src/lib/platform/posix/pthreads.cpp

   1 /*
   2  * This file is part of the libCEC(R) library.
   3  *
   4  * libCEC(R) is Copyright (C) 2011 Pulse-Eight Limited.  All rights reserved.
   5  * libCEC(R) is an original work, containing original code.
   6  *
   7  * libCEC(R) is a trademark of Pulse-Eight Limited.
   8  *
   9  * This program is dual-licensed; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  *
  23  *
  24  * Alternatively, you can license this library under a commercial license,
  25  * please contact Pulse-Eight Licensing for more information.
  26  *
  27  * For more information contact:
  28  * Pulse-Eight Licensing       <license@pulse-eight.com>
  29  *     http://www.pulse-eight.com/
  30  *     http://www.pulse-eight.net/
  31  */
  32
  33 #include "../threads.h"
  34 #include "../timeutils.h"
  35
  36 using namespace CEC;
  37
  38 CMutex::CMutex(bool bRecursive /* = true */) :
  39     IMutex(bRecursive)
  40 {
  41   pthread_mutex_init(&m_mutex, bRecursive ? GetMutexAttribute() : NULL);
  42 }
  43
  44 CMutex::~CMutex(void)
  45 {
  46   pthread_mutex_destroy(&m_mutex);
  47 }
  48
  49 bool CMutex::TryLock(void)
  50 {
  51   return (pthread_mutex_trylock(&m_mutex) == 0);
  52 }
  53
  54 bool CMutex::Lock(void)
  55 {
  56   return (pthread_mutex_lock(&m_mutex) == 0);
  57 }
  58
  59 void CMutex::Unlock(void)
  60 {
  61   pthread_mutex_unlock(&m_mutex);
  62 }
  63
  64 static pthread_mutexattr_t g_mutexAttr;
  65 pthread_mutexattr_t *CMutex::GetMutexAttribute()
  66 {
  67   static bool bAttributeInitialised = false;
  68   if (!bAttributeInitialised)
  69   {
  70     pthread_mutexattr_init(&g_mutexAttr);
  71     pthread_mutexattr_settype(&g_mutexAttr, PTHREAD_MUTEX_RECURSIVE);
  72     bAttributeInitialised = true;
  73   }
  74   return &g_mutexAttr;
  75 }
  76
  77 CCondition::CCondition(void)
  78 {
  79   pthread_cond_init(&m_cond, NULL);
  80 }
  81
  82 CCondition::~CCondition(void)
  83 {
  84   pthread_cond_broadcast(&m_cond);
  85   pthread_cond_destroy(&m_cond);
  86 }
  87
  88 void CCondition::Broadcast(void)
  89 {
  90   pthread_cond_broadcast(&m_cond);
  91 }
  92
  93 void CCondition::Signal(void)
  94 {
  95   pthread_cond_signal(&m_cond);
  96 }
  97
  98 bool CCondition::Wait(IMutex *mutex, uint32_t iTimeout /* = 0 */)
  99 {
 100   bool bReturn(false);
 101   sched_yield();
 102   CMutex *pmutex = static_cast<CMutex *>(mutex);
 103   if (pmutex)
 104   {
 105     if (iTimeout > 0)
 106     {
 107       struct timespec abstime;
 108       struct timeval now;
 109       gettimeofday(&now, NULL);
 110       iTimeout       += now.tv_usec / 1000;
 111       abstime.tv_sec  = now.tv_sec + (time_t)(iTimeout / 1000);
 112       abstime.tv_nsec = (int32_t)((iTimeout % (uint32_t)1000) * (uint32_t)1000000);
 113       bReturn         = (pthread_cond_timedwait(&m_cond, &pmutex->m_mutex, &abstime) == 0);
 114     }
 115     else
 116     {
 117       bReturn         = (pthread_cond_wait(&m_cond, &pmutex->m_mutex) == 0);
 118     }
 119   }
 120   return bReturn;
 121 }
 122
 123 bool CThread::CreateThread(bool bWait /* = true */)
 124 {
 125   bool bReturn(false);
 126   CLockObject lock(m_threadMutex);
 127   m_bStop = false;
 128   if (!m_bRunning && pthread_create(&m_thread, NULL, (void *(*) (void *))&CThread::ThreadHandler, (void *)this) == 0)
 129   {
 130     if (bWait)
 131       m_threadCondition->Wait(m_threadMutex);
 132     bReturn = true;
 133   }
 134   return bReturn;
 135 }
 136
 137 bool CThread::StopThread(bool bWaitForExit /* = true */)
 138 {
 139   bool bReturn = IThread::StopThread(bWaitForExit);
 140
 141   void *retVal;
 142   if (bWaitForExit && m_bRunning)
 143     bReturn = (pthread_join(m_thread, &retVal) == 0);
 144
 145   return bReturn;
 146 }
 147
 148 void *CThread::ThreadHandler(CThread *thread)
 149 {
 150   void *retVal = NULL;
 151
 152   if (thread)
 153   {
 154     CLockObject lock(thread->m_threadMutex);
 155     thread->m_bRunning = true;
 156     lock.Leave();
 157     thread->m_threadCondition->Broadcast();
 158
 159     retVal = thread->Process();
 160
 161     lock.Lock();
 162     thread->m_bRunning = false;
 163     lock.Leave();
 164     thread->m_threadCondition->Broadcast();
 165   }
 166
 167   return retVal;
 168 }