1 /* Copyright (C) 2003-2024 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If
16 not, see <https://www.gnu.org/licenses/>. */
21 #include <sys/types.h>
24 /* Nonzero if the system calls are not available. */
25 extern int __no_posix_timers attribute_hidden
;
27 /* Callback to start helper thread. */
28 extern void __timer_start_helper_thread (void) attribute_hidden
;
30 /* Control variable for helper thread creation. */
31 extern pthread_once_t __timer_helper_once attribute_hidden
;
33 /* Called from fork so that the new subprocess re-creates the
34 notification thread if necessary. */
35 void __timer_fork_subprocess (void) attribute_hidden
;
37 /* TID of the helper thread. */
38 extern pid_t __timer_helper_tid attribute_hidden
;
40 /* List of active SIGEV_THREAD timers. */
41 extern struct timer
*__timer_active_sigev_thread attribute_hidden
;
43 /* Lock for __timer_active_sigev_thread. */
44 extern pthread_mutex_t __timer_active_sigev_thread_lock attribute_hidden
;
46 extern __typeof (timer_create
) __timer_create
;
47 libc_hidden_proto (__timer_create
)
48 extern __typeof (timer_delete
) __timer_delete
;
49 libc_hidden_proto (__timer_delete
)
50 extern __typeof (timer_getoverrun
) __timer_getoverrun
;
51 libc_hidden_proto (__timer_getoverrun
)
53 /* Type of timers in the kernel. */
54 typedef int kernel_timer_t
;
56 /* Internal representation of SIGEV_THREAD timer. */
59 kernel_timer_t ktimerid
;
61 void (*thrfunc
) (sigval_t
);
65 /* Next element in list of active SIGEV_THREAD timers. */
70 /* For !SIGEV_THREAD, the resulting 'timer_t' is the returned kernel timer
71 identifier (kernel_timer_t), while for SIGEV_THREAD it uses the fact malloc
72 returns at least _Alignof (max_align_t) pointers plus that valid
73 kernel_timer_t are always positive to set the MSB bit of the returned
74 'timer_t' to indicate the timer handles a SIGEV_THREAD. */
77 kernel_timer_to_timerid (kernel_timer_t ktimerid
)
79 return (timer_t
) ((intptr_t) ktimerid
);
83 timer_to_timerid (struct timer
*ptr
)
85 return (timer_t
) (INTPTR_MIN
| (uintptr_t) ptr
>> 1);
89 timer_is_sigev_thread (timer_t timerid
)
91 return (intptr_t) timerid
< 0;
94 static inline struct timer
*
95 timerid_to_timer (timer_t timerid
)
97 return (struct timer
*)((uintptr_t) timerid
<< 1);
100 static inline kernel_timer_t
101 timerid_to_kernel_timer (timer_t timerid
)
103 if (timer_is_sigev_thread (timerid
))
104 return timerid_to_timer (timerid
)->ktimerid
;
106 return (kernel_timer_t
) ((uintptr_t) timerid
);
109 /* New targets use int instead of timer_t. The difference only
110 matters on 64-bit targets. */
111 #include <timer_t_was_int_compat.h>
113 #if TIMER_T_WAS_INT_COMPAT
114 # define OLD_TIMER_MAX 256
115 extern timer_t __timer_compat_list
[OLD_TIMER_MAX
];