Add new files for HARP3

Host ATM Research Platform (HARP), Network Computing Services, Inc.
This software was developed with the support of the Defense Advanced
Research Projects Agency (DARPA).

1 files changed, 261 insertions, 0 deletions

diff --git a/lib/libatm/timer.c b/lib/libatm/timer.c
new file mode 100644
index 0000000..fc8b64f
--- /dev/null
+++ b/lib/libatm/timer.c
@@ -0,0 +1,261 @@
+/*
+ *
+ * ===================================
+ * HARP  |  Host ATM Research Platform
+ * ===================================
+ *
+ *
+ * This Host ATM Research Platform ("HARP") file (the "Software") is
+ * made available by Network Computing Services, Inc. ("NetworkCS")
+ * "AS IS".  NetworkCS does not provide maintenance, improvements or
+ * support of any kind.
+ *
+ * NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
+ * INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
+ * SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
+ * In no event shall NetworkCS be responsible for any damages, including
+ * but not limited to consequential damages, arising from or relating to
+ * any use of the Software or related support.
+ *
+ * Copyright 1994-1998 Network Computing Services, Inc.
+ *
+ * Copies of this Software may be made, however, the above copyright
+ * notice must be reproduced on all copies.
+ *
+ *	@(#) $Id: timer.c,v 1.4 1998/07/16 15:50:26 johnc Exp $
+ *
+ */
+
+/*
+ * User Space Library Functions
+ * ----------------------------
+ *
+ * Timer functions
+ *
+ */
+
+#ifndef lint
+static char *RCSid = "@(#) $Id: timer.c,v 1.4 1998/07/16 15:50:26 johnc Exp $";
+#endif
+
+#include <sys/types.h>
+#include <sys/param.h>
+
+#include <errno.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <netatm/port.h>
+#include <netatm/queue.h>
+#include <netatm/atm.h>
+#include <netatm/atm_if.h>
+#include <netatm/atm_sap.h>
+#include <netatm/atm_sys.h>
+#include <netatm/atm_ioctl.h>
+
+#include "libatm.h"
+
+Harp_timer	*harp_timer_head;
+int		harp_timer_exec;
+
+
+/*
+ * Process a HARP timer tick
+ *
+ * This function is called via the SIGALRM signal.  It increments
+ * harp_timer_exec.  The user should check this flag frequently and
+ * call timer_proc when it is set.
+ *
+ * Arguments:
+ *	None
+ *
+ * Returns:
+ *	None
+ *
+ */
+static void
+timer_tick()
+{
+	/*
+	 * Bump the timer flag
+	 */
+	harp_timer_exec++;
+}
+
+
+/*
+ * Process HARP timers
+ *
+ * This function is called after a SIGALRM signal is posted.  It runs
+ * down the list of timer entries, calling the specified functions
+ * for any timers that have expired.
+ *
+ * Arguments:
+ *	None
+ *
+ * Returns:
+ *	None
+ *
+ */
+void
+timer_proc()
+{
+	Harp_timer	*htp;
+	void		(*f)();
+
+	/*
+	 * Reset marks in all timers on the queue
+	 */
+	for (htp = harp_timer_head; htp; htp = htp->ht_next) {
+		htp->ht_mark = -1;
+	}
+
+	/*
+	 * Run through timer chain decrementing each timer.
+	 * If an expired timer is found, take the timer block
+	 * off the chain and call the specified function.  A
+	 * timer's action can result in other timers being
+	 * cancelled (taken off the queue), so every time we
+	 * call a user function, we start over from the top of
+	 * the list.
+	 */
+timer_cont:
+	for (htp = harp_timer_head; htp; htp = htp->ht_next) {
+		/*
+		 * Make sure we only process each entry once and
+		 * don't process entries that are put on the queue
+		 * by user functions we call for this tick
+		 */
+		if (htp->ht_mark == -1) {
+			/*
+			 * Decrement the timer and mark that we've
+			 * processed the entry
+			 */
+			htp->ht_ticks -= harp_timer_exec;
+			htp->ht_mark = 1;
+
+			/*
+			 * Check whether the timer is expired
+			 */
+			if (htp->ht_ticks <= 0) {
+				/*
+				 * Unlink the timer block and call
+				 * the user function
+				 */
+				f = htp->ht_func;
+				UNLINK(htp, Harp_timer, harp_timer_head,
+						ht_next);
+				f(htp);
+
+				/*
+				 * Start over
+				 */
+				goto timer_cont;
+			}
+		}
+	}
+
+	/*
+	 * Reset the timer exec flag
+	 */
+	harp_timer_exec = 0;
+}
+
+
+/*
+ * Start the timer
+ *
+ * Set up the SIGALRM signal handler and set up the real-time
+ * timer to tick once per second.
+ *
+ * Arguments:
+ *	None
+ *
+ * Returns:
+ *	0	success
+ *	errno	reason for failure
+ *
+ */
+int
+init_timer()
+{
+	int			rc = 0;
+	struct itimerval	timeval;
+
+	/*
+	 * Clear the timer flag
+	 */
+	harp_timer_exec = 0;
+
+	/*
+	 * Set up signal handler
+	 */
+	if ((int)signal(SIGALRM, timer_tick) == -1) {
+		return(errno);
+	}
+
+	/*
+	 * Start timer
+	 */
+	timeval.it_value.tv_sec = 1;
+	timeval.it_value.tv_usec = 0;
+	timeval.it_interval.tv_sec = 1;
+	timeval.it_interval.tv_usec = 0;
+
+	if (setitimer(ITIMER_REAL, &timeval,
+			(struct itimerval *)0) == -1) {
+		rc = errno;
+		(void)signal(SIGALRM, SIG_DFL);
+	}
+
+	return(rc);
+}
+
+
+/*
+ * Block timers from firing
+ *
+ * Block the SIGALRM signal.
+ *
+ * Arguments:
+ *	None
+ *
+ * Returns:
+ *	mask	the previous blocked signal mask
+ *
+ */
+int
+block_timer()
+{
+	/*
+	 * Block the SIGALRM signal
+	 */
+	return(sigblock(sigmask(SIGALRM)));
+}
+
+
+/*
+ * Re-enable timers
+ *
+ * Restore the signal mask (presumably one that was returned by
+ * block_timer).
+ *
+ * Arguments:
+ *	mask	the signal mask to be restored
+ *
+ * Returns:
+ *	mask	the previous blocked signal mask
+ *
+ */
+void
+enable_timer(mask)
+	int	mask;
+{
+	/*
+	 * Set the signal mask
+	 */
+	sigsetmask(mask);
+
+	return;
+}