1211 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			1211 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			C++
		
	
	
	
| /*
 | |
|  * Implementation of SVID messages
 | |
|  *
 | |
|  * Author:  Daniel Boulet
 | |
|  *
 | |
|  * Copyright 1993 Daniel Boulet and RTMX Inc.
 | |
|  *
 | |
|  * This system call was implemented by Daniel Boulet under contract from RTMX.
 | |
|  *
 | |
|  * Redistribution and use in source forms, with and without modification,
 | |
|  * are permitted provided that this entire comment appears intact.
 | |
|  *
 | |
|  * Redistribution in binary form may occur without any restrictions.
 | |
|  * Obviously, it would be nice if you gave credit where credit is due
 | |
|  * but requiring it would be too onerous.
 | |
|  *
 | |
|  * This software is provided ``AS IS'' without any warranties of any kind.
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  * This file is heavily changed to become part of Cygwin's cygserver.
 | |
|  */
 | |
| 
 | |
| #ifdef __OUTSIDE_CYGWIN__
 | |
| #include "woutsup.h"
 | |
| #include <sys/cdefs.h>
 | |
| #ifndef __FBSDID
 | |
| #define __FBSDID(s)	const char version[] = (s)
 | |
| #endif
 | |
| __FBSDID("$FreeBSD: /usr/local/www/cvsroot/FreeBSD/src/sys/kern/sysv_msg.c,v 1.52 2003/11/07 04:47:14 rwatson Exp $");
 | |
| 
 | |
| #define _KERNEL 1
 | |
| #define __BSD_VISIBLE 1
 | |
| #include <sys/types.h>
 | |
| #include <sys/sysproto.h>
 | |
| #include <sys/ipc.h>
 | |
| #include <sys/param.h>
 | |
| #include <sys/msg.h>
 | |
| #include <malloc.h>
 | |
| #include <errno.h>
 | |
| #include <time.h>
 | |
| #include "cygserver.h"
 | |
| #include "process.h"
 | |
| #include "cygserver_ipc.h"
 | |
| 
 | |
| #ifdef __CYGWIN__
 | |
| #define MSG_DEBUG
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| #ifdef MSG_DEBUG
 | |
| #define DPRINTF(a)	debug_printf a
 | |
| #else
 | |
| #define DPRINTF(a)
 | |
| #endif
 | |
| 
 | |
| static void msg_freehdr(struct msg *msghdr);
 | |
| 
 | |
| #ifndef __CYGWIN__
 | |
| int msgctl(struct thread *, struct msgctl_args *);
 | |
| int msgget(struct thread *, struct msgget_args *);
 | |
| int msgsnd(struct thread *, struct msgsnd_args *);
 | |
| int msgrcv(struct thread *, struct msgrcv_args *);
 | |
| 
 | |
| static sy_call_t *msgcalls[] = {
 | |
| 	(sy_call_t *)msgctl, (sy_call_t *)msgget,
 | |
| 	(sy_call_t *)msgsnd, (sy_call_t *)msgrcv
 | |
| };
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| 
 | |
| struct msg {
 | |
| 	struct	msg *msg_next;	/* next msg in the chain */
 | |
| 	long	msg_type;	/* type of this message */
 | |
|     				/* >0 -> type of this message */
 | |
|     				/* 0 -> free header */
 | |
| 	u_short	msg_ts;		/* size of this message */
 | |
| 	short	msg_spot;	/* location of start of msg in buffer */
 | |
| };
 | |
| 
 | |
| 
 | |
| #ifndef MSGSSZ
 | |
| #define MSGSSZ	8		/* Each segment must be 2^N long */
 | |
| #endif
 | |
| #ifndef MSGSEG
 | |
| #define MSGSEG	2048		/* must be less than 32767 */
 | |
| #endif
 | |
| #define MSGMAX	(MSGSSZ*MSGSEG)
 | |
| #ifndef MSGMNB
 | |
| #define MSGMNB	2048		/* max # of bytes in a queue */
 | |
| #endif
 | |
| #ifndef MSGMNI
 | |
| #define MSGMNI	40
 | |
| #endif
 | |
| #ifndef MSGTQL
 | |
| #define MSGTQL	40
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * Based on the configuration parameters described in an SVR2 (yes, two)
 | |
|  * config(1m) man page.
 | |
|  *
 | |
|  * Each message is broken up and stored in segments that are msgssz bytes
 | |
|  * long.  For efficiency reasons, this should be a power of two.  Also,
 | |
|  * it doesn't make sense if it is less than 8 or greater than about 256.
 | |
|  * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
 | |
|  * two between 8 and 1024 inclusive (and panic's if it isn't).
 | |
|  */
 | |
| struct msginfo msginfo = {
 | |
|                 MSGMAX,         /* max chars in a message */
 | |
|                 MSGMNB,         /* max chars in a queue */
 | |
|                 MSGMNI,         /* # of message queue identifiers */
 | |
|                 MSGTQL,         /* max messages in system */
 | |
|                 MSGSSZ,         /* size of a message segment */
 | |
|                 		/* (must be small power of 2 greater than 4) */
 | |
|                 MSGSEG          /* number of message segments */
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * macros to convert between msqid_ds's and msqid's.
 | |
|  * (specific to this implementation)
 | |
|  */
 | |
| #define MSQID(ix,ds)	((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
 | |
| #define MSQID_IX(id)	((id) & 0xffff)
 | |
| #define MSQID_SEQ(id)	(((id) >> 16) & 0xffff)
 | |
| 
 | |
| /*
 | |
|  * The rest of this file is specific to this particular implementation.
 | |
|  */
 | |
| 
 | |
| struct msgmap {
 | |
| 	short	next;		/* next segment in buffer */
 | |
|     				/* -1 -> available */
 | |
|     				/* 0..(MSGSEG-1) -> index of next segment */
 | |
| };
 | |
| 
 | |
| #define MSG_LOCKED	01000	/* Is this msqid_ds locked? */
 | |
| 
 | |
| static int nfree_msgmaps;	/* # of free map entries */
 | |
| static short free_msgmaps;	/* head of linked list of free map entries */
 | |
| static struct msg *free_msghdrs;/* list of free msg headers */
 | |
| static char *msgpool;		/* MSGMAX byte long msg buffer pool */
 | |
| static struct msgmap *msgmaps;	/* MSGSEG msgmap structures */
 | |
| static struct msg *msghdrs;	/* MSGTQL msg headers */
 | |
| static struct msqid_ds *msqids;	/* MSGMNI msqid_ds struct's */
 | |
| static struct mtx msq_mtx;	/* global mutex for message queues. */
 | |
| 
 | |
| #ifdef __CYGWIN__
 | |
| static struct msg_info msg_info;
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| void
 | |
| msginit()
 | |
| {
 | |
| 	int i;
 | |
| 
 | |
| 	TUNABLE_INT_FETCH("kern.ipc.msgseg", &msginfo.msgseg);
 | |
| 	TUNABLE_INT_FETCH("kern.ipc.msgssz", &msginfo.msgssz);
 | |
| 	msginfo.msgmax = msginfo.msgseg * msginfo.msgssz;
 | |
| 	TUNABLE_INT_FETCH("kern.ipc.msgmnb", &msginfo.msgmnb);
 | |
| 	TUNABLE_INT_FETCH("kern.ipc.msgmni", &msginfo.msgmni);
 | |
| 	TUNABLE_INT_FETCH("kern.ipc.msgtql", &msginfo.msgtql);
 | |
| 
 | |
| 	msgpool = (char *) sys_malloc(msginfo.msgmax, M_MSG, M_WAITOK);
 | |
| 	if (msgpool == NULL)
 | |
| 		panic("msgpool is NULL");
 | |
| 	msgmaps = (msgmap *) sys_malloc(sizeof(struct msgmap) * msginfo.msgseg, M_MSG, M_WAITOK);
 | |
| 	if (msgmaps == NULL)
 | |
| 		panic("msgmaps is NULL");
 | |
| 	msghdrs = (msg *) sys_malloc(sizeof(struct msg) * msginfo.msgtql, M_MSG, M_WAITOK);
 | |
| 	if (msghdrs == NULL)
 | |
| 		panic("msghdrs is NULL");
 | |
| 	msqids = (msqid_ds *) sys_malloc(sizeof(struct msqid_ds) * msginfo.msgmni, M_MSG, M_WAITOK);
 | |
| 	if (msqids == NULL)
 | |
| 		panic("msqids is NULL");
 | |
| 
 | |
| 	/*
 | |
| 	 * msginfo.msgssz should be a power of two for efficiency reasons.
 | |
| 	 * It is also pretty silly if msginfo.msgssz is less than 8
 | |
| 	 * or greater than about 256 so ...
 | |
| 	 */
 | |
| 
 | |
| 	i = 8;
 | |
| 	while (i < 1024 && i != msginfo.msgssz)
 | |
| 		i <<= 1;
 | |
|     	if (i != msginfo.msgssz) {
 | |
| 		DPRINTF(("msginfo.msgssz=%d (0x%x)\n", msginfo.msgssz,
 | |
| 		    msginfo.msgssz));
 | |
| 		panic("msginfo.msgssz not a small power of 2");
 | |
| 	}
 | |
| 
 | |
| 	if (msginfo.msgseg > 32767) {
 | |
| 		DPRINTF(("msginfo.msgseg=%d\n", msginfo.msgseg));
 | |
| 		panic("msginfo.msgseg > 32767");
 | |
| 	}
 | |
| 
 | |
| 	if (msgmaps == NULL)
 | |
| 		panic("msgmaps is NULL");
 | |
| 
 | |
| 	for (i = 0; i < msginfo.msgseg; i++) {
 | |
| 		if (i > 0)
 | |
| 			msgmaps[i-1].next = i;
 | |
| 		msgmaps[i].next = -1;	/* implies entry is available */
 | |
| 	}
 | |
| 	free_msgmaps = 0;
 | |
| 	nfree_msgmaps = msginfo.msgseg;
 | |
| 
 | |
| 	if (msghdrs == NULL)
 | |
| 		panic("msghdrs is NULL");
 | |
| 
 | |
| 	for (i = 0; i < msginfo.msgtql; i++) {
 | |
| 		msghdrs[i].msg_type = 0;
 | |
| 		if (i > 0)
 | |
| 			msghdrs[i-1].msg_next = &msghdrs[i];
 | |
| 		msghdrs[i].msg_next = NULL;
 | |
|     	}
 | |
| 	free_msghdrs = &msghdrs[0];
 | |
| 
 | |
| 	if (msqids == NULL)
 | |
| 		panic("msqids is NULL");
 | |
| 
 | |
| 	for (i = 0; i < msginfo.msgmni; i++) {
 | |
| 		msqids[i].msg_qbytes = 0;	/* implies entry is available */
 | |
| 		msqids[i].msg_perm.seq = 0;	/* reset to a known value */
 | |
| 		msqids[i].msg_perm.mode = 0;
 | |
| 	}
 | |
| 	mtx_init(&msq_mtx, "msq", NULL, MTX_DEF);
 | |
| }
 | |
| 
 | |
| int
 | |
| msgunload()
 | |
| {
 | |
| 	struct msqid_ds *msqptr;
 | |
| 	int msqid;
 | |
| 
 | |
| 	for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
 | |
| 		/*
 | |
| 		 * Look for an unallocated and unlocked msqid_ds.
 | |
| 		 * msqid_ds's can be locked by msgsnd or msgrcv while
 | |
| 		 * they are copying the message in/out.  We can't
 | |
| 		 * re-use the entry until they release it.
 | |
| 		 */
 | |
| 		msqptr = &msqids[msqid];
 | |
| 		if (msqptr->msg_qbytes != 0 ||
 | |
| 		    (msqptr->msg_perm.mode & MSG_LOCKED) != 0)
 | |
| 			break;
 | |
| 	}
 | |
| #ifndef __CYGWIN__
 | |
| 	if (msqid != msginfo.msgmni)
 | |
| 		return (EBUSY);
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| 	sys_free(msgpool, M_MSG);
 | |
| 	sys_free(msgmaps, M_MSG);
 | |
| 	sys_free(msghdrs, M_MSG);
 | |
| 	sys_free(msqids, M_MSG);
 | |
| 	mtx_destroy(&msq_mtx);
 | |
| 	return (0);
 | |
| }
 | |
| 
 | |
| 
 | |
| #ifndef __CYGWIN__
 | |
| static int
 | |
| sysvmsg_modload(struct module *module, int cmd, void *arg)
 | |
| {
 | |
| 	int error = 0;
 | |
| 
 | |
| 	switch (cmd) {
 | |
| 	case MOD_LOAD:
 | |
| 		msginit();
 | |
| 		break;
 | |
| 	case MOD_UNLOAD:
 | |
| 		error = msgunload();
 | |
| 		break;
 | |
| 	case MOD_SHUTDOWN:
 | |
| 		break;
 | |
| 	default:
 | |
| 		error = EINVAL;
 | |
| 		break;
 | |
| 	}
 | |
| 	return (error);
 | |
| }
 | |
| 
 | |
| static moduledata_t sysvmsg_mod = {
 | |
| 	"sysvmsg",
 | |
| 	&sysvmsg_modload,
 | |
| 	NULL
 | |
| };
 | |
| 
 | |
| SYSCALL_MODULE_HELPER(msgsys);
 | |
| SYSCALL_MODULE_HELPER(msgctl);
 | |
| SYSCALL_MODULE_HELPER(msgget);
 | |
| SYSCALL_MODULE_HELPER(msgsnd);
 | |
| SYSCALL_MODULE_HELPER(msgrcv);
 | |
| 
 | |
| DECLARE_MODULE(sysvmsg, sysvmsg_mod,
 | |
| 	SI_SUB_SYSV_MSG, SI_ORDER_FIRST);
 | |
| MODULE_VERSION(sysvmsg, 1);
 | |
| 
 | |
| /*
 | |
|  * Entry point for all MSG calls
 | |
|  *
 | |
|  * MPSAFE
 | |
|  */
 | |
| int
 | |
| msgsys(thread *td, struct msgsys_args *uap)
 | |
| {
 | |
| 	int error;
 | |
| 
 | |
| 	if (!jail_sysvipc_allowed && jailed(td->td_ucred))
 | |
| 		return (ENOSYS);
 | |
| 	if (uap->which < 0 ||
 | |
| 	    (unsigned) uap->which >= sizeof(msgcalls)/sizeof(msgcalls[0]))
 | |
| 		return (EINVAL);
 | |
| 	error = (*msgcalls[uap->which])(td, &uap->a2);
 | |
| 	return (error);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static void
 | |
| msg_freehdr(struct msg *msghdr)
 | |
| {
 | |
| 	while (msghdr->msg_ts > 0) {
 | |
| 		short next;
 | |
| 		if (msghdr->msg_spot < 0 || msghdr->msg_spot >= msginfo.msgseg)
 | |
| 			panic("msghdr->msg_spot out of range");
 | |
| 		next = msgmaps[msghdr->msg_spot].next;
 | |
| 		msgmaps[msghdr->msg_spot].next = free_msgmaps;
 | |
| 		free_msgmaps = msghdr->msg_spot;
 | |
| 		nfree_msgmaps++;
 | |
| 		msghdr->msg_spot = next;
 | |
| 		if (msghdr->msg_ts >= msginfo.msgssz)
 | |
| 			msghdr->msg_ts -= msginfo.msgssz;
 | |
| 		else
 | |
| 			msghdr->msg_ts = 0;
 | |
| 	}
 | |
| 	if (msghdr->msg_spot != -1)
 | |
| 		panic("msghdr->msg_spot != -1");
 | |
| 	msghdr->msg_next = free_msghdrs;
 | |
| 	free_msghdrs = msghdr;
 | |
| }
 | |
| 
 | |
| #ifndef _SYS_SYSPROTO_H_
 | |
| struct msgctl_args {
 | |
| 	int	msqid;
 | |
| 	int	cmd;
 | |
| 	struct	msqid_ds *buf;
 | |
| };
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * MPSAFE
 | |
|  */
 | |
| int
 | |
| msgctl(struct thread *td, struct msgctl_args *uap)
 | |
| {
 | |
| 	int msqid = uap->msqid;
 | |
| 	int cmd = uap->cmd;
 | |
| 	struct msqid_ds *user_msqptr = uap->buf;
 | |
| 	int rval, error;
 | |
| 	struct msqid_ds msqbuf;
 | |
| 	register struct msqid_ds *msqptr;
 | |
| 
 | |
| 	DPRINTF(("call to msgctl(%d, %d, 0x%x)\n", msqid, cmd, user_msqptr));
 | |
| 
 | |
| 	if (!jail_sysvipc_allowed && jailed(td->td_ucred))
 | |
| 		return (ENOSYS);
 | |
| 
 | |
| #ifdef __CYGWIN__
 | |
| 	if (cmd == IPC_INFO) {
 | |
| 		if (!msqid) {
 | |
| 			error = copyout(&msginfo, user_msqptr,
 | |
| 					sizeof(struct msginfo));
 | |
| 			td->td_retval[0] = error ? -1 : 0;
 | |
| 			return (error);
 | |
| 		}
 | |
| 		if (msqid > msginfo.msgmni)
 | |
| 			msqid = msginfo.msgmni;
 | |
| 		error = copyout(msqids, user_msqptr,
 | |
| 				msqid * sizeof(struct msqid_ds));
 | |
| 		td->td_retval[0] = error ? -1 : 0;
 | |
| 		return (error);
 | |
| 	} else if (cmd == MSG_INFO) {
 | |
| 		mtx_lock(&msq_mtx);
 | |
| 		error = copyout(&msg_info, user_msqptr,
 | |
| 				sizeof(struct msg_info));
 | |
| 		td->td_retval[0] = error ? -1 : 0;
 | |
| 		mtx_unlock(&msq_mtx);
 | |
| 		return (error);
 | |
| 	}
 | |
| #endif /* __CYGWIN__ */
 | |
| 	msqid = IPCID_TO_IX(msqid);
 | |
| 
 | |
| 	if (msqid < 0 || msqid >= msginfo.msgmni) {
 | |
| 		DPRINTF(("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
 | |
| 		    msginfo.msgmni));
 | |
| 		return (EINVAL);
 | |
| 	}
 | |
| 	if (cmd == IPC_SET &&
 | |
| 	    (error = copyin(user_msqptr, &msqbuf, sizeof(msqbuf))) != 0)
 | |
| 		return (error);
 | |
| 
 | |
| 	msqptr = &msqids[msqid];
 | |
| 
 | |
| 	mtx_lock(&msq_mtx);
 | |
| 	if (msqptr->msg_qbytes == 0) {
 | |
| 		DPRINTF(("no such msqid\n"));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 	if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
 | |
| 		DPRINTF(("wrong sequence number\n"));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	error = 0;
 | |
| 	rval = 0;
 | |
| 
 | |
| 	switch (cmd) {
 | |
| 
 | |
| 	case IPC_RMID:
 | |
| 	{
 | |
| 		struct msg *msghdr;
 | |
| 		if ((error = ipcperm(td, &msqptr->msg_perm, IPC_M)))
 | |
| 			goto done2;
 | |
| 		/* Free the message headers */
 | |
| 		msghdr = msqptr->msg_first;
 | |
| 		while (msghdr != NULL) {
 | |
| 			struct msg *msghdr_tmp;
 | |
| 
 | |
| 			/* Free the segments of each message */
 | |
| 			msqptr->msg_cbytes -= msghdr->msg_ts;
 | |
| 			msqptr->msg_qnum--;
 | |
| 			msghdr_tmp = msghdr;
 | |
| 			msghdr = msghdr->msg_next;
 | |
| 			msg_freehdr(msghdr_tmp);
 | |
| 		}
 | |
| 
 | |
| 		if (msqptr->msg_cbytes != 0)
 | |
| 			panic("msg_cbytes is screwed up");
 | |
| 		if (msqptr->msg_qnum != 0)
 | |
| 			panic("msg_qnum is screwed up");
 | |
| 
 | |
| 		msqptr->msg_qbytes = 0;	/* Mark it as free */
 | |
| #ifdef __CYGWIN__
 | |
| 		msg_info.msg_ids--;
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| 		wakeup(msqptr);
 | |
| 	}
 | |
| 
 | |
| 		break;
 | |
| 
 | |
| 	case IPC_SET:
 | |
| 		if ((error = ipcperm(td, &msqptr->msg_perm, IPC_M)))
 | |
| 			goto done2;
 | |
| 		if (msqbuf.msg_qbytes > msqptr->msg_qbytes) {
 | |
| 			error = suser(td);
 | |
| 			if (error)
 | |
| 				goto done2;
 | |
| 		}
 | |
| 		if (msqbuf.msg_qbytes > (unsigned long) msginfo.msgmnb) {
 | |
| 			DPRINTF(("can't increase msg_qbytes beyond %d"
 | |
| 			    "(truncating)\n", msginfo.msgmnb));
 | |
| 			msqbuf.msg_qbytes = msginfo.msgmnb;	/* silently restrict qbytes to system limit */
 | |
| 		}
 | |
| 		if (msqbuf.msg_qbytes == 0) {
 | |
| 			DPRINTF(("can't reduce msg_qbytes to 0\n"));
 | |
| 			error = EINVAL;		/* non-standard errno! */
 | |
| 			goto done2;
 | |
| 		}
 | |
| 		msqptr->msg_perm.uid = msqbuf.msg_perm.uid;	/* change the owner */
 | |
| 		msqptr->msg_perm.gid = msqbuf.msg_perm.gid;	/* change the owner */
 | |
| 		msqptr->msg_perm.mode = (msqptr->msg_perm.mode & ~0777) |
 | |
| 		    (msqbuf.msg_perm.mode & 0777);
 | |
| 		msqptr->msg_qbytes = msqbuf.msg_qbytes;
 | |
| 		msqptr->msg_ctime = time (NULL);
 | |
| 		break;
 | |
| 
 | |
| 	case IPC_STAT:
 | |
| 		if ((error = ipcperm(td, &msqptr->msg_perm, IPC_R))) {
 | |
| 			DPRINTF(("requester doesn't have read access\n"));
 | |
| 			goto done2;
 | |
| 		}
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 		DPRINTF(("invalid command %d\n", cmd));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	if (error == 0)
 | |
| 		td->td_retval[0] = rval;
 | |
| done2:
 | |
| 	mtx_unlock(&msq_mtx);
 | |
| 	if (cmd == IPC_STAT && error == 0)
 | |
| 		error = copyout(msqptr, user_msqptr, sizeof(struct msqid_ds));
 | |
| 	return(error);
 | |
| }
 | |
| 
 | |
| #ifndef _SYS_SYSPROTO_H_
 | |
| struct msgget_args {
 | |
| 	key_t	key;
 | |
| 	int	msgflg;
 | |
| };
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * MPSAFE
 | |
|  */
 | |
| int
 | |
| msgget(struct thread *td, struct msgget_args *uap)
 | |
| {
 | |
| 	int msqid, error = 0;
 | |
| 	key_t key = uap->key;
 | |
| 	unsigned msgflg = uap->msgflg;
 | |
| 	register struct msqid_ds *msqptr = NULL;
 | |
| 
 | |
| 	DPRINTF(("msgget(0x%x, 0%o)\n", key, msgflg));
 | |
| 
 | |
| 	if (!jail_sysvipc_allowed && jailed(td->td_ucred))
 | |
| 		return (ENOSYS);
 | |
| 
 | |
| 	mtx_lock(&msq_mtx);
 | |
| 	if (key != IPC_PRIVATE) {
 | |
| 		for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
 | |
| 			msqptr = &msqids[msqid];
 | |
| 			if (msqptr->msg_qbytes != 0 &&
 | |
| 			    msqptr->msg_perm.key == key)
 | |
| 				break;
 | |
| 		}
 | |
| 		if (msqid < msginfo.msgmni) {
 | |
| 			DPRINTF(("found public key\n"));
 | |
| 			if ((msgflg & IPC_CREAT) && (msgflg & IPC_EXCL)) {
 | |
| 				DPRINTF(("not exclusive\n"));
 | |
| 				error = EEXIST;
 | |
| 				goto done2;
 | |
| 			}
 | |
| 			if ((error = ipcperm(td, &msqptr->msg_perm, msgflg & 0700))) {
 | |
| 				DPRINTF(("requester doesn't have 0%o access\n",
 | |
| 				    msgflg & 0700));
 | |
| 				goto done2;
 | |
| 			}
 | |
| 			goto found;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	DPRINTF(("need to allocate the msqid_ds\n"));
 | |
| 	if (key == IPC_PRIVATE || (msgflg & IPC_CREAT)) {
 | |
| 		for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
 | |
| 			/*
 | |
| 			 * Look for an unallocated and unlocked msqid_ds.
 | |
| 			 * msqid_ds's can be locked by msgsnd or msgrcv while
 | |
| 			 * they are copying the message in/out.  We can't
 | |
| 			 * re-use the entry until they release it.
 | |
| 			 */
 | |
| 			msqptr = &msqids[msqid];
 | |
| 			if (msqptr->msg_qbytes == 0 &&
 | |
| 			    (msqptr->msg_perm.mode & MSG_LOCKED) == 0)
 | |
| 				break;
 | |
| 		}
 | |
| 		if (msqid == msginfo.msgmni) {
 | |
| 			DPRINTF(("no more msqid_ds's available\n"));
 | |
| 			error = ENOSPC;
 | |
| 			goto done2;
 | |
| 		}
 | |
| 		DPRINTF(("msqid %d is available\n", msqid));
 | |
| 		msqptr->msg_perm.key = key;
 | |
| #ifdef __CYGWIN__
 | |
| 		msqptr->msg_perm.cuid = td->ipcblk->uid;
 | |
| 		msqptr->msg_perm.uid = td->ipcblk->uid;
 | |
| 		msqptr->msg_perm.cgid = td->ipcblk->gid;
 | |
| 		msqptr->msg_perm.gid = td->ipcblk->gid;
 | |
| #else
 | |
| 		msqptr->msg_perm.cuid = cred->cr_uid;
 | |
| 		msqptr->msg_perm.uid = cred->cr_uid;
 | |
| 		msqptr->msg_perm.cgid = cred->cr_gid;
 | |
| 		msqptr->msg_perm.gid = cred->cr_gid;
 | |
| #endif /* __CYGWIN__ */
 | |
| 		msqptr->msg_perm.mode = (msgflg & 0777);
 | |
| 		/* Make sure that the returned msqid is unique */
 | |
| 		msqptr->msg_perm.seq = (msqptr->msg_perm.seq + 1) & 0x7fff;
 | |
| 		msqptr->msg_first = NULL;
 | |
| 		msqptr->msg_last = NULL;
 | |
| 		msqptr->msg_cbytes = 0;
 | |
| 		msqptr->msg_qnum = 0;
 | |
| 		msqptr->msg_qbytes = msginfo.msgmnb;
 | |
| 		msqptr->msg_lspid = 0;
 | |
| 		msqptr->msg_lrpid = 0;
 | |
| 		msqptr->msg_stime = 0;
 | |
| 		msqptr->msg_rtime = 0;
 | |
| 		msqptr->msg_ctime = time (NULL);
 | |
| #ifdef __CYGWIN__
 | |
| 		msg_info.msg_ids++;
 | |
| #endif /* __CYGWIN__ */
 | |
| 	} else {
 | |
| 		DPRINTF(("didn't find it and wasn't asked to create it\n"));
 | |
| 		error = ENOENT;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| found:
 | |
| 	/* Construct the unique msqid */
 | |
| 	td->td_retval[0] = IXSEQ_TO_IPCID(msqid, msqptr->msg_perm);
 | |
| done2:
 | |
| 	mtx_unlock(&msq_mtx);
 | |
| 	return (error);
 | |
| }
 | |
| 
 | |
| #ifndef _SYS_SYSPROTO_H_
 | |
| struct msgsnd_args {
 | |
| 	int	msqid;
 | |
| 	const void	*msgp;
 | |
| 	size_t	msgsz;
 | |
| 	int	msgflg;
 | |
| };
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * MPSAFE
 | |
|  */
 | |
| int
 | |
| msgsnd(struct thread *td, struct msgsnd_args *uap)
 | |
| {
 | |
| 	int msqid = uap->msqid;
 | |
| 	const void *user_msgp = uap->msgp;
 | |
| 	size_t msgsz = uap->msgsz;
 | |
| 	int msgflg = uap->msgflg;
 | |
| 	int segs_needed, error = 0;
 | |
| 	register struct msqid_ds *msqptr;
 | |
| 	register struct msg *msghdr;
 | |
| 	short next;
 | |
| 
 | |
| 	DPRINTF(("call to msgsnd(%d, 0x%x, %d, %d)\n", msqid, user_msgp, msgsz,
 | |
| 	    msgflg));
 | |
| 
 | |
| 	if (!jail_sysvipc_allowed && jailed(td->td_ucred))
 | |
| 		return (ENOSYS);
 | |
| 
 | |
| 	mtx_lock(&msq_mtx);
 | |
| 	msqid = IPCID_TO_IX(msqid);
 | |
| 
 | |
| 	if (msqid < 0 || msqid >= msginfo.msgmni) {
 | |
| 		DPRINTF(("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
 | |
| 		    msginfo.msgmni));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	msqptr = &msqids[msqid];
 | |
| 	if (msqptr->msg_qbytes == 0) {
 | |
| 		DPRINTF(("no such message queue id\n"));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 	if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
 | |
| 		DPRINTF(("wrong sequence number\n"));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	if ((error = ipcperm(td, &msqptr->msg_perm, IPC_W))) {
 | |
| 		DPRINTF(("requester doesn't have write access\n"));
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	segs_needed = (msgsz + msginfo.msgssz - 1) / msginfo.msgssz;
 | |
| 	DPRINTF(("msgsz=%d, msgssz=%d, segs_needed=%d\n", msgsz, msginfo.msgssz,
 | |
| 	    segs_needed));
 | |
| 	for (;;) {
 | |
| 		int need_more_resources = 0;
 | |
| 
 | |
| 		/*
 | |
| 		 * check msgsz
 | |
| 		 * (inside this loop in case msg_qbytes changes while we sleep)
 | |
| 		 */
 | |
| 
 | |
| 		if (msgsz > msqptr->msg_qbytes) {
 | |
| 			DPRINTF(("msgsz > msqptr->msg_qbytes\n"));
 | |
| 			error = EINVAL;
 | |
| 			goto done2;
 | |
| 		}
 | |
| 
 | |
| 		if (msqptr->msg_perm.mode & MSG_LOCKED) {
 | |
| 			DPRINTF(("msqid is locked\n"));
 | |
| 			need_more_resources = 1;
 | |
| 		}
 | |
| 		if (msgsz + msqptr->msg_cbytes > msqptr->msg_qbytes) {
 | |
| 			DPRINTF(("msgsz + msg_cbytes > msg_qbytes\n"));
 | |
| 			need_more_resources = 1;
 | |
| 		}
 | |
| 		if (segs_needed > nfree_msgmaps) {
 | |
| 			DPRINTF(("segs_needed > nfree_msgmaps\n"));
 | |
| 			need_more_resources = 1;
 | |
| 		}
 | |
| 		if (free_msghdrs == NULL) {
 | |
| 			DPRINTF(("no more msghdrs\n"));
 | |
| 			need_more_resources = 1;
 | |
| 		}
 | |
| 
 | |
| 		if (need_more_resources) {
 | |
| 			int we_own_it;
 | |
| 
 | |
| 			if ((msgflg & IPC_NOWAIT) != 0) {
 | |
| 				DPRINTF(("need more resources but caller "
 | |
| 				    "doesn't want to wait\n"));
 | |
| 				error = EAGAIN;
 | |
| 				goto done2;
 | |
| 			}
 | |
| 
 | |
| 			if ((msqptr->msg_perm.mode & MSG_LOCKED) != 0) {
 | |
| 				DPRINTF(("we don't own the msqid_ds\n"));
 | |
| 				we_own_it = 0;
 | |
| 			} else {
 | |
| 				/* Force later arrivals to wait for our
 | |
| 				   request */
 | |
| 				DPRINTF(("we own the msqid_ds\n"));
 | |
| 				msqptr->msg_perm.mode |= MSG_LOCKED;
 | |
| 				we_own_it = 1;
 | |
| 			}
 | |
| 			DPRINTF(("goodnight\n"));
 | |
| 			error = msleep(msqptr, &msq_mtx, (PZERO - 4) | PCATCH,
 | |
| 			    "msgwait", 0);
 | |
| 			DPRINTF(("good morning, error=%d\n", error));
 | |
| 			if (we_own_it)
 | |
| 				msqptr->msg_perm.mode &= ~MSG_LOCKED;
 | |
| 			if (error != 0) {
 | |
| 				DPRINTF(("msgsnd:  interrupted system call\n"));
 | |
| #ifdef __CYGWIN__
 | |
| 			  if (error != EIDRM)
 | |
| #endif /* __CYGWIN__ */
 | |
| 				error = EINTR;
 | |
| 				goto done2;
 | |
| 			}
 | |
| 
 | |
| 			/*
 | |
| 			 * Make sure that the msq queue still exists
 | |
| 			 */
 | |
| 
 | |
| 			if (msqptr->msg_qbytes == 0) {
 | |
| 				DPRINTF(("msqid deleted\n"));
 | |
| 				error = EIDRM;
 | |
| 				goto done2;
 | |
| 			}
 | |
| 
 | |
| 		} else {
 | |
| 			DPRINTF(("got all the resources that we need\n"));
 | |
| 			break;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * We have the resources that we need.
 | |
| 	 * Make sure!
 | |
| 	 */
 | |
| 
 | |
| 	if (msqptr->msg_perm.mode & MSG_LOCKED)
 | |
| 		panic("msg_perm.mode & MSG_LOCKED");
 | |
| 	if (segs_needed > nfree_msgmaps)
 | |
| 		panic("segs_needed > nfree_msgmaps");
 | |
| 	if (msgsz + msqptr->msg_cbytes > msqptr->msg_qbytes)
 | |
| 		panic("msgsz + msg_cbytes > msg_qbytes");
 | |
| 	if (free_msghdrs == NULL)
 | |
| 		panic("no more msghdrs");
 | |
| 
 | |
| 	/*
 | |
| 	 * Re-lock the msqid_ds in case we page-fault when copying in the
 | |
| 	 * message
 | |
| 	 */
 | |
| 
 | |
| 	if ((msqptr->msg_perm.mode & MSG_LOCKED) != 0)
 | |
| 		panic("msqid_ds is already locked");
 | |
| 	msqptr->msg_perm.mode |= MSG_LOCKED;
 | |
| 
 | |
| 	/*
 | |
| 	 * Allocate a message header
 | |
| 	 */
 | |
| 
 | |
| 	msghdr = free_msghdrs;
 | |
| 	free_msghdrs = msghdr->msg_next;
 | |
| 	msghdr->msg_spot = -1;
 | |
| 	msghdr->msg_ts = msgsz;
 | |
| 
 | |
| 	/*
 | |
| 	 * Allocate space for the message
 | |
| 	 */
 | |
| 
 | |
| 	while (segs_needed > 0) {
 | |
| 		if (nfree_msgmaps <= 0)
 | |
| 			panic("not enough msgmaps");
 | |
| 		if (free_msgmaps == -1)
 | |
| 			panic("nil free_msgmaps");
 | |
| 		next = free_msgmaps;
 | |
| 		if (next <= -1)
 | |
| 			panic("next too low #1");
 | |
| 		if (next >= msginfo.msgseg)
 | |
| 			panic("next out of range #1");
 | |
| 		DPRINTF(("allocating segment %d to message\n", next));
 | |
| 		free_msgmaps = msgmaps[next].next;
 | |
| 		nfree_msgmaps--;
 | |
| 		msgmaps[next].next = msghdr->msg_spot;
 | |
| 		msghdr->msg_spot = next;
 | |
| 		segs_needed--;
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Copy in the message type
 | |
| 	 */
 | |
| 
 | |
| 	mtx_unlock(&msq_mtx);
 | |
| 	if ((error = copyin(user_msgp, &msghdr->msg_type,
 | |
| 	    sizeof(msghdr->msg_type))) != 0) {
 | |
| 		mtx_lock(&msq_mtx);
 | |
| 		DPRINTF(("error %d copying the message type\n", error));
 | |
| 		msg_freehdr(msghdr);
 | |
| 		msqptr->msg_perm.mode &= ~MSG_LOCKED;
 | |
| 		wakeup(msqptr);
 | |
| 		goto done2;
 | |
| 	}
 | |
| 	mtx_lock(&msq_mtx);
 | |
| 	user_msgp = (const char *)user_msgp + sizeof(msghdr->msg_type);
 | |
| 
 | |
| 	/*
 | |
| 	 * Validate the message type
 | |
| 	 */
 | |
| 
 | |
| 	if (msghdr->msg_type < 1) {
 | |
| 		msg_freehdr(msghdr);
 | |
| 		msqptr->msg_perm.mode &= ~MSG_LOCKED;
 | |
| 		wakeup(msqptr);
 | |
| 		DPRINTF(("mtype (%d) < 1\n", msghdr->msg_type));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Copy in the message body
 | |
| 	 */
 | |
| 
 | |
| 	next = msghdr->msg_spot;
 | |
| 	while (msgsz > 0) {
 | |
| 		size_t tlen;
 | |
| 		if (msgsz > (unsigned long) msginfo.msgssz)
 | |
| 			tlen = msginfo.msgssz;
 | |
| 		else
 | |
| 			tlen = msgsz;
 | |
| 		if (next <= -1)
 | |
| 			panic("next too low #2");
 | |
| 		if (next >= msginfo.msgseg)
 | |
| 			panic("next out of range #2");
 | |
| 		mtx_unlock(&msq_mtx);
 | |
| 		if ((error = copyin(user_msgp, &msgpool[next * msginfo.msgssz],
 | |
| 		    tlen)) != 0) {
 | |
| 			mtx_lock(&msq_mtx);
 | |
| 			DPRINTF(("error %d copying in message segment\n",
 | |
| 			    error));
 | |
| 			msg_freehdr(msghdr);
 | |
| 			msqptr->msg_perm.mode &= ~MSG_LOCKED;
 | |
| 			wakeup(msqptr);
 | |
| 			goto done2;
 | |
| 		}
 | |
| 		mtx_lock(&msq_mtx);
 | |
| 		msgsz -= tlen;
 | |
| 		user_msgp = (const char *)user_msgp + tlen;
 | |
| 		next = msgmaps[next].next;
 | |
| 	}
 | |
| 	if (next != -1)
 | |
| 		panic("didn't use all the msg segments");
 | |
| 
 | |
| 	/*
 | |
| 	 * We've got the message.  Unlock the msqid_ds.
 | |
| 	 */
 | |
| 
 | |
| 	msqptr->msg_perm.mode &= ~MSG_LOCKED;
 | |
| 
 | |
| 	/*
 | |
| 	 * Make sure that the msqid_ds is still allocated.
 | |
| 	 */
 | |
| 
 | |
| 	if (msqptr->msg_qbytes == 0) {
 | |
| 		msg_freehdr(msghdr);
 | |
| 		wakeup(msqptr);
 | |
| 		error = EIDRM;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Put the message into the queue
 | |
| 	 */
 | |
| 
 | |
| 	if (msqptr->msg_first == NULL) {
 | |
| 		msqptr->msg_first = msghdr;
 | |
| 		msqptr->msg_last = msghdr;
 | |
| 	} else {
 | |
| 		msqptr->msg_last->msg_next = msghdr;
 | |
| 		msqptr->msg_last = msghdr;
 | |
| 	}
 | |
| 	msqptr->msg_last->msg_next = NULL;
 | |
| 
 | |
| 	msqptr->msg_cbytes += msghdr->msg_ts;
 | |
| 	msqptr->msg_qnum++;
 | |
| 	msqptr->msg_lspid = td->td_proc->p_pid;
 | |
| 	msqptr->msg_stime = time (NULL);
 | |
| 
 | |
| #ifdef __CYGWIN__
 | |
| 	msg_info.msg_num++;
 | |
| 	msg_info.msg_tot += uap->msgsz;
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| 	wakeup(msqptr);
 | |
| 	td->td_retval[0] = 0;
 | |
| done2:
 | |
| 	mtx_unlock(&msq_mtx);
 | |
| 	return (error);
 | |
| }
 | |
| 
 | |
| #ifndef _SYS_SYSPROTO_H_
 | |
| struct msgrcv_args {
 | |
| 	int	msqid;
 | |
| 	void	*msgp;
 | |
| 	size_t	msgsz;
 | |
| 	long	msgtyp;
 | |
| 	int	msgflg;
 | |
| };
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * MPSAFE
 | |
|  */
 | |
| int
 | |
| msgrcv(struct thread *td, struct msgrcv_args *uap)
 | |
| {
 | |
| 	int msqid = uap->msqid;
 | |
| 	void *user_msgp = uap->msgp;
 | |
| 	size_t msgsz = uap->msgsz;
 | |
| 	long msgtyp = uap->msgtyp;
 | |
| 	int msgflg = uap->msgflg;
 | |
| 	size_t len;
 | |
| 	register struct msqid_ds *msqptr;
 | |
| 	register struct msg *msghdr;
 | |
| 	int error = 0;
 | |
| 	short next;
 | |
| 
 | |
| 	DPRINTF(("call to msgrcv(%d, 0x%x, %d, %ld, %d)\n", msqid, user_msgp,
 | |
| 	    msgsz, msgtyp, msgflg));
 | |
| 
 | |
| 	if (!jail_sysvipc_allowed && jailed(td->td_ucred))
 | |
| 		return (ENOSYS);
 | |
| 
 | |
| 	msqid = IPCID_TO_IX(msqid);
 | |
| 
 | |
| 	if (msqid < 0 || msqid >= msginfo.msgmni) {
 | |
| 		DPRINTF(("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
 | |
| 		    msginfo.msgmni));
 | |
| 		return (EINVAL);
 | |
| 	}
 | |
| 
 | |
| 	msqptr = &msqids[msqid];
 | |
| 	mtx_lock(&msq_mtx);
 | |
| 	if (msqptr->msg_qbytes == 0) {
 | |
| 		DPRINTF(("no such message queue id\n"));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 	if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
 | |
| 		DPRINTF(("wrong sequence number\n"));
 | |
| 		error = EINVAL;
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	if ((error = ipcperm(td, &msqptr->msg_perm, IPC_R))) {
 | |
| 		DPRINTF(("requester doesn't have read access\n"));
 | |
| 		goto done2;
 | |
| 	}
 | |
| 
 | |
| 	msghdr = NULL;
 | |
| 	while (msghdr == NULL) {
 | |
| 		if (msgtyp == 0) {
 | |
| 			msghdr = msqptr->msg_first;
 | |
| 			if (msghdr != NULL) {
 | |
| 				if (msgsz < msghdr->msg_ts &&
 | |
| 				    (msgflg & MSG_NOERROR) == 0) {
 | |
| 					DPRINTF(("first message on the queue "
 | |
| 					    "is too big (want %d, got %d)\n",
 | |
| 					    msgsz, msghdr->msg_ts));
 | |
| 					error = E2BIG;
 | |
| 					goto done2;
 | |
| 				}
 | |
| 				if (msqptr->msg_first == msqptr->msg_last) {
 | |
| 					msqptr->msg_first = NULL;
 | |
| 					msqptr->msg_last = NULL;
 | |
| 				} else {
 | |
| 					msqptr->msg_first = msghdr->msg_next;
 | |
| 					if (msqptr->msg_first == NULL)
 | |
| 						panic("msg_first/last screwed up #1");
 | |
| 				}
 | |
| 			}
 | |
| 		} else {
 | |
| 			struct msg *previous;
 | |
| 			struct msg **prev;
 | |
| 
 | |
| 			previous = NULL;
 | |
| 			prev = &(msqptr->msg_first);
 | |
| 			while ((msghdr = *prev) != NULL) {
 | |
| 				/*
 | |
| 				 * Is this message's type an exact match or is
 | |
| 				 * this message's type less than or equal to
 | |
| 				 * the absolute value of a negative msgtyp?
 | |
| 				 * Note that the second half of this test can
 | |
| 				 * NEVER be true if msgtyp is positive since
 | |
| 				 * msg_type is always positive!
 | |
| 				 */
 | |
| 
 | |
| 				if (msgtyp == msghdr->msg_type ||
 | |
| 				    msghdr->msg_type <= -msgtyp) {
 | |
| 					DPRINTF(("found message type %d, "
 | |
| 					    "requested %d\n",
 | |
| 					    msghdr->msg_type, msgtyp));
 | |
| 					if (msgsz < msghdr->msg_ts &&
 | |
| 					    (msgflg & MSG_NOERROR) == 0) {
 | |
| 						DPRINTF(("requested message "
 | |
| 						    "on the queue is too big "
 | |
| 						    "(want %d, got %d)\n",
 | |
| 						    msgsz, msghdr->msg_ts));
 | |
| 						error = E2BIG;
 | |
| 						goto done2;
 | |
| 					}
 | |
| 					*prev = msghdr->msg_next;
 | |
| 					if (msghdr == msqptr->msg_last) {
 | |
| 						if (previous == NULL) {
 | |
| 							if (prev !=
 | |
| 							    &msqptr->msg_first)
 | |
| 								panic("msg_first/last screwed up #2");
 | |
| 							msqptr->msg_first =
 | |
| 							    NULL;
 | |
| 							msqptr->msg_last =
 | |
| 							    NULL;
 | |
| 						} else {
 | |
| 							if (prev ==
 | |
| 							    &msqptr->msg_first)
 | |
| 								panic("msg_first/last screwed up #3");
 | |
| 							msqptr->msg_last =
 | |
| 							    previous;
 | |
| 						}
 | |
| 					}
 | |
| 					break;
 | |
| 				}
 | |
| 				previous = msghdr;
 | |
| 				prev = &(msghdr->msg_next);
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 		/*
 | |
| 		 * We've either extracted the msghdr for the appropriate
 | |
| 		 * message or there isn't one.
 | |
| 		 * If there is one then bail out of this loop.
 | |
| 		 */
 | |
| 
 | |
| 		if (msghdr != NULL)
 | |
| 			break;
 | |
| 
 | |
| 		/*
 | |
| 		 * Hmph!  No message found.  Does the user want to wait?
 | |
| 		 */
 | |
| 
 | |
| 		if ((msgflg & IPC_NOWAIT) != 0) {
 | |
| 			DPRINTF(("no appropriate message found (msgtyp=%d)\n",
 | |
| 			    msgtyp));
 | |
| 			/* The SVID says to return ENOMSG. */
 | |
| 			error = ENOMSG;
 | |
| 			goto done2;
 | |
| 		}
 | |
| 
 | |
| 		/*
 | |
| 		 * Wait for something to happen
 | |
| 		 */
 | |
| 
 | |
| 		DPRINTF(("msgrcv:  goodnight\n"));
 | |
| 		error = msleep(msqptr, &msq_mtx, (PZERO - 4) | PCATCH,
 | |
| 		    "msgwait", 0);
 | |
| 		DPRINTF(("msgrcv:  good morning (error=%d)\n", error));
 | |
| 
 | |
| 		if (error != 0) {
 | |
| 			DPRINTF(("msgsnd:  interrupted system call\n"));
 | |
| #ifdef __CYGWIN__
 | |
| 		    if (error != EIDRM)
 | |
| #endif /* __CYGWIN__ */
 | |
| 			error = EINTR;
 | |
| 			goto done2;
 | |
| 		}
 | |
| 
 | |
| 		/*
 | |
| 		 * Make sure that the msq queue still exists
 | |
| 		 */
 | |
| 
 | |
| 		if (msqptr->msg_qbytes == 0 ||
 | |
| 		    msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
 | |
| 			DPRINTF(("msqid deleted\n"));
 | |
| 			error = EIDRM;
 | |
| 			goto done2;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Return the message to the user.
 | |
| 	 *
 | |
| 	 * First, do the bookkeeping (before we risk being interrupted).
 | |
| 	 */
 | |
| 
 | |
| 	msqptr->msg_cbytes -= msghdr->msg_ts;
 | |
| 	msqptr->msg_qnum--;
 | |
| 	msqptr->msg_lrpid = td->td_proc->p_pid;
 | |
| 	msqptr->msg_rtime = time (NULL);
 | |
| 
 | |
| 	/*
 | |
| 	 * Make msgsz the actual amount that we'll be returning.
 | |
| 	 * Note that this effectively truncates the message if it is too long
 | |
| 	 * (since msgsz is never increased).
 | |
| 	 */
 | |
| 
 | |
| 	DPRINTF(("found a message, msgsz=%d, msg_ts=%d\n", msgsz,
 | |
| 	    msghdr->msg_ts));
 | |
| 	if (msgsz > msghdr->msg_ts)
 | |
| 		msgsz = msghdr->msg_ts;
 | |
| 
 | |
| 	/*
 | |
| 	 * Return the type to the user.
 | |
| 	 */
 | |
| 
 | |
| 	mtx_unlock(&msq_mtx);
 | |
| 	error = copyout(&(msghdr->msg_type), user_msgp,
 | |
| 	    sizeof(msghdr->msg_type));
 | |
| 	mtx_lock(&msq_mtx);
 | |
| 	if (error != 0) {
 | |
| 		DPRINTF(("error (%d) copying out message type\n", error));
 | |
| 		msg_freehdr(msghdr);
 | |
| 		wakeup(msqptr);
 | |
| 		goto done2;
 | |
| 	}
 | |
| 	user_msgp = (char *)user_msgp + sizeof(msghdr->msg_type);
 | |
| 
 | |
| 	/*
 | |
| 	 * Return the segments to the user
 | |
| 	 */
 | |
| 
 | |
| 	next = msghdr->msg_spot;
 | |
| 	for (len = 0; len < msgsz; len += msginfo.msgssz) {
 | |
| 		size_t tlen;
 | |
| 
 | |
| 		if (msgsz - len > (unsigned long) msginfo.msgssz)
 | |
| 			tlen = msginfo.msgssz;
 | |
| 		else
 | |
| 			tlen = msgsz - len;
 | |
| 		if (next <= -1)
 | |
| 			panic("next too low #3");
 | |
| 		if (next >= msginfo.msgseg)
 | |
| 			panic("next out of range #3");
 | |
| 		mtx_unlock(&msq_mtx);
 | |
| 		error = copyout(&msgpool[next * msginfo.msgssz],
 | |
| 		    user_msgp, tlen);
 | |
| 		mtx_lock(&msq_mtx);
 | |
| 		if (error != 0) {
 | |
| 			DPRINTF(("error (%d) copying out message segment\n",
 | |
| 			    error));
 | |
| 			msg_freehdr(msghdr);
 | |
| 			wakeup(msqptr);
 | |
| 			goto done2;
 | |
| 		}
 | |
| 		user_msgp = (char *)user_msgp + tlen;
 | |
| 		next = msgmaps[next].next;
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Done, return the actual number of bytes copied out.
 | |
| 	 */
 | |
| 
 | |
| #ifdef __CYGWIN__
 | |
| 	msg_info.msg_num--;
 | |
| 	msg_info.msg_tot -= msgsz;
 | |
| #endif /* __CYGWIN__ */
 | |
| 
 | |
| 	msg_freehdr(msghdr);
 | |
| 	wakeup(msqptr);
 | |
| 	td->td_retval[0] = msgsz;
 | |
| done2:
 | |
| 	mtx_unlock(&msq_mtx);
 | |
| 	return (error);
 | |
| }
 | |
| 
 | |
| #ifndef __CYGWIN__
 | |
| static int
 | |
| sysctl_msqids(SYSCTL_HANDLER_ARGS)
 | |
| {
 | |
| 
 | |
| 	return (SYSCTL_OUT(req, msqids,
 | |
| 	    sizeof(struct msqid_ds) * msginfo.msgmni));
 | |
| }
 | |
| 
 | |
| SYSCTL_DECL(_kern_ipc);
 | |
| SYSCTL_INT(_kern_ipc, OID_AUTO, msgmax, CTLFLAG_RD, &msginfo.msgmax, 0, "");
 | |
| SYSCTL_INT(_kern_ipc, OID_AUTO, msgmni, CTLFLAG_RDTUN, &msginfo.msgmni, 0, "");
 | |
| SYSCTL_INT(_kern_ipc, OID_AUTO, msgmnb, CTLFLAG_RD, &msginfo.msgmnb, 0, "");
 | |
| SYSCTL_INT(_kern_ipc, OID_AUTO, msgtql, CTLFLAG_RD, &msginfo.msgtql, 0, "");
 | |
| SYSCTL_INT(_kern_ipc, OID_AUTO, msgssz, CTLFLAG_RDTUN, &msginfo.msgssz, 0, "");
 | |
| SYSCTL_INT(_kern_ipc, OID_AUTO, msgseg, CTLFLAG_RDTUN, &msginfo.msgseg, 0, "");
 | |
| SYSCTL_PROC(_kern_ipc, OID_AUTO, msqids, CTLFLAG_RD,
 | |
|     NULL, 0, sysctl_msqids, "", "Message queue IDs");
 | |
| #endif /* __CYGWIN__ */
 | |
| #endif /* __OUTSIDE_CYGWIN__ */
 |