webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 229 insertions, 0 deletions

diff --git a/Source/WebCore/Modules/streams/ReadableStream.js b/Source/WebCore/Modules/streams/ReadableStream.js
new file mode 100644
index 000000000..faf6c1611
--- /dev/null
+++ b/Source/WebCore/Modules/streams/ReadableStream.js
@@ -0,0 +1,229 @@
+/*
+ * Copyright (C) 2015 Canon Inc.
+ * 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)
+
+function initializeReadableStream(underlyingSource, strategy)
+{
+    "use strict";
+
+     if (underlyingSource === @undefined)
+         underlyingSource = { };
+     if (strategy === @undefined)
+         strategy = { highWaterMark: 1, size: function() { return 1; } };
+
+    if (!@isObject(underlyingSource))
+        @throwTypeError("ReadableStream constructor takes an object as first argument");
+
+    if (strategy !== @undefined && !@isObject(strategy))
+        @throwTypeError("ReadableStream constructor takes an object as second argument, if any");
+
+    this.@state = @streamReadable;
+    this.@reader = @undefined;
+    this.@storedError = @undefined;
+    this.@disturbed = false;
+    // Initialized with null value to enable distinction with undefined case.
+    this.@readableStreamController = null;
+
+    const type = underlyingSource.type;
+    const typeString = @String(type);
+
+    if (typeString === "bytes") {
+        if (strategy.highWaterMark === @undefined)
+            strategy.highWaterMark = 0;
+        // FIXME: When ReadableByteStreamController is no more dependent on a compile flag, specific error handling can be removed.
+        // Constructor is not necessarily available if the byteStream part of Readeable Stream API is not activated. Therefore, a
+        // specific handling of error is done.
+        try {
+            let readableByteStreamControllerConstructor = @ReadableByteStreamController;
+        } catch (e) {
+            @throwTypeError("ReadableByteStreamController is not implemented");
+        }
+        this.@readableStreamController = new @ReadableByteStreamController(this, underlyingSource, strategy.highWaterMark);
+    } else if (type === @undefined) {
+        if (strategy.highWaterMark === @undefined)
+            strategy.highWaterMark = 1;
+        this.@readableStreamController = new @ReadableStreamDefaultController(this, underlyingSource, strategy.size, strategy.highWaterMark);
+    } else
+        @throwRangeError("Invalid type for underlying source");
+
+    return this;
+}
+
+function cancel(reason)
+{
+    "use strict";
+
+    if (!@isReadableStream(this))
+        return @Promise.@reject(@makeThisTypeError("ReadableStream", "cancel"));
+
+    if (@isReadableStreamLocked(this))
+        return @Promise.@reject(new @TypeError("ReadableStream is locked"));
+
+    return @readableStreamCancel(this, reason);
+}
+
+function getReader(options)
+{
+    "use strict";
+
+    if (!@isReadableStream(this))
+        throw @makeThisTypeError("ReadableStream", "getReader");
+
+    if (options === @undefined)
+         options = { };
+
+    if (options.mode === 'byob') {
+        // FIXME: Update once ReadableByteStreamContoller and ReadableStreamBYOBReader are implemented.
+        @throwTypeError("ReadableStreamBYOBReader is not implemented");
+    }
+
+    if (options.mode === @undefined)
+        return new @ReadableStreamDefaultReader(this);
+
+    @throwRangeError("Invalid mode is specified");
+}
+
+function pipeThrough(streams, options)
+{
+    "use strict";
+
+    const writable = streams.writable;
+    const readable = streams.readable;
+    this.pipeTo(writable, options);
+    return readable;
+}
+
+function pipeTo(destination)
+{
+    "use strict";
+
+    // FIXME: https://bugs.webkit.org/show_bug.cgi?id=159869.
+    // Built-in generator should be able to parse function signature to compute the function length correctly.
+    const options = arguments[1];
+
+    // FIXME: rewrite pipeTo so as to require to have 'this' as a ReadableStream and destination be a WritableStream.
+    // See https://github.com/whatwg/streams/issues/407.
+    // We should shield the pipeTo implementation at the same time.
+
+    const preventClose = @isObject(options) && !!options.preventClose;
+    const preventAbort = @isObject(options) && !!options.preventAbort;
+    const preventCancel = @isObject(options) && !!options.preventCancel;
+
+    const source = this;
+
+    let reader;
+    let lastRead;
+    let lastWrite;
+    let closedPurposefully = false;
+    let promiseCapability;
+
+    function doPipe() {
+        lastRead = reader.read();
+        @Promise.prototype.@then.@call(@Promise.all([lastRead, destination.ready]), function([{ value, done }]) {
+            if (done)
+                closeDestination();
+            else if (destination.state === "writable") {
+                lastWrite = destination.write(value);
+                doPipe();
+            }
+        }, function(e) {
+            throw e;
+        });
+    }
+
+    function cancelSource(reason) {
+        if (!preventCancel) {
+            reader.cancel(reason);
+            reader.releaseLock();
+            promiseCapability.@reject.@call(@undefined, reason);
+        } else {
+            @Promise.prototype.@then.@call(lastRead, function() {
+                reader.releaseLock();
+                promiseCapability.@reject.@call(@undefined, reason);
+            });
+        }
+    }
+
+    function closeDestination() {
+        reader.releaseLock();
+
+        const destinationState = destination.state;
+        if (!preventClose && (destinationState === "waiting" || destinationState === "writable")) {
+            closedPurposefully = true;
+            @Promise.prototype.@then.@call(destination.close(), promiseCapability.@resolve, promiseCapability.@reject);
+        } else if (lastWrite !== @undefined)
+            @Promise.prototype.@then.@call(lastWrite, promiseCapability.@resolve, promiseCapability.@reject);
+        else
+            promiseCapability.@resolve.@call();
+
+    }
+
+    function abortDestination(reason) {
+        reader.releaseLock();
+
+        if (!preventAbort)
+            destination.abort(reason);
+        promiseCapability.@reject.@call(@undefined, reason);
+    }
+
+    promiseCapability = @newPromiseCapability(@Promise);
+
+    reader = source.getReader();
+
+    @Promise.prototype.@then.@call(reader.closed, @undefined, abortDestination);
+    @Promise.prototype.@then.@call(destination.closed,
+        function() {
+            if (!closedPurposefully)
+                cancelSource(new @TypeError('destination is closing or closed and cannot be piped to anymore'));
+        },
+        cancelSource
+    );
+
+    doPipe();
+
+    return promiseCapability.@promise;
+}
+
+function tee()
+{
+    "use strict";
+
+    if (!@isReadableStream(this))
+        throw @makeThisTypeError("ReadableStream", "tee");
+
+    return @readableStreamTee(this, false);
+}
+
+function locked()
+{
+    "use strict";
+
+    if (!@isReadableStream(this))
+        throw @makeGetterTypeError("ReadableStream", "locked");
+
+    return @isReadableStreamLocked(this);
+}