gecko-dev/tools/profiler/LulRWLock.cpp

94 строки
2.2 KiB
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/. */
#include "mozilla/Assertions.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/NullPtr.h"
#include "LulRWLock.h"
namespace lul {
// An implementation for targets where libpthread does provide
// pthread_rwlock_t. These are straight wrappers around the
// equivalent pthread functions.
#if defined(LUL_OS_linux)
LulRWLock::LulRWLock() {
mozilla::DebugOnly<int> r = pthread_rwlock_init(&mLock, nullptr);
MOZ_ASSERT(!r);
}
LulRWLock::~LulRWLock() {
mozilla::DebugOnly<int>r = pthread_rwlock_destroy(&mLock);
MOZ_ASSERT(!r);
}
void
LulRWLock::WrLock() {
mozilla::DebugOnly<int>r = pthread_rwlock_wrlock(&mLock);
MOZ_ASSERT(!r);
}
void
LulRWLock::RdLock() {
mozilla::DebugOnly<int>r = pthread_rwlock_rdlock(&mLock);
MOZ_ASSERT(!r);
}
void
LulRWLock::Unlock() {
mozilla::DebugOnly<int>r = pthread_rwlock_unlock(&mLock);
MOZ_ASSERT(!r);
}
// An implementation for cases where libpthread does not provide
// pthread_rwlock_t. Currently this is a kludge in that it uses
// normal mutexes, resulting in the following limitations: (1) at most
// one reader is allowed at once, and (2) any thread that tries to
// read-acquire the lock more than once will deadlock. (2) could be
// avoided if it were possible to use recursive pthread_mutex_t's.
#elif defined(LUL_OS_android)
LulRWLock::LulRWLock() {
mozilla::DebugOnly<int> r = pthread_mutex_init(&mLock, nullptr);
MOZ_ASSERT(!r);
}
LulRWLock::~LulRWLock() {
mozilla::DebugOnly<int>r = pthread_mutex_destroy(&mLock);
MOZ_ASSERT(!r);
}
void
LulRWLock::WrLock() {
mozilla::DebugOnly<int>r = pthread_mutex_lock(&mLock);
MOZ_ASSERT(!r);
}
void
LulRWLock::RdLock() {
mozilla::DebugOnly<int>r = pthread_mutex_lock(&mLock);
MOZ_ASSERT(!r);
}
void
LulRWLock::Unlock() {
mozilla::DebugOnly<int>r = pthread_mutex_unlock(&mLock);
MOZ_ASSERT(!r);
}
#else
# error "Unsupported OS"
#endif
} // namespace lul