| /* |
| * Copyright (C) 2015 Canon Inc. All rights reserved. |
| * Copyright (C) 2015 Igalia. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| // @conditional=ENABLE(READABLE_STREAM_API) |
| // @internal |
| |
| function privateInitializeReadableStreamDefaultReader(stream) |
| { |
| "use strict"; |
| |
| if (!@isReadableStream(stream)) |
| throw new @TypeError("ReadableStreamDefaultReader needs a ReadableStream"); |
| if (@isReadableStreamLocked(stream)) |
| throw new @TypeError("ReadableStream is locked"); |
| |
| this.@readRequests = []; |
| this.@ownerReadableStream = stream; |
| stream.@reader = this; |
| if (stream.@state === @streamReadable) { |
| this.@closedPromiseCapability = @newPromiseCapability(@Promise); |
| return this; |
| } |
| if (stream.@state === @streamClosed) { |
| this.@closedPromiseCapability = { @promise: @Promise.@resolve() }; |
| return this; |
| } |
| @assert(stream.@state === @streamErrored); |
| this.@closedPromiseCapability = { @promise: @Promise.@reject(stream.@storedError) }; |
| |
| return this; |
| } |
| |
| function privateInitializeReadableStreamDefaultController(stream, underlyingSource, size, highWaterMark) |
| { |
| "use strict"; |
| |
| if (!@isReadableStream(stream)) |
| throw new @TypeError("ReadableStreamDefaultController needs a ReadableStream"); |
| |
| // readableStreamController is initialized with null value. |
| if (stream.@readableStreamController !== null) |
| throw new @TypeError("ReadableStream already has a controller"); |
| |
| this.@controlledReadableStream = stream; |
| this.@underlyingSource = underlyingSource; |
| this.@queue = @newQueue(); |
| this.@started = false; |
| this.@closeRequested = false; |
| this.@pullAgain = false; |
| this.@pulling = false; |
| this.@strategy = @validateAndNormalizeQueuingStrategy(size, highWaterMark); |
| |
| const controller = this; |
| const startResult = @promiseInvokeOrNoopNoCatch(underlyingSource, "start", [this]).@then(() => { |
| controller.@started = true; |
| @requestReadableStreamPull(controller); |
| }, (error) => { |
| if (stream.@state === @streamReadable) |
| @readableStreamDefaultControllerError(controller, error); |
| }); |
| |
| this.@pull = function() { |
| "use strict"; |
| |
| const stream = controller.@controlledReadableStream; |
| if (controller.@queue.content.length) { |
| const chunk = @dequeueValue(controller.@queue); |
| if (controller.@closeRequested && controller.@queue.content.length === 0) |
| @closeReadableStream(stream); |
| else |
| @requestReadableStreamPull(controller); |
| return @Promise.@resolve({value: chunk, done: false}); |
| } |
| const pendingPromise = @readableStreamAddReadRequest(stream); |
| @requestReadableStreamPull(controller); |
| return pendingPromise; |
| } |
| |
| return this; |
| } |
| |
| function readableStreamDefaultControllerError(controller, error) |
| { |
| "use strict"; |
| |
| const stream = controller.@controlledReadableStream; |
| @assert(stream.@state === @streamReadable); |
| controller.@queue = @newQueue(); |
| @errorReadableStream(stream, error); |
| } |
| |
| function teeReadableStream(stream, shouldClone) |
| { |
| "use strict"; |
| |
| @assert(@isReadableStream(stream)); |
| @assert(typeof(shouldClone) === "boolean"); |
| |
| const reader = new @ReadableStreamDefaultReader(stream); |
| |
| const teeState = { |
| closedOrErrored: false, |
| canceled1: false, |
| canceled2: false, |
| reason1: @undefined, |
| reason2: @undefined, |
| }; |
| |
| teeState.cancelPromiseCapability = @newPromiseCapability(@InternalPromise); |
| |
| const pullFunction = @teeReadableStreamPullFunction(teeState, reader, shouldClone); |
| |
| const branch1 = new @ReadableStream({ |
| "pull": pullFunction, |
| "cancel": @teeReadableStreamBranch1CancelFunction(teeState, stream) |
| }); |
| const branch2 = new @ReadableStream({ |
| "pull": pullFunction, |
| "cancel": @teeReadableStreamBranch2CancelFunction(teeState, stream) |
| }); |
| |
| reader.@closedPromiseCapability.@promise.@then(@undefined, function(e) { |
| if (teeState.closedOrErrored) |
| return; |
| @readableStreamDefaultControllerError(branch1.@readableStreamController, e); |
| @readableStreamDefaultControllerError(branch2.@readableStreamController, e); |
| teeState.closedOrErrored = true; |
| }); |
| |
| // Additional fields compared to the spec, as they are needed within pull/cancel functions. |
| teeState.branch1 = branch1; |
| teeState.branch2 = branch2; |
| |
| return [branch1, branch2]; |
| } |
| |
| function doStructuredClone(object) |
| { |
| "use strict"; |
| |
| // FIXME: We should implement http://w3c.github.io/html/infrastructure.html#ref-for-structured-clone-4 |
| // Implementation is currently limited to ArrayBuffer/ArrayBufferView to meet Fetch API needs. |
| |
| if (object instanceof @ArrayBuffer) |
| return @structuredCloneArrayBuffer(object); |
| |
| if (@ArrayBuffer.@isView(object)) |
| return @structuredCloneArrayBufferView(object); |
| |
| throw new @TypeError("structuredClone not implemented for: " + object); |
| } |
| |
| function teeReadableStreamPullFunction(teeState, reader, shouldClone) |
| { |
| "use strict"; |
| |
| return function() { |
| @Promise.prototype.@then.@call(@readFromReadableStreamDefaultReader(reader), function(result) { |
| @assert(@isObject(result)); |
| @assert(typeof result.done === "boolean"); |
| if (result.done && !teeState.closedOrErrored) { |
| if (!teeState.canceled1) |
| @readableStreamDefaultControllerClose(teeState.branch1.@readableStreamController); |
| if (!teeState.canceled2) |
| @readableStreamDefaultControllerClose(teeState.branch2.@readableStreamController); |
| teeState.closedOrErrored = true; |
| } |
| if (teeState.closedOrErrored) |
| return; |
| if (!teeState.canceled1) |
| @enqueueInReadableStream(teeState.branch1.@readableStreamController, shouldClone ? @doStructuredClone(result.value) : result.value); |
| if (!teeState.canceled2) |
| @enqueueInReadableStream(teeState.branch2.@readableStreamController, shouldClone ? @doStructuredClone(result.value) : result.value); |
| }); |
| } |
| } |
| |
| function teeReadableStreamBranch1CancelFunction(teeState, stream) |
| { |
| "use strict"; |
| |
| return function(r) { |
| teeState.canceled1 = true; |
| teeState.reason1 = r; |
| if (teeState.canceled2) { |
| @cancelReadableStream(stream, [teeState.reason1, teeState.reason2]).@then( |
| teeState.cancelPromiseCapability.@resolve, |
| teeState.cancelPromiseCapability.@reject); |
| } |
| return teeState.cancelPromiseCapability.@promise; |
| } |
| } |
| |
| function teeReadableStreamBranch2CancelFunction(teeState, stream) |
| { |
| "use strict"; |
| |
| return function(r) { |
| teeState.canceled2 = true; |
| teeState.reason2 = r; |
| if (teeState.canceled1) { |
| @cancelReadableStream(stream, [teeState.reason1, teeState.reason2]).@then( |
| teeState.cancelPromiseCapability.@resolve, |
| teeState.cancelPromiseCapability.@reject); |
| } |
| return teeState.cancelPromiseCapability.@promise; |
| } |
| } |
| |
| function isReadableStream(stream) |
| { |
| "use strict"; |
| |
| // Spec tells to return true only if stream has a readableStreamController internal slot. |
| // However, since it is a private slot, it cannot be checked using hasOwnProperty(). |
| // Therefore, readableStreamController is initialized with null value. |
| return @isObject(stream) && stream.@readableStreamController !== @undefined; |
| } |
| |
| function isReadableStreamDefaultReader(reader) |
| { |
| "use strict"; |
| |
| // Spec tells to return true only if reader has a readRequests internal slot. |
| // However, since it is a private slot, it cannot be checked using hasOwnProperty(). |
| // Since readRequests is initialized with an empty array, the following test is ok. |
| return @isObject(reader) && !!reader.@readRequests; |
| } |
| |
| function isReadableStreamDefaultController(controller) |
| { |
| "use strict"; |
| |
| // Spec tells to return true only if controller has an underlyingSource internal slot. |
| // However, since it is a private slot, it cannot be checked using hasOwnProperty(). |
| // underlyingSource is obtained in ReadableStream constructor: if undefined, it is set |
| // to an empty object. Therefore, following test is ok. |
| return @isObject(controller) && !!controller.@underlyingSource; |
| } |
| |
| function errorReadableStream(stream, error) |
| { |
| "use strict"; |
| |
| @assert(@isReadableStream(stream)); |
| @assert(stream.@state === @streamReadable); |
| stream.@state = @streamErrored; |
| stream.@storedError = error; |
| |
| if (!stream.@reader) |
| return; |
| |
| const reader = stream.@reader; |
| |
| if (@isReadableStreamDefaultReader(reader)) { |
| const requests = reader.@readRequests; |
| for (let index = 0, length = requests.length; index < length; ++index) |
| requests[index].@reject.@call(@undefined, error); |
| reader.@readRequests = []; |
| } else |
| // FIXME: Implement ReadableStreamBYOBReader. |
| throw new @TypeError("Only ReadableStreamDefaultReader is currently supported"); |
| |
| reader.@closedPromiseCapability.@reject.@call(@undefined, error); |
| } |
| |
| function requestReadableStreamPull(controller) |
| { |
| "use strict"; |
| |
| const stream = controller.@controlledReadableStream; |
| |
| if (stream.@state === @streamClosed || stream.@state === @streamErrored) |
| return; |
| if (controller.@closeRequested) |
| return; |
| if (!controller.@started) |
| return; |
| if ((!@isReadableStreamLocked(stream) || !stream.@reader.@readRequests.length) && @readableStreamDefaultControllerGetDesiredSize(controller) <= 0) |
| return; |
| |
| if (controller.@pulling) { |
| controller.@pullAgain = true; |
| return; |
| } |
| |
| controller.@pulling = true; |
| |
| @promiseInvokeOrNoop(controller.@underlyingSource, "pull", [controller]).@then(function() { |
| controller.@pulling = false; |
| if (controller.@pullAgain) { |
| controller.@pullAgain = false; |
| @requestReadableStreamPull(controller); |
| } |
| }, function(error) { |
| if (stream.@state === @streamReadable) |
| @readableStreamDefaultControllerError(controller, error); |
| }); |
| } |
| |
| function isReadableStreamLocked(stream) |
| { |
| "use strict"; |
| |
| @assert(@isReadableStream(stream)); |
| return !!stream.@reader; |
| } |
| |
| function readableStreamDefaultControllerGetDesiredSize(controller) |
| { |
| "use strict"; |
| |
| return controller.@strategy.highWaterMark - controller.@queue.size; |
| } |
| |
| function cancelReadableStream(stream, reason) |
| { |
| "use strict"; |
| |
| stream.@disturbed = true; |
| if (stream.@state === @streamClosed) |
| return @Promise.@resolve(); |
| if (stream.@state === @streamErrored) |
| return @Promise.@reject(stream.@storedError); |
| @closeReadableStream(stream); |
| // FIXME: Fix below, which is a temporary solution to the case where controller is undefined. |
| // This issue is due to the fact that in previous version of the spec, cancel was associated |
| // to underlyingSource, whereas in new version it is associated to controller. As this patch |
| // does not yet fully implement the new version, this solution is used. |
| const controller = stream.@readableStreamController; |
| var underlyingSource = @undefined; |
| if (controller !== @undefined) |
| underlyingSource = controller.@underlyingSource; |
| return @promiseInvokeOrNoop(underlyingSource, "cancel", [reason]).@then(function() { }); |
| } |
| |
| |
| function readableStreamDefaultControllerClose(controller) |
| { |
| "use strict"; |
| |
| const stream = controller.@controlledReadableStream; |
| @assert(!controller.@closeRequested); |
| @assert(stream.@state === @streamReadable); |
| controller.@closeRequested = true; |
| if (controller.@queue.content.length === 0) |
| @closeReadableStream(stream); |
| } |
| |
| function closeReadableStream(stream) |
| { |
| "use strict"; |
| |
| @assert(stream.@state === @streamReadable); |
| stream.@state = @streamClosed; |
| const reader = stream.@reader; |
| |
| if (!reader) |
| return; |
| |
| if (@isReadableStreamDefaultReader(reader)) { |
| const requests = reader.@readRequests; |
| for (let index = 0, length = requests.length; index < length; ++index) |
| requests[index].@resolve.@call(@undefined, {value:@undefined, done: true}); |
| reader.@readRequests = []; |
| } |
| |
| reader.@closedPromiseCapability.@resolve.@call(); |
| } |
| |
| function enqueueInReadableStream(controller, chunk) |
| { |
| "use strict"; |
| |
| const stream = controller.@controlledReadableStream; |
| @assert(!controller.@closeRequested); |
| @assert(stream.@state === @streamReadable); |
| |
| if (@isReadableStreamLocked(stream) && stream.@reader.@readRequests.length) { |
| stream.@reader.@readRequests.@shift().@resolve.@call(@undefined, {value: chunk, done: false}); |
| @requestReadableStreamPull(controller); |
| return; |
| } |
| |
| try { |
| let chunkSize = 1; |
| if (controller.@strategy.size !== @undefined) |
| chunkSize = controller.@strategy.size(chunk); |
| @enqueueValueWithSize(controller.@queue, chunk, chunkSize); |
| } |
| catch(error) { |
| if (stream.@state === @streamReadable) |
| @readableStreamDefaultControllerError(controller, error); |
| throw error; |
| } |
| @requestReadableStreamPull(controller); |
| } |
| |
| function readFromReadableStreamDefaultReader(reader) |
| { |
| "use strict"; |
| |
| const stream = reader.@ownerReadableStream; |
| @assert(!!stream); |
| |
| stream.@disturbed = true; |
| if (stream.@state === @streamClosed) |
| return @Promise.@resolve({value: @undefined, done: true}); |
| if (stream.@state === @streamErrored) |
| return @Promise.@reject(stream.@storedError); |
| @assert(stream.@state === @streamReadable); |
| |
| return stream.@readableStreamController.@pull(); |
| } |
| |
| function readableStreamAddReadRequest(stream) |
| { |
| "use strict"; |
| |
| @assert(@isReadableStreamDefaultReader(stream.@reader)); |
| @assert(stream.@state == @streamReadable); |
| |
| const readRequest = @newPromiseCapability(@Promise); |
| stream.@reader.@readRequests.@push(readRequest); |
| |
| return readRequest.@promise; |
| } |
| |
| function isReadableStreamDisturbed(stream) |
| { |
| "use strict"; |
| |
| @assert(@isReadableStream(stream)); |
| return stream.@disturbed; |
| } |