Source/WebCore/loader/SubresourceLoader.h

/*
 * Copyright (C) 2005-2025 Apple Inc. All rights reserved.
 *
 * 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.
 * 3.  Neither the name of Apple Inc. ("Apple") 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 APPLE 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 APPLE OR 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.
 */

#pragma once

#include "CachedResourceLoader.h"
#include "FrameLoaderTypes.h"
#include "ResourceLoader.h"
#include <wtf/CompletionHandler.h>
#include <wtf/WeakPtr.h>
#include <wtf/text/WTFString.h>
 
namespace WebCore {

class CachedResource;
class CachedResourceLoader;
class NetworkLoadMetrics;
class ResourceRequest;
class SecurityOrigin;

class SubresourceLoader final : public ResourceLoader {
public:
    WEBCORE_EXPORT static void create(LocalFrame&, CachedResource&, ResourceRequest&&, const ResourceLoaderOptions&, CompletionHandler<void(RefPtr<SubresourceLoader>&&)>&&);

    virtual ~SubresourceLoader();

    void cancelIfNotFinishing();
    bool isSubresourceLoader() const final;
    CachedResource* cachedResource() const final { return m_resource.get(); };
    CachedResourceHandle<CachedResource> protectedCachedResource() const { return cachedResource(); }

    WEBCORE_EXPORT const HTTPHeaderMap* originalHeaders() const;

    const SecurityOrigin* origin() const { return m_origin.get(); }
    SecurityOrigin* origin() { return m_origin.get(); }
    RefPtr<SecurityOrigin> protectedOrigin() const;
#if PLATFORM(IOS_FAMILY)
    void startLoading() final;

    // FIXME: What is an "iOS" original request? Why is it necessary?
    const ResourceRequest& iOSOriginalRequest() const final { return m_iOSOriginalRequest; }
#endif

    unsigned redirectCount() const { return m_redirectCount; }

    void markInAsyncResponsePolicyCheck() { m_inAsyncResponsePolicyCheck = true; }
    void didReceiveResponsePolicy();

    void clearRequestCountTracker() { m_requestCountTracker = std::nullopt; }
    void resetRequestCountTracker(CachedResourceLoader& loader, const CachedResource& resource) { m_requestCountTracker = RequestCountTracker { loader, resource }; }

    void willSendRequestInternal(ResourceRequest&&, const ResourceResponse& redirectResponse, CompletionHandler<void(ResourceRequest&&)>&&) final;
    void didSendData(unsigned long long bytesSent, unsigned long long totalBytesToBeSent) final;
    void didReceiveResponse(ResourceResponse&&, CompletionHandler<void()>&& policyCompletionHandler) final;
    void didReceiveBuffer(const FragmentedSharedBuffer&, long long encodedDataLength, DataPayloadType) final;
    void didFinishLoading(const NetworkLoadMetrics&) final;
    void didFail(const ResourceError&) final;
    void willCancel(const ResourceError&) final;
    void didCancel(LoadWillContinueInAnotherProcess) final;

private:
    SubresourceLoader(LocalFrame&, CachedResource&, const ResourceLoaderOptions&);

    void init(ResourceRequest&&, CompletionHandler<void(bool)>&&) final;
    
    void updateReferrerPolicy(const String&);

#if PLATFORM(COCOA)
    void willCacheResponseAsync(ResourceHandle*, NSCachedURLResponse*, CompletionHandler<void(NSCachedURLResponse *)>&&) final;
#endif

    void releaseResources() final;

    bool responseHasHTTPStatusCodeError() const;
    Expected<void, String> checkResponseCrossOriginAccessControl(const ResourceResponse&);
    Expected<void, String> checkRedirectionCrossOriginAccessControl(const ResourceRequest& previousRequest, const ResourceResponse&, ResourceRequest& newRequest);

    void didReceiveDataOrBuffer(const FragmentedSharedBuffer&, long long encodedDataLength, DataPayloadType);

    void notifyDone(LoadCompletionType);

    void reportResourceTiming(const NetworkLoadMetrics&);

#if USE(QUICK_LOOK)
    bool shouldCreatePreviewLoaderForResponse(const ResourceResponse&) const;
    void didReceivePreviewResponse(ResourceResponse&&) final;
#endif

    enum SubresourceLoaderState {
        Uninitialized,
        Initialized,
        Finishing,
#if PLATFORM(IOS_FAMILY)
        CancelledWhileInitializing
#endif
    };

    class RequestCountTracker {
        WTF_DEPRECATED_MAKE_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(RequestCountTracker, Loader);
    public:
        RequestCountTracker(CachedResourceLoader&, const CachedResource&);
        RequestCountTracker(RequestCountTracker&&);
        RequestCountTracker& operator=(RequestCountTracker&&);
        ~RequestCountTracker();
    private:
        WeakPtr<CachedResourceLoader> m_cachedResourceLoader;
        WeakPtr<CachedResource> m_resource;
    };

#if PLATFORM(IOS_FAMILY)
    ResourceRequest m_iOSOriginalRequest;
#endif
    WeakPtr<CachedResource> m_resource;
    SubresourceLoaderState m_state;
    std::optional<RequestCountTracker> m_requestCountTracker;
    RefPtr<SecurityOrigin> m_origin;
    CompletionHandler<void()> m_policyForResponseCompletionHandler;
    ResourceResponse m_previousPartResponse;
    unsigned m_redirectCount { 0 };
    bool m_loadingMultipartContent { false };
    bool m_inAsyncResponsePolicyCheck { false };
    FetchMetadataSite m_site { FetchMetadataSite::SameOrigin };
};

}

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::SubresourceLoader)
static bool isType(const WebCore::ResourceLoader& loader) { return loader.isSubresourceLoader(); }
SPECIALIZE_TYPE_TRAITS_END()