511 lines
17 KiB
JavaScript
511 lines
17 KiB
JavaScript
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// Protocol Buffers - Google's data interchange format
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// Copyright 2008 Google Inc. All rights reserved.
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// https://developers.google.com/protocol-buffers/
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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// * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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/**
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* @fileoverview BinaryEncode defines methods for encoding Javascript values
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* into arrays of bytes compatible with the Protocol Buffer wire format.
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*
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* @author aappleby@google.com (Austin Appleby)
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*/
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goog.provide('jspb.BinaryEncoder');
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goog.require('goog.asserts');
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goog.require('jspb.BinaryConstants');
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goog.require('jspb.utils');
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/**
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* BinaryEncoder implements encoders for all the wire types specified in
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* https://developers.google.com/protocol-buffers/docs/encoding.
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*
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* @constructor
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* @struct
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*/
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jspb.BinaryEncoder = function() {
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/** @private {!Array<number>} */
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this.buffer_ = [];
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};
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/**
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* @return {number}
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*/
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jspb.BinaryEncoder.prototype.length = function() {
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return this.buffer_.length;
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};
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/**
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* @return {!Array<number>}
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*/
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jspb.BinaryEncoder.prototype.end = function() {
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var buffer = this.buffer_;
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this.buffer_ = [];
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return buffer;
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};
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/**
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* Encodes a 64-bit integer in 32:32 split representation into its wire-format
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* varint representation and stores it in the buffer.
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* @param {number} lowBits The low 32 bits of the int.
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* @param {number} highBits The high 32 bits of the int.
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*/
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jspb.BinaryEncoder.prototype.writeSplitVarint64 = function(lowBits, highBits) {
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goog.asserts.assert(lowBits == Math.floor(lowBits));
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goog.asserts.assert(highBits == Math.floor(highBits));
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goog.asserts.assert((lowBits >= 0) &&
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(lowBits < jspb.BinaryConstants.TWO_TO_32));
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goog.asserts.assert((highBits >= 0) &&
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(highBits < jspb.BinaryConstants.TWO_TO_32));
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// Break the binary representation into chunks of 7 bits, set the 8th bit
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// in each chunk if it's not the final chunk, and append to the result.
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while (highBits > 0 || lowBits > 127) {
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this.buffer_.push((lowBits & 0x7f) | 0x80);
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lowBits = ((lowBits >>> 7) | (highBits << 25)) >>> 0;
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highBits = highBits >>> 7;
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}
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this.buffer_.push(lowBits);
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};
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/**
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* Encodes a 64-bit integer in 32:32 split representation into its wire-format
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* fixed representation and stores it in the buffer.
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* @param {number} lowBits The low 32 bits of the int.
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* @param {number} highBits The high 32 bits of the int.
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*/
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jspb.BinaryEncoder.prototype.writeSplitFixed64 = function(lowBits, highBits) {
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goog.asserts.assert(lowBits == Math.floor(lowBits));
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goog.asserts.assert(highBits == Math.floor(highBits));
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goog.asserts.assert((lowBits >= 0) &&
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(lowBits < jspb.BinaryConstants.TWO_TO_32));
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goog.asserts.assert((highBits >= 0) &&
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(highBits < jspb.BinaryConstants.TWO_TO_32));
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this.writeUint32(lowBits);
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this.writeUint32(highBits);
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};
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/**
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* Encodes a 32-bit unsigned integer into its wire-format varint representation
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* and stores it in the buffer.
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* @param {number} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeUnsignedVarint32 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= 0) &&
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(value < jspb.BinaryConstants.TWO_TO_32));
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while (value > 127) {
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this.buffer_.push((value & 0x7f) | 0x80);
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value = value >>> 7;
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}
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this.buffer_.push(value);
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};
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/**
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* Encodes a 32-bit signed integer into its wire-format varint representation
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* and stores it in the buffer.
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* @param {number} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeSignedVarint32 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_31) &&
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(value < jspb.BinaryConstants.TWO_TO_31));
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// Use the unsigned version if the value is not negative.
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if (value >= 0) {
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this.writeUnsignedVarint32(value);
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return;
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}
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// Write nine bytes with a _signed_ right shift so we preserve the sign bit.
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for (var i = 0; i < 9; i++) {
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this.buffer_.push((value & 0x7f) | 0x80);
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value = value >> 7;
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}
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// The above loop writes out 63 bits, so the last byte is always the sign bit
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// which is always set for negative numbers.
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this.buffer_.push(1);
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};
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/**
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* Encodes a 64-bit unsigned integer into its wire-format varint representation
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* and stores it in the buffer. Integers that are not representable in 64 bits
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* will be truncated.
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* @param {number} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeUnsignedVarint64 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= 0) &&
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(value < jspb.BinaryConstants.TWO_TO_64));
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jspb.utils.splitInt64(value);
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this.writeSplitVarint64(jspb.utils.split64Low,
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jspb.utils.split64High);
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};
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/**
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* Encodes a 64-bit signed integer into its wire-format varint representation
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* and stores it in the buffer. Integers that are not representable in 64 bits
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* will be truncated.
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* @param {number} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeSignedVarint64 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_63) &&
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(value < jspb.BinaryConstants.TWO_TO_63));
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jspb.utils.splitInt64(value);
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this.writeSplitVarint64(jspb.utils.split64Low,
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jspb.utils.split64High);
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};
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/**
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* Encodes a JavaScript integer into its wire-format, zigzag-encoded varint
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* representation and stores it in the buffer.
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* @param {number} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeZigzagVarint32 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_31) &&
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(value < jspb.BinaryConstants.TWO_TO_31));
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this.writeUnsignedVarint32(((value << 1) ^ (value >> 31)) >>> 0);
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};
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/**
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* Encodes a JavaScript integer into its wire-format, zigzag-encoded varint
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* representation and stores it in the buffer. Integers not representable in 64
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* bits will be truncated.
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* @param {number} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeZigzagVarint64 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_63) &&
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(value < jspb.BinaryConstants.TWO_TO_63));
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jspb.utils.splitZigzag64(value);
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this.writeSplitVarint64(jspb.utils.split64Low,
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jspb.utils.split64High);
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};
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/**
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* Encodes a JavaScript decimal string into its wire-format, zigzag-encoded
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* varint representation and stores it in the buffer. Integers not representable
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* in 64 bits will be truncated.
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* @param {string} value The integer to convert.
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*/
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jspb.BinaryEncoder.prototype.writeZigzagVarint64String = function(value) {
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this.writeZigzagVarintHash64(jspb.utils.decimalStringToHash64(value));
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};
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/**
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* Writes a 64-bit hash string (8 characters @ 8 bits of data each) to the
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* buffer as a zigzag varint.
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* @param {string} hash The hash to write.
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*/
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jspb.BinaryEncoder.prototype.writeZigzagVarintHash64 = function(hash) {
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var self = this;
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jspb.utils.splitHash64(hash);
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jspb.utils.toZigzag64(
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jspb.utils.split64Low, jspb.utils.split64High, function(lo, hi) {
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self.writeSplitVarint64(lo >>> 0, hi >>> 0);
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});
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};
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/**
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* Writes an 8-bit unsigned integer to the buffer. Numbers outside the range
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* [0,2^8) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeUint8 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= 0) && (value < 256));
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this.buffer_.push((value >>> 0) & 0xFF);
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};
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/**
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* Writes a 16-bit unsigned integer to the buffer. Numbers outside the
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* range [0,2^16) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeUint16 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= 0) && (value < 65536));
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this.buffer_.push((value >>> 0) & 0xFF);
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this.buffer_.push((value >>> 8) & 0xFF);
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};
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/**
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* Writes a 32-bit unsigned integer to the buffer. Numbers outside the
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* range [0,2^32) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeUint32 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= 0) &&
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(value < jspb.BinaryConstants.TWO_TO_32));
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this.buffer_.push((value >>> 0) & 0xFF);
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this.buffer_.push((value >>> 8) & 0xFF);
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this.buffer_.push((value >>> 16) & 0xFF);
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this.buffer_.push((value >>> 24) & 0xFF);
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};
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/**
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* Writes a 64-bit unsigned integer to the buffer. Numbers outside the
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* range [0,2^64) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeUint64 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= 0) &&
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(value < jspb.BinaryConstants.TWO_TO_64));
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jspb.utils.splitUint64(value);
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this.writeUint32(jspb.utils.split64Low);
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this.writeUint32(jspb.utils.split64High);
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};
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/**
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* Writes an 8-bit integer to the buffer. Numbers outside the range
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* [-2^7,2^7) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeInt8 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -128) && (value < 128));
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this.buffer_.push((value >>> 0) & 0xFF);
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};
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/**
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* Writes a 16-bit integer to the buffer. Numbers outside the range
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* [-2^15,2^15) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeInt16 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -32768) && (value < 32768));
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this.buffer_.push((value >>> 0) & 0xFF);
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this.buffer_.push((value >>> 8) & 0xFF);
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};
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/**
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* Writes a 32-bit integer to the buffer. Numbers outside the range
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* [-2^31,2^31) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeInt32 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_31) &&
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(value < jspb.BinaryConstants.TWO_TO_31));
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this.buffer_.push((value >>> 0) & 0xFF);
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this.buffer_.push((value >>> 8) & 0xFF);
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this.buffer_.push((value >>> 16) & 0xFF);
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this.buffer_.push((value >>> 24) & 0xFF);
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};
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/**
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* Writes a 64-bit integer to the buffer. Numbers outside the range
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* [-2^63,2^63) will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeInt64 = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_63) &&
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(value < jspb.BinaryConstants.TWO_TO_63));
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jspb.utils.splitInt64(value);
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this.writeSplitFixed64(jspb.utils.split64Low, jspb.utils.split64High);
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};
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/**
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* Writes a 64-bit integer decimal strings to the buffer. Numbers outside the
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* range [-2^63,2^63) will be truncated.
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* @param {string} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeInt64String = function(value) {
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goog.asserts.assert(value == Math.floor(value));
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goog.asserts.assert((+value >= -jspb.BinaryConstants.TWO_TO_63) &&
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(+value < jspb.BinaryConstants.TWO_TO_63));
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jspb.utils.splitHash64(jspb.utils.decimalStringToHash64(value));
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this.writeSplitFixed64(jspb.utils.split64Low, jspb.utils.split64High);
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};
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/**
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* Writes a single-precision floating point value to the buffer. Numbers
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* requiring more than 32 bits of precision will be truncated.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeFloat = function(value) {
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goog.asserts.assert(
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value === Infinity || value === -Infinity || isNaN(value) ||
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((value >= -jspb.BinaryConstants.FLOAT32_MAX) &&
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(value <= jspb.BinaryConstants.FLOAT32_MAX)));
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jspb.utils.splitFloat32(value);
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this.writeUint32(jspb.utils.split64Low);
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};
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/**
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* Writes a double-precision floating point value to the buffer. As this is
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* the native format used by JavaScript, no precision will be lost.
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* @param {number} value The value to write.
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*/
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jspb.BinaryEncoder.prototype.writeDouble = function(value) {
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goog.asserts.assert(
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value === Infinity || value === -Infinity || isNaN(value) ||
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((value >= -jspb.BinaryConstants.FLOAT64_MAX) &&
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(value <= jspb.BinaryConstants.FLOAT64_MAX)));
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jspb.utils.splitFloat64(value);
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this.writeUint32(jspb.utils.split64Low);
|
||
|
this.writeUint32(jspb.utils.split64High);
|
||
|
};
|
||
|
|
||
|
|
||
|
/**
|
||
|
* Writes a boolean value to the buffer as a varint. We allow numbers as input
|
||
|
* because the JSPB code generator uses 0/1 instead of true/false to save space
|
||
|
* in the string representation of the proto.
|
||
|
* @param {boolean|number} value The value to write.
|
||
|
*/
|
||
|
jspb.BinaryEncoder.prototype.writeBool = function(value) {
|
||
|
goog.asserts.assert(typeof value === 'boolean' || typeof value === 'number');
|
||
|
this.buffer_.push(value ? 1 : 0);
|
||
|
};
|
||
|
|
||
|
|
||
|
/**
|
||
|
* Writes an enum value to the buffer as a varint.
|
||
|
* @param {number} value The value to write.
|
||
|
*/
|
||
|
jspb.BinaryEncoder.prototype.writeEnum = function(value) {
|
||
|
goog.asserts.assert(value == Math.floor(value));
|
||
|
goog.asserts.assert((value >= -jspb.BinaryConstants.TWO_TO_31) &&
|
||
|
(value < jspb.BinaryConstants.TWO_TO_31));
|
||
|
this.writeSignedVarint32(value);
|
||
|
};
|
||
|
|
||
|
|
||
|
/**
|
||
|
* Writes an arbitrary byte array to the buffer.
|
||
|
* @param {!Uint8Array} bytes The array of bytes to write.
|
||
|
*/
|
||
|
jspb.BinaryEncoder.prototype.writeBytes = function(bytes) {
|
||
|
this.buffer_.push.apply(this.buffer_, bytes);
|
||
|
};
|
||
|
|
||
|
|
||
|
/**
|
||
|
* Writes a 64-bit hash string (8 characters @ 8 bits of data each) to the
|
||
|
* buffer as a varint.
|
||
|
* @param {string} hash The hash to write.
|
||
|
*/
|
||
|
jspb.BinaryEncoder.prototype.writeVarintHash64 = function(hash) {
|
||
|
jspb.utils.splitHash64(hash);
|
||
|
this.writeSplitVarint64(jspb.utils.split64Low,
|
||
|
jspb.utils.split64High);
|
||
|
};
|
||
|
|
||
|
|
||
|
/**
|
||
|
* Writes a 64-bit hash string (8 characters @ 8 bits of data each) to the
|
||
|
* buffer as a fixed64.
|
||
|
* @param {string} hash The hash to write.
|
||
|
*/
|
||
|
jspb.BinaryEncoder.prototype.writeFixedHash64 = function(hash) {
|
||
|
jspb.utils.splitHash64(hash);
|
||
|
this.writeUint32(jspb.utils.split64Low);
|
||
|
this.writeUint32(jspb.utils.split64High);
|
||
|
};
|
||
|
|
||
|
|
||
|
/**
|
||
|
* Writes a UTF16 Javascript string to the buffer encoded as UTF8.
|
||
|
* TODO(aappleby): Add support for surrogate pairs, reject unpaired surrogates.
|
||
|
* @param {string} value The string to write.
|
||
|
* @return {number} The number of bytes used to encode the string.
|
||
|
*/
|
||
|
jspb.BinaryEncoder.prototype.writeString = function(value) {
|
||
|
var oldLength = this.buffer_.length;
|
||
|
|
||
|
for (var i = 0; i < value.length; i++) {
|
||
|
|
||
|
var c = value.charCodeAt(i);
|
||
|
|
||
|
if (c < 128) {
|
||
|
this.buffer_.push(c);
|
||
|
} else if (c < 2048) {
|
||
|
this.buffer_.push((c >> 6) | 192);
|
||
|
this.buffer_.push((c & 63) | 128);
|
||
|
} else if (c < 65536) {
|
||
|
// Look for surrogates
|
||
|
if (c >= 0xD800 && c <= 0xDBFF && i + 1 < value.length) {
|
||
|
var second = value.charCodeAt(i + 1);
|
||
|
if (second >= 0xDC00 && second <= 0xDFFF) { // low surrogate
|
||
|
// http://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
|
||
|
c = (c - 0xD800) * 0x400 + second - 0xDC00 + 0x10000;
|
||
|
|
||
|
this.buffer_.push((c >> 18) | 240);
|
||
|
this.buffer_.push(((c >> 12) & 63 ) | 128);
|
||
|
this.buffer_.push(((c >> 6) & 63) | 128);
|
||
|
this.buffer_.push((c & 63) | 128);
|
||
|
i++;
|
||
|
}
|
||
|
}
|
||
|
else {
|
||
|
this.buffer_.push((c >> 12) | 224);
|
||
|
this.buffer_.push(((c >> 6) & 63) | 128);
|
||
|
this.buffer_.push((c & 63) | 128);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
var length = this.buffer_.length - oldLength;
|
||
|
return length;
|
||
|
};
|