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Diffstat (limited to 'sysdeps/pthread/threads.h')
-rw-r--r-- | sysdeps/pthread/threads.h | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/sysdeps/pthread/threads.h b/sysdeps/pthread/threads.h new file mode 100644 index 0000000000..0ac489b4a1 --- /dev/null +++ b/sysdeps/pthread/threads.h @@ -0,0 +1,204 @@ +/* ISO C11 Standard: 7.26 - Thread support library <threads.h>. + Copyright (C) 2018-2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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; if not, see + <https://www.gnu.org/licenses/>. */ + +#ifndef _THREADS_H +#define _THREADS_H 1 + +#include <features.h> +#include <time.h> + +__BEGIN_DECLS + +#include <bits/thread-shared-types.h> +#include <bits/types/struct_timespec.h> + +#ifndef __cplusplus +# define thread_local _Thread_local +#endif + +#define TSS_DTOR_ITERATIONS 4 +typedef __tss_t tss_t; +typedef void (*tss_dtor_t) (void*); + +typedef __thrd_t thrd_t; +typedef int (*thrd_start_t) (void*); + +/* Exit and error codes. */ +enum +{ + thrd_success = 0, + thrd_busy = 1, + thrd_error = 2, + thrd_nomem = 3, + thrd_timedout = 4 +}; + +/* Mutex types. */ +enum +{ + mtx_plain = 0, + mtx_recursive = 1, + mtx_timed = 2 +}; + +typedef __once_flag once_flag; +#define ONCE_FLAG_INIT __ONCE_FLAG_INIT + +typedef union +{ + char __size[__SIZEOF_PTHREAD_MUTEX_T]; + long int __align __LOCK_ALIGNMENT; +} mtx_t; + +typedef union +{ + char __size[__SIZEOF_PTHREAD_COND_T]; + __extension__ long long int __align __LOCK_ALIGNMENT; +} cnd_t; + +/* Threads functions. */ + +/* Create a new thread executing the function __FUNC. Arguments for __FUNC + are passed through __ARG. If succesful, __THR is set to new thread + identifier. */ +extern int thrd_create (thrd_t *__thr, thrd_start_t __func, void *__arg); + +/* Check if __LHS and __RHS point to the same thread. */ +extern int thrd_equal (thrd_t __lhs, thrd_t __rhs); + +/* Return current thread identifier. */ +extern thrd_t thrd_current (void); + +/* Block current thread execution for at least the time pointed by + __TIME_POINT. The current thread may resume if receives a signal. In + that case, if __REMAINING is not NULL, the remaining time is stored in + the object pointed by it. */ +extern int thrd_sleep (const struct timespec *__time_point, + struct timespec *__remaining); + +/* Terminate current thread execution, cleaning up any thread local + storage and freeing resources. Returns the value specified in __RES. */ +extern void thrd_exit (int __res) __attribute__ ((__noreturn__)); + +/* Detach the thread identified by __THR from the current environment + (it does not allow join or wait for it). */ +extern int thrd_detach (thrd_t __thr); + +/* Block current thread until execution of __THR is complete. In case that + __RES is not NULL, will store the return value of __THR when exiting. */ +extern int thrd_join (thrd_t __thr, int *__res); + +/* Stop current thread execution and call the scheduler to decide which + thread should execute next. The current thread may be selected by the + scheduler to keep running. */ +extern void thrd_yield (void); + +#ifdef __USE_EXTERN_INLINES +/* Optimizations. */ +__extern_inline int +thrd_equal (thrd_t __thread1, thrd_t __thread2) +{ + return __thread1 == __thread2; +} +#endif + + +/* Mutex functions. */ + +/* Creates a new mutex object with type __TYPE. If successful the new + object is pointed by __MUTEX. */ +extern int mtx_init (mtx_t *__mutex, int __type); + +/* Block the current thread until the mutex pointed to by __MUTEX is + unlocked. In that case current thread will not be blocked. */ +extern int mtx_lock (mtx_t *__mutex); + +/* Block the current thread until the mutex pointed by __MUTEX is unlocked + or time pointed by __TIME_POINT is reached. In case the mutex is unlock, + the current thread will not be blocked. */ +extern int mtx_timedlock (mtx_t *__restrict __mutex, + const struct timespec *__restrict __time_point); + +/* Try to lock the mutex pointed by __MUTEX without blocking. If the mutex + is free the current threads takes control of it, otherwise it returns + immediately. */ +extern int mtx_trylock (mtx_t *__mutex); + +/* Unlock the mutex pointed by __MUTEX. It may potentially awake other + threads waiting on this mutex. */ +extern int mtx_unlock (mtx_t *__mutex); + +/* Destroy the mutex object pointed by __MUTEX. */ +extern void mtx_destroy (mtx_t *__mutex); + + +/* Call function __FUNC exactly once, even if invoked from several threads. + All calls must be made with the same __FLAGS object. */ +extern void call_once (once_flag *__flag, void (*__func)(void)); + + +/* Condition variable functions. */ + +/* Initialize new condition variable pointed by __COND. */ +extern int cnd_init (cnd_t *__cond); + +/* Unblock one thread that currently waits on condition variable pointed + by __COND. */ +extern int cnd_signal (cnd_t *__cond); + +/* Unblock all threads currently waiting on condition variable pointed by + __COND. */ +extern int cnd_broadcast (cnd_t *__cond); + +/* Block current thread on the condition variable pointed by __COND. */ +extern int cnd_wait (cnd_t *__cond, mtx_t *__mutex); + +/* Block current thread on the condition variable until condition variable + pointed by __COND is signaled or time pointed by __TIME_POINT is + reached. */ +extern int cnd_timedwait (cnd_t *__restrict __cond, + mtx_t *__restrict __mutex, + const struct timespec *__restrict __time_point); + +/* Destroy condition variable pointed by __cond and free all of its + resources. */ +extern void cnd_destroy (cnd_t *__COND); + + +/* Thread specific storage functions. */ + +/* Create new thread-specific storage key and stores it in the object pointed + by __TSS_ID. If __DESTRUCTOR is not NULL, the function will be called when + the thread terminates. */ +extern int tss_create (tss_t *__tss_id, tss_dtor_t __destructor); + +/* Return the value held in thread-specific storage for the current thread + identified by __TSS_ID. */ +extern void *tss_get (tss_t __tss_id); + +/* Sets the value of the thread-specific storage identified by __TSS_ID for + the current thread to __VAL. */ +extern int tss_set (tss_t __tss_id, void *__val); + +/* Destroys the thread-specific storage identified by __TSS_ID. The + destructor is not called until thrd_exit is called. */ +extern void tss_delete (tss_t __tss_id); + +__END_DECLS + +#endif /* _THREADS_H */ |