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- // Copyright 2014 The Chromium Authors. All rights reserved.
- // Use of this source code is governed by a BSD-style license that can be
- // found in the LICENSE file.
-
- define('data_receiver', [
- 'device/serial/data_stream.mojom',
- 'device/serial/data_stream_serialization.mojom',
- 'mojo/public/js/core',
- 'mojo/public/js/router',
- ], function(dataStream, serialization, core, router) {
- /**
- * @module data_receiver
- */
-
- /**
- * A pending receive operation.
- * @constructor
- * @alias module:data_receiver~PendingReceive
- * @private
- */
- function PendingReceive() {
- /**
- * The promise that will be resolved or rejected when this receive completes
- * or fails, respectively.
- * @type {!Promise.<ArrayBuffer>}
- * @private
- */
- this.promise_ = new Promise(function(resolve, reject) {
- /**
- * The callback to call with the data received on success.
- * @type {Function}
- * @private
- */
- this.dataCallback_ = resolve;
- /**
- * The callback to call with the error on failure.
- * @type {Function}
- * @private
- */
- this.errorCallback_ = reject;
- }.bind(this));
- }
-
- /**
- * Returns the promise that will be resolved when this operation completes or
- * rejected if an error occurs.
- * @return {Promise.<ArrayBuffer>} A promise to the data received.
- */
- PendingReceive.prototype.getPromise = function() {
- return this.promise_;
- };
-
- /**
- * Dispatches received data to the promise returned by
- * [getPromise]{@link module:data_receiver.PendingReceive#getPromise}.
- * @param {!ArrayBuffer} data The data to dispatch.
- */
- PendingReceive.prototype.dispatchData = function(data) {
- this.dataCallback_(data);
- };
-
- /**
- * Dispatches an error if the offset of the error has been reached.
- * @param {!PendingReceiveError} error The error to dispatch.
- * @param {number} bytesReceived The number of bytes that have been received.
- */
- PendingReceive.prototype.dispatchError = function(error) {
- if (error.queuePosition > 0)
- return false;
-
- var e = new Error();
- e.error = error.error;
- this.errorCallback_(e);
- return true;
- };
-
- /**
- * Unconditionally dispatches an error.
- * @param {number} error The error to dispatch.
- */
- PendingReceive.prototype.dispatchFatalError = function(error) {
- var e = new Error();
- e.error = error;
- this.errorCallback_(e);
- };
-
- /**
- * A DataReceiver that receives data from a DataSource.
- * @param {!MojoHandle} handle The handle to the DataSource.
- * @param {number} bufferSize How large a buffer to use.
- * @param {number} fatalErrorValue The receive error value to report in the
- * event of a fatal error.
- * @constructor
- * @alias module:data_receiver.DataReceiver
- */
- function DataReceiver(handle, bufferSize, fatalErrorValue) {
- this.init_(handle, fatalErrorValue, 0, null, [], false);
- this.source_.init(bufferSize);
- }
-
- DataReceiver.prototype =
- $Object.create(dataStream.DataSourceClient.stubClass.prototype);
-
- /**
- * Closes this DataReceiver.
- */
- DataReceiver.prototype.close = function() {
- if (this.shutDown_)
- return;
- this.shutDown_ = true;
- this.router_.close();
- if (this.receive_) {
- this.receive_.dispatchFatalError(this.fatalErrorValue_);
- this.receive_ = null;
- }
- };
-
- /**
- * Initialize this DataReceiver.
- * @param {!MojoHandle} source A handle to the DataSource
- * @param {number} fatalErrorValue The error to dispatch in the event of a
- * fatal error.
- * @param {number} bytesReceived The number of bytes already received.
- * @param {PendingReceiveError} pendingError The pending error if there is
- * one.
- * @param {!Array.<!ArrayBuffer>} pendingData Data received from the
- * DataSource not yet requested by the client.
- * @param {boolean} paused Whether the DataSource is paused.
- * @private
- */
- DataReceiver.prototype.init_ = function(source,
- fatalErrorValue,
- bytesReceived,
- pendingError,
- pendingData,
- paused) {
- /**
- * The [Router]{@link module:mojo/public/js/router.Router} for the
- * connection to the DataSource.
- * @private
- */
- this.router_ = new router.Router(source);
- /**
- * The connection to the DataSource.
- * @private
- */
- this.source_ = new dataStream.DataSource.proxyClass(this.router_);
- this.router_.setIncomingReceiver(this);
- /**
- * The current receive operation.
- * @type {module:data_receiver~PendingReceive}
- * @private
- */
- this.receive_ = null;
- /**
- * The error to be dispatched in the event of a fatal error.
- * @const {number}
- * @private
- */
- this.fatalErrorValue_ = fatalErrorValue;
- /**
- * The pending error if there is one.
- * @type {PendingReceiveError}
- * @private
- */
- this.pendingError_ = pendingError;
- /**
- * Whether the DataSource is paused.
- * @type {boolean}
- * @private
- */
- this.paused_ = paused;
- /**
- * A queue of data that has been received from the DataSource, but not
- * consumed by the client.
- * @type {module:data_receiver~PendingData[]}
- * @private
- */
- this.pendingDataBuffers_ = pendingData;
- /**
- * Whether this DataReceiver has shut down.
- * @type {boolean}
- * @private
- */
- this.shutDown_ = false;
- };
-
- /**
- * Serializes this DataReceiver.
- * This will cancel a receive if one is in progress.
- * @return {!Promise.<SerializedDataReceiver>} A promise that will resolve to
- * the serialization of this DataReceiver. If this DataReceiver has shut
- * down, the promise will resolve to null.
- */
- DataReceiver.prototype.serialize = function() {
- if (this.shutDown_)
- return Promise.resolve(null);
-
- if (this.receive_) {
- this.receive_.dispatchFatalError(this.fatalErrorValue_);
- this.receive_ = null;
- }
- var serialized = new serialization.SerializedDataReceiver();
- serialized.source = this.router_.connector_.handle_;
- serialized.fatal_error_value = this.fatalErrorValue_;
- serialized.paused = this.paused_;
- serialized.pending_error = this.pendingError_;
- serialized.pending_data = [];
- $Array.forEach(this.pendingDataBuffers_, function(buffer) {
- serialized.pending_data.push(new Uint8Array(buffer));
- });
- this.router_.connector_.handle_ = null;
- this.router_.close();
- this.shutDown_ = true;
- return Promise.resolve(serialized);
- };
-
- /**
- * Deserializes a SerializedDataReceiver.
- * @param {SerializedDataReceiver} serialized The serialized DataReceiver.
- * @return {!DataReceiver} The deserialized DataReceiver.
- */
- DataReceiver.deserialize = function(serialized) {
- var receiver = $Object.create(DataReceiver.prototype);
- receiver.deserialize_(serialized);
- return receiver;
- };
-
- /**
- * Deserializes a SerializedDataReceiver into this DataReceiver.
- * @param {SerializedDataReceiver} serialized The serialized DataReceiver.
- * @private
- */
- DataReceiver.prototype.deserialize_ = function(serialized) {
- if (!serialized) {
- this.shutDown_ = true;
- return;
- }
- var pendingData = [];
- $Array.forEach(serialized.pending_data, function(data) {
- var buffer = new Uint8Array(data.length);
- buffer.set(data);
- pendingData.push(buffer.buffer);
- });
- this.init_(serialized.source,
- serialized.fatal_error_value,
- serialized.bytes_received,
- serialized.pending_error,
- pendingData,
- serialized.paused);
- };
-
- /**
- * Receive data from the DataSource.
- * @return {Promise.<ArrayBuffer>} A promise to the received data. If an error
- * occurs, the promise will reject with an Error object with a property
- * error containing the error code.
- * @throws Will throw if this has encountered a fatal error or another receive
- * is in progress.
- */
- DataReceiver.prototype.receive = function() {
- if (this.shutDown_)
- throw new Error('DataReceiver has been closed');
- if (this.receive_)
- throw new Error('Receive already in progress.');
- var receive = new PendingReceive();
- var promise = receive.getPromise();
- if (this.pendingError_ &&
- receive.dispatchError(this.pendingError_)) {
- this.pendingError_ = null;
- this.paused_ = true;
- return promise;
- }
- if (this.paused_) {
- this.source_.resume();
- this.paused_ = false;
- }
- this.receive_ = receive;
- this.dispatchData_();
- return promise;
- };
-
- DataReceiver.prototype.dispatchData_ = function() {
- if (!this.receive_) {
- this.close();
- return;
- }
- if (this.pendingDataBuffers_.length) {
- this.receive_.dispatchData(this.pendingDataBuffers_[0]);
- this.source_.reportBytesReceived(this.pendingDataBuffers_[0].byteLength);
- this.receive_ = null;
- this.pendingDataBuffers_.shift();
- if (this.pendingError_)
- this.pendingError_.queuePosition--;
- }
- };
-
- /**
- * Invoked by the DataSource when an error is encountered.
- * @param {number} offset The location at which the error occurred.
- * @param {number} error The error that occurred.
- * @private
- */
- DataReceiver.prototype.onError = function(error) {
- if (this.shutDown_)
- return;
-
- var pendingError = new serialization.PendingReceiveError();
- pendingError.error = error;
- pendingError.queuePosition = this.pendingDataBuffers_.length;
- if (this.receive_ && this.receive_.dispatchError(pendingError)) {
- this.receive_ = null;
- this.paused_ = true;
- return;
- }
- this.pendingError_ = pendingError;
- };
-
- DataReceiver.prototype.onData = function(data) {
- var buffer = new ArrayBuffer(data.length);
- var uintView = new Uint8Array(buffer);
- uintView.set(data);
- this.pendingDataBuffers_.push(buffer);
- if (this.receive_)
- this.dispatchData_();
- };
-
- return {DataReceiver: DataReceiver};
- });
-