third_party/WebKit/Source/core/loader/WorkerThreadableLoader.h

/*
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 * modification, are permitted provided that the following conditions are
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#ifndef WorkerThreadableLoader_h
#define WorkerThreadableLoader_h

#include "core/loader/ThreadableLoader.h"
#include "core/loader/ThreadableLoaderClient.h"
#include "core/loader/ThreadableLoaderClientWrapper.h"
#include "platform/heap/Handle.h"
#include "platform/weborigin/Referrer.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/PassRefPtr.h"
#include "wtf/RefPtr.h"
#include "wtf/Threading.h"
#include "wtf/text/WTFString.h"

namespace blink {

class ResourceError;
class ResourceRequest;
class WorkerGlobalScope;
class WorkerLoaderProxy;
struct CrossThreadResourceRequestData;

class WorkerThreadableLoader final : public ThreadableLoader, private ThreadableLoaderClientWrapper::ResourceTimingClient {
    USING_FAST_MALLOC(WorkerThreadableLoader);
public:
    static void loadResourceSynchronously(WorkerGlobalScope&, const ResourceRequest&, ThreadableLoaderClient&, const ThreadableLoaderOptions&, const ResourceLoaderOptions&);
    static PassRefPtr<WorkerThreadableLoader> create(WorkerGlobalScope& workerGlobalScope, PassRefPtr<ThreadableLoaderClientWrapper> clientWrapper, PassOwnPtr<ThreadableLoaderClient> clientBridge, const ResourceRequest& request, const ThreadableLoaderOptions& options, const ResourceLoaderOptions& resourceLoaderOptions)
    {
        return adoptRef(new WorkerThreadableLoader(workerGlobalScope, clientWrapper, clientBridge, request, options, resourceLoaderOptions));
    }

    ~WorkerThreadableLoader() override;

    void overrideTimeout(unsigned long timeout) override;

    void cancel() override;

private:
    // Creates a loader on the main thread and bridges communication between
    // the main thread and the worker context's thread where WorkerThreadableLoader runs.
    //
    // Regarding the bridge and lifetimes of items used in callbacks, there are a few cases:
    //
    // all cases. All tasks posted from the worker context's thread are ok because
    //    the last task posted always is "mainThreadDestroy", so MainThreadBridge is
    //    around for all tasks that use it on the main thread.
    //
    // case 1. worker.terminate is called.
    //    In this case, no more tasks are posted from the worker object's thread to the worker
    //    context's thread -- WorkerGlobalScopeProxy implementation enforces this.
    //
    // case 2. xhr gets aborted and the worker context continues running.
    //    The ThreadableLoaderClientWrapper has the underlying client cleared, so no more calls
    //    go through it.  All tasks posted from the worker object's thread to the worker context's
    //    thread do "ThreadableLoaderClientWrapper::ref" (automatically inside of the cross thread copy
    //    done in createCrossThreadTask), so the ThreadableLoaderClientWrapper instance is there until all
    //    tasks are executed.
    class MainThreadBridge final : public ThreadableLoaderClient {
    public:
        // All executed on the worker context's thread.
        MainThreadBridge(PassRefPtr<ThreadableLoaderClientWrapper>, PassOwnPtr<ThreadableLoaderClient>, PassRefPtr<WorkerLoaderProxy>, const ResourceRequest&, const ThreadableLoaderOptions&, const ResourceLoaderOptions&, const ReferrerPolicy, const String& outgoingReferrer);
        void overrideTimeout(unsigned long timeoutMilliseconds);
        void cancel();
        void destroy();

    private:
        // Executed on the worker context's thread.
        void clearClientWrapper();

        // All executed on the main thread.
        void mainThreadDestroy(ExecutionContext*);
        ~MainThreadBridge() override;

        void mainThreadCreateLoader(PassOwnPtr<CrossThreadResourceRequestData>, ThreadableLoaderOptions, ResourceLoaderOptions, const ReferrerPolicy, const String& outgoingReferrer, ExecutionContext*);
        void mainThreadOverrideTimeout(unsigned long timeoutMilliseconds, ExecutionContext*);
        void mainThreadCancel(ExecutionContext*);
        void didSendData(unsigned long long bytesSent, unsigned long long totalBytesToBeSent) override;
        void didReceiveResponse(unsigned long identifier, const ResourceResponse&, PassOwnPtr<WebDataConsumerHandle>) override;
        void didReceiveData(const char*, unsigned dataLength) override;
        void didDownloadData(int dataLength) override;
        void didReceiveCachedMetadata(const char*, int dataLength) override;
        void didFinishLoading(unsigned long identifier, double finishTime) override;
        void didFail(const ResourceError&) override;
        void didFailAccessControlCheck(const ResourceError&) override;
        void didFailRedirectCheck() override;
        void didReceiveResourceTiming(const ResourceTimingInfo&) override;

        // Only to be used on the main thread.
        RefPtr<ThreadableLoader> m_mainThreadLoader;
        OwnPtr<ThreadableLoaderClient> m_clientBridge;

        // ThreadableLoaderClientWrapper is to be used on the worker context thread.
        // The ref counting is done on either thread.
        RefPtr<ThreadableLoaderClientWrapper> m_workerClientWrapper;

        // Used on the worker context thread.
        RefPtr<WorkerLoaderProxy> m_loaderProxy;
    };

    WorkerThreadableLoader(WorkerGlobalScope&, PassRefPtr<ThreadableLoaderClientWrapper>, PassOwnPtr<ThreadableLoaderClient>, const ResourceRequest&, const ThreadableLoaderOptions&, const ResourceLoaderOptions&);

    void didReceiveResourceTiming(const ResourceTimingInfo&) override;

    RefPtrWillBePersistent<WorkerGlobalScope> m_workerGlobalScope;
    RefPtr<ThreadableLoaderClientWrapper> m_workerClientWrapper;
    MainThreadBridge& m_bridge;
};

} // namespace blink

#endif // WorkerThreadableLoader_h