/*+
−
    SDL - Simple DirectMedia Layer+
−
    Copyright (C) 1997-2009 Sam Lantinga+
−
+
−
    This library is free software; you can redistribute it and/or+
−
    modify it under the terms of the GNU Lesser General Public+
−
    License as published by the Free Software Foundation; either+
−
    version 2.1 of the License, or (at your option) any later version.+
−
+
−
    This library 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.  See the GNU+
−
    Lesser General Public License for more details.+
−
+
−
    You should have received a copy of the GNU Lesser General Public+
−
    License along with this library; if not, write to the Free Software+
−
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA+
−
+
−
    Sam Lantinga+
−
    slouken@libsdl.org+
−
*/+
−
#include "SDL_config.h"+
−
+
−
/* Mutex functions using the OS/2 API */+
−
+
−
#define INCL_DOSERRORS+
−
#define INCL_DOSSEMAPHORES+
−
#include <os2.h>+
−
+
−
#include "SDL_mutex.h"+
−
+
−
+
−
struct SDL_mutex {+
−
	HMTX hmtxID;+
−
};+
−
+
−
/* Create a mutex */+
−
DECLSPEC SDL_mutex * SDLCALL SDL_CreateMutex(void)+
−
{+
−
  SDL_mutex *mutex;+
−
  APIRET ulrc;+
−
+
−
  /* Allocate mutex memory */+
−
  mutex = (SDL_mutex *)SDL_malloc(sizeof(*mutex));+
−
  if (mutex)+
−
  {+
−
    /* Create the mutex, with initial value signaled */+
−
    ulrc = DosCreateMutexSem(NULL,                  // Create unnamed semaphore+
−
                             &(mutex->hmtxID),      // Pointer to handle+
−
                             0L,                    // Flags: create it private (not shared)+
−
                             FALSE);                // Initial value: unowned+
−
    if (ulrc!=NO_ERROR)+
−
    {+
−
      SDL_SetError("Couldn't create mutex");+
−
      SDL_free(mutex);+
−
      mutex = NULL;+
−
    }+
−
  } else {+
−
    SDL_OutOfMemory();+
−
  }+
−
  return(mutex);+
−
}+
−
+
−
/* Free the mutex */+
−
DECLSPEC void SDLCALL SDL_DestroyMutex(SDL_mutex *mutex)+
−
{+
−
  if ( mutex )+
−
  {+
−
    if ( mutex->hmtxID )+
−
    {+
−
      DosCloseMutexSem(mutex->hmtxID);+
−
      mutex->hmtxID = 0;+
−
    }+
−
    SDL_free(mutex);+
−
  }+
−
}+
−
+
−
/* Lock the mutex */+
−
DECLSPEC int SDLCALL SDL_mutexP(SDL_mutex *mutex)+
−
{+
−
  if ( mutex == NULL )+
−
  {+
−
    SDL_SetError("Passed a NULL mutex");+
−
    return -1;+
−
  }+
−
  if ( DosRequestMutexSem(mutex->hmtxID, SEM_INDEFINITE_WAIT) != NO_ERROR )+
−
  {+
−
    SDL_SetError("Couldn't wait on mutex");+
−
    return -1;+
−
  }+
−
  return(0);+
−
}+
−
+
−
/* Unlock the mutex */+
−
DECLSPEC int SDLCALL SDL_mutexV(SDL_mutex *mutex)+
−
{+
−
  if ( mutex == NULL )+
−
  {+
−
    SDL_SetError("Passed a NULL mutex");+
−
    return -1;+
−
  }+
−
  if ( DosReleaseMutexSem(mutex->hmtxID) != NO_ERROR )+
−
  {+
−
    SDL_SetError("Couldn't release mutex");+
−
    return -1;+
−
  }+
−
  return(0);+
−
}+
−