modules/mediasource/WebKitMediaSource.cpp

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#include "config.h"
#include "modules/mediasource/WebKitMediaSource.h"

#include "bindings/v8/ExceptionState.h"
#include "bindings/v8/ExceptionStatePlaceholder.h"
#include "core/dom/ExceptionCode.h"
#include "core/html/TimeRanges.h"
#include "modules/mediasource/MediaSourceRegistry.h"
#include "platform/ContentType.h"
#include "platform/MIMETypeRegistry.h"
#include "public/platform/WebSourceBuffer.h"
#include "wtf/Uint8Array.h"

using blink::WebSourceBuffer;

namespace WebCore {

PassRefPtr<WebKitMediaSource> WebKitMediaSource::create(ExecutionContext* context)
{
    RefPtr<WebKitMediaSource> mediaSource(adoptRef(new WebKitMediaSource(context)));
    mediaSource->suspendIfNeeded();
    return mediaSource.release();
}

WebKitMediaSource::WebKitMediaSource(ExecutionContext* context)
    : MediaSourceBase(context)
{
    ScriptWrappable::init(this);
    m_sourceBuffers = WebKitSourceBufferList::create(executionContext(), asyncEventQueue());
    m_activeSourceBuffers = WebKitSourceBufferList::create(executionContext(), asyncEventQueue());
}

WebKitSourceBufferList* WebKitMediaSource::sourceBuffers()
{
    return m_sourceBuffers.get();
}

WebKitSourceBufferList* WebKitMediaSource::activeSourceBuffers()
{
    // FIXME(91649): support track selection
    return m_activeSourceBuffers.get();
}

WebKitSourceBuffer* WebKitMediaSource::addSourceBuffer(const String& type, ExceptionState& exceptionState)
{
    // 3.1 http://dvcs.w3.org/hg/html-media/raw-file/tip/media-source/media-source.html#dom-addsourcebuffer
    // 1. If type is null or an empty then throw an InvalidAccessError exception and
    // abort these steps.
    if (type.isNull() || type.isEmpty()) {
        exceptionState.throwUninformativeAndGenericDOMException(InvalidAccessError);
        return 0;
    }

    // 2. If type contains a MIME type that is not supported ..., then throw a
    // NotSupportedError exception and abort these steps.
    if (!isTypeSupported(type)) {
        exceptionState.throwUninformativeAndGenericDOMException(NotSupportedError);
        return 0;
    }

    // 4. If the readyState attribute is not in the "open" state then throw an
    // InvalidStateError exception and abort these steps.
    if (!isOpen()) {
        exceptionState.throwUninformativeAndGenericDOMException(InvalidStateError);
        return 0;
    }

    // 5. Create a new SourceBuffer object and associated resources.
    ContentType contentType(type);
    Vector<String> codecs = contentType.codecs();
    OwnPtr<WebSourceBuffer> webSourceBuffer = createWebSourceBuffer(contentType.type(), codecs, exceptionState);
    if (!webSourceBuffer)
        return 0;

    RefPtr<WebKitSourceBuffer> buffer = WebKitSourceBuffer::create(webSourceBuffer.release(), this);
    // 6. Add the new object to sourceBuffers and fire a addsourcebuffer on that object.
    m_sourceBuffers->add(buffer);
    m_activeSourceBuffers->add(buffer);
    // 7. Return the new object to the caller.
    return buffer.get();
}

void WebKitMediaSource::removeSourceBuffer(WebKitSourceBuffer* buffer, ExceptionState& exceptionState)
{
    // 3.1 http://dvcs.w3.org/hg/html-media/raw-file/tip/media-source/media-source.html#dom-removesourcebuffer
    // 1. If sourceBuffer is null then throw an InvalidAccessError exception and
    // abort these steps.
    if (!buffer) {
        exceptionState.throwUninformativeAndGenericDOMException(InvalidAccessError);
        return;
    }

    // 2. If sourceBuffers is empty then throw an InvalidStateError exception and
    // abort these steps.
    if (isClosed() || !m_sourceBuffers->length()) {
        exceptionState.throwUninformativeAndGenericDOMException(InvalidStateError);
        return;
    }

    // 3. If sourceBuffer specifies an object that is not in sourceBuffers then
    // throw a NotFoundError exception and abort these steps.
    // 6. Remove sourceBuffer from sourceBuffers and fire a removesourcebuffer event
    // on that object.
    if (!m_sourceBuffers->remove(buffer)) {
        exceptionState.throwUninformativeAndGenericDOMException(NotFoundError);
        return;
    }

    // 7. Destroy all resources for sourceBuffer.
    m_activeSourceBuffers->remove(buffer);

    // 4. Remove track information from audioTracks, videoTracks, and textTracks for all tracks
    // associated with sourceBuffer and fire a simple event named change on the modified lists.
    // FIXME(91649): support track selection

    // 5. If sourceBuffer is in activeSourceBuffers, then remove it from that list and fire a
    // removesourcebuffer event on that object.
    // FIXME(91649): support track selection
}

void WebKitMediaSource::onReadyStateChange(const AtomicString& oldState, const AtomicString& newState)
{
    if (isClosed()) {
        m_sourceBuffers->clear();
        m_activeSourceBuffers->clear();
        scheduleEvent(EventTypeNames::webkitsourceclose);
        return;
    }

    if (oldState == openKeyword() && newState == endedKeyword()) {
        scheduleEvent(EventTypeNames::webkitsourceended);
        return;
    }

    if (isOpen()) {
        scheduleEvent(EventTypeNames::webkitsourceopen);
        return;
    }
}

Vector<RefPtr<TimeRanges> > WebKitMediaSource::activeRanges() const
{
    Vector<RefPtr<TimeRanges> > activeRanges(m_activeSourceBuffers->length());
    for (size_t i = 0; i < m_activeSourceBuffers->length(); ++i)
        activeRanges[i] = m_activeSourceBuffers->item(i)->buffered(ASSERT_NO_EXCEPTION);

    return activeRanges;
}

bool WebKitMediaSource::isTypeSupported(const String& type)
{
    // Section 2.1 isTypeSupported() method steps.
    // https://dvcs.w3.org/hg/html-media/raw-file/tip/media-source/media-source.html#widl-MediaSource-isTypeSupported-boolean-DOMString-type
    // 1. If type is an empty string, then return false.
    if (type.isNull() || type.isEmpty())
        return false;

    ContentType contentType(type);
    String codecs = contentType.parameter("codecs");

    // 2. If type does not contain a valid MIME type string, then return false.
    if (contentType.type().isEmpty())
        return false;

    // 3. If type contains a media type or media subtype that the MediaSource does not support, then return false.
    // 4. If type contains at a codec that the MediaSource does not support, then return false.
    // 5. If the MediaSource does not support the specified combination of media type, media subtype, and codecs then return false.
    // 6. Return true.
    return MIMETypeRegistry::isSupportedMediaSourceMIMEType(contentType.type(), codecs);
}

const AtomicString& WebKitMediaSource::interfaceName() const
{
    return EventTargetNames::WebKitMediaSource;
}

} // namespace WebCore