[lcd4linux @ 2004-01-13 08:18:07 by reinelt]

timer queues added
liblcd4linux deactivated turing transformation to new layout

git-svn-id: https://ssl.bulix.org/svn/lcd4linux/trunk@308 3ae390bd-cb1e-0410-b409-cd5a39f66f1f

1 files changed, 178 insertions, 0 deletions

diff --git a/timer.c b/timer.c
new file mode 100644
index 0000000..f85998d
--- /dev/null
+++ b/timer.c
@@ -0,0 +1,178 @@
+/* $Id: timer.c,v 1.1 2004/01/13 08:18:20 reinelt Exp $
+ *
+ * generic timer handling
+ *
+ * Copyright 2003,2004 Michael Reinelt <reinelt@eunet.at>
+ * Copyright 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
+ *
+ * This program 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.
+ *
+ * This program 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: timer.c,v $
+ * Revision 1.1  2004/01/13 08:18:20  reinelt
+ * timer queues added
+ * liblcd4linux deactivated turing transformation to new layout
+ *
+ */
+
+/* 
+ * exported functions:
+ *
+ * int timer_junk(void)
+ *   Fixme: document me :-(
+ *
+ */
+
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include "debug.h"
+#include "cfg.h"
+#include "timer.h"
+
+
+typedef struct TIMER {
+  void (*callback)(void *data);
+  void  *data;
+  struct timeval when;
+  int interval;
+  int one_shot;
+  int active;
+} TIMER;
+
+
+TIMER *Timers=NULL;
+int   nTimers=0;
+
+
+static void timer_inc (struct timeval *tv, int msec)
+{
+  tv->tv_sec  +=  msec                     / 1000;
+  tv->tv_usec += (msec - 1000*(msec/1000)) * 1000;
+  
+  if (tv->tv_usec >= 1000000) {
+    tv->tv_usec -= 1000000;
+    tv->tv_sec++;
+  }
+}
+
+
+int timer_add (void (*callback)(void *data), void *data, int interval, int one_shot)
+{
+  int i;
+  struct timeval now;
+  
+  gettimeofday(&now, NULL);
+  
+  // find a free slot
+  for (i=0; i<nTimers; i++) {
+    if (Timers[i].active==0) break;
+  }
+
+  // none found, allocate a new slot
+  if (i>=nTimers) {
+    nTimers++;
+    Timers=realloc(Timers, nTimers*sizeof(*Timers));
+  }
+  
+  // fill slot
+  Timers[i].callback = callback;
+  Timers[i].data     = data;
+  Timers[i].when     = now;
+  Timers[i].interval = interval;
+  Timers[i].one_shot = one_shot;
+  Timers[i].active   = 1;
+
+  // if one-shot timer, don't fire now
+  if (one_shot) {
+    timer_inc (&Timers[i].when, interval);
+  }
+  
+  return 0;
+}
+
+
+int timer_process (struct timespec *delay)
+{
+  int i, flag, min;
+  struct timeval now;
+  
+  // the current moment
+  gettimeofday(&now, NULL);
+
+  // sanity check
+  if (nTimers==0) {
+    error ("huh? not one single timer to process? dazed and confused...");
+    return -1;
+  }
+
+  // process expired timers
+  flag=0;
+  for (i=0; i<nTimers; i++) {
+    if (Timers[i].active == 0) continue;
+    if (timercmp(&Timers[i].when, &now, <=)) {
+      flag=1;
+      // callback
+      if (Timers[i].callback!=NULL) {
+	Timers[i].callback(Timers[i].data);
+      }
+      // respawn or delete timer
+      if (Timers[i].one_shot) {
+	Timers[i].active=0;
+      } else {
+	Timers[i].when=now;
+	timer_inc (&Timers[i].when, Timers[i].interval);
+      }
+    }
+  }
+
+  if (flag) {
+    // Fixme: if at least one timer has been processed, do a flush()
+    
+  }
+
+  // find next timer
+  flag=1;
+  min=-1;
+  for (i=0; i<nTimers; i++) {
+    if (Timers[i].active == 0) continue;
+    if (flag || timercmp(&Timers[i].when, &Timers[min].when, <)) {
+      flag=0;
+      min=i;
+    }
+  }
+  
+  if (min<0) {
+    error ("huh? not one single timer left? dazed and confused...");
+    return -1;
+  }
+    
+  // delay until next timer event
+  delay->tv_sec   = Timers[min].when.tv_sec  - now.tv_sec;
+  delay->tv_nsec  = Timers[min].when.tv_usec - now.tv_usec;
+  if (delay->tv_nsec<0) {
+    delay->tv_sec--;
+    delay->tv_nsec += 1000000;
+  }
+  // nanoseconds!!
+  delay->tv_nsec *= 1000;
+
+  return 0;
+  
+}