mojo/system/waiter_test_utils.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_TEST_UTILS_H_
   6 #define MOJO_SYSTEM_WAITER_TEST_UTILS_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/threading/simple_thread.h"
  12 #include "mojo/public/c/system/types.h"
  13 #include "mojo/system/dispatcher.h"
  14 #include "mojo/system/waiter.h"
  15
  16 namespace mojo {
  17 namespace system {
  18 namespace test {
  19
  20 // This is a very simple thread that has a |Waiter|, on which it waits
  21 // indefinitely (and records the result). It will create and initialize the
  22 // |Waiter| on creation, but the caller must start the thread with |Start()|. It
  23 // will join the thread on destruction.
  24 //
  25 // One usually uses it like:
  26 //
  27 //    MojoResult result;
  28 //    {
  29 //      WaiterList waiter_list;
  30 //      test::SimpleWaiterThread thread(&result);
  31 //      waiter_list.AddWaiter(thread.waiter(), ...);
  32 //      thread.Start();
  33 //      ... some stuff to wake the waiter ...
  34 //      waiter_list.RemoveWaiter(thread.waiter());
  35 //    }  // Join |thread|.
  36 //    EXPECT_EQ(..., result);
  37 //
  38 // There's a bit of unrealism in its use: In this sort of usage, calls such as
  39 // |Waiter::Init()|, |AddWaiter()|, and |RemoveWaiter()| are done in the main
  40 // (test) thread, not the waiter thread (as would actually happen in real code).
  41 // (We accept this unrealism for simplicity, since |WaiterList| is
  42 // thread-unsafe so making it more realistic would require adding nontrivial
  43 // synchronization machinery.)
  44 class SimpleWaiterThread : public base::SimpleThread {
  45  public:
  46   // For the duration of the lifetime of this object, |*result| belongs to it
  47   // (in the sense that it will write to it whenever it wants).
  48   explicit SimpleWaiterThread(MojoResult* result);
  49   virtual ~SimpleWaiterThread();  // Joins the thread.
  50
  51   Waiter* waiter() { return &waiter_; }
  52
  53  private:
  54   virtual void Run() OVERRIDE;
  55
  56   MojoResult* const result_;
  57   Waiter waiter_;
  58
  59   DISALLOW_COPY_AND_ASSIGN(SimpleWaiterThread);
  60 };
  61
  62 // This is a more complex and realistic thread that has a |Waiter|, on which it
  63 // waits for the given deadline (with the given flags). Unlike
  64 // |SimpleWaiterThread|, it requires the machinery of |Dispatcher|.
  65 class WaiterThread : public base::SimpleThread {
  66  public:
  67   // Note: |*did_wait_out| and |*result| belong to this object while it's alive.
  68   WaiterThread(scoped_refptr<Dispatcher> dispatcher,
  69                MojoWaitFlags wait_flags,
  70                MojoDeadline deadline,
  71                MojoResult success_result,
  72                bool* did_wait_out,
  73                MojoResult* result_out);
  74   virtual ~WaiterThread();
  75
  76  private:
  77   virtual void Run() OVERRIDE;
  78
  79   const scoped_refptr<Dispatcher> dispatcher_;
  80   const MojoWaitFlags wait_flags_;
  81   const MojoDeadline deadline_;
  82   const MojoResult success_result_;
  83   bool* const did_wait_out_;
  84   MojoResult* const result_out_;
  85
  86   Waiter waiter_;
  87
  88   DISALLOW_COPY_AND_ASSIGN(WaiterThread);
  89 };
  90
  91 }  // namespace test
  92 }  // namespace system
  93 }  // namespace mojo
  94
  95 #endif  // MOJO_SYSTEM_WAITER_TEST_UTILS_H_