src/lib/platform/threads.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(void)
  39 {
  40   pthread_mutex_init(&m_mutex, NULL);
  41 }
  42
  43 CMutex::~CMutex(void)
  44 {
  45   pthread_mutex_destroy(&m_mutex);
  46 }
  47
  48 bool CMutex::TryLock(void)
  49 {
  50   return (pthread_mutex_trylock(&m_mutex) == 0);
  51 }
  52
  53 bool CMutex::Lock(void)
  54 {
  55   return (pthread_mutex_lock(&m_mutex) == 0);
  56 }
  57
  58 void CMutex::Unlock(void)
  59 {
  60   pthread_mutex_unlock(&m_mutex);
  61 }
  62
  63 CLockObject::CLockObject(CMutex *mutex) :
  64   m_mutex(mutex)
  65 {
  66   if (m_mutex)
  67     m_mutex->Lock();
  68 }
  69
  70 CLockObject::~CLockObject(void)
  71 {
  72   Leave();
  73   m_mutex = NULL;
  74 }
  75
  76 void CLockObject::Leave(void)
  77 {
  78   if (m_mutex)
  79     m_mutex->Unlock();
  80 }
  81
  82 void CLockObject::Lock(void)
  83 {
  84   if (m_mutex)
  85     m_mutex->Lock();
  86 }
  87
  88 CCondition::CCondition(void)
  89 {
  90   pthread_cond_init(&m_cond, NULL);
  91 }
  92
  93 CCondition::~CCondition(void)
  94 {
  95   pthread_cond_broadcast(&m_cond);
  96   pthread_cond_destroy(&m_cond);
  97 }
  98
  99 void CCondition::Broadcast(void)
 100 {
 101   pthread_cond_broadcast(&m_cond);
 102 }
 103
 104 void CCondition::Signal(void)
 105 {
 106   pthread_cond_signal(&m_cond);
 107 }
 108
 109 bool CCondition::Wait(CMutex *mutex, uint32_t iTimeout)
 110 {
 111   bool bReturn(false);
 112   sched_yield();
 113   if (mutex)
 114   {
 115     struct timespec abstime;
 116     struct timeval now;
 117     gettimeofday(&now, NULL);
 118     iTimeout       += now.tv_usec / 1000;
 119     abstime.tv_sec  = now.tv_sec + (time_t)(iTimeout / 1000);
 120     abstime.tv_nsec = (int32_t)((iTimeout % (uint32_t)1000) * (uint32_t)1000000);
 121     bReturn         = (pthread_cond_timedwait(&m_cond, &mutex->m_mutex, &abstime) == 0);
 122   }
 123
 124   return bReturn;
 125 }
 126
 127 void CCondition::Sleep(uint32_t iTimeout)
 128 {
 129   CCondition w;
 130   CMutex m;
 131   CLockObject lock(&m);
 132   w.Wait(&m, iTimeout);
 133 }
 134
 135 CThread::CThread(void) :
 136     m_bRunning(false),
 137     m_bStop(false)
 138 {
 139 }
 140
 141 CThread::~CThread(void)
 142 {
 143   StopThread();
 144 }
 145
 146 bool CThread::CreateThread(void)
 147 {
 148   bool bReturn(false);
 149
 150   CLockObject lock(&m_threadMutex);
 151   m_bStop = false;
 152   if (!m_bRunning && pthread_create(&m_thread, NULL, (void *(*) (void *))&CThread::ThreadHandler, (void *)this) == 0)
 153   {
 154     m_bRunning = true;
 155     bReturn = true;
 156   }
 157
 158   return bReturn;
 159 }
 160
 161 void *CThread::ThreadHandler(CThread *thread)
 162 {
 163   void *retVal = NULL;
 164
 165   if (thread)
 166     retVal = thread->Process();
 167   thread->m_bRunning = false;
 168
 169   return retVal;
 170 }
 171
 172 bool CThread::StopThread(bool bWaitForExit /* = true */)
 173 {
 174   bool bReturn(false);
 175   m_bStop = true;
 176
 177   m_threadCondition.Broadcast();
 178   if (m_bRunning)
 179   {
 180     void *retVal;
 181     if (bWaitForExit)
 182       bReturn = (pthread_join(m_thread, &retVal) == 0);
 183
 184     m_bRunning = false;
 185   }
 186
 187   return bReturn;
 188 }
 189
 190 bool CThread::Sleep(uint32_t iTimeout)
 191 {
 192   CLockObject lock(&m_threadMutex);
 193   return m_bStop ? false :m_threadCondition.Wait(&m_threadMutex, iTimeout);
 194 }