Quelle EventDispatcher.cpp Sprache: C

/* -*- Mode: c++; c-basic-offset: 2; tab-width: 20; indent-tabs-mode: nil; -*-
* vim: set sw=2 ts=4 expandtab:
* 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/. */

#include "EventDispatcher.h"

#include "JavaBuiltins.h"
#include "nsAppShell.h"
#include "nsJSUtils.h"
#include "js/Array.h"  // JS::GetArrayLength, JS::IsArrayObject, JS::NewArrayObject
#include "js/PropertyAndElement.h"  // JS_Enumerate, JS_GetElement, JS_GetProperty, JS_GetPropertyById, JS_SetElement, JS_SetUCProperty
#include "js/String.h"              // JS::StringHasLatin1Chars
#include "js/Warnings.h"            // JS::WarnUTF8
#include "xpcpublic.h"

#include "mozilla/fallible.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/java/EventCallbackWrappers.h"
#include "mozilla/jni/GeckoBundleUtils.h"

namespace mozilla {
namespace widget {

namespace detail {

bool CheckJS(JSContext* aCx, bool aResult) {
  if (!aResult) {
    JS_ClearPendingException(aCx);
  }
  return aResult;
}

nsresult BoxData(const nsAString& aEvent, JSContext* aCx,
                 JS::Handle<JS::Value> aData, jni::Object::LocalRef& aOut,
                 bool aObjectOnly) {
  nsresult rv = jni::BoxData(aCx, aData, aOut, aObjectOnly);
  if (rv != NS_ERROR_INVALID_ARG) {
    return rv;
  }

  NS_ConvertUTF16toUTF8 event(aEvent);
  if (JS_IsExceptionPending(aCx)) {
    JS::WarnUTF8(aCx, "Error dispatching %s", event.get());
  } else {
    JS_ReportErrorUTF8(aCx, "Invalid event data for %s", event.get());
  }
  return NS_ERROR_INVALID_ARG;
}

nsresult UnboxString(JSContext* aCx, const jni::Object::LocalRef& aData,
                     JS::MutableHandle<JS::Value> aOut) {
  if (!aData) {
    aOut.setNull();
    return NS_OK;
  }

  MOZ_ASSERT(aData.IsInstanceOf<jni::String>());

  JNIEnv* const env = aData.Env();
  const jstring jstr = jstring(aData.Get());
  const size_t len = env->GetStringLength(jstr);
  const jchar* const jchars = env->GetStringChars(jstr, nullptr);

  if (NS_WARN_IF(!jchars)) {
    env->ExceptionClear();
    return NS_ERROR_FAILURE;
  }

  auto releaseStr = MakeScopeExit([env, jstr, jchars] {
    env->ReleaseStringChars(jstr, jchars);
    env->ExceptionClear();
  });

  JS::Rooted<JSString*> str(
      aCx,
      JS_NewUCStringCopyN(aCx, reinterpret_cast<const char16_t*>(jchars), len));
  NS_ENSURE_TRUE(CheckJS(aCx, !!str), NS_ERROR_FAILURE);

  aOut.setString(str);
  return NS_OK;
}

nsresult UnboxValue(JSContext* aCx, const jni::Object::LocalRef& aData,
                    JS::MutableHandle<JS::Value> aOut);

nsresult UnboxBundle(JSContext* aCx, const jni::Object::LocalRef& aData,
                     JS::MutableHandle<JS::Value> aOut) {
  if (!aData) {
    aOut.setNull();
    return NS_OK;
  }

  MOZ_ASSERT(aData.IsInstanceOf<java::GeckoBundle>());

  JNIEnv* const env = aData.Env();
  const auto& bundle = java::GeckoBundle::Ref::From(aData);
  jni::ObjectArray::LocalRef keys = bundle->Keys();
  jni::ObjectArray::LocalRef values = bundle->Values();
  const size_t len = keys->Length();
  JS::Rooted<JSObject*> obj(aCx, JS_NewPlainObject(aCx));

  NS_ENSURE_TRUE(CheckJS(aCx, !!obj), NS_ERROR_FAILURE);
  NS_ENSURE_TRUE(values->Length() == len, NS_ERROR_FAILURE);

  for (size_t i = 0; i < len; i++) {
    jni::String::LocalRef key = keys->GetElement(i);
    const size_t keyLen = env->GetStringLength(key.Get());
    const jchar* const keyChars = env->GetStringChars(key.Get(), nullptr);
    if (NS_WARN_IF(!keyChars)) {
      env->ExceptionClear();
      return NS_ERROR_FAILURE;
    }

    auto releaseKeyChars = MakeScopeExit([env, &key, keyChars] {
      env->ReleaseStringChars(key.Get(), keyChars);
      env->ExceptionClear();
    });

    JS::Rooted<JS::Value> value(aCx);
    nsresult rv = UnboxValue(aCx, values->GetElement(i), &value);
    if (rv == NS_ERROR_INVALID_ARG && !JS_IsExceptionPending(aCx)) {
      JS_ReportErrorUTF8(
          aCx, "Invalid event data property %s",
          NS_ConvertUTF16toUTF8(reinterpret_cast<const char16_t*>(keyChars),
                                keyLen)
              .get());
    }
    NS_ENSURE_SUCCESS(rv, rv);

    NS_ENSURE_TRUE(
        CheckJS(aCx, JS_SetUCProperty(
                         aCx, obj, reinterpret_cast<const char16_t*>(keyChars),
                         keyLen, value)),
        NS_ERROR_FAILURE);
  }

  aOut.setObject(*obj);
  return NS_OK;
}

template <typename Type, typename JNIType, typename ArrayType,
          JNIType* (JNIEnv::*GetElements)(ArrayType, jboolean*),
          void (JNIEnv::*ReleaseElements)(ArrayType, JNIType*, jint),
          JS::Value (*ToValue)(Type)>
nsresult UnboxArrayPrimitive(JSContext* aCx, const jni::Object::LocalRef& aData,
                             JS::MutableHandle<JS::Value> aOut) {
  JNIEnv* const env = aData.Env();
  const ArrayType jarray = ArrayType(aData.Get());
  JNIType* const array = (env->*GetElements)(jarray, nullptr);
  JS::RootedVector<JS::Value> elements(aCx);

  if (NS_WARN_IF(!array)) {
    env->ExceptionClear();
    return NS_ERROR_FAILURE;
  }

  auto releaseArray = MakeScopeExit([env, jarray, array] {
    (env->*ReleaseElements)(jarray, array, JNI_ABORT);
    env->ExceptionClear();
  });

  const size_t len = env->GetArrayLength(jarray);
  NS_ENSURE_TRUE(elements.initCapacity(len), NS_ERROR_FAILURE);

  for (size_t i = 0; i < len; i++) {
    NS_ENSURE_TRUE(elements.append((*ToValue)(Type(array[i]))),
                   NS_ERROR_FAILURE);
  }

  JS::Rooted<JSObject*> obj(
      aCx, JS::NewArrayObject(aCx, JS::HandleValueArray(elements)));
  NS_ENSURE_TRUE(CheckJS(aCx, !!obj), NS_ERROR_FAILURE);

  aOut.setObject(*obj);
  return NS_OK;
}

struct StringArray : jni::ObjectBase<StringArray> {
  static const char name[];
};

struct GeckoBundleArray : jni::ObjectBase<GeckoBundleArray> {
  static const char name[];
};

const char StringArray::name[] = "[Ljava/lang/String;";
const char GeckoBundleArray::name[] = "[Lorg/mozilla/gecko/util/GeckoBundle;";

template <nsresult (*Unbox)(JSContext*, const jni::Object::LocalRef&,
                            JS::MutableHandle<JS::Value>)>
nsresult UnboxArrayObject(JSContext* aCx, const jni::Object::LocalRef& aData,
                          JS::MutableHandle<JS::Value> aOut) {
  jni::ObjectArray::LocalRef array(aData.Env(),
                                   jni::ObjectArray::Ref::From(aData));
  const size_t len = array->Length();
  JS::Rooted<JSObject*> obj(aCx, JS::NewArrayObject(aCx, len));
  NS_ENSURE_TRUE(CheckJS(aCx, !!obj), NS_ERROR_FAILURE);

  for (size_t i = 0; i < len; i++) {
    jni::Object::LocalRef element = array->GetElement(i);
    JS::Rooted<JS::Value> value(aCx);
    nsresult rv = (*Unbox)(aCx, element, &value);
    NS_ENSURE_SUCCESS(rv, rv);

    NS_ENSURE_TRUE(CheckJS(aCx, JS_SetElement(aCx, obj, i, value)),
                   NS_ERROR_FAILURE);
  }

  aOut.setObject(*obj);
  return NS_OK;
}

nsresult UnboxValue(JSContext* aCx, const jni::Object::LocalRef& aData,
                    JS::MutableHandle<JS::Value> aOut) {
  using jni::Java2Native;

  if (!aData) {
    aOut.setNull();
  } else if (aData.IsInstanceOf<jni::Boolean>()) {
    aOut.setBoolean(Java2Native<bool>(aData, aData.Env()));
  } else if (aData.IsInstanceOf<jni::Integer>()) {
    aOut.setInt32(Java2Native<int>(aData, aData.Env()));
  } else if (aData.IsInstanceOf<jni::Byte>() ||
             aData.IsInstanceOf<jni::Short>()) {
    aOut.setInt32(java::sdk::Number::Ref::From(aData)->IntValue());
  } else if (aData.IsInstanceOf<jni::Double>()) {
    aOut.setNumber(Java2Native<double>(aData, aData.Env()));
  } else if (aData.IsInstanceOf<jni::Float>() ||
             aData.IsInstanceOf<jni::Long>()) {
    aOut.setNumber(java::sdk::Number::Ref::From(aData)->DoubleValue());
  } else if (aData.IsInstanceOf<jni::String>()) {
    return UnboxString(aCx, aData, aOut);
  } else if (aData.IsInstanceOf<jni::Character>()) {
    return UnboxString(aCx, java::sdk::String::ValueOf(aData), aOut);
  } else if (aData.IsInstanceOf<java::GeckoBundle>()) {
    return UnboxBundle(aCx, aData, aOut);

  } else if (aData.IsInstanceOf<jni::BooleanArray>()) {
    return UnboxArrayPrimitive<
        bool, jboolean, jbooleanArray, &JNIEnv::GetBooleanArrayElements,
        &JNIEnv::ReleaseBooleanArrayElements, &JS::BooleanValue>(aCx, aData,
                                                                 aOut);

  } else if (aData.IsInstanceOf<jni::IntArray>()) {
    return UnboxArrayPrimitive<
        int32_t, jint, jintArray, &JNIEnv::GetIntArrayElements,
        &JNIEnv::ReleaseIntArrayElements, &JS::Int32Value>(aCx, aData, aOut);

  } else if (aData.IsInstanceOf<jni::DoubleArray>()) {
    return UnboxArrayPrimitive<
        double, jdouble, jdoubleArray, &JNIEnv::GetDoubleArrayElements,
        &JNIEnv::ReleaseDoubleArrayElements, &JS::DoubleValue>(aCx, aData,
                                                               aOut);

  } else if (aData.IsInstanceOf<StringArray>()) {
    return UnboxArrayObject<&UnboxString>(aCx, aData, aOut);
  } else if (aData.IsInstanceOf<GeckoBundleArray>()) {
    return UnboxArrayObject<&UnboxBundle>(aCx, aData, aOut);
  } else {
    NS_WARNING("Invalid type");
    return NS_ERROR_INVALID_ARG;
  }
  return NS_OK;
}

nsresult UnboxData(jni::String::Param aEvent, JSContext* aCx,
                   jni::Object::Param aData, JS::MutableHandle<JS::Value> aOut,
                   bool aBundleOnly) {
  MOZ_ASSERT(NS_IsMainThread());

  jni::Object::LocalRef jniData(jni::GetGeckoThreadEnv(), aData);
  nsresult rv = NS_ERROR_INVALID_ARG;

  if (!aBundleOnly) {
    rv = UnboxValue(aCx, jniData, aOut);
  } else if (!jniData || jniData.IsInstanceOf<java::GeckoBundle>()) {
    rv = UnboxBundle(aCx, jniData, aOut);
  }
  if (rv != NS_ERROR_INVALID_ARG || !aEvent) {
    return rv;
  }

  nsCString event = aEvent->ToCString();
  if (JS_IsExceptionPending(aCx)) {
    JS::WarnUTF8(aCx, "Error dispatching %s", event.get());
  } else {
    JS_ReportErrorUTF8(aCx, "Invalid event data for %s", event.get());
  }
  return NS_ERROR_INVALID_ARG;
}

class JavaCallbackDelegate final : public nsIGeckoViewEventCallback {
  const java::EventCallback::GlobalRef mCallback;

  virtual ~JavaCallbackDelegate() {}

  NS_IMETHOD Call(JSContext* aCx, JS::Handle<JS::Value> aData,
                  void (java::EventCallback::*aCall)(jni::Object::Param)
                      const) {
    MOZ_ASSERT(NS_IsMainThread());

    jni::Object::LocalRef data(jni::GetGeckoThreadEnv());
    nsresult rv = BoxData(u"callback"_ns, aCx, aData, data,
                          /* ObjectOnly */ false);
    NS_ENSURE_SUCCESS(rv, rv);

    dom::AutoNoJSAPI nojsapi;

    (java::EventCallback(*mCallback).*aCall)(data);
    return NS_OK;
  }

public:
  explicit JavaCallbackDelegate(java::EventCallback::Param aCallback)
      : mCallback(jni::GetGeckoThreadEnv(), aCallback) {}

  NS_DECL_ISUPPORTS

  NS_IMETHOD OnSuccess(JS::Handle<JS::Value> aData, JSContext* aCx) override {
    return Call(aCx, aData, &java::EventCallback::SendSuccess);
  }

  NS_IMETHOD OnError(JS::Handle<JS::Value> aData, JSContext* aCx) override {
    return Call(aCx, aData, &java::EventCallback::SendError);
  }
};

NS_IMPL_ISUPPORTS(JavaCallbackDelegate, nsIGeckoViewEventCallback)

class NativeCallbackDelegateSupport final
    : public java::EventDispatcher::NativeCallbackDelegate ::Natives<
          NativeCallbackDelegateSupport> {
  using CallbackDelegate = java::EventDispatcher::NativeCallbackDelegate;
  using Base = CallbackDelegate::Natives<NativeCallbackDelegateSupport>;

  const nsCOMPtr<nsIGeckoViewEventCallback> mCallback;
  const nsCOMPtr<nsIGeckoViewEventFinalizer> mFinalizer;
  const nsCOMPtr<nsIGlobalObject> mGlobalObject;

  void Call(jni::Object::Param aData,
            nsresult (nsIGeckoViewEventCallback::*aCall)(JS::Handle<JS::Value>,
                                                         JSContext*)) {
    MOZ_ASSERT(NS_IsMainThread());

    // Use either the attached window's realm or a default realm.

    dom::AutoJSAPI jsapi;
    NS_ENSURE_TRUE_VOID(jsapi.Init(mGlobalObject));

    JS::Rooted<JS::Value> data(jsapi.cx());
    nsresult rv = UnboxData(u"callback"_ns, jsapi.cx(), aData, &data,
                            /* BundleOnly */ false);
    NS_ENSURE_SUCCESS_VOID(rv);

    rv = (mCallback->*aCall)(data, jsapi.cx());
    NS_ENSURE_SUCCESS_VOID(rv);
  }

public:
  using Base::AttachNative;

  template <typename Functor>
  static void OnNativeCall(Functor&& aCall) {
    if (NS_IsMainThread()) {
      // Invoke callbacks synchronously if we're already on Gecko thread.
      return aCall();
    }
    NS_DispatchToMainThread(
        NS_NewRunnableFunction("OnNativeCall", std::move(aCall)));
  }

  static void Finalize(const CallbackDelegate::LocalRef& aInstance) {
    DisposeNative(aInstance);
  }

  NativeCallbackDelegateSupport(nsIGeckoViewEventCallback* callback,
                                nsIGeckoViewEventFinalizer* finalizer,
                                nsIGlobalObject* globalObject)
      : mCallback(callback),
        mFinalizer(finalizer),
        mGlobalObject(globalObject) {}

  ~NativeCallbackDelegateSupport() {
    if (mFinalizer) {
      mFinalizer->OnFinalize();
    }
  }

  void SendSuccess(jni::Object::Param aData) {
    Call(aData, &nsIGeckoViewEventCallback::OnSuccess);
  }

  void SendError(jni::Object::Param aData) {
    Call(aData, &nsIGeckoViewEventCallback::OnError);
  }
};

class FinalizingCallbackDelegate final : public nsIGeckoViewEventCallback {
  const nsCOMPtr<nsIGeckoViewEventCallback> mCallback;
  const nsCOMPtr<nsIGeckoViewEventFinalizer> mFinalizer;

  virtual ~FinalizingCallbackDelegate() {
    if (mFinalizer) {
      mFinalizer->OnFinalize();
    }
  }

public:
  FinalizingCallbackDelegate(nsIGeckoViewEventCallback* aCallback,
                             nsIGeckoViewEventFinalizer* aFinalizer)
      : mCallback(aCallback), mFinalizer(aFinalizer) {}

  NS_DECL_ISUPPORTS
  NS_FORWARD_NSIGECKOVIEWEVENTCALLBACK(mCallback->);
};

NS_IMPL_ISUPPORTS(FinalizingCallbackDelegate, nsIGeckoViewEventCallback)

}  // namespace detail

using namespace detail;

NS_IMPL_ISUPPORTS(EventDispatcher, nsIGeckoViewEventDispatcher)

nsIGlobalObject* EventDispatcher::GetGlobalObject() {
  if (mDOMWindow) {
    return nsGlobalWindowInner::Cast(mDOMWindow->GetCurrentInnerWindow());
  }
  return xpc::NativeGlobal(xpc::PrivilegedJunkScope());
}

nsresult EventDispatcher::DispatchOnGecko(
    ListenersList* list, const nsAString& aEvent, JS::Handle<JS::Value> aData,
    nsIGeckoViewEventCallback* aCallback) {
  MOZ_ASSERT(NS_IsMainThread());
  dom::AutoNoJSAPI nojsapi;

  list->lockCount++;

  auto iteratingScope = MakeScopeExit([list] {
    list->lockCount--;
    if (list->lockCount || !list->unregistering) {
      return;
    }

    list->unregistering = false;
    for (ssize_t i = list->listeners.Count() - 1; i >= 0; i--) {
      if (list->listeners[i]) {
        continue;
      }
      list->listeners.RemoveObjectAt(i);
    }
  });

  const size_t count = list->listeners.Count();
  for (size_t i = 0; i < count; i++) {
    if (!list->listeners[i]) {
      // Unregistered.
      continue;
    }
    const nsresult rv = list->listeners[i]->OnEvent(aEvent, aData, aCallback);
    Unused << NS_WARN_IF(NS_FAILED(rv));
  }
  return NS_OK;
}

java::EventDispatcher::NativeCallbackDelegate::LocalRef
EventDispatcher::WrapCallback(nsIGeckoViewEventCallback* aCallback,
                              nsIGeckoViewEventFinalizer* aFinalizer) {
  if (!aCallback) {
    return java::EventDispatcher::NativeCallbackDelegate::LocalRef(
        jni::GetGeckoThreadEnv());
  }

  java::EventDispatcher::NativeCallbackDelegate::LocalRef callback =
      java::EventDispatcher::NativeCallbackDelegate::New();
  NativeCallbackDelegateSupport::AttachNative(
      callback, MakeUnique<NativeCallbackDelegateSupport>(aCallback, aFinalizer,
                                                          GetGlobalObject()));
  return callback;
}

bool EventDispatcher::HasListener(const char16_t* aEvent) {
  java::EventDispatcher::LocalRef dispatcher(mDispatcher);
  if (!dispatcher) {
    return false;
  }

  nsDependentString event(aEvent);
  return dispatcher->HasListener(event);
}

NS_IMETHODIMP
EventDispatcher::Dispatch(JS::Handle<JS::Value> aEvent,
                          JS::Handle<JS::Value> aData,
                          nsIGeckoViewEventCallback* aCallback,
                          nsIGeckoViewEventFinalizer* aFinalizer,
                          JSContext* aCx) {
  MOZ_ASSERT(NS_IsMainThread());

  if (!aEvent.isString()) {
    NS_WARNING("Invalid event name");
    return NS_ERROR_INVALID_ARG;
  }

  nsAutoJSString event;
  NS_ENSURE_TRUE(CheckJS(aCx, event.init(aCx, aEvent.toString())),
                 NS_ERROR_OUT_OF_MEMORY);

  // Don't need to lock here because we're on the main thread, and we can't
  // race against Register/UnregisterListener.

  ListenersList* list = mListenersMap.Get(event);
  if (list) {
    if (!aCallback || !aFinalizer) {
      return DispatchOnGecko(list, event, aData, aCallback);
    }
    nsCOMPtr<nsIGeckoViewEventCallback> callback(
        new FinalizingCallbackDelegate(aCallback, aFinalizer));
    return DispatchOnGecko(list, event, aData, callback);
  }

  java::EventDispatcher::LocalRef dispatcher(mDispatcher);
  if (!dispatcher) {
    return NS_OK;
  }

  jni::Object::LocalRef data(jni::GetGeckoThreadEnv());
  nsresult rv = BoxData(event, aCx, aData, data, /* ObjectOnly */ true);
  // Keep XPConnect from overriding the JSContext exception with one
  // based on the nsresult.
  //
  // XXXbz Does xpconnect still do that?  Needs to be checked/tested.
  NS_ENSURE_SUCCESS(rv, JS_IsExceptionPending(aCx) ? NS_OK : rv);

  dom::AutoNoJSAPI nojsapi;
  dispatcher->DispatchToThreads(event, data,
                                WrapCallback(aCallback, aFinalizer));
  return NS_OK;
}

nsresult EventDispatcher::Dispatch(const char16_t* aEvent,
                                   java::GeckoBundle::Param aData,
                                   nsIGeckoViewEventCallback* aCallback) {
  nsDependentString event(aEvent);

  ListenersList* list = mListenersMap.Get(event);
  if (list) {
    dom::AutoJSAPI jsapi;
    NS_ENSURE_TRUE(jsapi.Init(GetGlobalObject()), NS_ERROR_FAILURE);
    JS::Rooted<JS::Value> data(jsapi.cx());
    nsresult rv = UnboxData(/* Event */ nullptr, jsapi.cx(), aData, &data,
                            /* BundleOnly */ true);
    NS_ENSURE_SUCCESS(rv, rv);
    return DispatchOnGecko(list, event, data, aCallback);
  }

  java::EventDispatcher::LocalRef dispatcher(mDispatcher);
  if (!dispatcher) {
    return NS_OK;
  }

  dispatcher->DispatchToThreads(event, aData, WrapCallback(aCallback));
  return NS_OK;
}

nsresult EventDispatcher::IterateEvents(JSContext* aCx,
                                        JS::Handle<JS::Value> aEvents,
                                        IterateEventsCallback aCallback,
                                        nsIGeckoViewEventListener* aListener) {
  MOZ_ASSERT(NS_IsMainThread());

  MutexAutoLock lock(mLock);

  auto processEvent = [this, aCx, aCallback,
                       aListener](JS::Handle<JS::Value> event) -> nsresult {
    nsAutoJSString str;
    NS_ENSURE_TRUE(CheckJS(aCx, str.init(aCx, event.toString())),
                   NS_ERROR_OUT_OF_MEMORY);
    return (this->*aCallback)(str, aListener);
  };

  if (aEvents.isString()) {
    return processEvent(aEvents);
  }

  bool isArray = false;
  NS_ENSURE_TRUE(aEvents.isObject(), NS_ERROR_INVALID_ARG);
  NS_ENSURE_TRUE(CheckJS(aCx, JS::IsArrayObject(aCx, aEvents, &isArray)),
                 NS_ERROR_INVALID_ARG);
  NS_ENSURE_TRUE(isArray, NS_ERROR_INVALID_ARG);

  JS::Rooted<JSObject*> events(aCx, &aEvents.toObject());
  uint32_t length = 0;
  NS_ENSURE_TRUE(CheckJS(aCx, JS::GetArrayLength(aCx, events, &length)),
                 NS_ERROR_INVALID_ARG);
  NS_ENSURE_TRUE(length, NS_ERROR_INVALID_ARG);

  for (size_t i = 0; i < length; i++) {
    JS::Rooted<JS::Value> event(aCx);
    NS_ENSURE_TRUE(CheckJS(aCx, JS_GetElement(aCx, events, i, &event)),
                   NS_ERROR_INVALID_ARG);
    NS_ENSURE_TRUE(event.isString(), NS_ERROR_INVALID_ARG);

    const nsresult rv = processEvent(event);
    NS_ENSURE_SUCCESS(rv, rv);
  }
  return NS_OK;
}

nsresult EventDispatcher::RegisterEventLocked(
    const nsAString& aEvent, nsIGeckoViewEventListener* aListener) {
  ListenersList* list = mListenersMap.GetOrInsertNew(aEvent);

#ifdef DEBUG
  for (ssize_t i = 0; i < list->listeners.Count(); i++) {
    NS_ENSURE_TRUE(list->listeners[i] != aListener,
                   NS_ERROR_ALREADY_INITIALIZED);
  }
#endif

  list->listeners.AppendObject(aListener);
  return NS_OK;
}

NS_IMETHODIMP
EventDispatcher::RegisterListener(nsIGeckoViewEventListener* aListener,
                                  JS::Handle<JS::Value> aEvents,
                                  JSContext* aCx) {
  return IterateEvents(aCx, aEvents, &EventDispatcher::RegisterEventLocked,
                       aListener);
}

nsresult EventDispatcher::UnregisterEventLocked(
    const nsAString& aEvent, nsIGeckoViewEventListener* aListener) {
  ListenersList* list = mListenersMap.Get(aEvent);
#ifdef DEBUG
  NS_ENSURE_TRUE(list, NS_ERROR_NOT_INITIALIZED);
#else
  NS_ENSURE_TRUE(list, NS_OK);
#endif

  DebugOnly<bool> found = false;
  for (ssize_t i = list->listeners.Count() - 1; i >= 0; i--) {
    if (list->listeners[i] != aListener) {
      continue;
    }
    if (list->lockCount) {
      // Only mark for removal when list is locked.
      list->listeners.ReplaceObjectAt(nullptr, i);
      list->unregistering = true;
    } else {
      list->listeners.RemoveObjectAt(i);
    }
    found = true;
  }
#ifdef DEBUG
  return found ? NS_OK : NS_ERROR_NOT_INITIALIZED;
#else
  return NS_OK;
#endif
}

NS_IMETHODIMP
EventDispatcher::UnregisterListener(nsIGeckoViewEventListener* aListener,
                                    JS::Handle<JS::Value> aEvents,
                                    JSContext* aCx) {
  return IterateEvents(aCx, aEvents, &EventDispatcher::UnregisterEventLocked,
                       aListener);
}

void EventDispatcher::Attach(java::EventDispatcher::Param aDispatcher,
                             nsPIDOMWindowOuter* aDOMWindow) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aDispatcher);

  java::EventDispatcher::LocalRef dispatcher(mDispatcher);

  if (dispatcher) {
    if (dispatcher == aDispatcher) {
      // Only need to update the window.
      mDOMWindow = aDOMWindow;
      return;
    }
    dispatcher->SetAttachedToGecko(java::EventDispatcher::REATTACHING);
  }

  dispatcher = java::EventDispatcher::LocalRef(aDispatcher);
  NativesBase::AttachNative(dispatcher, this);
  mDispatcher = dispatcher;
  mDOMWindow = aDOMWindow;

  dispatcher->SetAttachedToGecko(java::EventDispatcher::ATTACHED);
}

void EventDispatcher::Shutdown() {
  mDispatcher = nullptr;
  mDOMWindow = nullptr;
}

void EventDispatcher::Detach() {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(mDispatcher);

  java::EventDispatcher::GlobalRef dispatcher(mDispatcher);

  // SetAttachedToGecko will call disposeNative for us later on the Gecko
  // thread to make sure all pending dispatchToGecko calls have completed.
  if (dispatcher) {
    dispatcher->SetAttachedToGecko(java::EventDispatcher::DETACHED);
  }

  Shutdown();
}

bool EventDispatcher::HasGeckoListener(jni::String::Param aEvent) {
  // Can be called from any thread.
  MutexAutoLock lock(mLock);
  return !!mListenersMap.Get(aEvent->ToString());
}

void EventDispatcher::DispatchToGecko(jni::String::Param aEvent,
                                      jni::Object::Param aData,
                                      jni::Object::Param aCallback) {
  MOZ_ASSERT(NS_IsMainThread());

  // Don't need to lock here because we're on the main thread, and we can't
  // race against Register/UnregisterListener.

  nsString event = aEvent->ToString();
  ListenersList* list = mListenersMap.Get(event);
  if (!list || list->listeners.IsEmpty()) {
    return;
  }

  // Use the same compartment as the attached window if possible, otherwise
  // use a default compartment.
  dom::AutoJSAPI jsapi;
  NS_ENSURE_TRUE_VOID(jsapi.Init(GetGlobalObject()));

  JS::Rooted<JS::Value> data(jsapi.cx());
  nsresult rv = UnboxData(aEvent, jsapi.cx(), aData, &data,
                          /* BundleOnly */ true);
  NS_ENSURE_SUCCESS_VOID(rv);

  nsCOMPtr<nsIGeckoViewEventCallback> callback;
  if (aCallback) {
    callback =
        new JavaCallbackDelegate(java::EventCallback::Ref::From(aCallback));
  }

  DispatchOnGecko(list, event, data, callback);
}

/* static */
nsresult EventDispatcher::UnboxBundle(JSContext* aCx, jni::Object::Param aData,
                                      JS::MutableHandle<JS::Value> aOut) {
  return detail::UnboxBundle(aCx, aData, aOut);
}

}  // namespace widget
}  // namespace mozilla

quality95%

¤ Dauer der Verarbeitung: 0.16 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.