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/time.h" 13 14 namespace base { 15 16 ConditionVariable::ConditionVariable(Lock* user_lock) 17 : user_mutex_(user_lock->lock_.os_lock()) 18 #if !defined(NDEBUG) 19 , user_lock_(user_lock) 20 #endif 21 { 22 int rv = pthread_cond_init(&condition_, NULL); 23 DCHECK_EQ(0, rv); 24 } 25 26 ConditionVariable::~ConditionVariable() { 27 int rv = pthread_cond_destroy(&condition_); 28 DCHECK_EQ(0, rv); 29 } 30 31 void ConditionVariable::Wait() { 32 #if !defined(NDEBUG) 33 user_lock_->CheckHeldAndUnmark(); 34 #endif 35 int rv = pthread_cond_wait(&condition_, user_mutex_); 36 DCHECK_EQ(0, rv); 37 #if !defined(NDEBUG) 38 user_lock_->CheckUnheldAndMark(); 39 #endif 40 } 41 42 void ConditionVariable::TimedWait(const TimeDelta& max_time) { 43 int64 usecs = max_time.InMicroseconds(); 44 45 // The timeout argument to pthread_cond_timedwait is in absolute time. 46 struct timeval now; 47 gettimeofday(&now, NULL); 48 49 struct timespec abstime; 50 abstime.tv_sec = now.tv_sec + (usecs / Time::kMicrosecondsPerSecond); 51 abstime.tv_nsec = (now.tv_usec + (usecs % Time::kMicrosecondsPerSecond)) * 52 Time::kNanosecondsPerMicrosecond; 53 abstime.tv_sec += abstime.tv_nsec / Time::kNanosecondsPerSecond; 54 abstime.tv_nsec %= Time::kNanosecondsPerSecond; 55 DCHECK_GE(abstime.tv_sec, now.tv_sec); // Overflow paranoia 56 57 #if !defined(NDEBUG) 58 user_lock_->CheckHeldAndUnmark(); 59 #endif 60 int rv = pthread_cond_timedwait(&condition_, user_mutex_, &abstime); 61 DCHECK(rv == 0 || rv == ETIMEDOUT); 62 #if !defined(NDEBUG) 63 user_lock_->CheckUnheldAndMark(); 64 #endif 65 } 66 67 void ConditionVariable::Broadcast() { 68 int rv = pthread_cond_broadcast(&condition_); 69 DCHECK_EQ(0, rv); 70 } 71 72 void ConditionVariable::Signal() { 73 int rv = pthread_cond_signal(&condition_); 74 DCHECK_EQ(0, rv); 75 } 76 77 } // namespace base 78
