1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5// This file defines the type used to provide sources for NotificationService 6// notifications. 7 8#ifndef CONTENT_PUBLIC_BROWSER_NOTIFICATION_SOURCE_H_ 9#define CONTENT_PUBLIC_BROWSER_NOTIFICATION_SOURCE_H_ 10 11#include "base/basictypes.h" 12#include "content/common/content_export.h" 13 14namespace content { 15 16// Do not declare a NotificationSource directly--use either 17// "Source<sourceclassname>(sourceclasspointer)" or 18// NotificationService::AllSources(). 19class CONTENT_EXPORT NotificationSource { 20 public: 21 NotificationSource(const NotificationSource& other) : ptr_(other.ptr_) {} 22 ~NotificationSource() {} 23 24 // NotificationSource can be used as the index for a map; this method 25 // returns the pointer to the current source as an identifier, for use as a 26 // map index. 27 uintptr_t map_key() const { return reinterpret_cast<uintptr_t>(ptr_); } 28 29 bool operator!=(const NotificationSource& other) const { 30 return ptr_ != other.ptr_; 31 } 32 bool operator==(const NotificationSource& other) const { 33 return ptr_ == other.ptr_; 34 } 35 36 protected: 37 explicit NotificationSource(const void* ptr) : ptr_(ptr) {} 38 39 // Declaring this const allows Source<T> to be used with both T = Foo and 40 // T = const Foo. 41 const void* ptr_; 42}; 43 44template <class T> 45class Source : public NotificationSource { 46 public: 47 // TODO(erg): Our code hard relies on implicit conversion 48 Source(const T* ptr) : NotificationSource(ptr) {} // NOLINT 49 Source(const NotificationSource& other) // NOLINT 50 : NotificationSource(other) {} 51 52 T* operator->() const { return ptr(); } 53 // The casts here allow this to compile with both T = Foo and T = const Foo. 54 T* ptr() const { return static_cast<T*>(const_cast<void*>(ptr_)); } 55}; 56 57} // namespace content 58 59#endif // CONTENT_PUBLIC_BROWSER_NOTIFICATION_SOURCE_H_ 60