compiler/pthread/semaphore.h

   1 /*
   2   Copyright (C) 2015 Szilard Biro
   3
   4   This software is provided 'as-is', without any express or implied
   5   warranty.  In no event will the authors be held liable for any damages
   6   arising from the use of this software.
   7
   8   Permission is granted to anyone to use this software for any purpose,
   9   including commercial applications, and to alter it and redistribute it
  10   freely, subject to the following restrictions:
  11
  12   1. The origin of this software must not be misrepresented; you must not
  13      claim that you wrote the original software. If you use this software
  14      in a product, an acknowledgment in the product documentation would be
  15      appreciated but is not required.
  16   2. Altered source versions must be plainly marked as such, and must not be
  17      misrepresented as being the original software.
  18   3. This notice may not be removed or altered from any source distribution.
  19 */
  20
  21 #ifndef SEMAPHORE_H
  22 #define SEMAPHORE_H
  23
  24 #include <pthread.h>
  25 #include <time.h>
  26 #include <limits.h>
  27
  28 #undef _POSIX_SEMAPHORES
  29 #define _POSIX_SEMAPHORES
  30
  31 #undef SEM_VALUE_MAX
  32 #define SEM_VALUE_MAX INT_MAX
  33
  34 #undef SEM_NSEMS_MAX
  35 #define SEM_NSEMS_MAX 256
  36
  37 #undef SEM_FAILED
  38 #define SEM_FAILED ((sem_t *)(-1))
  39
  40 struct sema
  41 {
  42     struct Node node;
  43     int value;
  44     int waiters_count;
  45     pthread_mutex_t lock;
  46     pthread_cond_t count_nonzero;
  47 };
  48
  49 typedef struct sema sem_t;
  50
  51 #ifdef  __cplusplus
  52 extern "C" {
  53 #endif
  54
  55 int sem_init(sem_t *sem, int pshared, unsigned int value);
  56 int sem_destroy(sem_t *sem);
  57 int sem_trywait(sem_t *sem);
  58 int sem_wait(sem_t *sem);
  59 int sem_timedwait(sem_t *sem, const struct timespec *abstime);
  60 int sem_post(sem_t *sem);
  61 sem_t *sem_open(const char *name, int oflag, mode_t mode, unsigned int value);
  62 int sem_close(sem_t *sem);
  63 int sem_unlink(const char *name);
  64 int sem_getvalue(sem_t *sem, int *sval);
  65
  66 #ifdef  __cplusplus
  67 }
  68 #endif
  69
  70 #endif