494f20977e
This class is being used from both libjingle and webrtc but we recently had a regression when we added dependency on libjingle's Thread class. This cleans that up and moves the implementation of CriticalSection and helper classes into the source file. I'm also improving debugging facilities and constness. BUG= R=magjed@webrtc.org Review URL: https://webrtc-codereview.appspot.com/51769004 Cr-Commit-Position: refs/heads/master@{#9089}
156 lines
3.5 KiB
C++
156 lines
3.5 KiB
C++
/*
|
|
* Copyright 2015 The WebRTC Project Authors. All rights reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#include "webrtc/base/criticalsection.h"
|
|
|
|
#include "webrtc/base/checks.h"
|
|
|
|
namespace rtc {
|
|
|
|
CriticalSection::CriticalSection() {
|
|
#if defined(WEBRTC_WIN)
|
|
InitializeCriticalSection(&crit_);
|
|
#else
|
|
pthread_mutexattr_t mutex_attribute;
|
|
pthread_mutexattr_init(&mutex_attribute);
|
|
pthread_mutexattr_settype(&mutex_attribute, PTHREAD_MUTEX_RECURSIVE);
|
|
pthread_mutex_init(&mutex_, &mutex_attribute);
|
|
pthread_mutexattr_destroy(&mutex_attribute);
|
|
CS_DEBUG_CODE(thread_ = 0);
|
|
CS_DEBUG_CODE(recursion_count_ = 0);
|
|
#endif
|
|
}
|
|
|
|
CriticalSection::~CriticalSection() {
|
|
#if defined(WEBRTC_WIN)
|
|
DeleteCriticalSection(&crit_);
|
|
#else
|
|
pthread_mutex_destroy(&mutex_);
|
|
#endif
|
|
}
|
|
|
|
void CriticalSection::Enter() EXCLUSIVE_LOCK_FUNCTION() {
|
|
#if defined(WEBRTC_WIN)
|
|
EnterCriticalSection(&crit_);
|
|
#else
|
|
pthread_mutex_lock(&mutex_);
|
|
#if CS_DEBUG_CHECKS
|
|
if (!recursion_count_) {
|
|
DCHECK(!thread_);
|
|
thread_ = pthread_self();
|
|
} else {
|
|
DCHECK(CurrentThreadIsOwner());
|
|
}
|
|
++recursion_count_;
|
|
#endif
|
|
#endif
|
|
}
|
|
|
|
bool CriticalSection::TryEnter() EXCLUSIVE_TRYLOCK_FUNCTION(true) {
|
|
#if defined(WEBRTC_WIN)
|
|
return TryEnterCriticalSection(&crit_) != FALSE;
|
|
#else
|
|
if (pthread_mutex_trylock(&mutex_) != 0)
|
|
return false;
|
|
#if CS_DEBUG_CHECKS
|
|
if (!recursion_count_) {
|
|
DCHECK(!thread_);
|
|
thread_ = pthread_self();
|
|
} else {
|
|
DCHECK(CurrentThreadIsOwner());
|
|
}
|
|
++recursion_count_;
|
|
#endif
|
|
return true;
|
|
#endif
|
|
}
|
|
void CriticalSection::Leave() UNLOCK_FUNCTION() {
|
|
DCHECK(CurrentThreadIsOwner());
|
|
#if defined(WEBRTC_WIN)
|
|
LeaveCriticalSection(&crit_);
|
|
#else
|
|
#if CS_DEBUG_CHECKS
|
|
--recursion_count_;
|
|
DCHECK(recursion_count_ >= 0);
|
|
if (!recursion_count_)
|
|
thread_ = 0;
|
|
#endif
|
|
pthread_mutex_unlock(&mutex_);
|
|
#endif
|
|
}
|
|
|
|
bool CriticalSection::CurrentThreadIsOwner() const {
|
|
#if defined(WEBRTC_WIN)
|
|
return crit_.OwningThread == reinterpret_cast<HANDLE>(GetCurrentThreadId());
|
|
#else
|
|
#if CS_DEBUG_CHECKS
|
|
return pthread_equal(thread_, pthread_self());
|
|
#else
|
|
return true;
|
|
#endif // CS_DEBUG_CHECKS
|
|
#endif
|
|
}
|
|
|
|
bool CriticalSection::IsLocked() const {
|
|
#if defined(WEBRTC_WIN)
|
|
return crit_.LockCount != -1;
|
|
#else
|
|
#if CS_DEBUG_CHECKS
|
|
return thread_ != 0;
|
|
#else
|
|
return true;
|
|
#endif
|
|
#endif
|
|
}
|
|
|
|
CritScope::CritScope(CriticalSection* cs) : cs_(cs) { cs_->Enter(); }
|
|
CritScope::~CritScope() { cs_->Leave(); }
|
|
|
|
TryCritScope::TryCritScope(CriticalSection* cs)
|
|
: cs_(cs), locked_(cs->TryEnter()) {
|
|
CS_DEBUG_CODE(lock_was_called_ = false);
|
|
}
|
|
|
|
TryCritScope::~TryCritScope() {
|
|
CS_DEBUG_CODE(DCHECK(lock_was_called_));
|
|
if (locked_)
|
|
cs_->Leave();
|
|
}
|
|
|
|
bool TryCritScope::locked() const {
|
|
CS_DEBUG_CODE(lock_was_called_ = true);
|
|
return locked_;
|
|
}
|
|
|
|
void GlobalLockPod::Lock() {
|
|
#if !defined(WEBRTC_WIN)
|
|
const struct timespec ts_null = {0};
|
|
#endif
|
|
|
|
while (AtomicOps::CompareAndSwap(&lock_acquired, 0, 1)) {
|
|
#if defined(WEBRTC_WIN)
|
|
::Sleep(0);
|
|
#else
|
|
nanosleep(&ts_null, nullptr);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void GlobalLockPod::Unlock() {
|
|
int old_value = AtomicOps::CompareAndSwap(&lock_acquired, 1, 0);
|
|
DCHECK_EQ(1, old_value) << "Unlock called without calling Lock first";
|
|
}
|
|
|
|
GlobalLock::GlobalLock() {
|
|
lock_acquired = 0;
|
|
}
|
|
|
|
} // namespace rtc
|