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Diffstat (limited to 'base/condition_variable_posix.cc')
-rw-r--r-- | base/condition_variable_posix.cc | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/base/condition_variable_posix.cc b/base/condition_variable_posix.cc new file mode 100644 index 0000000..e234ece --- /dev/null +++ b/base/condition_variable_posix.cc @@ -0,0 +1,85 @@ +// Copyright 2008, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "base/condition_variable.h" + +#include <errno.h> +#include <sys/time.h> + +#include "base/lock.h" +#include "base/lock_impl.h" +#include "base/logging.h" + +ConditionVariable::ConditionVariable(Lock* user_lock) + : user_mutex_(user_lock->lock_impl()->os_lock()) { + int rv = pthread_cond_init(&condition_, NULL); + DCHECK(rv == 0); +} + +ConditionVariable::~ConditionVariable() { + int rv = pthread_cond_destroy(&condition_); + DCHECK(rv == 0); +} + +void ConditionVariable::Wait() { + int rv = pthread_cond_wait(&condition_, user_mutex_); + DCHECK(rv == 0); +} + +void ConditionVariable::TimedWait(const TimeDelta& max_time) { + int64 usecs = max_time.InMicroseconds(); + + // The timeout argument to pthread_cond_timedwait is in absolute time. + struct timeval now; + gettimeofday(&now, NULL); + + const int kMicrosPerUnit = 1000000; + const int kNanosPerMicro = 1000; + const int kNanosPerUnit = kMicrosPerUnit * kNanosPerMicro; + + struct timespec abstime; + abstime.tv_sec = now.tv_sec + (usecs / kMicrosPerUnit); + abstime.tv_nsec = (now.tv_usec + (usecs % kMicrosPerUnit)) * kNanosPerMicro; + abstime.tv_sec += abstime.tv_nsec / kNanosPerUnit; + abstime.tv_nsec %= kNanosPerUnit; + DCHECK(abstime.tv_sec >= now.tv_sec); // Overflow paranoia + + int rv = pthread_cond_timedwait(&condition_, user_mutex_, &abstime); + DCHECK(rv == 0 || rv == ETIMEDOUT); +} + +void ConditionVariable::Broadcast() { + int rv = pthread_cond_broadcast(&condition_); + DCHECK(rv == 0); +} + +void ConditionVariable::Signal() { + int rv = pthread_cond_signal(&condition_); + DCHECK(rv == 0); +} |