Quelle ReentrantMonitor.h Sprache: C

/* -*- 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_ReentrantMonitor_h
#define mozilla_ReentrantMonitor_h

#include "prmon.h"

#if defined(MOZILLA_INTERNAL_API) && !defined(DEBUG)
#  include "mozilla/ProfilerThreadSleep.h"
#endif  // defined( MOZILLA_INTERNAL_API) && !defined(DEBUG)

#include "mozilla/BlockingResourceBase.h"
#include "mozilla/ThreadSafety.h"
#include "nsISupports.h"
//
// Provides:
//
//  - ReentrantMonitor, a Java-like monitor
//  - ReentrantMonitorAutoEnter, an RAII class for ensuring that
//    ReentrantMonitors are properly entered and exited
//
// Using ReentrantMonitorAutoEnter is MUCH preferred to making bare calls to
// ReentrantMonitor.Enter and Exit.
//
namespace mozilla {

/**
* ReentrantMonitor
* Java-like monitor.
* When possible, use ReentrantMonitorAutoEnter to hold this monitor within a
* scope, instead of calling Enter/Exit directly.
**/
class MOZ_CAPABILITY("reentrant monitor") ReentrantMonitor
    : BlockingResourceBase {
public:
  /**
   * ReentrantMonitor
   * @param aName A name which can reference this monitor
   */
  explicit ReentrantMonitor(const char* aName)
      : BlockingResourceBase(aName, eReentrantMonitor)
#ifdef DEBUG
        ,
        mEntryCount(0)
#endif
  {
    MOZ_COUNT_CTOR(ReentrantMonitor);
    mReentrantMonitor = PR_NewMonitor();
    if (!mReentrantMonitor) {
      MOZ_CRASH("Can't allocate mozilla::ReentrantMonitor");
    }
  }

  /**
   * ~ReentrantMonitor
   **/
  ~ReentrantMonitor() {
    NS_ASSERTION(mReentrantMonitor,
                 "improperly constructed ReentrantMonitor or double free");
    PR_DestroyMonitor(mReentrantMonitor);
    mReentrantMonitor = 0;
    MOZ_COUNT_DTOR(ReentrantMonitor);
  }

#ifndef DEBUG
  /**
   * Enter
   * @see prmon.h
   **/
  void Enter() MOZ_CAPABILITY_ACQUIRE() { PR_EnterMonitor(mReentrantMonitor); }

  /**
   * Exit
   * @see prmon.h
   **/
  void Exit() MOZ_CAPABILITY_RELEASE() { PR_ExitMonitor(mReentrantMonitor); }

  /**
   * Wait
   * @see prmon.h
   **/
  nsresult Wait(PRIntervalTime aInterval = PR_INTERVAL_NO_TIMEOUT) {
    PR_ASSERT_CURRENT_THREAD_IN_MONITOR(mReentrantMonitor);
#  ifdef MOZILLA_INTERNAL_API
    AUTO_PROFILER_THREAD_SLEEP;
#  endif  // MOZILLA_INTERNAL_API
    return PR_Wait(mReentrantMonitor, aInterval) == PR_SUCCESS
               ? NS_OK
               : NS_ERROR_FAILURE;
  }

#else  // ifndef DEBUG
  void Enter() MOZ_CAPABILITY_ACQUIRE();
  void Exit() MOZ_CAPABILITY_RELEASE();
  nsresult Wait(PRIntervalTime aInterval = PR_INTERVAL_NO_TIMEOUT);

#endif  // ifndef DEBUG

  /**
   * Notify
   * @see prmon.h
   **/
  nsresult Notify() {
    return PR_Notify(mReentrantMonitor) == PR_SUCCESS ? NS_OK
                                                      : NS_ERROR_FAILURE;
  }

  /**
   * NotifyAll
   * @see prmon.h
   **/
  nsresult NotifyAll() {
    return PR_NotifyAll(mReentrantMonitor) == PR_SUCCESS ? NS_OK
                                                         : NS_ERROR_FAILURE;
  }

#ifdef DEBUG
  /**
   * AssertCurrentThreadIn
   * @see prmon.h
   **/
  void AssertCurrentThreadIn() MOZ_ASSERT_CAPABILITY(this) {
    PR_ASSERT_CURRENT_THREAD_IN_MONITOR(mReentrantMonitor);
  }

  /**
   * AssertNotCurrentThreadIn
   * @see prmon.h
   **/
  void AssertNotCurrentThreadIn() MOZ_ASSERT_CAPABILITY(!this) {
    // FIXME bug 476536
  }

#else
  void AssertCurrentThreadIn() MOZ_ASSERT_CAPABILITY(this) {}
  void AssertNotCurrentThreadIn() MOZ_ASSERT_CAPABILITY(!this) {}

#endif  // ifdef DEBUG

private:
  ReentrantMonitor();
  ReentrantMonitor(const ReentrantMonitor&);
  ReentrantMonitor& operator=(const ReentrantMonitor&);

  PRMonitor* mReentrantMonitor;
#ifdef DEBUG
  int32_t mEntryCount;
#endif
};

/**
* ReentrantMonitorAutoEnter
* Enters the ReentrantMonitor when it enters scope, and exits it when
* it leaves scope.
*
* MUCH PREFERRED to bare calls to ReentrantMonitor.Enter and Exit.
*/
class MOZ_SCOPED_CAPABILITY MOZ_STACK_CLASS ReentrantMonitorAutoEnter {
public:
  /**
   * Constructor
   * The constructor aquires the given lock.  The destructor
   * releases the lock.
   *
   * @param aReentrantMonitor A valid mozilla::ReentrantMonitor*.
   **/
  explicit ReentrantMonitorAutoEnter(
      mozilla::ReentrantMonitor& aReentrantMonitor)
      MOZ_CAPABILITY_ACQUIRE(aReentrantMonitor)
      : mReentrantMonitor(&aReentrantMonitor) {
    NS_ASSERTION(mReentrantMonitor, "null monitor");
    mReentrantMonitor->Enter();
  }

  ~ReentrantMonitorAutoEnter(void) MOZ_CAPABILITY_RELEASE() {
    mReentrantMonitor->Exit();
  }

  nsresult Wait(PRIntervalTime aInterval = PR_INTERVAL_NO_TIMEOUT) {
    return mReentrantMonitor->Wait(aInterval);
  }

  nsresult Notify() { return mReentrantMonitor->Notify(); }
  nsresult NotifyAll() { return mReentrantMonitor->NotifyAll(); }

private:
  ReentrantMonitorAutoEnter();
  ReentrantMonitorAutoEnter(const ReentrantMonitorAutoEnter&);
  ReentrantMonitorAutoEnter& operator=(const ReentrantMonitorAutoEnter&);
  static void* operator new(size_t) noexcept(true);

  friend class ReentrantMonitorAutoExit;

  mozilla::ReentrantMonitor* mReentrantMonitor;
};

/**
* ReentrantMonitorAutoExit
* Exit the ReentrantMonitor when it enters scope, and enters it when it leaves
* scope.
*
* MUCH PREFERRED to bare calls to ReentrantMonitor.Exit and Enter.
*/
class MOZ_SCOPED_CAPABILITY MOZ_STACK_CLASS ReentrantMonitorAutoExit {
public:
  /**
   * Constructor
   * The constructor releases the given lock.  The destructor
   * acquires the lock. The lock must be held before constructing
   * this object!
   *
   * @param aReentrantMonitor A valid mozilla::ReentrantMonitor*. It
   *                 must be already locked.
   **/
  explicit ReentrantMonitorAutoExit(ReentrantMonitor& aReentrantMonitor)
      MOZ_EXCLUSIVE_RELEASE(aReentrantMonitor)
      : mReentrantMonitor(&aReentrantMonitor) {
    NS_ASSERTION(mReentrantMonitor, "null monitor");
    mReentrantMonitor->AssertCurrentThreadIn();
    mReentrantMonitor->Exit();
  }

  explicit ReentrantMonitorAutoExit(
      ReentrantMonitorAutoEnter& aReentrantMonitorAutoEnter)
      MOZ_EXCLUSIVE_RELEASE(aReentrantMonitorAutoEnter.mReentrantMonitor)
      : mReentrantMonitor(aReentrantMonitorAutoEnter.mReentrantMonitor) {
    NS_ASSERTION(mReentrantMonitor, "null monitor");
    mReentrantMonitor->AssertCurrentThreadIn();
    mReentrantMonitor->Exit();
  }

  ~ReentrantMonitorAutoExit(void) MOZ_EXCLUSIVE_RELEASE() {
    mReentrantMonitor->Enter();
  }

private:
  ReentrantMonitorAutoExit();
  ReentrantMonitorAutoExit(const ReentrantMonitorAutoExit&);
  ReentrantMonitorAutoExit& operator=(const ReentrantMonitorAutoExit&);
  static void* operator new(size_t) noexcept(true);

  ReentrantMonitor* mReentrantMonitor;
};

}  // namespace mozilla

#endif  // ifndef mozilla_ReentrantMonitor_h

quality99%

¤ Dauer der Verarbeitung: 0.16 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.