Version 0.1.0 from FTP

git-svn-id: http://svn.digium.com/svn/asterisk/trunk@3 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 336 insertions, 0 deletions

diff --git a/sched.c b/sched.c
new file mode 100755
index 000000000..a6a2ca5d3
--- /dev/null
+++ b/sched.c
@@ -0,0 +1,336 @@
+/*
+ * Asterisk
+ * 
+ * Mark Spencer <markster@marko.net>
+ *
+ * Copyright(C) 1999, Adtran, Inc.
+ * 
+ * Distributed under the terms of the GNU General Public License (GPL) Version 2
+ *
+ * Scheduler Routines (form cheops-NG)
+ *
+ */
+
+#ifdef DEBUG_SCHEDULER
+#define DEBUG(a) DEBUG_M(a)
+#else
+#define DEBUG(a) 
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <asterisk/sched.h>
+#include <asterisk/logger.h>
+
+/* Determine if a is sooner than b */
+#define SOONER(a,b) (((b).tv_sec > (a).tv_sec) || \
+					 (((b).tv_sec == (a).tv_sec) && ((b).tv_usec > (a).tv_usec)))
+
+struct sched {
+	struct sched *next;				/* Next event in the list */
+	int id; 						/* ID number of event */
+	struct timeval when;			/* Absolute time event should take place */
+	int resched;					/* When to reschedule */
+	void *data; 					/* Data */
+	ast_sched_cb callback;		/* Callback */
+};
+
+struct sched_context {
+	/* Number of events processed */
+	int eventcnt;
+
+	/* Number of outstanding schedule events */
+	int schedcnt;
+
+	/* Schedule entry and main queue */
+ 	struct sched *schedq;
+
+#ifdef SCHED_MAX_CACHE
+	/* Cache of unused schedule structures and how many */
+	struct sched *schedc;
+	int schedccnt;
+#endif
+};
+
+struct sched_context *sched_context_create(void)
+{
+	struct sched_context *tmp;
+	tmp = malloc(sizeof(struct sched_context));
+	if (tmp) {
+		tmp->eventcnt = 1;
+		tmp->schedcnt = 0;
+		tmp->schedq = NULL;
+		tmp->schedc = NULL;
+		tmp->schedccnt = 0;
+	}
+	return tmp;
+}
+
+void sched_context_destroy(struct sched_context *con)
+{
+	struct sched *s, *sl;
+	/* Eliminate the cache */
+	s = con->schedc;
+	while(s) {
+		sl = s;
+		s = s->next;
+		free(sl);
+	}
+	/* And the queue */
+	s = con->schedq;
+	while(s) {
+		sl = s;
+		s = s->next;
+		free(sl);
+	}
+	/* And the context */
+	free(con);
+}
+
+static struct sched *sched_alloc(struct sched_context *con)
+{
+	/*
+	 * We keep a small cache of schedule entries
+	 * to minimize the number of necessary malloc()'s
+	 */
+	struct sched *tmp;
+#ifdef SCHED_MAX_CACHE
+	if (con->schedc) {
+		tmp = con->schedc;
+		con->schedc = con->schedc->next;
+		con->schedccnt--;
+	} else
+#endif
+		tmp = malloc(sizeof(struct sched));
+	return tmp;
+}
+
+static void sched_release(struct sched_context *con, struct sched *tmp)
+{
+	/*
+	 * Add to the cache, or just free() if we
+	 * already have too many cache entries
+	 */
+
+#ifdef SCHED_MAX_CACHE	 
+	if (con->schedccnt < SCHED_MAX_CACHE) {
+		tmp->next = con->schedc;
+		con->schedc = tmp;
+		con->schedccnt++;
+	} else
+#endif
+		free(tmp);
+}
+
+int ast_sched_wait(struct sched_context *con)
+{
+	/*
+	 * Return the number of milliseconds 
+	 * until the next scheduled event
+	 */
+	struct timeval tv;
+	int ms;
+	DEBUG(ast_log(LOG_DEBUG, "ast_sched_wait()\n"));
+	if (!con->schedq)
+		return -1;
+	if (gettimeofday(&tv, NULL) < 0) {
+		/* This should never happen */
+		return 0;
+	};
+	ms = (con->schedq->when.tv_sec - tv.tv_sec) * 1000;
+	ms += (con->schedq->when.tv_usec - tv.tv_usec) / 1000;
+	if (ms < 0)
+		ms = 0;
+	return ms;
+	
+}
+
+
+static void schedule(struct sched_context *con, struct sched *s)
+{
+	/*
+	 * Take a sched structure and put it in the
+	 * queue, such that the soonest event is
+	 * first in the list. 
+	 */
+	 
+	struct sched *last=NULL;
+	struct sched *current=con->schedq;
+	while(current) {
+		if (SOONER(s->when, current->when))
+			break;
+		last = current;
+		current = current->next;
+	}
+	/* Insert this event into the schedule */
+	s->next = current;
+	if (last) 
+		last->next = s;
+	else
+		con->schedq = s;
+	con->schedcnt++;
+}
+
+static inline int sched_settime(struct timeval *tv, int when)
+{
+	if (gettimeofday(tv, NULL) < 0) {
+			/* This shouldn't ever happen, but let's be sure */
+			ast_log(LOG_NOTICE, "gettimeofday() failed!\n");
+			return -1;
+	}
+	tv->tv_sec += when/1000;
+	tv->tv_usec += (when % 1000) * 1000;
+	if (tv->tv_usec > 1000000) {
+		tv->tv_sec++;
+		tv->tv_usec-= 1000000;
+	}
+	return 0;
+}
+
+int ast_sched_add(struct sched_context *con, int when, ast_sched_cb callback, void *data)
+{
+	/*
+	 * Schedule callback(data) to happen when ms into the future
+	 */
+	struct sched *tmp;
+	DEBUG(ast_log(LOG_DEBUG, "ast_sched_add()\n"));
+	if (!when) {
+		ast_log(LOG_NOTICE, "Scheduled event in 0 ms?");
+		return -1;
+	}
+	if ((tmp = sched_alloc(con))) {
+		tmp->id = con->eventcnt++;
+		tmp->callback = callback;
+		tmp->data = data;
+		tmp->resched = when;
+		if (sched_settime(&tmp->when, when)) {
+			sched_release(con, tmp);
+			return -1;
+		} else
+			schedule(con, tmp);
+	} else 
+		return -1;
+	return tmp->id;
+}
+
+int ast_sched_del(struct sched_context *con, int id)
+{
+	/*
+	 * Delete the schedule entry with number
+	 * "id".  It's nearly impossible that there
+	 * would be two or more in the list with that
+	 * id.
+	 */
+	struct sched *last=NULL, *s;
+	DEBUG(ast_log(LOG_DEBUG, "ast_sched_del()\n"));
+	s = con->schedq;
+	while(s) {
+		if (s->id == id) {
+			if (last)
+				last->next = s->next;
+			else
+				con->schedq = s->next;
+			con->schedcnt--;
+			return 0;
+		}
+		last = s;
+		s = s->next;
+	}
+	ast_log(LOG_NOTICE, "Attempted to delete non-existant schedule entry %d!\n", id);
+#ifdef FORCE_CRASH
+	crash();
+#endif
+	return -1;
+}
+
+void ast_sched_dump(struct sched_context *con)
+{
+	/*
+	 * Dump the contents of the scheduler to
+	 * stderr
+	 */
+	struct sched *q;
+	struct timeval tv;
+	time_t s, ms;
+	gettimeofday(&tv, NULL);
+	ast_log(LOG_DEBUG, "Cheops Schedule Dump (%d in Q, %d Total, %d Cache)\n", 
+							 con-> schedcnt, con->eventcnt - 1, con->schedccnt);
+	ast_log(LOG_DEBUG, "=================================================\n");
+	ast_log(LOG_DEBUG, "|ID    Callback    Data        Time  (sec:ms)   |\n");
+	ast_log(LOG_DEBUG, "+-----+-----------+-----------+-----------------+\n");
+	q = con->schedq;
+	while(q) {
+		s =  q->when.tv_sec - tv.tv_sec;
+		ms = q->when.tv_usec - tv.tv_usec;
+		if (ms < 0) {
+			ms += 1000000;
+			s--;
+		}
+		ast_log(LOG_DEBUG, "|%.4d | %p | %p | %.6ld : %.6ld |\n", 
+				q->id,
+				q->callback,
+				q->data,
+				s,
+				ms);
+		q=q->next;
+	}
+	ast_log(LOG_DEBUG, "=================================================\n");
+	
+}
+
+int ast_sched_runq(struct sched_context *con)
+{
+	/*
+	 * Launch all events which need to be run at this time.
+	 */
+	struct sched *current;
+	struct timeval tv;
+	int x=0;
+	DEBUG(ast_log(LOG_DEBUG, "ast_sched_runq()\n"));
+		
+	for(;;) {
+		if (!con->schedq)
+			break;
+		if (gettimeofday(&tv, NULL)) {
+			/* This should never happen */
+			ast_log(LOG_NOTICE, "gettimeofday() failed!\n");
+			return 0;
+		}
+		/* We only care about millisecond accuracy anyway, so this will
+		   help us get more than one event at one time if they are very
+		   close together. */
+		tv.tv_usec += 1000;
+		if (SOONER(con->schedq->when, tv)) {
+			current = con->schedq;
+			con->schedq = con->schedq->next;
+			con->schedcnt--;
+
+			/*
+			 * At this point, the schedule queue is still intact.  We
+			 * have removed the first event and the rest is still there,
+			 * so it's permissible for the callback to add new events, but
+			 * trying to delete itself won't work because it isn't in
+			 * the schedule queue.  If that's what it wants to do, it 
+			 * should return 0.
+			 */
+			if (current->callback(current->data)) {
+			 	/*
+				 * If they return non-zero, we should schedule them to be
+				 * run again.
+				 */
+				if (sched_settime(&current->when, current->resched)) {
+					sched_release(con, current);
+				} else
+					schedule(con, current);
+			} else {
+				/* No longer needed, so release it */
+			 	sched_release(con, current);
+			}
+			x++;
+		} else
+			break;
+	}
+	return x;
+}