From 4f25bdd2590f65586931ec71f798a91443e13674 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Sat, 2 Aug 2014 06:44:34 +0200 Subject: Encapsulate semaphore handling --- src/sem.h | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 src/sem.h (limited to 'src/sem.h') diff --git a/src/sem.h b/src/sem.h new file mode 100644 index 0000000..f0b7183 --- /dev/null +++ b/src/sem.h @@ -0,0 +1,59 @@ +/* + Copyright (c) 2012-2014, Matthias Schiffer + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + 2. Redistributions in binary form must reproduce the above copyright notice, + this list of conditions and the following disclaimer in the documentation + and/or other materials provided with the distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +/** + \file + + Portable semapores +*/ + + +#pragma once + +#include "log.h" + +#include + + +/** Generic semaphore type */ +typedef sem_t fastd_sem_t; + + +/** Initializes a semaphore with a given value */ +static inline void fastd_sem_init(fastd_sem_t *sem, unsigned value) { + if (sem_init(sem, 0, value)) + exit_errno("sem_init"); +} + +/** Increments the semaphore */ +static inline void fastd_sem_post(fastd_sem_t *sem) { + if (sem_post(sem)) + exit_errno("sem_post"); +} + +/** Tries to decrement the semaphore */ +static inline bool fastd_sem_trywait(fastd_sem_t *sem) { + return !sem_trywait(sem); +} -- cgit v1.2.3