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/fastd.c | 3 +-- src/fastd.h | 3 ++- src/sem.h | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ src/verify.c | 8 +++----- 4 files changed, 65 insertions(+), 8 deletions(-) create mode 100644 src/sem.h (limited to 'src') diff --git a/src/fastd.c b/src/fastd.c index b6e7484..e63b204 100644 --- a/src/fastd.c +++ b/src/fastd.c @@ -537,8 +537,7 @@ static inline void init(int argc, char *argv[]) { VECTOR_ALLOC(ctx.async_pids, 0); #ifdef WITH_VERIFY - if (sem_init(&ctx.verify_limit, 0, VERIFY_LIMIT)) - exit_errno("sem_init"); + fastd_sem_init(&ctx.verify_limit, VERIFY_LIMIT); #endif if (pthread_attr_init(&ctx.detached_thread)) diff --git a/src/fastd.h b/src/fastd.h index c52a690..7050f05 100644 --- a/src/fastd.h +++ b/src/fastd.h @@ -36,6 +36,7 @@ #include "dlist.h" #include "buffer.h" #include "log.h" +#include "sem.h" #include "shell.h" #include "vector.h" @@ -244,7 +245,7 @@ struct fastd_context { uint64_t next_peer_id; /**< An monotonously increasing ID peers are identified with in some components */ VECTOR(fastd_peer_t*) peers; /**< The currectly active peers */ #ifdef WITH_VERIFY - sem_t verify_limit; /**< Keeps track of the number of verifier threads */ + fastd_sem_t verify_limit; /**< Keeps track of the number of verifier threads */ #endif #ifdef USE_EPOLL 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); +} diff --git a/src/verify.c b/src/verify.c index 2031079..4f28faf 100644 --- a/src/verify.c +++ b/src/verify.c @@ -82,8 +82,7 @@ static void * do_verify_thread(void *p) { free(arg); - if (sem_post(&ctx.verify_limit)) - exit_errno("sem_post"); + fastd_sem_post(&ctx.verify_limit); return NULL; } @@ -110,7 +109,7 @@ fastd_tristate_t fastd_verify_peer(fastd_peer_t *peer, fastd_socket_t *sock, con return ret ? fastd_tristate_true : fastd_tristate_false; } else { - if (sem_trywait(&ctx.verify_limit)) { + if (!fastd_sem_trywait(&ctx.verify_limit)) { pr_debug("maximum number of verification processes reached"); return fastd_tristate_false; } @@ -131,8 +130,7 @@ fastd_tristate_t fastd_verify_peer(fastd_peer_t *peer, fastd_socket_t *sock, con if ((errno = pthread_create(&thread, &ctx.detached_thread, do_verify_thread, arg)) != 0) { pr_error_errno("unable to create verify thread"); - if (sem_post(&ctx.verify_limit)) - exit_errno("sem_post"); + fastd_sem_post(&ctx.verify_limit); fastd_shell_env_free(env); free(arg); -- cgit v1.2.3