X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=ipc.c;h=debf9d11be254ed6cf07d7dc390763cbc0f5fb8d;hp=49d2d96515dbf49bc5a9f7ace0786d5f68acc936;hb=5388ccac44e5342917ad50b091e9e4f906e3a4fc;hpb=7062b8a307355422f2c69b44b65f23eab17ce15d

diff --git a/ipc.c b/ipc.c
index 49d2d965..debf9d11 100644
--- a/ipc.c
+++ b/ipc.c
@@ -1,19 +1,7 @@
 /*
- * 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 */
@@ -25,13 +13,10 @@
 #include <sys/shm.h>
 #include <sys/sem.h>
 
-/** abort if semget() failed that many times */
-#define MAX_SEMOP_RETRIES 500
-
 /**
  * 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)
@@ -47,7 +32,7 @@ int mutex_new(void)
  *
  * \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)
  */
@@ -59,18 +44,23 @@ int mutex_destroy(int id)
 
 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
@@ -115,7 +105,11 @@ void mutex_unlock(int id)
 
 /**
  * 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)
@@ -126,8 +120,14 @@ 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;
@@ -140,9 +140,9 @@ int shm_destroy(int id)
  *
  * \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)
  */
@@ -161,7 +161,7 @@ int shm_attach(int id, enum shm_attach_mode mode, void **result)
  *
  * \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)
  */