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 <stdint.h>
   9
  10 #include <list>
  11
  12 #include "base/macros.h"
  13 #include "mojo/public/c/system/types.h"
  14 #include "mojo/system/system_impl_export.h"
  15
  16 namespace mojo {
  17 namespace system {
  18
  19 class Waiter;
  20 struct HandleSignalsState;
  21
  22 // |WaiterList| tracks all the |Waiter|s that are waiting on a given
  23 // handle/|Dispatcher|. There should be a |WaiterList| for each handle that can
  24 // be waited on (in any way). In the simple case, the |WaiterList| is owned by
  25 // the |Dispatcher|, whereas in more complex cases it is owned by the secondary
  26 // object (see simple_dispatcher.* and the explanatory comment in core.cc). This
  27 // class is thread-unsafe (all concurrent access must be protected by some
  28 // lock).
  29 class MOJO_SYSTEM_IMPL_EXPORT WaiterList {
  30  public:
  31   WaiterList();
  32   ~WaiterList();
  33
  34   void AwakeWaitersForStateChange(const HandleSignalsState& state);
  35   void CancelAllWaiters();
  36   void AddWaiter(Waiter* waiter, MojoHandleSignals signals, uint32_t context);
  37   void RemoveWaiter(Waiter* waiter);
  38
  39  private:
  40   struct WaiterInfo {
  41     WaiterInfo(Waiter* waiter, MojoHandleSignals signals, uint32_t context)
  42         : waiter(waiter), signals(signals), context(context) {}
  43
  44     Waiter* waiter;
  45     MojoHandleSignals signals;
  46     uint32_t context;
  47   };
  48   typedef std::list<WaiterInfo> WaiterInfoList;
  49
  50   WaiterInfoList waiters_;
  51
  52   DISALLOW_COPY_AND_ASSIGN(WaiterList);
  53 };
  54
  55 }  // namespace system
  56 }  // namespace mojo
  57
  58 #endif  // MOJO_SYSTEM_WAITER_LIST_H_