0x80) makeRoomForExtraLength(startPos, len, this);
// finally, write the message length in the reserved place and restore the position
this.pos = startPos - 1;
this.writeVarint(len);
this.pos += len;
},
writeMessage: function(tag, fn, obj) {
this.writeTag(tag, Pbf.Bytes);
this.writeRawMessage(fn, obj);
},
writePackedVarint: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedVarint, arr); },
writePackedSVarint: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedSVarint, arr); },
writePackedBoolean: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedBoolean, arr); },
writePackedFloat: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedFloat, arr); },
writePackedDouble: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedDouble, arr); },
writePackedFixed32: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedFixed32, arr); },
writePackedSFixed32: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedSFixed32, arr); },
writePackedFixed64: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedFixed64, arr); },
writePackedSFixed64: function(tag, arr) { if (arr.length) this.writeMessage(tag, writePackedSFixed64, arr); },
writeBytesField: function(tag, buffer) {
this.writeTag(tag, Pbf.Bytes);
this.writeBytes(buffer);
},
writeFixed32Field: function(tag, val) {
this.writeTag(tag, Pbf.Fixed32);
this.writeFixed32(val);
},
writeSFixed32Field: function(tag, val) {
this.writeTag(tag, Pbf.Fixed32);
this.writeSFixed32(val);
},
writeFixed64Field: function(tag, val) {
this.writeTag(tag, Pbf.Fixed64);
this.writeFixed64(val);
},
writeSFixed64Field: function(tag, val) {
this.writeTag(tag, Pbf.Fixed64);
this.writeSFixed64(val);
},
writeVarintField: function(tag, val) {
this.writeTag(tag, Pbf.Varint);
this.writeVarint(val);
},
writeSVarintField: function(tag, val) {
this.writeTag(tag, Pbf.Varint);
this.writeSVarint(val);
},
writeStringField: function(tag, str) {
this.writeTag(tag, Pbf.Bytes);
this.writeString(str);
},
writeFloatField: function(tag, val) {
this.writeTag(tag, Pbf.Fixed32);
this.writeFloat(val);
},
writeDoubleField: function(tag, val) {
this.writeTag(tag, Pbf.Fixed64);
this.writeDouble(val);
},
writeBooleanField: function(tag, val) {
this.writeVarintField(tag, Boolean(val));
}
};
function readVarintRemainder(l, s, p) {
var buf = p.buf,
h, b;
b = buf[p.pos++]; h = (b & 0x70) >> 4; if (b < 0x80) return toNum(l, h, s);
b = buf[p.pos++]; h |= (b & 0x7f) << 3; if (b < 0x80) return toNum(l, h, s);
b = buf[p.pos++]; h |= (b & 0x7f) << 10; if (b < 0x80) return toNum(l, h, s);
b = buf[p.pos++]; h |= (b & 0x7f) << 17; if (b < 0x80) return toNum(l, h, s);
b = buf[p.pos++]; h |= (b & 0x7f) << 24; if (b < 0x80) return toNum(l, h, s);
b = buf[p.pos++]; h |= (b & 0x01) << 31; if (b < 0x80) return toNum(l, h, s);
throw new Error('Expected varint not more than 10 bytes');
}
function readPackedEnd(pbf) {
return pbf.type === Pbf.Bytes ?
pbf.readVarint() + pbf.pos : pbf.pos + 1;
}
function toNum(low, high, isSigned) {
if (isSigned) {
return high * 0x100000000 + (low >>> 0);
}
return ((high >>> 0) * 0x100000000) + (low >>> 0);
}
function writeBigVarint(val, pbf) {
var low, high;
if (val >= 0) {
low = (val % 0x100000000) | 0;
high = (val / 0x100000000) | 0;
} else {
low = ~(-val % 0x100000000);
high = ~(-val / 0x100000000);
if (low ^ 0xffffffff) {
low = (low + 1) | 0;
} else {
low = 0;
high = (high + 1) | 0;
}
}
if (val >= 0x10000000000000000 || val < -0x10000000000000000) {
throw new Error('Given varint doesn\'t fit into 10 bytes');
}
pbf.realloc(10);
writeBigVarintLow(low, high, pbf);
writeBigVarintHigh(high, pbf);
}
function writeBigVarintLow(low, high, pbf) {
pbf.buf[pbf.pos++] = low & 0x7f | 0x80; low >>>= 7;
pbf.buf[pbf.pos++] = low & 0x7f | 0x80; low >>>= 7;
pbf.buf[pbf.pos++] = low & 0x7f | 0x80; low >>>= 7;
pbf.buf[pbf.pos++] = low & 0x7f | 0x80; low >>>= 7;
pbf.buf[pbf.pos] = low & 0x7f;
}
function writeBigVarintHigh(high, pbf) {
var lsb = (high & 0x07) << 4;
pbf.buf[pbf.pos++] |= lsb | ((high >>>= 3) ? 0x80 : 0); if (!high) return;
pbf.buf[pbf.pos++] = high & 0x7f | ((high >>>= 7) ? 0x80 : 0); if (!high) return;
pbf.buf[pbf.pos++] = high & 0x7f | ((high >>>= 7) ? 0x80 : 0); if (!high) return;
pbf.buf[pbf.pos++] = high & 0x7f | ((high >>>= 7) ? 0x80 : 0); if (!high) return;
pbf.buf[pbf.pos++] = high & 0x7f | ((high >>>= 7) ? 0x80 : 0); if (!high) return;
pbf.buf[pbf.pos++] = high & 0x7f;
}
function makeRoomForExtraLength(startPos, len, pbf) {
var extraLen =
len <= 0x3fff ? 1 :
len <= 0x1fffff ? 2 :
len <= 0xfffffff ? 3 : Math.floor(Math.log(len) / (Math.LN2 * 7));
// if 1 byte isn't enough for encoding message length, shift the data to the right
pbf.realloc(extraLen);
for (var i = pbf.pos - 1; i >= startPos; i--) pbf.buf[i + extraLen] = pbf.buf[i];
}
function writePackedVarint(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeVarint(arr[i]); }
function writePackedSVarint(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeSVarint(arr[i]); }
function writePackedFloat(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeFloat(arr[i]); }
function writePackedDouble(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeDouble(arr[i]); }
function writePackedBoolean(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeBoolean(arr[i]); }
function writePackedFixed32(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeFixed32(arr[i]); }
function writePackedSFixed32(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeSFixed32(arr[i]); }
function writePackedFixed64(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeFixed64(arr[i]); }
function writePackedSFixed64(arr, pbf) { for (var i = 0; i < arr.length; i++) pbf.writeSFixed64(arr[i]); }
// Buffer code below from https://github.com/feross/buffer, MIT-licensed
function readUInt32(buf, pos) {
return ((buf[pos]) |
(buf[pos + 1] << 8) |
(buf[pos + 2] << 16)) +
(buf[pos + 3] * 0x1000000);
}
function writeInt32(buf, val, pos) {
buf[pos] = val;
buf[pos + 1] = (val >>> 8);
buf[pos + 2] = (val >>> 16);
buf[pos + 3] = (val >>> 24);
}
function readInt32(buf, pos) {
return ((buf[pos]) |
(buf[pos + 1] << 8) |
(buf[pos + 2] << 16)) +
(buf[pos + 3] << 24);
}
function readUtf8(buf, pos, end) {
var str = '';
var i = pos;
while (i < end) {
var b0 = buf[i];
var c = null; // codepoint
var bytesPerSequence =
b0 > 0xEF ? 4 :
b0 > 0xDF ? 3 :
b0 > 0xBF ? 2 : 1;
if (i + bytesPerSequence > end) break;
var b1, b2, b3;
if (bytesPerSequence === 1) {
if (b0 < 0x80) {
c = b0;
}
} else if (bytesPerSequence === 2) {
b1 = buf[i + 1];
if ((b1 & 0xC0) === 0x80) {
c = (b0 & 0x1F) << 0x6 | (b1 & 0x3F);
if (c <= 0x7F) {
c = null;
}
}
} else if (bytesPerSequence === 3) {
b1 = buf[i + 1];
b2 = buf[i + 2];
if ((b1 & 0xC0) === 0x80 && (b2 & 0xC0) === 0x80) {
c = (b0 & 0xF) << 0xC | (b1 & 0x3F) << 0x6 | (b2 & 0x3F);
if (c <= 0x7FF || (c >= 0xD800 && c <= 0xDFFF)) {
c = null;
}
}
} else if (bytesPerSequence === 4) {
b1 = buf[i + 1];
b2 = buf[i + 2];
b3 = buf[i + 3];
if ((b1 & 0xC0) === 0x80 && (b2 & 0xC0) === 0x80 && (b3 & 0xC0) === 0x80) {
c = (b0 & 0xF) << 0x12 | (b1 & 0x3F) << 0xC | (b2 & 0x3F) << 0x6 | (b3 & 0x3F);
if (c <= 0xFFFF || c >= 0x110000) {
c = null;
}
}
}
if (c === null) {
c = 0xFFFD;
bytesPerSequence = 1;
} else if (c > 0xFFFF) {
c -= 0x10000;
str += String.fromCharCode(c >>> 10 & 0x3FF | 0xD800);
c = 0xDC00 | c & 0x3FF;
}
str += String.fromCharCode(c);
i += bytesPerSequence;
}
return str;
}
function readUtf8TextDecoder(buf, pos, end) {
return utf8TextDecoder.decode(buf.subarray(pos, end));
}
function writeUtf8(buf, str, pos) {
for (var i = 0, c, lead; i < str.length; i++) {
c = str.charCodeAt(i); // code point
if (c > 0xD7FF && c < 0xE000) {
if (lead) {
if (c < 0xDC00) {
buf[pos++] = 0xEF;
buf[pos++] = 0xBF;
buf[pos++] = 0xBD;
lead = c;
continue;
} else {
c = lead - 0xD800 << 10 | c - 0xDC00 | 0x10000;
lead = null;
}
} else {
if (c > 0xDBFF || (i + 1 === str.length)) {
buf[pos++] = 0xEF;
buf[pos++] = 0xBF;
buf[pos++] = 0xBD;
} else {
lead = c;
}
continue;
}
} else if (lead) {
buf[pos++] = 0xEF;
buf[pos++] = 0xBF;
buf[pos++] = 0xBD;
lead = null;
}
if (c < 0x80) {
buf[pos++] = c;
} else {
if (c < 0x800) {
buf[pos++] = c >> 0x6 | 0xC0;
} else {
if (c < 0x10000) {
buf[pos++] = c >> 0xC | 0xE0;
} else {
buf[pos++] = c >> 0x12 | 0xF0;
buf[pos++] = c >> 0xC & 0x3F | 0x80;
}
buf[pos++] = c >> 0x6 & 0x3F | 0x80;
}
buf[pos++] = c & 0x3F | 0x80;
}
}
return pos;
}