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-rw-r--r--package/openntpd/extra/openbsd-compat/port-linux.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/package/openntpd/extra/openbsd-compat/port-linux.c b/package/openntpd/extra/openbsd-compat/port-linux.c
new file mode 100644
index 000000000..f210d4a6d
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+++ b/package/openntpd/extra/openbsd-compat/port-linux.c
@@ -0,0 +1,107 @@
+/* $Id: port-linux.c 1793 2007-01-28 20:55:08Z tg $ */
+
+/* part of the adjtime-linux patch */
+
+/*
+ * Copyright (c) 2004 Darren Tucker <dtucker at zip com au>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "includes.h"
+
+#ifdef USE_ADJTIMEX
+#include <sys/timex.h>
+#include <errno.h>
+#ifdef adjtime
+# undef adjtime
+#endif
+
+#include "ntpd.h"
+
+/* scale factor used by adjtimex freq param. 1 ppm = 65536 */
+#define ADJTIMEX_FREQ_SCALE 65536
+
+/* maximum change to skew per adjustment, in PPM */
+#define MAX_SKEW_DELTA 5.0
+
+int
+_compat_adjtime(const struct timeval *delta, struct timeval *olddelta)
+{
+ static struct timeval tlast = {0,0};
+ static double tskew = 0;
+ static int synced = -1;
+ struct timeval tnow, tdelta;
+ double skew = 0, newskew, deltaskew, adjust, interval = 0;
+ struct timex tmx;
+ int result, saved_errno;
+
+ gettimeofday(&tnow, NULL);
+ adjust = (double)delta->tv_sec;
+ adjust += (double)delta->tv_usec / 1000000;
+
+ /* Even if the caller doesn't care about the olddelta, we do */
+ if (olddelta == NULL)
+ olddelta = &tdelta;
+
+ result = adjtime(delta, olddelta);
+ saved_errno = errno;
+
+ if (olddelta->tv_sec == 0 && olddelta->tv_usec == 0 &&
+ synced != INT_MAX)
+ synced++;
+ else
+ synced = 0;
+
+ /*
+ * do skew calculations if we have synced
+ */
+ if (synced == 0 ) {
+ tmx.modes = 0;
+ if (adjtimex(&tmx) == -1)
+ log_warn("adjtimex get failed");
+ else
+ tskew = (double)tmx.freq / ADJTIMEX_FREQ_SCALE;
+ } else if (synced >= 1) {
+ interval = (double)(tnow.tv_sec - tlast.tv_sec);
+ interval += (double)(tnow.tv_usec - tlast.tv_usec) / 1000000;
+
+ skew = (adjust * 1000000) / interval;
+ newskew = ((tskew * synced) + skew) / synced;
+ deltaskew = newskew - tskew;
+
+ if (deltaskew > MAX_SKEW_DELTA) {
+ log_info("skew change %0.3lf exceeds limit", deltaskew);
+ tskew += MAX_SKEW_DELTA;
+ } else if (deltaskew < -MAX_SKEW_DELTA) {
+ log_info("skew change %0.3lf exceeds limit", deltaskew);
+ tskew -= MAX_SKEW_DELTA;
+ } else {
+ tskew = newskew;
+ }
+
+ /* Adjust the kernel skew. */
+ tmx.freq = (long)(tskew * ADJTIMEX_FREQ_SCALE);
+ tmx.modes = ADJ_FREQUENCY;
+ if (adjtimex(&tmx) == -1)
+ log_warn("adjtimex set freq failed");
+ }
+
+ log_debug("interval %0.3lf skew %0.3lf total skew %0.3lf", interval,
+ skew, tskew);
+
+ tlast = tnow;
+ errno = saved_errno;
+ return result;
+}
+#endif