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/* -*- 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/. */

#include "mozilla/RecursiveMutex.h"

#ifdef XP_WIN
#  include <windows.h>

#  define NativeHandle(m) (reinterpret_cast<CRITICAL_SECTION*>(&m))
#endif

namespace mozilla {

RecursiveMutex::RecursiveMutex(const char* aName)
    : BlockingResourceBase(aName, eRecursiveMutex)
#ifdef DEBUG
      ,
      mOwningThread(nullptr),
      mEntryCount(0)
#endif
{
#ifdef XP_WIN
  // This number was adapted from NSPR.
  static const DWORD sLockSpinCount = 100;

#  if defined(RELEASE_OR_BETA)
  // Vista and later automatically allocate and subsequently leak a debug info
  // object for each critical section that we allocate unless we tell the
  // system not to do that.
  DWORD flags = CRITICAL_SECTION_NO_DEBUG_INFO;
#  else
  DWORD flags = 0;
#  endif
  BOOL r =
      InitializeCriticalSectionEx(NativeHandle(mMutex), sLockSpinCount, flags);
  MOZ_RELEASE_ASSERT(r);
#else
  pthread_mutexattr_t attr;

  MOZ_RELEASE_ASSERT(pthread_mutexattr_init(&attr) == 0,
                     "pthread_mutexattr_init failed");

  MOZ_RELEASE_ASSERT(
      pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE) == 0,
      "pthread_mutexattr_settype failed");

  MOZ_RELEASE_ASSERT(pthread_mutex_init(&mMutex, &attr) == 0,
                     "pthread_mutex_init failed");

  MOZ_RELEASE_ASSERT(pthread_mutexattr_destroy(&attr) == 0,
                     "pthread_mutexattr_destroy failed");
#endif
}

RecursiveMutex::~RecursiveMutex() {
#ifdef XP_WIN
  DeleteCriticalSection(NativeHandle(mMutex));
#else
  MOZ_RELEASE_ASSERT(pthread_mutex_destroy(&mMutex) == 0,
                     "pthread_mutex_destroy failed");
#endif
}

void RecursiveMutex::LockInternal() {
#ifdef XP_WIN
  EnterCriticalSection(NativeHandle(mMutex));
#else
  MOZ_RELEASE_ASSERT(pthread_mutex_lock(&mMutex) == 0,
                     "pthread_mutex_lock failed");
#endif
}

void RecursiveMutex::UnlockInternal() {
#ifdef XP_WIN
  LeaveCriticalSection(NativeHandle(mMutex));
#else
  MOZ_RELEASE_ASSERT(pthread_mutex_unlock(&mMutex) == 0,
                     "pthread_mutex_unlock failed");
#endif
}

}  // namespace mozilla