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diff --git a/src/zix/sem.h b/src/zix/sem.h
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-/*
- Copyright 2012-2014 David Robillard <http://drobilla.net>
-
- Permission to use, copy, modify, and/or distribute this software for any
- purpose with or without fee is hereby granted, provided that the above
- copyright notice and this permission notice appear in all copies.
-
- THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-
-#ifndef ZIX_SEM_H
-#define ZIX_SEM_H
-
-#include "zix/common.h"
-
-#ifdef __APPLE__
-# include <mach/mach.h>
-#elif defined(_WIN32)
-# include <limits.h>
-# include <windows.h>
-#else
-# include <semaphore.h>
-# include <errno.h>
-#endif
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
- @addtogroup zix
- @{
- @name Semaphore
- @{
-*/
-
-/**
- A counting semaphore.
-
- This is an integer that is always positive, and has two main operations:
- increment (post) and decrement (wait). If a decrement can not be performed
- (i.e. the value is 0) the caller will be blocked until another thread posts
- and the operation can succeed.
-
- Semaphores can be created with any starting value, but typically this will
- be 0 so the semaphore can be used as a simple signal where each post
- corresponds to one wait.
-
- Semaphores are very efficient (much moreso than a mutex/cond pair). In
- particular, at least on Linux, post is async-signal-safe, which means it
- does not block and will not be interrupted. If you need to signal from
- a realtime thread, this is the most appropriate primitive to use.
-*/
-typedef struct ZixSemImpl ZixSem;
-
-/**
- Create and initialize `sem` to `initial`.
-*/
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial);
-
-/**
- Destroy `sem`.
-*/
-static inline void
-zix_sem_destroy(ZixSem* sem);
-
-/**
- Increment (and signal any waiters).
- Realtime safe.
-*/
-static inline void
-zix_sem_post(ZixSem* sem);
-
-/**
- Wait until count is > 0, then decrement.
- Obviously not realtime safe.
-*/
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem);
-
-/**
- Non-blocking version of wait().
-
- @return true if decrement was successful (lock was acquired).
-*/
-static inline bool
-zix_sem_try_wait(ZixSem* sem);
-
-/**
- @cond
-*/
-
-#ifdef __APPLE__
-
-struct ZixSemImpl {
- semaphore_t sem;
-};
-
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned val)
-{
- return semaphore_create(mach_task_self(), &sem->sem, SYNC_POLICY_FIFO, val)
- ? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-static inline void
-zix_sem_destroy(ZixSem* sem)
-{
- semaphore_destroy(mach_task_self(), sem->sem);
-}
-
-static inline void
-zix_sem_post(ZixSem* sem)
-{
- semaphore_signal(sem->sem);
-}
-
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem)
-{
- if (semaphore_wait(sem->sem) != KERN_SUCCESS) {
- return ZIX_STATUS_ERROR;
- }
- return ZIX_STATUS_SUCCESS;
-}
-
-static inline bool
-zix_sem_try_wait(ZixSem* sem)
-{
- const mach_timespec_t zero = { 0, 0 };
- return semaphore_timedwait(sem->sem, zero) == KERN_SUCCESS;
-}
-
-#elif defined(_WIN32)
-
-struct ZixSemImpl {
- HANDLE sem;
-};
-
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial)
-{
- sem->sem = CreateSemaphore(NULL, initial, LONG_MAX, NULL);
- return (sem->sem) ? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-static inline void
-zix_sem_destroy(ZixSem* sem)
-{
- CloseHandle(sem->sem);
-}
-
-static inline void
-zix_sem_post(ZixSem* sem)
-{
- ReleaseSemaphore(sem->sem, 1, NULL);
-}
-
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem)
-{
- if (WaitForSingleObject(sem->sem, INFINITE) != WAIT_OBJECT_0) {
- return ZIX_STATUS_ERROR;
- }
- return ZIX_STATUS_SUCCESS;
-}
-
-static inline bool
-zix_sem_try_wait(ZixSem* sem)
-{
- return WaitForSingleObject(sem->sem, 0) == WAIT_OBJECT_0;
-}
-
-#else /* !defined(__APPLE__) && !defined(_WIN32) */
-
-struct ZixSemImpl {
- sem_t sem;
-};
-
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial)
-{
- return sem_init(&sem->sem, 0, initial)
- ? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-static inline void
-zix_sem_destroy(ZixSem* sem)
-{
- sem_destroy(&sem->sem);
-}
-
-static inline void
-zix_sem_post(ZixSem* sem)
-{
- sem_post(&sem->sem);
-}
-
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem)
-{
- while (sem_wait(&sem->sem)) {
- if (errno != EINTR) {
- return ZIX_STATUS_ERROR;
- }
- /* Otherwise, interrupted, so try again. */
- }
-
- return ZIX_STATUS_SUCCESS;
-}
-
-static inline bool
-zix_sem_try_wait(ZixSem* sem)
-{
- return (sem_trywait(&sem->sem) == 0);
-}
-
-#endif
-
-/**
- @endcond
- @}
- @}
-*/
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#endif /* ZIX_SEM_H */