/*
- * Copyright (C) 2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file ipc.c interprocess communication and shared memory helpers */
#include "ipc.h"
#include <sys/ipc.h>
#include <sys/shm.h>
-
-/** abort if semget() failed that many times */
-#define MAX_SEMOP_RETRIES 500
+#include <sys/sem.h>
/**
* define a new mutex
*
- * \return the identifier for the new mutex on success, -E_SEM_GET
+ * \return the identifier for the new mutex on success, \a -E_SEM_GET
* on errors.
*
* \sa semget(2)
/**
* destroy a mutex
*
- * \param, id the identifier of the mutex to be destroyed
+ * \param id the identifier of the mutex to be destroyed
*
- * \returns Positive on success, -E_SEM_REMOVE on errors.
+ * \return Positive on success, \a -E_SEM_REMOVE on errors.
*
* \sa semctl(2)
*/
static void para_semop(int id, struct sembuf *sops, int num)
{
- int i;
-
- for (i = 0; i < MAX_SEMOP_RETRIES; i++)
+ do {
if (semop(id, sops, num) >= 0)
return;
- PARA_EMERG_LOG("semop failed %d times, aborting\n", MAX_SEMOP_RETRIES);
+ } while (errno == EINTR);
+ if (errno == EIDRM) {
+ PARA_NOTICE_LOG("semaphore set %d was removed\n", id);
+ return;
+ }
+ PARA_EMERG_LOG("fatal semop error %s: pid %d\n", strerror(errno), getpid());
exit(EXIT_FAILURE);
}
/**
* lock the given mutex
*
+ * \param id of the shared memory area to lock
+ *
* This function either succeeds or aborts.
*
* \sa semop(2), struct misc_meta_data
/**
* create a new shared memory area of given size
- *
+ *
+ * \param size the size of the shared memory area to create
+ *
+ * \return The id of the shared memory areay on success, \a -E_SHM_GET on errors.
+ *
* \sa shmget(2)
*/
int shm_new(size_t size)
/**
* destroy the given shared memory area
+ *
+ * \param id the shared memory id
+ *
+ * \return The return value of the underlying shmctl() call on success,
+ * \a -E_SHM_DESTROY on errors.
+ *
* \sa shmctl(2)
- **/
+ */
int shm_destroy(int id)
{
struct shmid_ds shm_desc;
*
* \param id the identifier of the shared memory segment to attach
* \param mode either ATTACH_RO (read only) or ATTACH_RW (read/write)
- * \param result points to the attached arer which to the
+ * \param result points to the attached area just attached
*
- * \returns positive on success, -E_SHM_ATTACH on errrors.
+ * \return positive on success, \a -E_SHM_ATTACH on errors.
*
* \sa shmat(2)
*/
*
* \param addr the address of the attached segment
*
- * \returns positive on success, -E_SHM_DETACH on errors.
+ * \return positive on success, \a -E_SHM_DETACH on errors.
*
* \sa shmdt(2)
*/