net/base/address_tracker_linux.h

   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 #ifndef NET_BASE_ADDRESS_TRACKER_LINUX_H_
   6 #define NET_BASE_ADDRESS_TRACKER_LINUX_H_
   7
   8 #include <sys/socket.h>  // Needed to include netlink.
   9 // Mask superfluous definition of |struct net|. This is fixed in Linux 2.6.38.
  10 #define net net_kernel
  11 #include <linux/rtnetlink.h>
  12 #undef net
  13
  14 #include <map>
  15
  16 #include "base/basictypes.h"
  17 #include "base/callback.h"
  18 #include "base/compiler_specific.h"
  19 #include "base/hash_tables.h"
  20 #include "base/message_loop.h"
  21 #include "base/synchronization/condition_variable.h"
  22 #include "base/synchronization/lock.h"
  23 #include "net/base/net_util.h"
  24 #include "net/base/network_change_notifier.h"
  25
  26 namespace net {
  27 namespace internal {
  28
  29 // Keeps track of network interface addresses using rtnetlink. Used by
  30 // NetworkChangeNotifier to provide signals to registered IPAddressObservers.
  31 class NET_EXPORT_PRIVATE AddressTrackerLinux
  32     : public MessageLoopForIO::Watcher {
  33  public:
  34   typedef std::map<IPAddressNumber, struct ifaddrmsg> AddressMap;
  35
  36   // Will run |address_callback| when the AddressMap changes and will run
  37   // |link_callback| when the list of online links changes.
  38   AddressTrackerLinux(const base::Closure& address_callback,
  39                       const base::Closure& link_callback);
  40   virtual ~AddressTrackerLinux();
  41
  42   // Starts watching system configuration for changes. The current thread must
  43   // have a MessageLoopForIO.
  44   void Init();
  45
  46   AddressMap GetAddressMap() const;
  47
  48   // Implementation of NetworkChangeNotifierLinux::GetCurrentConnectionType().
  49   // Safe to call from any thread, but will block until Init() has completed.
  50   NetworkChangeNotifier::ConnectionType GetCurrentConnectionType();
  51
  52  private:
  53   friend class AddressTrackerLinuxTest;
  54
  55   // Sets |*address_changed| to indicate whether |address_map_| changed and
  56   // sets |*link_changed| to indicate if |online_links_| changed while reading
  57   // messages from |netlink_fd_|.
  58   void ReadMessages(bool* address_changed, bool* link_changed);
  59
  60   // Sets |*address_changed| to true if |address_map_| changed, sets
  61   // |*link_changed| to true if |online_links_| changed while reading the
  62   // message from |buffer|.
  63   void HandleMessage(const char* buffer,
  64                      size_t length,
  65                      bool* address_changed,
  66                      bool* link_changed);
  67
  68   // Call when some part of initialization failed; forces online and unblocks.
  69   void AbortAndForceOnline();
  70
  71   // MessageLoopForIO::Watcher:
  72   virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE;
  73   virtual void OnFileCanWriteWithoutBlocking(int /* fd */) OVERRIDE;
  74
  75   // Close |netlink_fd_|
  76   void CloseSocket();
  77
  78   base::Closure address_callback_;
  79   base::Closure link_callback_;
  80
  81   int netlink_fd_;
  82   MessageLoopForIO::FileDescriptorWatcher watcher_;
  83
  84   mutable base::Lock address_map_lock_;
  85   AddressMap address_map_;
  86
  87   // Set of interface indices for links that are currently online.
  88   base::hash_set<int> online_links_;
  89
  90   base::Lock is_offline_lock_;
  91   bool is_offline_;
  92   bool is_offline_initialized_;
  93   base::ConditionVariable is_offline_initialized_cv_;
  94 };
  95
  96 }  // namespace internal
  97 }  // namespace net
  98
  99 #endif  // NET_BASE_ADDRESS_TRACKER_LINUX_H_