diff options
Diffstat (limited to 'distrib/sdl-1.2.15/src/thread/os2/SDL_syssem.c')
| -rw-r--r-- | distrib/sdl-1.2.15/src/thread/os2/SDL_syssem.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/distrib/sdl-1.2.15/src/thread/os2/SDL_syssem.c b/distrib/sdl-1.2.15/src/thread/os2/SDL_syssem.c new file mode 100644 index 0000000..d6dfba6 --- /dev/null +++ b/distrib/sdl-1.2.15/src/thread/os2/SDL_syssem.c @@ -0,0 +1,192 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2012 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" + +/* Semaphore functions using the OS/2 API */ + +#define INCL_DOS +#define INCL_DOSERRORS +#define INCL_DOSSEMAPHORES +#include <os2.h> + +#include "SDL_thread.h" +#include "SDL_timer.h" + + +struct SDL_semaphore { + HMTX id; + HEV changed; + Uint32 value; +}; + + +/* Create a semaphore */ +DECLSPEC SDL_sem * SDLCALL SDL_CreateSemaphore(Uint32 initial_value) +{ + SDL_sem *sem; + ULONG ulrc; + + /* Allocate sem memory */ + sem = (SDL_sem *)SDL_malloc(sizeof(*sem)); + if ( sem ) { + /* Create the mutex semaphore */ + ulrc = DosCreateMutexSem(NULL,&(sem->id),0,TRUE); + if ( ulrc ) { + SDL_SetError("Couldn't create semaphore"); + SDL_free(sem); + sem = NULL; + } else + { + DosCreateEventSem(NULL, &(sem->changed), 0, FALSE); + sem->value = initial_value; + DosReleaseMutexSem(sem->id); + } + } else { + SDL_OutOfMemory(); + } + return(sem); +} + +/* Free the semaphore */ +DECLSPEC void SDLCALL SDL_DestroySemaphore(SDL_sem *sem) +{ + if ( sem ) { + if ( sem->id ) { + DosCloseEventSem(sem->changed); + DosCloseMutexSem(sem->id); + sem->id = 0; + } + SDL_free(sem); + } +} + +DECLSPEC int SDLCALL SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) +{ + ULONG ulrc; + + if ( ! sem ) { + SDL_SetError("Passed a NULL sem"); + return -1; + } + + if ( timeout == SDL_MUTEX_MAXWAIT ) { + while (1) { + ulrc = DosRequestMutexSem(sem->id, SEM_INDEFINITE_WAIT); + if (ulrc) { + /* if error waiting mutex */ + SDL_SetError("DosRequestMutexSem() failed"); + return -1; + } else if (sem->value) { + sem->value--; + DosReleaseMutexSem(sem->id); + return 0; + } else { + ULONG ulPostCount; + DosResetEventSem(sem->changed, &ulPostCount); + DosReleaseMutexSem(sem->id); + /* continue waiting until somebody posts the semaphore */ + DosWaitEventSem(sem->changed, SEM_INDEFINITE_WAIT); + } + } + } else + if ( timeout == 0 ) + { + ulrc = DosRequestMutexSem(sem->id, SEM_INDEFINITE_WAIT); + if (ulrc==NO_ERROR) + { + if (sem->value) + { + sem->value--; + DosReleaseMutexSem(sem->id); + return 0; + } else + { + DosReleaseMutexSem(sem->id); + return SDL_MUTEX_TIMEDOUT; + } + } else + { + SDL_SetError("DosRequestMutexSem() failed"); + return -1; + } + } else { + ulrc = DosRequestMutexSem(sem->id, SEM_INDEFINITE_WAIT); + if (ulrc) { + /* if error waiting mutex */ + SDL_SetError("DosRequestMutexSem() failed"); + return -1; + } else + if (sem->value) { + sem->value--; + DosReleaseMutexSem(sem->id); + return 0; + } else { + ULONG ulPostCount; + DosResetEventSem(sem->changed, &ulPostCount); + DosReleaseMutexSem(sem->id); + /* continue waiting until somebody posts the semaphore */ + ulrc = DosWaitEventSem(sem->changed, timeout); + if (ulrc==NO_ERROR) + return 0; + else + return SDL_MUTEX_TIMEDOUT; + } + } + /* never reached */ + return -1; +} + +DECLSPEC int SDLCALL SDL_SemTryWait(SDL_sem *sem) +{ + return SDL_SemWaitTimeout(sem, 0); +} + +DECLSPEC int SDLCALL SDL_SemWait(SDL_sem *sem) +{ + return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT); +} + +/* Returns the current count of the semaphore */ +DECLSPEC Uint32 SDLCALL SDL_SemValue(SDL_sem *sem) +{ + if ( ! sem ) { + SDL_SetError("Passed a NULL sem"); + return 0; + } + return sem->value; +} + +DECLSPEC int SDLCALL SDL_SemPost(SDL_sem *sem) +{ + if ( ! sem ) { + SDL_SetError("Passed a NULL sem"); + return -1; + } + if ( DosRequestMutexSem(sem->id,SEM_INDEFINITE_WAIT) ) { + SDL_SetError("DosRequestMutexSem() failed"); + return -1; + } + sem->value++; + DosPostEventSem(sem->changed); + DosReleaseMutexSem(sem->id); + return 0; +} |