ReadableJSStream.h   [plain text]

/*
 * Copyright (C) 2O15 Canon Inc. 2015
 * Copyright (C) 2015 Igalia S.L. 2015
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted, provided that the following conditions
 * are required to be 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.
 * 3.  Neither the name of Canon Inc. nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY CANON INC. AND ITS CONTRIBUTORS "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 CANON INC. AND ITS 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.
 */

#ifndef ReadableJSStream_h
#define ReadableJSStream_h

#if ENABLE(STREAMS_API)

#include "ReadableStream.h"
#include <heap/Strong.h>
#include <heap/StrongInlines.h>
#include <runtime/JSCJSValue.h>
#include <runtime/PrivateName.h>
#include <wtf/Deque.h>
#include <wtf/Ref.h>

namespace JSC {
class JSFunction;
class JSPromise;
}
    
namespace WebCore {

class JSDOMGlobalObject;
class ReadableStreamController;

typedef int ExceptionCode;

class ReadableJSStream: public ReadableStream {
public:
    static RefPtr<ReadableJSStream> create(JSC::ExecState&, JSC::JSValue, const Dictionary&);

    JSC::JSValue jsController(JSC::ExecState&, JSDOMGlobalObject*);
    void close(ExceptionCode&);

    void storeError(JSC::ExecState&, JSC::JSValue);
    JSC::JSValue error() override { return m_error.get(); }

    void enqueue(JSC::ExecState&, JSC::JSValue);
    void error(JSC::ExecState&, JSC::JSValue, ExceptionCode&);

    double desiredSize() const { return m_highWaterMark - m_totalQueueSize; }

private:
    ReadableJSStream(JSC::ExecState&, JSC::JSObject*, double, JSC::JSFunction*);

    void doStart(JSC::ExecState&);

    JSC::JSPromise* invoke(JSC::ExecState&, const char*, JSC::JSValue parameter);
    void storeException(JSC::ExecState&);

    virtual bool hasEnoughValues() const override { return desiredSize() <= 0; }
    virtual bool hasValue() const override;
    virtual JSC::JSValue read() override;
    virtual bool doPull() override;
    virtual bool doCancel(JSC::JSValue) override;

    JSDOMGlobalObject* globalObject();

    double retrieveChunkSize(JSC::ExecState&, JSC::JSValue);

    std::unique_ptr<ReadableStreamController> m_controller;
    // FIXME: we should consider not using JSC::Strong, see https://bugs.webkit.org/show_bug.cgi?id=146278
    JSC::Strong<JSC::Unknown> m_error;
    JSC::Strong<JSC::JSFunction> m_errorFunction;
    JSC::Strong<JSC::JSObject> m_source;

    struct Chunk {
        JSC::Strong<JSC::Unknown> value;
        double size;
    };
    Deque<Chunk> m_chunkQueue;

    double m_totalQueueSize { 0 };
    double m_highWaterMark;
    JSC::Strong<JSC::JSFunction> m_sizeFunction;
};

} // namespace WebCore

#endif // ENABLE(STREAMS_API)

#endif // ReadableJSStream_h