framework/delibs/decpp/deThread.cpp

   1 /*-------------------------------------------------------------------------
   2  * drawElements C++ Base Library
   3  * -----------------------------
   4  *
   5  * Copyright 2014 The Android Open Source Project
   6  *
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  *
  19  *//*!
  20  * \file
  21  * \brief Thread base class.
  22  *//*--------------------------------------------------------------------*/
  23
  24 #include "deThread.hpp"
  25 #include "deMemory.h"
  26
  27 #include <exception>
  28 #include <stdexcept>
  29 #include <new>
  30
  31 namespace de
  32 {
  33
  34 /*--------------------------------------------------------------------*//*!
  35  * \brief Thread constructor.
  36  *//*--------------------------------------------------------------------*/
  37 Thread::Thread (void)
  38         : m_thread(0)
  39 {
  40         deMemset(&m_attribs, 0, sizeof(m_attribs));
  41 }
  42
  43 /*--------------------------------------------------------------------*//*!
  44  * \brief Destroy thread.
  45  *
  46  * If the thread is currently running, OS is instructed to destroy it
  47  * but the actual behavior is unspecified.
  48  *//*--------------------------------------------------------------------*/
  49 Thread::~Thread (void)
  50 {
  51         if (m_thread)
  52                 deThread_destroy(m_thread);
  53 }
  54
  55 /*--------------------------------------------------------------------*//*!
  56  * \brief Set thread priority.
  57  * \param priority deThreadPriority as described in deThread.h. Currently
  58  *                                 supported values are: DE_THREADPRIORITY_LOWEST,
  59  *                                 DE_THREADPRIORITY_LOW, DE_THREADPRIORITY_NORMAL,
  60  *                                 DE_THREADPRIORITY_HIGH, DE_THREADPRIORITY_HIGHEST.
  61  *
  62  * Sets priority for the thread start(). setPriority() has no effect
  63  * if the thread is already running.
  64  *//*--------------------------------------------------------------------*/
  65 void Thread::setPriority (deThreadPriority priority)
  66 {
  67         m_attribs.priority = priority;
  68 }
  69
  70 static void threadFunc (void* arg)
  71 {
  72         static_cast<Thread*>(arg)->run();
  73 }
  74
  75 /*--------------------------------------------------------------------*//*!
  76  * \brief Start thread.
  77  *
  78  * Starts thread that will execute the virtual run() method.
  79  *
  80  * The function will fail if the thread is currently running or has finished
  81  * but no join() has been called.
  82  *//*--------------------------------------------------------------------*/
  83 void Thread::start (void)
  84 {
  85         DE_ASSERT(!m_thread);
  86         m_thread = deThread_create(threadFunc, this, &m_attribs);
  87         if (!m_thread)
  88                 throw std::bad_alloc();
  89 }
  90
  91 /*--------------------------------------------------------------------*//*!
  92  * \brief Wait for thread to finish and clean up current thread.
  93  *
  94  * This function will block until currently running thread has finished.
  95  * Once the thread has finished, current thread state will be cleaned
  96  * and thread can be re-launched using start().
  97  *
  98  * join() can only be called after a successful call to start().
  99  *//*--------------------------------------------------------------------*/
 100 void Thread::join (void)
 101 {
 102         DE_ASSERT(m_thread);
 103         if (!deThread_join(m_thread))
 104                 throw std::runtime_error("Thread::join() failed");
 105
 106         deThread_destroy(m_thread);
 107         m_thread = 0;
 108 }
 109
 110 } // de