[PATCH] posix message queues: syscall stubs

From: Manfred Spraul <manfred@colorfullife.com>

Add -ENOSYS stubs for the posix message queue syscalls.  The API is a direct
mapping of the api from the unix spec, with two exceptions:

- mq_close() doesn't exist.  Message queue file descriptors can be closed
  with close().

- mq_notify(SIGEV_THREAD) cannot be implemented in the kernel.  The kernel
  returns a pollable file descriptor .  User space must poll (or read) this
  descriptor and call the notifier function if the file descriptor is
  signaled.

arch/i386/kernel/entry.S

@@ -882,5 +882,14 @@ ENTRY(sys_call_table)
 	.long sys_utimes
  	.long sys_fadvise64_64
 	.long sys_ni_syscall	/* sys_vserver */
+	.long sys_ni_syscall	/* sys_mbind */
+	.long sys_ni_syscall	/* 275 sys_get_mempolicy */
+	.long sys_ni_syscall	/* sys_set_mempolicy */
+	.long sys_mq_open
+	.long sys_mq_unlink
+	.long sys_mq_timedsend
+	.long sys_mq_timedreceive	/* 280 */
+	.long sys_mq_notify
+	.long sys_mq_getsetattr
 
 syscall_table_size=(.-sys_call_table)

include/asm-i386/unistd.h

@@ -279,8 +279,17 @@
 #define __NR_utimes		271
 #define __NR_fadvise64_64	272
 #define __NR_vserver		273
+#define __NR_mbind		274
+#define __NR_get_mempolicy	275
+#define __NR_set_mempolicy	276
+#define __NR_mq_open 		277
+#define __NR_mq_unlink		(__NR_mq_open+1)
+#define __NR_mq_timedsend	(__NR_mq_open+2)
+#define __NR_mq_timedreceive	(__NR_mq_open+3)
+#define __NR_mq_notify		(__NR_mq_open+4)
+#define __NR_mq_getsetattr	(__NR_mq_open+5)
 
-#define NR_syscalls 274
+#define NR_syscalls 283
 
 /* user-visible error numbers are in the range -1 - -124: see <asm-i386/errno.h> */
 

include/linux/mqueue.h

+/* Copyright (C) 2003 Krzysztof Benedyczak & Michal Wronski
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   It 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this software; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _LINUX_MQUEUE_H
+#define _LINUX_MQUEUE_H
+
+#define MQ_PRIO_MAX 	32768
+
+typedef int mqd_t;
+
+struct mq_attr {
+	long	mq_flags;	/* message queue flags			*/
+	long	mq_maxmsg;	/* maximum number of messages		*/
+	long	mq_msgsize;	/* maximum message size			*/
+	long	mq_curmsgs;	/* number of messages currently queued	*/
+};
+
+#define NOTIFY_NONE	0
+#define NOTIFY_WOKENUP	1
+#define NOTIFY_REMOVED	2
+
+#endif

include/linux/syscalls.h

@@ -48,6 +48,8 @@ struct timex;
 struct timezone;
 struct tms;
 struct utimbuf;
+typedef int mqd_t;
+struct mq_attr;
 
 #include <linux/config.h>
 #include <linux/types.h>
@@ -450,6 +452,13 @@ asmlinkage long sys_shmget(key_t key, size_t size, int flag);
 asmlinkage long sys_shmdt(char __user *shmaddr);
 asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);
 
+asmlinkage long sys_mq_open(const char __user *name, int oflag, mode_t mode, struct mq_attr __user *attr);
+asmlinkage long sys_mq_unlink(const char __user *name);
+asmlinkage long sys_mq_timedsend(mqd_t mqdes, const char __user *msg_ptr, size_t msg_len, unsigned int msg_prio, const struct timespec __user *abs_timeout);
+asmlinkage ssize_t sys_mq_timedreceive(mqd_t mqdes, char __user *msg_ptr, size_t msg_len, unsigned int __user *msg_prio, const struct timespec __user *abs_timeout);
+asmlinkage long sys_mq_notify(mqd_t mqdes, const struct sigevent __user *notification);
+asmlinkage long sys_mq_getsetattr(mqd_t mqdes, const struct mq_attr __user *mqstat, struct mq_attr __user *omqstat);
+
 asmlinkage long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn);
 asmlinkage long sys_pciconfig_read(unsigned long bus, unsigned long dfn,
 				unsigned long off, unsigned long len,

kernel/sys.c

@@ -260,6 +260,12 @@ cond_syscall(sys_msgctl)
 cond_syscall(sys_shmget)
 cond_syscall(sys_shmdt)
 cond_syscall(sys_shmctl)
+cond_syscall(sys_mq_open)
+cond_syscall(sys_mq_unlink)
+cond_syscall(sys_mq_timedsend)
+cond_syscall(sys_mq_timedreceive)
+cond_syscall(sys_mq_notify)
+cond_syscall(sys_mq_getsetattr)
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read)