etcher-sdk
Version:
55 lines • 2.41 kB
JavaScript
;
/*
* 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.ProgressSparseTransformStream = exports.SparseTransformStream = void 0;
const stream_1 = require("stream");
const aligned_lockable_buffer_1 = require("../aligned-lockable-buffer");
const progress_1 = require("../source-destination/progress");
const utils_1 = require("../utils");
class SparseTransformStream extends stream_1.Transform {
constructor({ blocks, chunkSize, alignment, numBuffers = 2, }) {
super({ objectMode: true, highWaterMark: numBuffers - 1 });
this.position = 0;
this.bytesWritten = 0;
this.blocks = blocks;
this.alignedReadableState = new aligned_lockable_buffer_1.AlignedReadableState(chunkSize, alignment, numBuffers);
}
async __transform(chunk) {
this.position = chunk.position;
// This will fail if a chunk buffer is larger than chunkSize passed to the constructor
let buffer = this.alignedReadableState.getCurrentBuffer();
const unlock = await buffer.lock();
try {
if (chunk.buffer.length < buffer.length) {
buffer = buffer.slice(0, chunk.buffer.length);
}
chunk.buffer.copy(buffer);
}
finally {
unlock();
}
this.push({ position: chunk.position, buffer });
this.bytesWritten += chunk.buffer.length;
this.position += chunk.buffer.length;
}
_transform(chunk, _encoding, callback) {
(0, utils_1.asCallback)(this.__transform(chunk), callback);
}
}
exports.SparseTransformStream = SparseTransformStream;
exports.ProgressSparseTransformStream = (0, progress_1.makeClassEmitProgressEvents)(SparseTransformStream, 'bytesWritten', 'position');
//# sourceMappingURL=sparse-transform-stream.js.map