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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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
#ifndef nsFrameMessageManager_h__
#define nsFrameMessageManager_h__
#include <string.h>
#include <cstdint>
#include <utility>
#include "ErrorList.h"
#include "js/TypeDecls.h"
#include "js/Value.h"
#include "js/experimental/JSStencil.h"
#include "mozilla/AlreadyAddRefed.h"
#include "mozilla/RefPtr.h"
#include "mozilla/Services.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/TypedEnumBits.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/dom/ipc/StructuredCloneData.h"
#include "nsCOMPtr.h"
#include "nsClassHashtable.h"
#include "nsCycleCollectionParticipant.h"
#include "nsHashKeys.h"
#include "nsIMessageManager.h"
#include "nsIObserver.h"
#include "nsIObserverService.h"
#include "nsISupports.h"
#include "nsIWeakReferenceUtils.h"
#include "nsStringFwd.h"
#include "nsTArray.h"
#include "nsTHashMap.h"
#include "nsTObserverArray.h"
#include "nscore.h"
class nsFrameLoader;
class nsIRunnable;
namespace mozilla {
class ErrorResult;
namespace dom {
class ChildProcessMessageManager;
class ChromeMessageBroadcaster;
class ClonedMessageData;
class MessageBroadcaster;
class MessageListener;
class MessageListenerManager;
class MessageManagerReporter;
class ParentProcessMessageManager;
class ProcessMessageManager;
namespace ipc {
class MessageManagerCallback;
class WritableSharedMap;
enum class MessageManagerFlags {
  MM_NONE = 0,
  MM_CHROME = 1,
  MM_GLOBAL = 2,
  MM_PROCESSMANAGER = 4,
  MM_BROADCASTER = 8,
  MM_OWNSCALLBACK = 16
};
MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(MessageManagerFlags);
void UnpackClonedMessageData(const ClonedMessageData& aClonedData,
                             StructuredCloneData& aData);
}  // namespace ipc
}  // namespace dom
}  // namespace mozilla
struct nsMessageListenerInfo {
  bool operator==(const nsMessageListenerInfo& aOther) const {
    return &aOther == this;
  }
  // If mWeakListener is null then mStrongListener holds a MessageListener.
  // If mWeakListener is non-null then mStrongListener contains null.
  RefPtr<mozilla::dom::MessageListener> mStrongListener;
  nsWeakPtr mWeakListener;
  bool mListenWhenClosed;
};
class nsFrameMessageManager : public nsIMessageSender {
  friend class mozilla::dom::MessageManagerReporter;
  using StructuredCloneData = mozilla::dom::ipc::StructuredCloneData;
 protected:
  using MessageManagerFlags = mozilla::dom::ipc::MessageManagerFlags;
  nsFrameMessageManager(mozilla::dom::ipc::MessageManagerCallback* aCallback,
                        MessageManagerFlags aFlags);
  virtual ~nsFrameMessageManager();
 public:
  explicit nsFrameMessageManager(
      mozilla::dom::ipc::MessageManagerCallback* aCallback)
      : nsFrameMessageManager(aCallback, MessageManagerFlags::MM_NONE) {}
  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(nsFrameMessageManager)
  void MarkForCC();
  // MessageListenerManager
  void AddMessageListener(const nsAString& aMessageName,
                          mozilla::dom::MessageListener& aListener,
                          bool aListenWhenClosed, mozilla::ErrorResult& aError);
  void RemoveMessageListener(const nsAString& aMessageName,
                             mozilla::dom::MessageListener& aListener,
                             mozilla::ErrorResult& aError);
  void AddWeakMessageListener(const nsAString& aMessageName,
                              mozilla::dom::MessageListener& aListener,
                              mozilla::ErrorResult& aError);
  void RemoveWeakMessageListener(const nsAString& aMessageName,
                                 mozilla::dom::MessageListener& aListener,
                                 mozilla::ErrorResult& aError);
  // MessageSender
  void SendAsyncMessage(JSContext* aCx, const nsAString& aMessageName,
                        JS::Handle<JS::Value> aObj,
                        JS::Handle<JS::Value> aTransfers,
                        mozilla::ErrorResult& aError) {
    DispatchAsyncMessage(aCx, aMessageName, aObj, aTransfers, aError);
  }
  already_AddRefed<mozilla::dom::ProcessMessageManager>
  GetProcessMessageManager(mozilla::ErrorResult& aError);
  void GetRemoteType(nsACString& aRemoteType,
                     mozilla::ErrorResult& aError) const;
  // SyncMessageSender
  void SendSyncMessage(JSContext* aCx, const nsAString& aMessageName,
                       JS::Handle<JS::Value> aObj, nsTArray<JS::Value>& aResult,
                       mozilla::ErrorResult& aError);
  // GlobalProcessScriptLoader
  void GetInitialProcessData(JSContext* aCx,
                             JS::MutableHandle<JS::Value> aInitialProcessData,
                             mozilla::ErrorResult& aError);
  mozilla::dom::ipc::WritableSharedMap* SharedData();
  NS_DECL_NSIMESSAGESENDER
  static mozilla::dom::ProcessMessageManager* NewProcessMessageManager(
      bool aIsRemote);
  void ReceiveMessage(
      nsISupports* aTarget, nsFrameLoader* aTargetFrameLoader,
      const nsAString& aMessage, bool aIsSync, StructuredCloneData* aCloneData,
      nsTArray<mozilla::UniquePtr<StructuredCloneData>>* aRetVal,
      mozilla::ErrorResult& aError) {
    ReceiveMessage(aTarget, aTargetFrameLoader, mClosed, aMessage, aIsSync,
                   aCloneData, aRetVal, aError);
  }
  void Disconnect(bool aRemoveFromParent = true);
  void Close();
  void SetCallback(mozilla::dom::ipc::MessageManagerCallback* aCallback);
  mozilla::dom::ipc::MessageManagerCallback* GetCallback() { return mCallback; }
  nsresult DispatchAsyncMessageInternal(JSContext* aCx,
                                        const nsAString& aMessage,
                                        StructuredCloneData& aData);
  bool IsGlobal() { return mGlobal; }
  bool IsBroadcaster() { return mIsBroadcaster; }
  bool IsChrome() { return mChrome; }
  // GetGlobalMessageManager creates the global message manager if it hasn't
  // been yet.
  static already_AddRefed<mozilla::dom::ChromeMessageBroadcaster>
  GetGlobalMessageManager();
  static mozilla::dom::ParentProcessMessageManager* GetParentProcessManager() {
    return sParentProcessManager;
  }
  static mozilla::dom::ChildProcessMessageManager* GetChildProcessManager() {
    return sChildProcessManager;
  }
  static void SetChildProcessManager(
      mozilla::dom::ChildProcessMessageManager* aManager) {
    sChildProcessManager = aManager;
  }
  static bool GetParamsForMessage(JSContext* aCx, const JS::Value& aValue,
                                  const JS::Value& aTransfer,
                                  StructuredCloneData& aData);
  void SetInitialProcessData(JS::Handle<JS::Value> aInitialData);
  void LoadPendingScripts();
 protected:
  friend class MMListenerRemover;
  virtual mozilla::dom::MessageBroadcaster* GetParentManager() {
    return nullptr;
  }
  virtual void ClearParentManager(bool aRemove) {}
  void DispatchAsyncMessage(JSContext* aCx, const nsAString& aMessageName,
                            JS::Handle<JS::Value> aObj,
                            JS::Handle<JS::Value> aTransfers,
                            mozilla::ErrorResult& aError);
  void ReceiveMessage(
      nsISupports* aTarget, nsFrameLoader* aTargetFrameLoader,
      bool aTargetClosed, const nsAString& aMessage, bool aIsSync,
      StructuredCloneData* aCloneData,
      nsTArray<mozilla::UniquePtr<StructuredCloneData>>* aRetVal,
      mozilla::ErrorResult& aError);
  void LoadScript(const nsAString& aURL, bool aAllowDelayedLoad,
                  bool aRunInGlobalScope, mozilla::ErrorResult& aError);
  void RemoveDelayedScript(const nsAString& aURL);
  void GetDelayedScripts(JSContext* aCx, nsTArray<nsTArray<JS::Value>>& aList,
                         mozilla::ErrorResult& aError);
  // We keep the message listeners as arrays in a hastable indexed by the
  // message name. That gives us fast lookups in ReceiveMessage().
  nsClassHashtable<nsStringHashKey,
                   nsAutoTObserverArray<nsMessageListenerInfo, 1>>
      mListeners;
  nsTArray<RefPtr<mozilla::dom::MessageListenerManager>> mChildManagers;
  bool mChrome;            // true if we're in the chrome process
  bool mGlobal;            // true if we're the global frame message manager
  bool mIsProcessManager;  // true if the message manager belongs to the process
                           // realm
  bool mIsBroadcaster;     // true if the message manager is a broadcaster
  bool mOwnsCallback;
  bool mHandlingMessage;
  bool mClosed;  // true if we can no longer send messages
  bool mDisconnected;
  mozilla::dom::ipc::MessageManagerCallback* mCallback;
  mozilla::UniquePtr<mozilla::dom::ipc::MessageManagerCallback> mOwnedCallback;
  nsTArray<nsString> mPendingScripts;
  nsTArray<bool> mPendingScriptsGlobalStates;
  JS::Heap<JS::Value> mInitialProcessData;
  RefPtr<mozilla::dom::ipc::WritableSharedMap> mSharedData;
  void LoadPendingScripts(nsFrameMessageManager* aManager,
                          nsFrameMessageManager* aChildMM);
 public:
  static mozilla::dom::ParentProcessMessageManager* sParentProcessManager;
  static nsFrameMessageManager* sSameProcessParentManager;
  static nsTArray<nsCOMPtr<nsIRunnable>>* sPendingSameProcessAsyncMessages;
 private:
  static mozilla::dom::ChildProcessMessageManager* sChildProcessManager;
};
/* A helper class for taking care of many details for async message sending
   within a single process.  Intended to be used like so:
   class MyAsyncMessage : public nsSameProcessAsyncMessageBase, public Runnable
   {
     NS_IMETHOD Run() {
       ReceiveMessage(..., ...);
       return NS_OK;
     }
   };
   RefPtr<nsSameProcessAsyncMessageBase> ev = new MyAsyncMessage();
   nsresult rv = ev->Init(...);
   if (NS_SUCCEEDED(rv)) {
     NS_DispatchToMainThread(ev);
   }
*/
class nsSameProcessAsyncMessageBase {
 public:
  using StructuredCloneData = mozilla::dom::ipc::StructuredCloneData;
  nsSameProcessAsyncMessageBase();
  nsresult Init(const nsAString& aMessage, StructuredCloneData& aData);
  void ReceiveMessage(nsISupports* aTarget, nsFrameLoader* aTargetFrameLoader,
                      nsFrameMessageManager* aManager);
 private:
  nsSameProcessAsyncMessageBase(const nsSameProcessAsyncMessageBase&);
  nsString mMessage;
  StructuredCloneData mData;
#ifdef DEBUG
  bool mCalledInit;
#endif
};
class nsScriptCacheCleaner;
struct nsMessageManagerScriptHolder {
  explicit nsMessageManagerScriptHolder(JS::Stencil* aStencil)
      : mStencil(aStencil) {
    MOZ_COUNT_CTOR(nsMessageManagerScriptHolder);
  }
  MOZ_COUNTED_DTOR(nsMessageManagerScriptHolder)
  RefPtr<JS::Stencil> mStencil;
};
class nsMessageManagerScriptExecutor {
 public:
  static void PurgeCache();
  static void Shutdown();
  void MarkScopesForCC();
 protected:
  friend class nsMessageManagerScriptCx;
  nsMessageManagerScriptExecutor() {
    MOZ_COUNT_CTOR(nsMessageManagerScriptExecutor);
  }
  MOZ_COUNTED_DTOR(nsMessageManagerScriptExecutor)
  void DidCreateScriptLoader();
  void LoadScriptInternal(JS::Handle<JSObject*> aMessageManager,
                          const nsAString& aURL, bool aRunInUniqueScope);
  already_AddRefed<JS::Stencil> TryCacheLoadAndCompileScript(
      const nsAString& aURL, bool aRunInUniqueScope,
      JS::Handle<JSObject*> aMessageManager);
  bool Init();
  void Trace(const TraceCallbacks& aCallbacks, void* aClosure);
  void Unlink();
  AutoTArray<JS::Heap<JSObject*>, 2> mAnonymousGlobalScopes;
  // Returns true if this is a process message manager. There should only be a
  // single process message manager per session, so instances of this type will
  // optimize their script loading to avoid unnecessary duplication.
  virtual bool IsProcessScoped() const { return false; }
  static nsTHashMap<nsStringHashKey, nsMessageManagerScriptHolder*>*
      sCachedScripts;
  static mozilla::StaticRefPtr<nsScriptCacheCleaner> sScriptCacheCleaner;
};
class nsScriptCacheCleaner final : public nsIObserver {
  ~nsScriptCacheCleaner() = default;
  NS_DECL_ISUPPORTS
  nsScriptCacheCleaner() {
    nsCOMPtr<nsIObserverService> obsSvc =
        mozilla::services::GetObserverService();
    if (obsSvc) {
      obsSvc->AddObserver(this, "xpcom-shutdown", false);
    }
  }
  NS_IMETHOD Observe(nsISupports* aSubject, const char* aTopic,
                     const char16_t* aData) override {
    if (strcmp("xpcom-shutdown", aTopic) == 0) {
      nsMessageManagerScriptExecutor::Shutdown();
    }
    return NS_OK;
  }
};
#endif