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+/*
+ * Copyright (c) 1997-2014 Erez Zadok
+ * Copyright (c) 1990 Jan-Simon Pendry
+ * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Jan-Simon Pendry at Imperial College, London.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *
+ * File: am-utils/libamu/ualarm.c
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif /* HAVE_CONFIG_H */
+#include <am_defs.h>
+#include <amu.h>
+
+#define USPS 1000000 /* # of microseconds in a second */
+
+
+/*
+ * Generate a SIGALRM signal in ``usecs'' microseconds.
+ * If ``reload'' is non-zero, keep generating SIGALRM
+ * every ``reload'' microseconds after the first signal.
+ */
+u_int
+ualarm(u_int usecs, u_int interval)
+{
+ struct itimerval new, old;
+
+ new.it_interval.tv_usec = interval % USPS;
+ new.it_interval.tv_sec = interval / USPS;
+ new.it_value.tv_usec = usecs % USPS;
+ new.it_value.tv_sec = usecs / USPS;
+
+ if (setitimer(ITIMER_REAL, &new, &old) == 0)
+ return (old.it_value.tv_sec * USPS + old.it_value.tv_usec);
+
+ return -1;
+}