diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/features.h | 1 | ||||
| -rw-r--r-- | include/semaphore.h | 80 |
2 files changed, 81 insertions, 0 deletions
diff --git a/include/features.h b/include/features.h index 033cf98d6..580ed3ee6 100644 --- a/include/features.h +++ b/include/features.h @@ -378,6 +378,7 @@ /* This comes between the return type and function name in * a function definition to make that definition weak. */ # define weak_function __attribute__ ((weak)) +# define weak_const_function __attribute__ ((weak, __const__)) /* Tacking on "\n\t#" to the section name makes gcc put it's bogus * section attributes on what looks like a comment to the assembler. */ # define link_warning(symbol, msg) \ diff --git a/include/semaphore.h b/include/semaphore.h new file mode 100644 index 000000000..84742233b --- /dev/null +++ b/include/semaphore.h @@ -0,0 +1,80 @@ +/* Linuxthreads - a simple clone()-based implementation of Posix */ +/* threads for Linux. */ +/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ +/* */ +/* This program is free software; you can redistribute it and/or */ +/* modify it under the terms of the GNU Library General Public License */ +/* as published by the Free Software Foundation; either version 2 */ +/* of the License, or (at your option) any later version. */ +/* */ +/* This program 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 Library General Public License for more details. */ + +#ifndef _SEMAPHORE_H +#define _SEMAPHORE_H 1 + +#include <features.h> +#include <sys/types.h> + +#ifndef _PTHREAD_DESCR_DEFINED +/* Thread descriptors. Needed for `sem_t' definition. */ +typedef struct _pthread_descr_struct *_pthread_descr; +# define _PTHREAD_DESCR_DEFINED +#endif + +/* System specific semaphore definition. */ +typedef struct +{ + struct + { + long int status; + int spinlock; + } __sem_lock; + int __sem_value; + _pthread_descr __sem_waiting; +} sem_t; + + + +/* Value returned if `sem_open' failed. */ +#define SEM_FAILED ((sem_t *) 0) + +/* Maximum value the semaphore can have. */ +#define SEM_VALUE_MAX ((int) ((~0u) >> 1)) + + +__BEGIN_DECLS + +/* Initialize semaphore object SEM to VALUE. If PSHARED then share it + with other processes. */ +extern int sem_init __P ((sem_t *__sem, int __pshared, unsigned int __value)); + +/* Free resources associated with semaphore object SEM. */ +extern int sem_destroy __P ((sem_t *__sem)); + +/* Open a named semaphore NAME with open flaot OFLAG. */ +extern sem_t *sem_open __P ((__const char *__name, int __oflag, ...)); + +/* Close descriptor for named semaphore SEM. */ +extern int sem_close __P ((sem_t *__sem)); + +/* Remove named semaphore NAME. */ +extern int sem_unlink __P ((__const char *__name)); + +/* Wait for SEM being posted. */ +extern int sem_wait __P ((sem_t *__sem)); + +/* Test whether SEM is posted. */ +extern int sem_trywait __P ((sem_t *__sem)); + +/* Post SEM. */ +extern int sem_post __P ((sem_t *__sem)); + +/* Get current value of SEM and store it in *SVAL. */ +extern int sem_getvalue __P ((sem_t *__sem, int *__sval)); + +__END_DECLS + +#endif /* semaphore.h */ |