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Diffstat (limited to '')
-rw-r--r-- | thread.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/thread.c b/thread.c new file mode 100644 index 0000000..86673ba --- /dev/null +++ b/thread.c @@ -0,0 +1,169 @@ +/* $Id: thread.c,v 1.1 2004/03/19 06:37:47 reinelt Exp $ + * + * thread handling (mutex, shmem, ...) + * + * Copyright 2004 Michael Reinelt <reinelt@eunet.at> + * Copyright 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net> + * + * parts of this code are based on the old XWindow driver which is + * Copyright 2000 Herbert Rosmanith <herp@wildsau.idv.uni-linz.ac.at> + * + * This file is part of LCD4Linux. + * + * LCD4Linux 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; either version 2, or (at your option) + * any later version. + * + * LCD4Linux 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * + * $Log: thread.c,v $ + * Revision 1.1 2004/03/19 06:37:47 reinelt + * asynchronous thread handling started + * + */ + +/* + * exported functions: + * + * Fixme: document me! + * + */ + + +#include "config.h" + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <signal.h> +#include <sys/types.h> +#include <sys/ipc.h> +#include <sys/sem.h> +#include <sys/shm.h> + +#include "debug.h" +#include "thread.h" + + +#ifdef WITH_DMALLOC +#include <dmalloc.h> +#endif + + +/* glibc 2.1 requires defining semun ourselves */ +#ifdef _SEM_SEMUN_UNDEFINED +union semun { + int val; + struct semid_ds *buf; + unsigned short int *array; + struct seminfo *__buf; +}; +#endif + + +int mutex_create (void) +{ + int semid; + union semun semun; + + semid = semget(IPC_PRIVATE, 1, 0); + if (semid == -1) { + error ("fatal error: semget() failed: %s", strerror(errno)); + return -1; + } + semun.val = 1; + semctl(semid, 0, SETVAL, semun); + + return semid; +} + + +void mutex_lock (int semid) +{ + struct sembuf sembuf; + sembuf.sem_num = 0; + sembuf.sem_op = -1; + sembuf.sem_flg = 0; + semop (semid, &sembuf, 1); +} + + +void mutex_unlock (int semid) +{ + struct sembuf sembuf; + sembuf.sem_num = 0; + sembuf.sem_op = 1; + sembuf.sem_flg = 0; + semop (semid, &sembuf, 1); +} + + +void mutex_destroy (int semid) +{ + union semun arg; + semctl(semid, 0, IPC_RMID, arg); +} + + +int shm_create (void **buffer, int size) +{ + int shmid; + + shmid = shmget(IPC_PRIVATE, size, SHM_R|SHM_W); + if (shmid==-1) { + error ("fatal error: shmget() failed: %s", strerror(errno)); + return -1; + } + + *buffer = shmat(shmid, NULL, 0); + if (*buffer == NULL) { + error ("fatal error: shmat() failed: %s", strerror(errno)); + return -1; + } + + return shmid; +} + + +void shm_destroy (int shmid) +{ + shmctl(shmid, IPC_RMID, NULL); +} + + +int thread_create (void (*thread)(void)) +{ + /* + ppid=getpid(); + + switch(async_updater_pid=fork()) { + case -1: + error ("X11: fork() failed: %s", strerror(errno)); + return -1; + + case 0: + async_update(); + error ("X11: async_update failed"); + kill(ppid,SIGTERM); + exit(-1); + + default: + break; + } + + signal(SIGCHLD,quit_updater); + atexit(quit_updater); + */ + return 0; +} |