[lcd4linux @ 2004-03-19 06:37:47 by reinelt]

asynchronous thread handling started

git-svn-id: https://ssl.bulix.org/svn/lcd4linux/trunk@403 3ae390bd-cb1e-0410-b409-cd5a39f66f1f

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;
+}