diff options
Diffstat (limited to 'rt/timer_create.c')
| -rw-r--r-- | rt/timer_create.c | 156 |
1 files changed, 147 insertions, 9 deletions
diff --git a/rt/timer_create.c b/rt/timer_create.c index 79d4d18317..2808f5b32b 100644 --- a/rt/timer_create.c +++ b/rt/timer_create.c @@ -1,10 +1,11 @@ -/* Copyright (C) 1999-2021 Free Software Foundation, Inc. +/* Copyright (C) 2000-2021 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. + 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 @@ -12,17 +13,154 @@ 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; if not, see - <https://www.gnu.org/licenses/>. */ + License along with the GNU C Library; see the file COPYING.LIB. If + not, see <https://www.gnu.org/licenses/>. */ #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 (clockid_t clock_id, struct sigevent *evp, timer_t *timerid) { - __set_errno (ENOSYS); - return -1; + int retval = -1; + struct timer_node *newtimer = NULL; + struct thread_node *thread = NULL; + + if (0 +#if defined _POSIX_CPUTIME && _POSIX_CPUTIME >= 0 + || clock_id == CLOCK_PROCESS_CPUTIME_ID +#endif +#if defined _POSIX_THREAD_CPUTIME && _POSIX_THREAD_CPUTIME >= 0 + || clock_id == CLOCK_THREAD_CPUTIME_ID +#endif + ) + { + /* We don't allow timers for CPU clocks. At least not in the + moment. */ + __set_errno (ENOTSUP); + return -1; + } + + if (clock_id != CLOCK_REALTIME) + { + __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 (__glibc_unlikely (newtimer == NULL)) + { + __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_ptr = 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: + case SIGEV_SIGNAL: + /* We have a global thread for delivering timed signals. + If it is not running, try to start it up. */ + thread = &__timer_signal_thread_rclk; + 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 (__glibc_unlikely (thread == NULL)) + { + __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_delref (newtimer); + __timer_dealloc (newtimer); + } + } + + pthread_mutex_unlock (&__timer_mutex); + + return retval; } -stub_warning (timer_create) |