DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (9b7cd94eaf0a)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115
/* -*- 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 xpcom_build_IOInterposerPrivate_h
#define xpcom_build_IOInterposerPrivate_h

/* This header file contains declarations for helper classes that are
   to be used exclusively by IOInterposer and its observers. This header
   file is not to be used by anything else and MUST NOT be exported! */

#include <prcvar.h>
#include <prlock.h>

namespace mozilla {
namespace IOInterposer {

/**
 * The following classes are simple wrappers for PRLock and PRCondVar.
 * IOInterposer and friends use these instead of Mozilla::Mutex et al because
 * of the fact that IOInterposer is permitted to run until the process
 * terminates; we can't use anything that plugs into leak checkers or deadlock
 * detectors because IOInterposer will outlive those and generate false
 * positives.
 */

class Monitor {
 public:
  Monitor() : mLock(PR_NewLock()), mCondVar(PR_NewCondVar(mLock)) {}

  ~Monitor() {
    PR_DestroyCondVar(mCondVar);
    mCondVar = nullptr;
    PR_DestroyLock(mLock);
    mLock = nullptr;
  }

  void Lock() { PR_Lock(mLock); }

  void Unlock() { PR_Unlock(mLock); }

  bool Wait(PRIntervalTime aTimeout = PR_INTERVAL_NO_TIMEOUT) {
    return PR_WaitCondVar(mCondVar, aTimeout) == PR_SUCCESS;
  }

  bool Notify() { return PR_NotifyCondVar(mCondVar) == PR_SUCCESS; }

 private:
  PRLock* mLock;
  PRCondVar* mCondVar;
};

class MonitorAutoLock {
 public:
  explicit MonitorAutoLock(Monitor& aMonitor) : mMonitor(aMonitor) {
    mMonitor.Lock();
  }

  ~MonitorAutoLock() { mMonitor.Unlock(); }

  bool Wait(PRIntervalTime aTimeout = PR_INTERVAL_NO_TIMEOUT) {
    return mMonitor.Wait(aTimeout);
  }

  bool Notify() { return mMonitor.Notify(); }

 private:
  Monitor& mMonitor;
};

class MonitorAutoUnlock {
 public:
  explicit MonitorAutoUnlock(Monitor& aMonitor) : mMonitor(aMonitor) {
    mMonitor.Unlock();
  }

  ~MonitorAutoUnlock() { mMonitor.Lock(); }

 private:
  Monitor& mMonitor;
};

class Mutex {
 public:
  Mutex() : mPRLock(PR_NewLock()) {}

  ~Mutex() {
    PR_DestroyLock(mPRLock);
    mPRLock = nullptr;
  }

  void Lock() { PR_Lock(mPRLock); }

  void Unlock() { PR_Unlock(mPRLock); }

 private:
  PRLock* mPRLock;
};

class AutoLock {
 public:
  explicit AutoLock(Mutex& aLock) : mLock(aLock) { mLock.Lock(); }

  ~AutoLock() { mLock.Unlock(); }

 private:
  Mutex& mLock;
};

}  // namespace IOInterposer
}  // namespace mozilla

#endif  // xpcom_build_IOInterposerPrivate_h