sync/posix/condition.hpp

0001 //////////////////////////////////////////////////////////////////////////////
0002 //
0003 // (C) Copyright Ion Gaztanaga 2005-2012. Distributed under the Boost
0004 // Software License, Version 1.0. (See accompanying file
0005 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 //
0007 // See http://www.boost.org/libs/interprocess for documentation.
0008 //
0009 //////////////////////////////////////////////////////////////////////////////
0010
0011 #ifndef BOOST_INTERPROCESS_POSIX_CONDITION_HPP
0012 #define BOOST_INTERPROCESS_POSIX_CONDITION_HPP
0013
0014 #ifndef BOOST_CONFIG_HPP
0015 #  include <boost/config.hpp>
0016 #endif
0017 0018 ">#
0019 #if defined(BOOST_HAS_PRAGMA_ONCE)
0020 #  pragma once
0021 #endif
0022
0023 #include <boost/interprocess/detail/config_begin.hpp>
0024 #include <boost/interprocess/detail/workaround.hpp>
0025
0026 #include <boost/interprocess/sync/cv_status.hpp>
0027 #include <pthread.h>
0028 #include <errno.h>
0029 #include <boost/interprocess/sync/posix/pthread_helpers.hpp>
0030 #include <boost/interprocess/sync/posix/timepoint_to_timespec.hpp>
0031 #include <boost/interprocess/timed_utils.hpp>
0032 #include <boost/interprocess/sync/posix/mutex.hpp>
0033 #include <boost/assert.hpp>
0034
0035 namespace boost {
0036 namespace interprocess {
0037 namespace ipcdetail {
0038
0039 class posix_condition
0040 {
0041    //Non-copyable
0042    posix_condition(const posix_condition &);
0043    posix_condition &operator=(const posix_condition &);
0044
0045    public:
0046    //!Constructs a posix_condition. On error throws interprocess_exception.
0047    posix_condition();
0048
0049    //!Destroys *this
0050    //!liberating system resources.
0051    ~posix_condition();
0052
0053    //!If there is a thread waiting on *this, change that
0054    //!thread's state to ready. Otherwise there is no effect.
0055    void notify_one();
0056
0057    //!Change the state of all threads waiting on *this to ready.
0058    //!If there are no waiting threads, notify_all() has no effect.
0059    void notify_all();
0060
0061    //!Releases the lock on the posix_mutex object associated with lock, blocks
0062    //!the current thread of execution until readied by a call to
0063    //!this->notify_one() or this->notify_all(), and then reacquires the lock.
0064    template <typename L>
0065    void wait(L& lock)
0066    {
0067       if (!lock)
0068          throw lock_exception();
0069       this->do_wait(*lock.mutex());
0070    }
0071
0072    //!The same as:
0073    //!while (!pred()) wait(lock)
0074    template <typename L, typename Pr>
0075    void wait(L& lock, Pr pred)
0076    {
0077       if (!lock)
0078          throw lock_exception();
0079
0080       while (!pred())
0081          this->do_wait(*lock.mutex());
0082    }
0083
0084    //!Releases the lock on the posix_mutex object associated with lock, blocks
0085    //!the current thread of execution until readied by a call to
0086    //!this->notify_one() or this->notify_all(), or until time abs_time is reached,
0087    //!and then reacquires the lock.
0088    //!Returns: false if time abs_time is reached, otherwise true.
0089    template <typename L, typename TimePoint>
0090    bool timed_wait(L& lock, const TimePoint &abs_time)
0091    {
0092       if (!lock)
0093          throw lock_exception();
0094       //Posix does not support infinity absolute time so handle it here
0095       if(ipcdetail::is_pos_infinity(abs_time)){
0096          this->wait(lock);
0097          return true;
0098       }
0099       return this->do_timed_wait(abs_time, *lock.mutex());
0100    }
0101
0102    //!The same as:   while (!pred()) {
0103    //!                  if (!timed_wait(lock, abs_time)) return pred();
0104    //!               } return true;
0105    template <typename L, typename TimePoint, typename Pr>
0106    bool timed_wait(L& lock, const TimePoint &abs_time, Pr pred)
0107    {
0108       if (!lock)
0109          throw lock_exception();
0110       //Posix does not support infinity absolute time so handle it here
0111       if(ipcdetail::is_pos_infinity(abs_time)){
0112          this->wait(lock, pred);
0113          return true;
0114       }
0115       while (!pred()){
0116          if (!this->do_timed_wait(abs_time, *lock.mutex()))
0117             return pred();
0118       }
0119       return true;
0120    }
0121
0122    //!Same as `timed_wait`, but this function is modeled after the
0123    //!standard library interface.
0124    template <typename L, class TimePoint>
0125    cv_status wait_until(L& lock, const TimePoint &abs_time)
0126    {  return this->timed_wait(lock, abs_time) ? cv_status::no_timeout : cv_status::timeout; }
0127
0128    //!Same as `timed_wait`, but this function is modeled after the
0129    //!standard library interface.
0130    template <typename L, class TimePoint, typename Pr>
0131    bool wait_until(L& lock, const TimePoint &abs_time, Pr pred)
0132    {  return this->timed_wait(lock, abs_time, pred); }
0133
0134    template <typename L, class Duration>
0135    cv_status wait_for(L& lock, const Duration &dur)
0136    {  return this->wait_until(lock, duration_to_ustime(dur)) ? cv_status::no_timeout : cv_status::timeout; }
0137
0138    template <typename L, class Duration, typename Pr>
0139    bool wait_for(L& lock, const Duration &dur, Pr pred)
0140    {  return this->wait_until(lock, duration_to_ustime(dur), pred); }
0141
0142    void do_wait(posix_mutex &mut);
0143
0144    template<class TimePoint>
0145    bool do_timed_wait(const TimePoint &abs_time, posix_mutex &mut);
0146
0147    private:
0148    pthread_cond_t   m_condition;
0149 };
0150
0151 inline posix_condition::posix_condition()
0152 {
0153    int res;
0154    pthread_condattr_t cond_attr;
0155    res = pthread_condattr_init(&cond_attr);
0156    if(res != 0){
0157       throw interprocess_exception("pthread_condattr_init failed");
0158    }
0159    res = pthread_condattr_setpshared(&cond_attr, PTHREAD_PROCESS_SHARED);
0160    if(res != 0){
0161       pthread_condattr_destroy(&cond_attr);
0162       throw interprocess_exception(res);
0163    }
0164    res = pthread_cond_init(&m_condition, &cond_attr);
0165    pthread_condattr_destroy(&cond_attr);
0166    if(res != 0){
0167       throw interprocess_exception(res);
0168    }
0169 }
0170
0171 inline posix_condition::~posix_condition()
0172 {
0173     int res = 0;
0174     res = pthread_cond_destroy(&m_condition);
0175     BOOST_ASSERT(res == 0); (void)res;
0176 }
0177
0178 inline void posix_condition::notify_one()
0179 {
0180     int res = 0;
0181     res = pthread_cond_signal(&m_condition);
0182     BOOST_ASSERT(res == 0); (void)res;
0183 }
0184
0185 inline void posix_condition::notify_all()
0186 {
0187     int res = 0;
0188     res = pthread_cond_broadcast(&m_condition);
0189     BOOST_ASSERT(res == 0); (void)res;
0190 }
0191
0192 inline void posix_condition::do_wait(posix_mutex &mut)
0193 {
0194    pthread_mutex_t* pmutex = &mut.m_mut;
0195    int res = 0;
0196    res = pthread_cond_wait(&m_condition, pmutex);
0197    BOOST_ASSERT(res == 0); (void)res;
0198 }
0199
0200 template<class TimePoint>
0201 inline bool posix_condition::do_timed_wait
0202    (const TimePoint &abs_time, posix_mutex &mut)
0203 {
0204    timespec ts = timepoint_to_timespec(abs_time);
0205    pthread_mutex_t* pmutex = &mut.m_mut;
0206    int res = 0;
0207    res = pthread_cond_timedwait(&m_condition, pmutex, &ts);
0208    BOOST_ASSERT(res == 0 || res == ETIMEDOUT);
0209
0210    return res != ETIMEDOUT;
0211 }
0212
0213 }  //namespace ipcdetail
0214 }  //namespace interprocess
0215 }  //namespace boost
0216
0217 #include <boost/interprocess/detail/config_end.hpp>
0218
0219 #endif   //#ifndef BOOST_INTERPROCESS_POSIX_CONDITION_HPP