mozglue/misc/PlatformConditionVariable.h
author Gerald Squelart <gsquelart@mozilla.com>
Thu, 04 Jul 2019 04:38:16 +0000
changeset 481213 8fed7bc35767fdfab4bac0908ae9b21c08f49e1f
parent 465997 9fa7ed12ba262d47c6d565887d25387775815dc9
child 510807 2aa57942649806333b9273bf13fb40f1dbfdb3da
permissions -rw-r--r--
Bug 1559000 - mozglue's AutoProfilerLabel doesn't need to know about ProfilingStack - r=mstange `ProfilingStack*` happens to be the information that the current Gecko Profiler entry function wants to forward to the exit function, but AutoProfilerLabel does not really need to know about that. Changing it to `void*`, so that we can later use different entry/exit functions that use different context types. Differential Revision: https://phabricator.services.mozilla.com/D34806

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_ConditionVariable_h
#define mozilla_ConditionVariable_h

#include "mozilla/Attributes.h"
#include "mozilla/Move.h"
#include "mozilla/PlatformMutex.h"
#include "mozilla/TimeStamp.h"

#include <stdint.h>
#ifndef XP_WIN
#  include <pthread.h>
#endif

namespace mozilla {

enum class CVStatus { NoTimeout, Timeout };

namespace detail {

class ConditionVariableImpl {
 public:
  struct PlatformData;

  MFBT_API ConditionVariableImpl();
  MFBT_API ~ConditionVariableImpl();

  // Wake one thread that is waiting on this condition.
  MFBT_API void notify_one();

  // Wake all threads that are waiting on this condition.
  MFBT_API void notify_all();

  // Atomically release |lock| and sleep the current thread of execution on
  // this condition variable.
  // |lock| will be re-acquired before this function returns.
  // The thread may be woken from sleep from another thread via notify_one()
  // or notify_all(), but may also wake spuriously.  The caller should recheck
  // its predicate after this function returns, typically in a while loop.
  MFBT_API void wait(MutexImpl& lock);

  MFBT_API CVStatus wait_for(MutexImpl& lock,
                             const mozilla::TimeDuration& rel_time);

 private:
  ConditionVariableImpl(const ConditionVariableImpl&) = delete;
  ConditionVariableImpl& operator=(const ConditionVariableImpl&) = delete;

  PlatformData* platformData();

#ifndef XP_WIN
  void* platformData_[sizeof(pthread_cond_t) / sizeof(void*)];
  static_assert(sizeof(pthread_cond_t) / sizeof(void*) != 0 &&
                    sizeof(pthread_cond_t) % sizeof(void*) == 0,
                "pthread_cond_t must have pointer alignment");
#else
  void* platformData_[4];
#endif
};

}  // namespace detail

}  // namespace mozilla

#endif  // mozilla_ConditionVariable_h