/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsBaseChannel_h__

#define nsBaseChannel_h__

#include "mozilla/net/NeckoTargetHolder.h"

#include "nsString.h"

#include "nsAutoPtr.h"

#include "nsCOMPtr.h"

#include "nsHashPropertyBag.h"

#include "nsInputStreamPump.h"

#include "nsIChannel.h"

#include "nsIURI.h"

#include "nsILoadGroup.h"

#include "nsILoadInfo.h"

#include "nsIStreamListener.h"

#include "nsIInterfaceRequestor.h"

#include "nsIProgressEventSink.h"

#include "nsITransport.h"

#include "nsIAsyncVerifyRedirectCallback.h"

#include "nsIThreadRetargetableRequest.h"

#include "nsIThreadRetargetableStreamListener.h"

#include "PrivateBrowsingChannel.h"

#include "nsThreadUtils.h"

class nsIInputStream;

//-----------------------------------------------------------------------------

// nsBaseChannel is designed to be subclassed.  The subclass is responsible for

// implementing the OpenContentStream method, which will be called by the

// nsIChannel::AsyncOpen and nsIChannel::Open implementations.

//

// nsBaseChannel implements nsIInterfaceRequestor to provide a convenient way

// for subclasses to query both the nsIChannel::notificationCallbacks and

// nsILoadGroup::notificationCallbacks for supported interfaces.

//

// nsBaseChannel implements nsITransportEventSink to support progress & status

// notifications generated by the transport layer.

class nsBaseChannel : public nsHashPropertyBag

                    , public nsIChannel

                    , public nsIThreadRetargetableRequest

                    , public nsIInterfaceRequestor

                    , public nsITransportEventSink

                    , public nsIAsyncVerifyRedirectCallback

                    , public mozilla::net::PrivateBrowsingChannel<nsBaseChannel>

                    , public mozilla::net::NeckoTargetHolder

                    , protected nsIStreamListener

                    , protected nsIThreadRetargetableStreamListener

{

public:

  NS_DECL_ISUPPORTS_INHERITED

  NS_DECL_NSIREQUEST

  NS_DECL_NSICHANNEL

  NS_DECL_NSIINTERFACEREQUESTOR

  NS_DECL_NSITRANSPORTEVENTSINK

  NS_DECL_NSIASYNCVERIFYREDIRECTCALLBACK

  NS_DECL_NSITHREADRETARGETABLEREQUEST

  NS_DECL_NSITHREADRETARGETABLESTREAMLISTENER

  nsBaseChannel();

  // This method must be called to initialize the basechannel instance.

  nsresult Init() {

    return NS_OK;

  }

protected:

  // -----------------------------------------------

  // Methods to be implemented by the derived class:

  virtual ~nsBaseChannel();

private:

  // Implemented by subclass to supply data stream.  The parameter, async, is

  // true when called from nsIChannel::AsyncOpen and false otherwise.  When

  // async is true, the resulting stream will be used with a nsIInputStreamPump

  // instance.  This means that if it is a non-blocking stream that supports

  // nsIAsyncInputStream that it will be read entirely on the main application

  // thread, and its AsyncWait method will be called whenever ReadSegments

  // returns NS_BASE_STREAM_WOULD_BLOCK.  Otherwise, if the stream is blocking,

  // then it will be read on one of the background I/O threads, and it does not

  // need to implement ReadSegments.  If async is false, this method may return

  // NS_ERROR_NOT_IMPLEMENTED to cause the basechannel to implement Open in

  // terms of AsyncOpen (see NS_ImplementChannelOpen).

  // A callee is allowed to return an nsIChannel instead of an nsIInputStream.

  // That case will be treated as a redirect to the new channel.  By default

  // *channel will be set to null by the caller, so callees who don't want to

  // return one an just not touch it.

  virtual nsresult OpenContentStream(bool async, nsIInputStream **stream,

                                     nsIChannel** channel) = 0;

  // Implemented by subclass to begin pumping data for an async channel, in

  // lieu of returning a stream. If implemented, OpenContentStream will never

  // be called for async channels. If not implemented, AsyncOpen2 will fall

  // back to OpenContentStream.

  //

  // On success, the callee must begin pumping data to the stream listener,

  // and at some point call OnStartRequest followed by OnStopRequest.

  // Additionally, it may provide a request object which may be used to

  // suspend, resume, and cancel the underlying request.

  virtual nsresult BeginAsyncRead(nsIStreamListener* listener, nsIRequest** request) {

    return NS_ERROR_NOT_IMPLEMENTED;

  }

  // The basechannel calls this method from its OnTransportStatus method to

  // determine whether to call nsIProgressEventSink::OnStatus in addition to

  // nsIProgressEventSink::OnProgress.  This method may be overriden by the

  // subclass to enable nsIProgressEventSink::OnStatus events.  If this method

  // returns true, then the statusArg out param specifies the "statusArg" value

  // to pass to the OnStatus method.  By default, OnStatus messages are

  // suppressed.  The status parameter passed to this method is the status value

  // from the OnTransportStatus method.

  virtual bool GetStatusArg(nsresult status, nsString &statusArg) {

    return false;

  }

  // Called when the callbacks available to this channel may have changed.

  virtual void OnCallbacksChanged() {

  }

  // Called when our channel is done, to allow subclasses to drop resources.

  virtual void OnChannelDone() {

  }

public:

  // ----------------------------------------------

  // Methods provided for use by the derived class:

  // Redirect to another channel.  This method takes care of notifying

  // observers of this redirect as well as of opening the new channel, if asked

  // to do so.  It also cancels |this| with the status code

  // NS_BINDING_REDIRECTED.  A failure return from this method means that the

  // redirect could not be performed (no channel was opened; this channel

  // wasn't canceled.)  The redirectFlags parameter consists of the flag values

  // defined on nsIChannelEventSink.

  nsresult Redirect(nsIChannel *newChannel, uint32_t redirectFlags,

                    bool openNewChannel);

  // Tests whether a type hint was set. Subclasses can use this to decide

  // whether to call SetContentType.

  // NOTE: This is only reliable if the subclass didn't itself call

  // SetContentType, and should also not be called after OpenContentStream.

  bool HasContentTypeHint() const;

  // The URI member should be initialized before the channel is used, and then

  // it should never be changed again until the channel is destroyed.

  nsIURI *URI() {

    return mURI;

  }

  void SetURI(nsIURI *uri) {

    NS_ASSERTION(uri, "must specify a non-null URI");

    NS_ASSERTION(!mURI, "must not modify URI");

    NS_ASSERTION(!mOriginalURI, "how did that get set so early?");

    mURI = uri;

    mOriginalURI = uri;

  }

  nsIURI *OriginalURI() {

    return mOriginalURI;

  }

  // The security info is a property of the transport-layer, which should be

  // assigned by the subclass.

  nsISupports *SecurityInfo() {

    return mSecurityInfo;

  }

  void SetSecurityInfo(nsISupports *info) {

    mSecurityInfo = info;

  }

  // Test the load flags

  bool HasLoadFlag(uint32_t flag) {

    return (mLoadFlags & flag) != 0;

  }

  // This is a short-cut to calling nsIRequest::IsPending()

  virtual bool Pending() const {

    return mPumpingData || mWaitingOnAsyncRedirect;

 }

  // Helper function for querying the channel's notification callbacks.

  template <class T> void GetCallback(nsCOMPtr<T> &result) {

    GetInterface(NS_GET_TEMPLATE_IID(T), getter_AddRefs(result));

  }

Unexecuted instantiation: void nsBaseChannel::GetCallback<nsIProgressEventSink>(nsCOMPtr<nsIProgressEventSink>&)

Unexecuted instantiation: void nsBaseChannel::GetCallback<nsITabChild>(nsCOMPtr<nsITabChild>&)

Unexecuted instantiation: void nsBaseChannel::GetCallback<nsIPrompt>(nsCOMPtr<nsIPrompt>&)

Unexecuted instantiation: void nsBaseChannel::GetCallback<nsIFTPEventSink>(nsCOMPtr<nsIFTPEventSink>&)

Unexecuted instantiation: void nsBaseChannel::GetCallback<nsIFTPChannelParentInternal>(nsCOMPtr<nsIFTPChannelParentInternal>&)

  // Helper function for calling QueryInterface on this.

  nsQueryInterface do_QueryInterface() {

    return nsQueryInterface(static_cast<nsIChannel *>(this));

  }

  // MSVC needs this:

  nsQueryInterface do_QueryInterface(nsISupports *obj) {

    return nsQueryInterface(obj);

  }

  // If a subclass does not want to feed transport-layer progress events to the

  // base channel via nsITransportEventSink, then it may set this flag to cause

  // the base channel to synthesize progress events when it receives data from

  // the content stream.  By default, progress events are not synthesized.

  void EnableSynthesizedProgressEvents(bool enable) {

    mSynthProgressEvents = enable;

  }

  // Some subclasses may wish to manually insert a stream listener between this

  // and the channel's listener.  The following methods make that possible.

  void SetStreamListener(nsIStreamListener *listener) {

    mListener = listener;

  }

  nsIStreamListener *StreamListener() {

    return mListener;

  }

  // Pushes a new stream converter in front of the channel's stream listener.

  // The fromType and toType values are passed to nsIStreamConverterService's

  // AsyncConvertData method.  If invalidatesContentLength is true, then the

  // channel's content-length property will be assigned a value of -1.  This is

  // necessary when the converter changes the length of the resulting data

  // stream, which is almost always the case for a "stream converter" ;-)

  // This function optionally returns a reference to the new converter.

  nsresult PushStreamConverter(const char *fromType, const char *toType,

                               bool invalidatesContentLength = true,

                               nsIStreamListener **converter = nullptr);

protected:

  void DisallowThreadRetargeting() {

    mAllowThreadRetargeting = false;

  }

  virtual void SetupNeckoTarget();

private:

  NS_DECL_NSISTREAMLISTENER

  NS_DECL_NSIREQUESTOBSERVER

  // Called to setup mPump and call AsyncRead on it.

  nsresult BeginPumpingData();

  // Called when the callbacks available to this channel may have changed.

  void CallbacksChanged() {

    mProgressSink = nullptr;

    mQueriedProgressSink = false;

    OnCallbacksChanged();

  }

  // Called when our channel is done.  This should drop no-longer-needed pointers.

  void ChannelDone() {

      mListener = nullptr;

      mListenerContext = nullptr;

      OnChannelDone();

  }

  // Handle an async redirect callback.  This will only be called if we

  // returned success from AsyncOpen while posting a redirect runnable.

  void HandleAsyncRedirect(nsIChannel* newChannel);

  void ContinueHandleAsyncRedirect(nsresult result);

  nsresult ContinueRedirect();

  // start URI classifier if requested

  void ClassifyURI();

  class RedirectRunnable : public mozilla::Runnable

  {

  public:

    RedirectRunnable(nsBaseChannel* chan, nsIChannel* newChannel)

      : mozilla::Runnable("nsBaseChannel::RedirectRunnable")

      , mChannel(chan)

      , mNewChannel(newChannel)

    {

      MOZ_ASSERT(newChannel, "Must have channel to redirect to");

    }

    NS_IMETHOD Run() override

    {

      mChannel->HandleAsyncRedirect(mNewChannel);

      return NS_OK;

    }

  private:

    RefPtr<nsBaseChannel> mChannel;

    nsCOMPtr<nsIChannel> mNewChannel;

  };

  friend class RedirectRunnable;

  RefPtr<nsInputStreamPump>         mPump;

  RefPtr<nsIRequest>                  mRequest;

  bool                                mPumpingData;

  nsCOMPtr<nsIProgressEventSink>      mProgressSink;

  nsCOMPtr<nsIURI>                    mOriginalURI;

  nsCOMPtr<nsISupports>               mOwner;

  nsCOMPtr<nsISupports>               mSecurityInfo;

  nsCOMPtr<nsIChannel>                mRedirectChannel;

  nsCString                           mContentType;

  nsCString                           mContentCharset;

  uint32_t                            mLoadFlags;

  bool                                mQueriedProgressSink;

  bool                                mSynthProgressEvents;

  bool                                mAllowThreadRetargeting;

  bool                                mWaitingOnAsyncRedirect;

  bool                                mOpenRedirectChannel;

  uint32_t                            mRedirectFlags;

protected:

  nsCOMPtr<nsIURI>                    mURI;

  nsCOMPtr<nsILoadGroup>              mLoadGroup;

  nsCOMPtr<nsILoadInfo>               mLoadInfo;

  nsCOMPtr<nsIInterfaceRequestor>     mCallbacks;

  nsCOMPtr<nsIStreamListener>         mListener;

  nsCOMPtr<nsISupports>               mListenerContext;

  nsresult                            mStatus;

  uint32_t                            mContentDispositionHint;

  nsAutoPtr<nsString>                 mContentDispositionFilename;

  int64_t                             mContentLength;

  bool                                mWasOpened;

  friend class mozilla::net::PrivateBrowsingChannel<nsBaseChannel>;

};

#endif // !nsBaseChannel_h__