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/* Copyright (C) 2000 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 <signal.h>
#include <pthread.h>
#include <time.h>
#include <unistd.h>
#include "posix-timer.h"
/* Create new per-process timer using CLOCK. */
int
timer_create (clock_id, evp, timerid)
clockid_t clock_id;
struct sigevent *evp;
timer_t *timerid;
{
int retval = -1;
struct timer_node *newtimer = NULL;
struct thread_node *thread = NULL;
if (clock_id != CLOCK_REALTIME
#ifdef _POSIX_CPUTIME
&& clock_id != CLOCK_PROCESS_CPUTIME_ID
#endif
#ifdef _POSIX_THREAD_CPUTIME
&& clock_id != CLOCK_THREAD_CPUTIME_ID
#endif
)
{
__set_errno (EINVAL);
return -1;
}
pthread_once (&__timer_init_once_control, __timer_init_once);
if (__timer_init_failed)
{
__set_errno (ENOMEM);
return -1;
}
pthread_mutex_lock (&__timer_mutex);
newtimer = __timer_alloc ();
if (__builtin_expect (newtimer == NULL, 0))
{
__set_errno (EAGAIN);
goto unlock_bail;
}
if (evp != NULL)
newtimer->event = *evp;
else
{
newtimer->event.sigev_notify = SIGEV_SIGNAL;
newtimer->event.sigev_signo = SIGALRM;
newtimer->event.sigev_value.sival_int = timer_ptr2id (newtimer);
newtimer->event.sigev_notify_function = 0;
}
newtimer->event.sigev_notify_attributes = &newtimer->attr;
newtimer->creator_pid = getpid ();
switch (__builtin_expect (newtimer->event.sigev_notify, SIGEV_SIGNAL))
{
case SIGEV_NONE:
/* This is a strange choice! */
break;
case SIGEV_SIGNAL:
/* We have a global thread for delivering timed signals.
If it is not running, try to start it up. */
switch (clock_id)
{
case CLOCK_REALTIME:
default:
thread = &__timer_signal_thread_rclk;
break;
#ifdef _POSIX_CPUTIME
case CLOCK_PROCESS_CPUTIME_ID:
thread = &__timer_signal_thread_pclk;
break;
#endif
#ifdef _POSIX_THREAD_CPUTIME
case CLOCK_THREAD_CPUTIME_ID:
thread = &__timer_signal_thread_tclk;
break;
#endif
}
if (! thread->exists)
{
if (__builtin_expect (__timer_thread_start (thread),
1) < 0)
{
__set_errno (EAGAIN);
goto unlock_bail;
}
}
break;
case SIGEV_THREAD:
/* Copy over thread attributes or set up default ones. */
if (evp->sigev_notify_attributes)
newtimer->attr = *(pthread_attr_t *) evp->sigev_notify_attributes;
else
pthread_attr_init (&newtimer->attr);
/* Ensure thread attributes call for deatched thread. */
pthread_attr_setdetachstate (&newtimer->attr, PTHREAD_CREATE_DETACHED);
/* Try to find existing thread having the right attributes. */
thread = __timer_thread_find_matching (&newtimer->attr, clock_id);
/* If no existing thread has these attributes, try to allocate one. */
if (thread == NULL)
thread = __timer_thread_alloc (&newtimer->attr, clock_id);
/* Out of luck; no threads are available. */
if (__builtin_expect (thread == NULL, 0))
{
__set_errno (EAGAIN);
goto unlock_bail;
}
/* If the thread is not running already, try to start it. */
if (! thread->exists
&& __builtin_expect (! __timer_thread_start (thread), 0))
{
__set_errno (EAGAIN);
goto unlock_bail;
}
break;
default:
__set_errno (EINVAL);
goto unlock_bail;
}
newtimer->clock = clock_id;
newtimer->abstime = 0;
newtimer->armed = 0;
newtimer->thread = thread;
*timerid = timer_ptr2id (newtimer);
retval = 0;
if (__builtin_expect (retval, 0) == -1)
{
unlock_bail:
if (thread != NULL)
__timer_thread_dealloc (thread);
if (newtimer != NULL)
__timer_dealloc (newtimer);
}
pthread_mutex_unlock (&__timer_mutex);
return retval;
}
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