1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "base/synchronization/condition_variable.h" 6 7 #include <errno.h> 8 #include <sys/time.h> 9 10 #include "base/logging.h" 11 #include "base/synchronization/lock.h" 12 #include "base/threading/thread_restrictions.h" 13 #include "base/time/time.h" 14 15 namespace base { 16 17 ConditionVariable::ConditionVariable(Lock* user_lock) 18 : user_mutex_(user_lock->lock_.os_lock()) 19 #if !defined(NDEBUG) 20 , user_lock_(user_lock) 21 #endif 22 { 23 int rv = pthread_cond_init(&condition_, NULL); 24 DCHECK_EQ(0, rv); 25 } 26 27 ConditionVariable::~ConditionVariable() { 28 int rv = pthread_cond_destroy(&condition_); 29 DCHECK_EQ(0, rv); 30 } 31 32 void ConditionVariable::Wait() { 33 base::ThreadRestrictions::AssertWaitAllowed(); 34 #if !defined(NDEBUG) 35 user_lock_->CheckHeldAndUnmark(); 36 #endif 37 int rv = pthread_cond_wait(&condition_, user_mutex_); 38 DCHECK_EQ(0, rv); 39 #if !defined(NDEBUG) 40 user_lock_->CheckUnheldAndMark(); 41 #endif 42 } 43 44 void ConditionVariable::TimedWait(const TimeDelta& max_time) { 45 base::ThreadRestrictions::AssertWaitAllowed(); 46 int64 usecs = max_time.InMicroseconds(); 47 48 // The timeout argument to pthread_cond_timedwait is in absolute time. 49 struct timeval now; 50 gettimeofday(&now, NULL); 51 52 struct timespec abstime; 53 abstime.tv_sec = now.tv_sec + (usecs / Time::kMicrosecondsPerSecond); 54 abstime.tv_nsec = (now.tv_usec + (usecs % Time::kMicrosecondsPerSecond)) * 55 Time::kNanosecondsPerMicrosecond; 56 abstime.tv_sec += abstime.tv_nsec / Time::kNanosecondsPerSecond; 57 abstime.tv_nsec %= Time::kNanosecondsPerSecond; 58 DCHECK_GE(abstime.tv_sec, now.tv_sec); // Overflow paranoia 59 60 #if !defined(NDEBUG) 61 user_lock_->CheckHeldAndUnmark(); 62 #endif 63 int rv = pthread_cond_timedwait(&condition_, user_mutex_, &abstime); 64 DCHECK(rv == 0 || rv == ETIMEDOUT); 65 #if !defined(NDEBUG) 66 user_lock_->CheckUnheldAndMark(); 67 #endif 68 } 69 70 void ConditionVariable::Broadcast() { 71 int rv = pthread_cond_broadcast(&condition_); 72 DCHECK_EQ(0, rv); 73 } 74 75 void ConditionVariable::Signal() { 76 int rv = pthread_cond_signal(&condition_); 77 DCHECK_EQ(0, rv); 78 } 79 80 } // namespace base 81
