src/thread/thread_os2.cpp

   1 /* $Id: thread_os2.cpp 26353 2014-02-18 17:58:46Z frosch $ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   6  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   7  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   8  */
   9
  10 /** @file thread_os2.cpp OS/2 implementation of Threads. */
  11
  12 #include "../stdafx.h"
  13 #include "thread.h"
  14
  15 #define INCL_DOS
  16 #include <os2.h>
  17 #include <process.h>
  18
  19 #include "../safeguards.h"
  20
  21 /**
  22  * OS/2 version for ThreadObject.
  23  */
  24 class ThreadObject_OS2 : public ThreadObject {
  25 private:
  26         TID thread;          ///< System thread identifier.
  27         OTTDThreadFunc proc; ///< External thread procedure.
  28         void *param;         ///< Parameter for the external thread procedure.
  29         bool self_destruct;  ///< Free ourselves when done?
  30
  31 public:
  32         /**
  33          * Create a thread and start it, calling proc(param).
  34          */
  35         ThreadObject_OS2(OTTDThreadFunc proc, void *param, bool self_destruct) :
  36                 thread(0),
  37                 proc(proc),
  38                 param(param),
  39                 self_destruct(self_destruct)
  40         {
  41                 thread = _beginthread(stThreadProc, NULL, 1048576, this);
  42         }
  43
  44         /* virtual */ bool Exit()
  45         {
  46                 _endthread();
  47                 return true;
  48         }
  49
  50         /* virtual */ void Join()
  51         {
  52                 DosWaitThread(&this->thread, DCWW_WAIT);
  53                 this->thread = 0;
  54         }
  55 private:
  56         /**
  57          * On thread creation, this function is called, which calls the real startup
  58          *  function. This to get back into the correct instance again.
  59          */
  60         static void stThreadProc(void *thr)
  61         {
  62                 ((ThreadObject_OS2 *)thr)->ThreadProc();
  63         }
  64
  65         /**
  66          * A new thread is created, and this function is called. Call the custom
  67          *  function of the creator of the thread.
  68          */
  69         void ThreadProc()
  70         {
  71                 /* Call the proc of the creator to continue this thread */
  72                 try {
  73                         this->proc(this->param);
  74                 } catch (OTTDThreadExitSignal e) {
  75                 } catch (...) {
  76                         NOT_REACHED();
  77                 }
  78
  79                 if (self_destruct) {
  80                         this->Exit();
  81                         delete this;
  82                 }
  83         }
  84 };
  85
  86 /* static */ bool ThreadObject::New(OTTDThreadFunc proc, void *param, ThreadObject **thread, const char *name)
  87 {
  88         ThreadObject *to = new ThreadObject_OS2(proc, param, thread == NULL);
  89         if (thread != NULL) *thread = to;
  90         return true;
  91 }
  92
  93 /**
  94  * OS/2 version of ThreadMutex.
  95  */
  96 class ThreadMutex_OS2 : public ThreadMutex {
  97 private:
  98         HMTX mutex; ///< The mutex.
  99         HEV event;  ///< Event for waiting.
 100         uint recursive_count;     ///< Recursive lock count.
 101
 102 public:
 103         ThreadMutex_OS2() : recursive_count(0)
 104         {
 105                 DosCreateMutexSem(NULL, &mutex, 0, FALSE);
 106                 DosCreateEventSem(NULL, &event, 0, FALSE);
 107         }
 108
 109         /* virtual */ ~ThreadMutex_OS2()
 110         {
 111                 DosCloseMutexSem(mutex);
 112                 DosCloseEventSem(event);
 113         }
 114
 115         /* virtual */ void BeginCritical(bool allow_recursive = false)
 116         {
 117                 /* os2 mutex is recursive by itself */
 118                 DosRequestMutexSem(mutex, (unsigned long) SEM_INDEFINITE_WAIT);
 119                 this->recursive_count++;
 120                 if (!allow_recursive && this->recursive_count != 1) NOT_REACHED();
 121         }
 122
 123         /* virtual */ void EndCritical(bool allow_recursive = false)
 124         {
 125                 if (!allow_recursive && this->recursive_count != 1) NOT_REACHED();
 126                 this->recursive_count--;
 127                 DosReleaseMutexSem(mutex);
 128         }
 129
 130         /* virtual */ void WaitForSignal()
 131         {
 132                 assert(this->recursive_count == 1); // Do we need to call Begin/EndCritical multiple times otherwise?
 133                 this->EndCritical();
 134                 DosWaitEventSem(event, SEM_INDEFINITE_WAIT);
 135                 this->BeginCritical();
 136         }
 137
 138         /* virtual */ void SendSignal()
 139         {
 140                 DosPostEventSem(event);
 141         }
 142 };
 143
 144 /* static */ ThreadMutex *ThreadMutex::New()
 145 {
 146         return new ThreadMutex_OS2();
 147 }