gecko-dev/mozglue/misc/Mutex_posix.cpp

94 строки
3.0 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 <errno.h>
#include <pthread.h>
#include <stdio.h>
#include "mozilla/PlatformMutex.h"
#include "MutexPlatformData_posix.h"
#define TRY_CALL_PTHREADS(call, msg) \
{ \
int result = (call); \
if (result != 0) { \
errno = result; \
perror(msg); \
MOZ_CRASH(msg); \
} \
}
mozilla::detail::MutexImpl::MutexImpl()
{
pthread_mutexattr_t* attrp = nullptr;
// Linux with glibc and FreeBSD support adaptive mutexes that spin
// for a short number of tries before sleeping. NSPR's locks did
// this, too, and it seems like a reasonable thing to do.
#if (defined(__linux__) && defined(__GLIBC__)) || defined(__FreeBSD__)
#define ADAPTIVE_MUTEX_SUPPORTED
#endif
#if defined(DEBUG)
#define ATTR_REQUIRED
#define MUTEX_KIND PTHREAD_MUTEX_ERRORCHECK
#elif defined(ADAPTIVE_MUTEX_SUPPORTED)
#define ATTR_REQUIRED
#define MUTEX_KIND PTHREAD_MUTEX_ADAPTIVE_NP
#endif
#if defined(ATTR_REQUIRED)
pthread_mutexattr_t attr;
TRY_CALL_PTHREADS(pthread_mutexattr_init(&attr),
"mozilla::detail::MutexImpl::MutexImpl: pthread_mutexattr_init failed");
TRY_CALL_PTHREADS(pthread_mutexattr_settype(&attr, MUTEX_KIND),
"mozilla::detail::MutexImpl::MutexImpl: pthread_mutexattr_settype failed");
attrp = &attr;
#endif
TRY_CALL_PTHREADS(pthread_mutex_init(&platformData()->ptMutex, attrp),
"mozilla::detail::MutexImpl::MutexImpl: pthread_mutex_init failed");
#if defined(ATTR_REQUIRED)
TRY_CALL_PTHREADS(pthread_mutexattr_destroy(&attr),
"mozilla::detail::MutexImpl::MutexImpl: pthread_mutexattr_destroy failed");
#endif
}
mozilla::detail::MutexImpl::~MutexImpl()
{
TRY_CALL_PTHREADS(pthread_mutex_destroy(&platformData()->ptMutex),
"mozilla::detail::MutexImpl::~MutexImpl: pthread_mutex_destroy failed");
}
void
mozilla::detail::MutexImpl::lock()
{
TRY_CALL_PTHREADS(pthread_mutex_lock(&platformData()->ptMutex),
"mozilla::detail::MutexImpl::lock: pthread_mutex_lock failed");
}
void
mozilla::detail::MutexImpl::unlock()
{
TRY_CALL_PTHREADS(pthread_mutex_unlock(&platformData()->ptMutex),
"mozilla::detail::MutexImpl::unlock: pthread_mutex_unlock failed");
}
#undef TRY_CALL_PTHREADS
mozilla::detail::MutexImpl::PlatformData*
mozilla::detail::MutexImpl::platformData()
{
static_assert(sizeof(platformData_) >= sizeof(PlatformData),
"platformData_ is too small");
return reinterpret_cast<PlatformData*>(platformData_);
}