Add semaphores API.
This commit is contained in:
parent
0329192ba8
commit
392472af5c
10 changed files with 389 additions and 2 deletions
|
@ -96,8 +96,7 @@ __BEGIN_DECLS
|
|||
TODO: Uncomment when regular expressions are implemented. */
|
||||
/* #define _POSIX_SAVED_IDS 1
|
||||
TODO: Uncomment when saved ids are implemented. I forgot if they already are. */
|
||||
/* #define _POSIX_SEMAPHORES 200809L
|
||||
TODO: Uncomment when named semaphores are implemented. */
|
||||
#define _POSIX_SEMAPHORES 200809L
|
||||
/*TODO: _POSIX_SHARED_MEMORY_OBJECTS - Research what this is. */
|
||||
#define _POSIX_SHELL 1
|
||||
/*TODO: _POSIX_SPAWN - Research what this is. */
|
||||
|
|
|
@ -56,6 +56,13 @@ pthread_rwlock_wrlock.o \
|
|||
pthread_self.o \
|
||||
pthread_setspecific.o \
|
||||
pthread_sigmask.o \
|
||||
sem_destroy.o \
|
||||
sem_getvalue.o \
|
||||
sem_init.o \
|
||||
sem_post.o \
|
||||
sem_timedwait.o \
|
||||
sem_trywait.o \
|
||||
sem_wait.o \
|
||||
|
||||
BINS:=libpthread.a
|
||||
|
||||
|
|
58
libpthread/include/semaphore.h
Normal file
58
libpthread/include/semaphore.h
Normal file
|
@ -0,0 +1,58 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
semaphore.h
|
||||
Semaphore API.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#ifndef INCLUDE_SEMAPHORE_H
|
||||
#define INCLUDE_SEMAPHORE_H
|
||||
|
||||
#include <features.h>
|
||||
|
||||
#include <sortix/timespec.h>
|
||||
|
||||
__BEGIN_DECLS
|
||||
|
||||
typedef struct
|
||||
{
|
||||
#if defined(__is_sortix_libpthread)
|
||||
int value;
|
||||
#else
|
||||
int __value;
|
||||
#endif
|
||||
} sem_t;
|
||||
|
||||
#define SEM_FAILED ((sem_t*) 0)
|
||||
|
||||
/*int sem_close(sem_t*);*/
|
||||
int sem_destroy(sem_t*);
|
||||
int sem_getvalue(sem_t* __restrict, int* __restrict);
|
||||
int sem_init(sem_t*, int, unsigned int);
|
||||
/*sem_t* sem_open(const char*, int, ...);*/
|
||||
int sem_post(sem_t*);
|
||||
int sem_timedwait(sem_t* __restrict, const struct timespec* __restrict);
|
||||
int sem_trywait(sem_t*);
|
||||
/*int sem_unlink(const char*);*/
|
||||
int sem_wait(sem_t*);
|
||||
|
||||
__END_DECLS
|
||||
|
||||
#endif
|
31
libpthread/sem_destroy.c++
Normal file
31
libpthread/sem_destroy.c++
Normal file
|
@ -0,0 +1,31 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_destroy.c++
|
||||
Destroy a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <semaphore.h>
|
||||
|
||||
extern "C" int sem_destroy(sem_t* sem)
|
||||
{
|
||||
(void) sem;
|
||||
return 0;
|
||||
}
|
31
libpthread/sem_getvalue.c++
Normal file
31
libpthread/sem_getvalue.c++
Normal file
|
@ -0,0 +1,31 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_getvalue.c++
|
||||
Get the value of a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <semaphore.h>
|
||||
|
||||
extern "C" int sem_getvalue(sem_t* restrict sem, int* restrict value_ptr)
|
||||
{
|
||||
*value_ptr = __atomic_load_n(&sem->value, __ATOMIC_SEQ_CST);
|
||||
return 0;
|
||||
}
|
40
libpthread/sem_init.c++
Normal file
40
libpthread/sem_init.c++
Normal file
|
@ -0,0 +1,40 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_init.c++
|
||||
Initialize a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <errno.h>
|
||||
#include <limits.h>
|
||||
#include <semaphore.h>
|
||||
|
||||
extern "C" int sem_init(sem_t* sem, int pshared, unsigned int value)
|
||||
{
|
||||
if ( pshared )
|
||||
return errno = ENOSYS, -1;
|
||||
|
||||
if ( (unsigned int) INT_MAX < value )
|
||||
return errno = EINVAL, -1;
|
||||
|
||||
sem->value = (int) value;
|
||||
|
||||
return 0;
|
||||
}
|
45
libpthread/sem_post.c++
Normal file
45
libpthread/sem_post.c++
Normal file
|
@ -0,0 +1,45 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_post.c++
|
||||
Unlock a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <errno.h>
|
||||
#include <limits.h>
|
||||
#include <semaphore.h>
|
||||
|
||||
extern "C" int sem_post(sem_t* sem)
|
||||
{
|
||||
while ( true )
|
||||
{
|
||||
int old_value = __atomic_load_n(&sem->value, __ATOMIC_SEQ_CST);
|
||||
if ( old_value == INT_MAX )
|
||||
return errno = EOVERFLOW;
|
||||
|
||||
int new_value = old_value + 1;
|
||||
if ( !__atomic_compare_exchange_n(&sem->value, &old_value, new_value,
|
||||
false,
|
||||
__ATOMIC_SEQ_CST, __ATOMIC_RELAXED) )
|
||||
continue;
|
||||
|
||||
return 0;
|
||||
}
|
||||
}
|
76
libpthread/sem_timedwait.c++
Normal file
76
libpthread/sem_timedwait.c++
Normal file
|
@ -0,0 +1,76 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_timedwait.c++
|
||||
Lock a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <errno.h>
|
||||
#include <sched.h>
|
||||
#include <semaphore.h>
|
||||
#include <signal.h>
|
||||
#include <stddef.h>
|
||||
#include <time.h>
|
||||
#include <timespec.h>
|
||||
|
||||
extern "C"
|
||||
int sem_timedwait(sem_t* restrict sem, const struct timespec* restrict abstime)
|
||||
{
|
||||
if ( sem_trywait(sem) == 0 )
|
||||
return 0;
|
||||
if ( errno != EAGAIN )
|
||||
return -1;
|
||||
|
||||
sigset_t old_set_mask;
|
||||
sigset_t old_set_allowed;
|
||||
sigset_t all_signals;
|
||||
sigfillset(&all_signals);
|
||||
sigprocmask(SIG_SETMASK, &all_signals, &old_set_mask);
|
||||
signotset(&old_set_allowed, &old_set_mask);
|
||||
|
||||
while ( sem_trywait(sem) != 0 )
|
||||
{
|
||||
// TODO: Using CLOCK_REALTIME for this is bad as it is not monotonic. We
|
||||
// need to enchance the semaphore API so a better clock can be
|
||||
// used instead.
|
||||
if ( errno == EAGAIN )
|
||||
{
|
||||
struct timespec now;
|
||||
clock_gettime(CLOCK_REALTIME, &now);
|
||||
if ( timespec_le(*abstime, now) )
|
||||
errno = ETIMEDOUT;
|
||||
}
|
||||
|
||||
if ( errno == EAGAIN && sigpending(&old_set_allowed) )
|
||||
errno = EINTR;
|
||||
|
||||
if ( errno != EAGAIN )
|
||||
{
|
||||
sigprocmask(SIG_SETMASK, &old_set_mask, NULL);
|
||||
return -1;
|
||||
}
|
||||
|
||||
sched_yield();
|
||||
}
|
||||
|
||||
sigprocmask(SIG_SETMASK, &old_set_mask, NULL);
|
||||
|
||||
return 0;
|
||||
}
|
38
libpthread/sem_trywait.c++
Normal file
38
libpthread/sem_trywait.c++
Normal file
|
@ -0,0 +1,38 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_trywait.c++
|
||||
Lock a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <errno.h>
|
||||
#include <semaphore.h>
|
||||
|
||||
extern "C" int sem_trywait(sem_t* sem)
|
||||
{
|
||||
int old_value = __atomic_load_n(&sem->value, __ATOMIC_SEQ_CST);
|
||||
if ( old_value <= 0 )
|
||||
return errno = EAGAIN, -1;
|
||||
int new_value = old_value - 1;
|
||||
if ( !__atomic_compare_exchange_n(&sem->value, &old_value, new_value, false,
|
||||
__ATOMIC_SEQ_CST, __ATOMIC_RELAXED) )
|
||||
return errno = EAGAIN, -1;
|
||||
return 0;
|
||||
}
|
62
libpthread/sem_wait.c++
Normal file
62
libpthread/sem_wait.c++
Normal file
|
@ -0,0 +1,62 @@
|
|||
/*******************************************************************************
|
||||
|
||||
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||
|
||||
This file is part of Sortix libpthread.
|
||||
|
||||
Sortix libpthread 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 3 of the License, or (at your
|
||||
option) any later version.
|
||||
|
||||
Sortix libpthread 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 Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
sem_wait.c++
|
||||
Lock a semaphore.
|
||||
|
||||
*******************************************************************************/
|
||||
|
||||
#include <errno.h>
|
||||
#include <sched.h>
|
||||
#include <semaphore.h>
|
||||
#include <signal.h>
|
||||
#include <stddef.h>
|
||||
|
||||
extern "C" int sem_wait(sem_t* sem)
|
||||
{
|
||||
if ( sem_trywait(sem) == 0 )
|
||||
return 0;
|
||||
if ( errno != EAGAIN )
|
||||
return -1;
|
||||
|
||||
sigset_t old_set_mask;
|
||||
sigset_t old_set_allowed;
|
||||
sigset_t all_signals;
|
||||
sigfillset(&all_signals);
|
||||
sigprocmask(SIG_SETMASK, &all_signals, &old_set_mask);
|
||||
signotset(&old_set_allowed, &old_set_mask);
|
||||
|
||||
while ( sem_trywait(sem) != 0 )
|
||||
{
|
||||
if ( errno == EAGAIN && sigpending(&old_set_allowed) )
|
||||
errno = EINTR;
|
||||
|
||||
if ( errno != EAGAIN )
|
||||
{
|
||||
sigprocmask(SIG_SETMASK, &old_set_mask, NULL);
|
||||
return -1;
|
||||
}
|
||||
|
||||
sched_yield();
|
||||
}
|
||||
|
||||
sigprocmask(SIG_SETMASK, &old_set_mask, NULL);
|
||||
|
||||
return 0;
|
||||
}
|
Loading…
Reference in a new issue