michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=8 sts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "mozilla/Assertions.h"
michael@0: #include "mozilla/DebugOnly.h"
michael@0: #include "mozilla/NullPtr.h"
michael@0: 
michael@0: #include "LulRWLock.h"
michael@0: 
michael@0: 
michael@0: namespace lul {
michael@0: 
michael@0: // An implementation for targets where libpthread does provide
michael@0: // pthread_rwlock_t.  These are straight wrappers around the
michael@0: // equivalent pthread functions.
michael@0: 
michael@0: #if defined(LUL_OS_linux)
michael@0: 
michael@0: LulRWLock::LulRWLock() {
michael@0:   mozilla::DebugOnly<int> r = pthread_rwlock_init(&mLock, nullptr);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: LulRWLock::~LulRWLock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_rwlock_destroy(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: void
michael@0: LulRWLock::WrLock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_rwlock_wrlock(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: void
michael@0: LulRWLock::RdLock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_rwlock_rdlock(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: void
michael@0: LulRWLock::Unlock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_rwlock_unlock(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: 
michael@0: // An implementation for cases where libpthread does not provide
michael@0: // pthread_rwlock_t.  Currently this is a kludge in that it uses
michael@0: // normal mutexes, resulting in the following limitations: (1) at most
michael@0: // one reader is allowed at once, and (2) any thread that tries to
michael@0: // read-acquire the lock more than once will deadlock.  (2) could be
michael@0: // avoided if it were possible to use recursive pthread_mutex_t's.
michael@0: 
michael@0: #elif defined(LUL_OS_android)
michael@0: 
michael@0: LulRWLock::LulRWLock() {
michael@0:   mozilla::DebugOnly<int> r = pthread_mutex_init(&mLock, nullptr);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: LulRWLock::~LulRWLock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_mutex_destroy(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: void
michael@0: LulRWLock::WrLock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_mutex_lock(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: void
michael@0: LulRWLock::RdLock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_mutex_lock(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: void
michael@0: LulRWLock::Unlock() {
michael@0:   mozilla::DebugOnly<int>r = pthread_mutex_unlock(&mLock);
michael@0:   MOZ_ASSERT(!r);
michael@0: }
michael@0: 
michael@0: 
michael@0: #else
michael@0: # error "Unsupported OS"
michael@0: #endif
michael@0: 
michael@0: } // namespace lul