etcher-sdk
Version:
88 lines • 3.56 kB
JavaScript
"use strict";
/*
* Copyright 2018 balena.io
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.ProgressBlockWriteStream = exports.BlockWriteStream = void 0;
const direct_io_1 = require("@ronomon/direct-io");
const _debug = require("debug");
const stream_1 = require("stream");
const constants_1 = require("./constants");
const errors_1 = require("./errors");
const progress_1 = require("./source-destination/progress");
const utils_1 = require("./utils");
const debug = _debug('etcher:writer:block-write-stream');
class BlockWriteStream extends stream_1.Writable {
constructor({ destination, highWaterMark, delayFirstBuffer = false, maxRetries = 5, startOffset = 0, }) {
super({ objectMode: true, highWaterMark });
this.bytesWritten = 0;
this.position = 0;
this.startOffset = 0;
this.destination = destination;
this.delayFirstBuffer = delayFirstBuffer;
this.maxRetries = maxRetries;
this.startOffset = startOffset;
}
async writeBuffer(buffer, position) {
await (0, errors_1.retryOnTransientError)(async () => {
await this.destination.write(buffer, 0, buffer.length, position + this.startOffset);
}, this.maxRetries, constants_1.RETRY_BASE_TIMEOUT);
}
async __write(buffer) {
const unlock = await buffer.rlock();
debug('_write', buffer.length, this.position, this.bytesWritten);
try {
// Keep the first buffer in memory and write it once the rest has been written.
// This is to prevent Windows from mounting the device while we flash it.
if (this.delayFirstBuffer && this.firstBuffer === undefined) {
this.firstBuffer = (0, direct_io_1.getAlignedBuffer)(buffer.length, buffer.alignment);
buffer.copy(this.firstBuffer);
}
else {
await this.writeBuffer(buffer, this.position);
this.bytesWritten += buffer.length;
}
this.position += buffer.length;
}
finally {
unlock();
}
}
_write(buffer, _encoding, callback) {
(0, utils_1.asCallback)(this.__write(buffer), callback);
}
async __final() {
debug('_final');
if (this.firstBuffer) {
try {
await this.writeBuffer(this.firstBuffer, 0);
this.bytesWritten += this.firstBuffer.length;
}
catch (error) {
this.destroy();
throw error;
}
}
}
/**
* @summary Write buffered data before a stream ends, called by stream internals
*/
_final(callback) {
(0, utils_1.asCallback)(this.__final(), callback);
}
}
exports.BlockWriteStream = BlockWriteStream;
exports.ProgressBlockWriteStream = (0, progress_1.makeClassEmitProgressEvents)(BlockWriteStream, 'bytesWritten', 'bytesWritten');
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