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Diffstat (limited to 'libamu/ualarm.c')
-rw-r--r-- | libamu/ualarm.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/libamu/ualarm.c b/libamu/ualarm.c new file mode 100644 index 000000000000..86280d92b75a --- /dev/null +++ b/libamu/ualarm.c @@ -0,0 +1,68 @@ +/* + * 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; +} |