/* Copyright (C) 2000, 2001 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Kaz Kylheku <kaz@ashi.footprints.net>. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <errno.h> #include <pthread.h> #include <time.h> #include "posix-timer.h" /* Set timer TIMERID to VALUE, returning old value in OVLAUE. */ int timer_settime (timerid, flags, value, ovalue) timer_t timerid; int flags; const struct itimerspec *value; struct itimerspec *ovalue; { struct timer_node *timer; struct thread_node *thread = NULL; struct timespec now; int have_now = 0, need_wakeup = 0; int retval = -1; timer = timer_id2ptr (timerid); if (timer == NULL) { __set_errno (EINVAL); goto bail; } if (value->it_interval.tv_nsec < 0 || value->it_interval.tv_nsec >= 1000000000 || value->it_value.tv_nsec < 0 || value->it_value.tv_nsec >= 1000000000) { __set_errno (EINVAL); goto bail; } /* Will need to know current time since this is a relative timer; might as well make the system call outside of the lock now! */ if ((flags & TIMER_ABSTIME) == 0) { clock_gettime (timer->clock, &now); have_now = 1; } pthread_mutex_lock (&__timer_mutex); timer_addref (timer); /* One final check of timer validity; this one is possible only until we have the mutex, because it accesses the inuse flag. */ if (! timer_valid(timer)) { __set_errno (EINVAL); goto unlock_bail; } if (ovalue != NULL) { ovalue->it_interval = timer->value.it_interval; if (timer->armed) { if (! have_now) { pthread_mutex_unlock (&__timer_mutex); clock_gettime (timer->clock, &now); have_now = 1; pthread_mutex_lock (&__timer_mutex); timer_addref (timer); } timespec_sub (&ovalue->it_value, &timer->expirytime, &now); } else { ovalue->it_value.tv_sec = 0; ovalue->it_value.tv_nsec = 0; } } timer->value = *value; list_unlink_ip (&timer->links); timer->armed = 0; thread = timer->thread; /* A value of { 0, 0 } causes the timer to be stopped. */ if (value->it_value.tv_sec != 0 || __builtin_expect (value->it_value.tv_nsec != 0, 1)) { if ((flags & TIMER_ABSTIME) != 0) /* The user specified the expiration time. */ timer->expirytime = value->it_value; else timespec_add (&timer->expirytime, &now, &value->it_value); /* Only need to wake up the thread if timer is inserted at the head of the queue. */ if (thread != NULL) need_wakeup = __timer_thread_queue_timer (thread, timer); timer->armed = 1; } retval = 0; unlock_bail: timer_delref (timer); pthread_mutex_unlock (&__timer_mutex); bail: if (thread != NULL && need_wakeup) __timer_thread_wakeup (thread); return retval; }