mojo/system/waiter_list.h

   1 // Copyright 2013 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 MOJO_SYSTEM_WAITER_LIST_H_
   6 #define MOJO_SYSTEM_WAITER_LIST_H_
   7
   8 #include <list>
   9
  10 #include "base/basictypes.h"
  11 #include "mojo/public/c/system/types.h"
  12 #include "mojo/system/system_impl_export.h"
  13
  14 namespace mojo {
  15 namespace system {
  16
  17 class Waiter;
  18
  19 // |WaiterList| tracks all the |Waiter|s that are waiting on a given
  20 // handle/|Dispatcher|. There should be a |WaiterList| for each handle that can
  21 // be waited on (in any way). In the simple case, the |WaiterList| is owned by
  22 // the |Dispatcher|, whereas in more complex cases it is owned by the secondary
  23 // object (see simple_dispatcher.* and the explanatory comment in core.cc). This
  24 // class is thread-unsafe (all concurrent access must be protected by some
  25 // lock).
  26 class MOJO_SYSTEM_IMPL_EXPORT WaiterList {
  27  public:
  28   WaiterList();
  29   ~WaiterList();
  30
  31   void AwakeWaitersForStateChange(MojoWaitFlags satisfied_flags,
  32                                   MojoWaitFlags satisfiable_flags);
  33   void CancelAllWaiters();
  34   void AddWaiter(Waiter* waiter, MojoWaitFlags flags, MojoResult wake_result);
  35   void RemoveWaiter(Waiter* waiter);
  36
  37  private:
  38   struct WaiterInfo {
  39     WaiterInfo(Waiter* waiter, MojoWaitFlags flags, MojoResult wake_result)
  40         : waiter(waiter), flags(flags), wake_result(wake_result) {}
  41
  42     Waiter* waiter;
  43     MojoWaitFlags flags;
  44     MojoResult wake_result;
  45   };
  46   typedef std::list<WaiterInfo> WaiterInfoList;
  47
  48   WaiterInfoList waiters_;
  49
  50   DISALLOW_COPY_AND_ASSIGN(WaiterList);
  51 };
  52
  53 }  // namespace system
  54 }  // namespace mojo
  55
  56 #endif  // MOJO_SYSTEM_WAITER_LIST_H_