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File: [cvs.NetBSD.org] / src / lib / libc / rpc / clnt_dg.c (download)

Revision 1.29, Tue May 7 21:08:44 2013 UTC (10 years, 10 months ago) by christos
Branch: MAIN
CVS Tags: yamt-pagecache-base9, tls-maxphys-base, tls-earlyentropy-base, tls-earlyentropy, riastradh-xf86-video-intel-2-7-1-pre-2-21-15, riastradh-drm2-base3, riastradh-drm2-base2, riastradh-drm2-base1, riastradh-drm2-base, riastradh-drm2, prg-localcount2-base3, prg-localcount2-base2, prg-localcount2-base1, prg-localcount2-base, prg-localcount2, phil-wifi-base, phil-wifi-20200421, phil-wifi-20200411, phil-wifi-20200406, phil-wifi-20191119, phil-wifi-20190609, phil-wifi, pgoyette-localcount-base, pgoyette-localcount-20170426, pgoyette-localcount-20170320, pgoyette-localcount-20170107, pgoyette-localcount-20161104, pgoyette-localcount-20160806, pgoyette-localcount-20160726, pgoyette-localcount, pgoyette-compat-merge-20190127, pgoyette-compat-base, pgoyette-compat-20190127, pgoyette-compat-20190118, pgoyette-compat-1226, pgoyette-compat-1126, pgoyette-compat-1020, pgoyette-compat-0930, pgoyette-compat-0906, pgoyette-compat-0728, pgoyette-compat-0625, pgoyette-compat-0521, pgoyette-compat-0502, pgoyette-compat-0422, pgoyette-compat-0415, pgoyette-compat-0407, pgoyette-compat-0330, pgoyette-compat-0322, pgoyette-compat-0315, pgoyette-compat, perseant-stdc-iso10646-base, perseant-stdc-iso10646, netbsd-9-base, netbsd-9-3-RELEASE, netbsd-9-2-RELEASE, netbsd-9-1-RELEASE, netbsd-9-0-RELEASE, netbsd-9-0-RC2, netbsd-9-0-RC1, netbsd-9, netbsd-8-base, netbsd-8-2-RELEASE, netbsd-8-1-RELEASE, netbsd-8-1-RC1, netbsd-8-0-RELEASE, netbsd-8-0-RC2, netbsd-8-0-RC1, netbsd-8, netbsd-7-nhusb-base-20170116, netbsd-7-nhusb-base, netbsd-7-nhusb, netbsd-7-base, netbsd-7-2-RELEASE, netbsd-7-1-RELEASE, netbsd-7-1-RC2, netbsd-7-1-RC1, netbsd-7-1-2-RELEASE, netbsd-7-1-1-RELEASE, netbsd-7-1, netbsd-7-0-RELEASE, netbsd-7-0-RC3, netbsd-7-0-RC2, netbsd-7-0-RC1, netbsd-7-0-2-RELEASE, netbsd-7-0-1-RELEASE, netbsd-7-0, netbsd-7, matt-nb8-mediatek-base, matt-nb8-mediatek, localcount-20160914, is-mlppp-base, is-mlppp, cjep_sun2x-base1, cjep_sun2x-base, cjep_sun2x, cjep_staticlib_x-base1, cjep_staticlib_x-base, cjep_staticlib_x, bouyer-socketcan-base1, bouyer-socketcan-base, bouyer-socketcan
Changes since 1.28: +13 -14 lines

- add __clnt_sigfillset() that does not blindly block all signals but excludes
  the tty generated ones (int, quit, tstp), plus term and hup. This makes
  command line clients behave on connect(2) where before they would need
  to be killed from a different tty. Much easier than making the file
  descriptor non-blocking for the duration of connect and then using
  pselect/pollts to detect when actual connection or timeout occured using
  a different sigmask.
- factor out some of the error paths.

/*	$NetBSD: clnt_dg.c,v 1.29 2013/05/07 21:08:44 christos Exp $	*/

/*
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of the "Oracle America, Inc." nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   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.
 */
/*
 * Copyright (c) 1986-1991 by Sun Microsystems Inc. 
 */

/* #ident	"@(#)clnt_dg.c	1.23	94/04/22 SMI" */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)clnt_dg.c 1.19 89/03/16 Copyr 1988 Sun Micro";
#else
__RCSID("$NetBSD: clnt_dg.c,v 1.29 2013/05/07 21:08:44 christos Exp $");
#endif
#endif

/*
 * Implements a connectionless client side RPC.
 */

#include "namespace.h"
#include "reentrant.h"
#include <sys/poll.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <rpc/rpc.h>
#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <err.h>

#include "svc_fdset.h"
#include "rpc_internal.h"

#ifdef __weak_alias
__weak_alias(clnt_dg_create,_clnt_dg_create)
#endif

#define	RPC_MAX_BACKOFF		30 /* seconds */


static struct clnt_ops *clnt_dg_ops(void);
static bool_t time_not_ok(struct timeval *);
static enum clnt_stat clnt_dg_call(CLIENT *, rpcproc_t, xdrproc_t,
    const char *, xdrproc_t, caddr_t, struct timeval);
static void clnt_dg_geterr(CLIENT *, struct rpc_err *);
static bool_t clnt_dg_freeres(CLIENT *, xdrproc_t, caddr_t);
static void clnt_dg_abort(CLIENT *);
static bool_t clnt_dg_control(CLIENT *, u_int, char *);
static void clnt_dg_destroy(CLIENT *);




/*
 *	This machinery implements per-fd locks for MT-safety.  It is not
 *	sufficient to do per-CLIENT handle locks for MT-safety because a
 *	user may create more than one CLIENT handle with the same fd behind
 *	it.  Therfore, we allocate an array of flags (dg_fd_locks), protected
 *	by the clnt_fd_lock mutex, and an array (dg_cv) of condition variables
 *	similarly protected.  Dg_fd_lock[fd] == 1 => a call is activte on some
 *	CLIENT handle created for that fd.
 *	The current implementation holds locks across the entire RPC and reply,
 *	including retransmissions.  Yes, this is silly, and as soon as this
 *	code is proven to work, this should be the first thing fixed.  One step
 *	at a time.
 */
static int	*dg_fd_locks;
#ifdef _REENTRANT
#define __rpc_lock_value __isthreaded;
extern mutex_t clnt_fd_lock;
static cond_t	*dg_cv;
#define	release_fd_lock(fd, mask) {		\
	mutex_lock(&clnt_fd_lock);	\
	dg_fd_locks[fd] = 0;		\
	mutex_unlock(&clnt_fd_lock);	\
	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);	\
	cond_signal(&dg_cv[fd]);	\
}
#else
#define release_fd_lock(fd,mask)
#define __rpc_lock_value 0
#endif

static const char mem_err_clnt_dg[] = "clnt_dg_create: out of memory";

/* VARIABLES PROTECTED BY clnt_fd_lock: dg_fd_locks, dg_cv */

/*
 * Private data kept per client handle
 */
struct cu_data {
	int			cu_fd;		/* connections fd */
	bool_t			cu_closeit;	/* opened by library */
	struct sockaddr_storage	cu_raddr;	/* remote address */
	int			cu_rlen;
	struct timeval		cu_wait;	/* retransmit interval */
	struct timeval		cu_total;	/* total time for the call */
	struct rpc_err		cu_error;
	XDR			cu_outxdrs;
	u_int			cu_xdrpos;
	u_int			cu_sendsz;	/* send size */
	char			*cu_outbuf;
	u_int			cu_recvsz;	/* recv size */
	struct pollfd		cu_pfdp;
	char			cu_inbuf[1];
};

/*
 * Connection less client creation returns with client handle parameters.
 * Default options are set, which the user can change using clnt_control().
 * fd should be open and bound.
 * NB: The rpch->cl_auth is initialized to null authentication.
 * 	Caller may wish to set this something more useful.
 *
 * sendsz and recvsz are the maximum allowable packet sizes that can be
 * sent and received. Normally they are the same, but they can be
 * changed to improve the program efficiency and buffer allocation.
 * If they are 0, use the transport default.
 *
 * If svcaddr is NULL, returns NULL.
 */
CLIENT *
clnt_dg_create(
	int fd,				/* open file descriptor */
	const struct netbuf *svcaddr,	/* servers address */
	rpcprog_t program,		/* program number */
	rpcvers_t version,		/* version number */
	u_int sendsz,			/* buffer recv size */
	u_int recvsz)			/* buffer send size */
{
	CLIENT *cl = NULL;		/* client handle */
	struct cu_data *cu = NULL;	/* private data */
	struct rpc_msg call_msg;
#ifdef _REENTRANT
	sigset_t mask;
#endif
	sigset_t newmask;
	struct __rpc_sockinfo si;
	int one = 1;

	__clnt_sigfillset(&newmask);
	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
	mutex_lock(&clnt_fd_lock);
	if (dg_fd_locks == NULL) {
#ifdef _REENTRANT
		size_t cv_allocsz;
#endif
		size_t fd_allocsz;
		int dtbsize = __rpc_dtbsize();

		fd_allocsz = dtbsize * sizeof (int);
		dg_fd_locks = mem_alloc(fd_allocsz);
		if (dg_fd_locks == NULL) {
			goto err0;
		} else
			memset(dg_fd_locks, '\0', fd_allocsz);

#ifdef _REENTRANT
		cv_allocsz = dtbsize * sizeof (cond_t);
		dg_cv = mem_alloc(cv_allocsz);
		if (dg_cv == NULL) {
			mem_free(dg_fd_locks, fd_allocsz);
			dg_fd_locks = NULL;
			goto err0;
		} else {
			int i;

			for (i = 0; i < dtbsize; i++)
				cond_init(&dg_cv[i], 0, (void *) 0);
		}
#endif
	}

	mutex_unlock(&clnt_fd_lock);
	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);

	if (svcaddr == NULL) {
		rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
		return (NULL);
	}

	if (!__rpc_fd2sockinfo(fd, &si)) {
		rpc_createerr.cf_stat = RPC_TLIERROR;
		rpc_createerr.cf_error.re_errno = 0;
		return (NULL);
	}
	/*
	 * Find the receive and the send size
	 */
	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
	recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
	if ((sendsz == 0) || (recvsz == 0)) {
		rpc_createerr.cf_stat = RPC_TLIERROR; /* XXX */
		rpc_createerr.cf_error.re_errno = 0;
		return (NULL);
	}

	if ((cl = mem_alloc(sizeof (CLIENT))) == NULL)
		goto err1;
	/*
	 * Should be multiple of 4 for XDR.
	 */
	sendsz = ((sendsz + 3) / 4) * 4;
	recvsz = ((recvsz + 3) / 4) * 4;
	cu = malloc(sizeof (*cu) + sendsz + recvsz);
	if (cu == NULL)
		goto err1;
	memset(cu, 0, sizeof(*cu));
	(void) memcpy(&cu->cu_raddr, svcaddr->buf, (size_t)svcaddr->len);
	cu->cu_rlen = svcaddr->len;
	cu->cu_outbuf = &cu->cu_inbuf[recvsz];
	/* Other values can also be set through clnt_control() */
#ifdef RUMP_RPC
	cu->cu_wait.tv_sec = 15;	/* heuristically chosen */
	cu->cu_wait.tv_usec = 0;
#else
	cu->cu_wait.tv_sec = 0;		/* for testing, 10x / second */
	cu->cu_wait.tv_usec = 100000;
#endif
	cu->cu_total.tv_sec = -1;
	cu->cu_total.tv_usec = -1;
	cu->cu_sendsz = sendsz;
	cu->cu_recvsz = recvsz;
	call_msg.rm_xid = __RPC_GETXID();
	call_msg.rm_call.cb_prog = program;
	call_msg.rm_call.cb_vers = version;
	xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf, sendsz, XDR_ENCODE);
	if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
		rpc_createerr.cf_stat = RPC_CANTENCODEARGS;  /* XXX */
		rpc_createerr.cf_error.re_errno = 0;
		goto err2;
	}
	cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));

	/* XXX fvdl - do we still want this? */
#if 0
	(void)bindresvport_sa(fd, (struct sockaddr *)svcaddr->buf);
#endif
	ioctl(fd, FIONBIO, (char *)(void *)&one);

	/*
	 * By default, closeit is always FALSE. It is users responsibility
	 * to do a close on it, else the user may use clnt_control
	 * to let clnt_destroy do it for him/her.
	 */
	cu->cu_closeit = FALSE;
	cu->cu_fd = fd;
	cu->cu_pfdp.fd = cu->cu_fd;
	cu->cu_pfdp.events = POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND;
	cl->cl_ops = clnt_dg_ops();
	cl->cl_private = (caddr_t)(void *)cu;
	cl->cl_auth = authnone_create();
	cl->cl_tp = NULL;
	cl->cl_netid = NULL;
	return (cl);
err0:
	mutex_unlock(&clnt_fd_lock);
	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
err1:
	warnx(mem_err_clnt_dg);
	rpc_createerr.cf_stat = RPC_SYSTEMERROR;
	rpc_createerr.cf_error.re_errno = errno;
err2:
	if (cl) {
		mem_free(cl, sizeof (CLIENT));
		if (cu)
			mem_free(cu, sizeof (*cu) + sendsz + recvsz);
	}
	return (NULL);
}

static enum clnt_stat
clnt_dg_call(
	CLIENT *	cl,		/* client handle */
	rpcproc_t	proc,		/* procedure number */
	xdrproc_t	xargs,		/* xdr routine for args */
	const char *	argsp,		/* pointer to args */
	xdrproc_t	xresults,	/* xdr routine for results */
	caddr_t		resultsp,	/* pointer to results */
	struct timeval	utimeout)	/* seconds to wait before giving up */
{
	struct cu_data *cu;
	XDR *xdrs;
	size_t outlen;
	struct rpc_msg reply_msg;
	XDR reply_xdrs;
	bool_t ok;
	int nrefreshes = 2;		/* number of times to refresh cred */
	struct timeval timeout;
	struct timeval retransmit_time;
	struct timeval next_sendtime, starttime, time_waited, tv;
#ifdef _REENTRANT
	sigset_t mask, *maskp = &mask;
#else
	sigset_t *maskp = NULL;
#endif
	sigset_t newmask;
	ssize_t recvlen = 0;
	struct timespec ts;
	int n;

	_DIAGASSERT(cl != NULL);

	cu = (struct cu_data *)cl->cl_private;

	__clnt_sigfillset(&newmask);
	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
	mutex_lock(&clnt_fd_lock);
	while (dg_fd_locks[cu->cu_fd])
		cond_wait(&dg_cv[cu->cu_fd], &clnt_fd_lock);
	dg_fd_locks[cu->cu_fd] = __rpc_lock_value;
	mutex_unlock(&clnt_fd_lock);
	if (cu->cu_total.tv_usec == -1) {
		timeout = utimeout;	/* use supplied timeout */
	} else {
		timeout = cu->cu_total;	/* use default timeout */
	}

	time_waited.tv_sec = 0;
	time_waited.tv_usec = 0;
	retransmit_time = next_sendtime = cu->cu_wait;
	gettimeofday(&starttime, NULL);

call_again:
	xdrs = &(cu->cu_outxdrs);
	xdrs->x_op = XDR_ENCODE;
	XDR_SETPOS(xdrs, cu->cu_xdrpos);
	/*
	 * the transaction is the first thing in the out buffer
	 */
	(*(u_int32_t *)(void *)(cu->cu_outbuf))++;
	if ((! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
	    (! AUTH_MARSHALL(cl->cl_auth, xdrs)) ||
	    (! (*xargs)(xdrs, __UNCONST(argsp)))) {
		cu->cu_error.re_status = RPC_CANTENCODEARGS;
		goto out;
	}
	outlen = (size_t)XDR_GETPOS(xdrs);

send_again:
	if ((size_t)sendto(cu->cu_fd, cu->cu_outbuf, outlen, 0,
	    (struct sockaddr *)(void *)&cu->cu_raddr, (socklen_t)cu->cu_rlen)
	    != outlen) {
		cu->cu_error.re_errno = errno;
		cu->cu_error.re_status = RPC_CANTSEND;
		goto out;
	}

	/*
	 * Hack to provide rpc-based message passing
	 */
	if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
		cu->cu_error.re_status = RPC_TIMEDOUT;
		goto out;
	}
	/*
	 * sub-optimal code appears here because we have
	 * some clock time to spare while the packets are in flight.
	 * (We assume that this is actually only executed once.)
	 */
	reply_msg.acpted_rply.ar_verf = _null_auth;
	reply_msg.acpted_rply.ar_results.where = resultsp;
	reply_msg.acpted_rply.ar_results.proc = xresults;


	for (;;) {
		/* Decide how long to wait. */
		if (timercmp(&next_sendtime, &timeout, <))
			timersub(&next_sendtime, &time_waited, &tv);
		else
			timersub(&timeout, &time_waited, &tv);
		if (tv.tv_sec < 0 || tv.tv_usec < 0)
			tv.tv_sec = tv.tv_usec = 0;
		TIMEVAL_TO_TIMESPEC(&tv, &ts);

		n = pollts(&cu->cu_pfdp, 1, &ts, maskp);
		if (n == 1) {
			/* We have some data now */
			do {
				recvlen = recvfrom(cu->cu_fd, cu->cu_inbuf,
				    cu->cu_recvsz, 0, NULL, NULL);
			} while (recvlen < 0 && errno == EINTR);
			
			if (recvlen < 0 && errno != EWOULDBLOCK) {
				cu->cu_error.re_errno = errno;
				cu->cu_error.re_status = RPC_CANTRECV;
				goto out;
			}
			if (recvlen >= (ssize_t)sizeof(uint32_t)) {
				if (memcmp(cu->cu_inbuf, cu->cu_outbuf,
				    sizeof(uint32_t)) == 0)
					/* Assume we have the proper reply. */
					break;
			}
		}
		if (n == -1) {
			cu->cu_error.re_errno = errno;
			cu->cu_error.re_status = RPC_CANTRECV;
			goto out;
		}

		gettimeofday(&tv, NULL);
		timersub(&tv, &starttime, &time_waited);

		/* Check for timeout. */
		if (timercmp(&time_waited, &timeout, >)) {
			cu->cu_error.re_status = RPC_TIMEDOUT;
			goto out;
		}

		/* Retransmit if necessary. */
		if (timercmp(&time_waited, &next_sendtime, >)) {
			/* update retransmit_time */
			if (retransmit_time.tv_sec < RPC_MAX_BACKOFF)
				timeradd(&retransmit_time, &retransmit_time,
				    &retransmit_time);
			timeradd(&next_sendtime, &retransmit_time,
			    &next_sendtime);
			goto send_again;
		}
	}

	/*
	 * now decode and validate the response
	 */

	xdrmem_create(&reply_xdrs, cu->cu_inbuf, (u_int)recvlen, XDR_DECODE);
	ok = xdr_replymsg(&reply_xdrs, &reply_msg);
	/* XDR_DESTROY(&reply_xdrs);	save a few cycles on noop destroy */
	if (ok) {
		if ((reply_msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
			(reply_msg.acpted_rply.ar_stat == SUCCESS))
			cu->cu_error.re_status = RPC_SUCCESS;
		else
			_seterr_reply(&reply_msg, &(cu->cu_error));

		if (cu->cu_error.re_status == RPC_SUCCESS) {
			if (! AUTH_VALIDATE(cl->cl_auth,
					    &reply_msg.acpted_rply.ar_verf)) {
				cu->cu_error.re_status = RPC_AUTHERROR;
				cu->cu_error.re_why = AUTH_INVALIDRESP;
			}
			if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
				xdrs->x_op = XDR_FREE;
				(void) xdr_opaque_auth(xdrs,
					&(reply_msg.acpted_rply.ar_verf));
			}
		}		/* end successful completion */
		/*
		 * If unsuccesful AND error is an authentication error
		 * then refresh credentials and try again, else break
		 */
		else if (cu->cu_error.re_status == RPC_AUTHERROR)
			/* maybe our credentials need to be refreshed ... */
			if (nrefreshes > 0 && AUTH_REFRESH(cl->cl_auth)) {
				nrefreshes--;
				goto call_again;
			}
		/* end of unsuccessful completion */
	}	/* end of valid reply message */
	else {
		cu->cu_error.re_status = RPC_CANTDECODERES;

	}
out:
	release_fd_lock(cu->cu_fd, mask);
	return (cu->cu_error.re_status);
}

static void
clnt_dg_geterr(CLIENT *cl, struct rpc_err *errp)
{
	struct cu_data *cu;

	_DIAGASSERT(cl != NULL);
	_DIAGASSERT(errp != NULL);

	cu = (struct cu_data *)cl->cl_private;
	*errp = cu->cu_error;
}

static bool_t
clnt_dg_freeres(CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
{
	struct cu_data *cu;
	XDR *xdrs;
	bool_t dummy;
#ifdef _REENTRANT
	sigset_t mask;
#endif
	sigset_t newmask;

	_DIAGASSERT(cl != NULL);
	cu = (struct cu_data *)cl->cl_private;
	xdrs = &(cu->cu_outxdrs);

	__clnt_sigfillset(&newmask);
	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
	mutex_lock(&clnt_fd_lock);
	while (dg_fd_locks[cu->cu_fd])
		cond_wait(&dg_cv[cu->cu_fd], &clnt_fd_lock);
	xdrs->x_op = XDR_FREE;
	dummy = (*xdr_res)(xdrs, res_ptr);
	mutex_unlock(&clnt_fd_lock);
	thr_sigsetmask(SIG_SETMASK, &mask, NULL);
	cond_signal(&dg_cv[cu->cu_fd]);
	return (dummy);
}

/*ARGSUSED*/
static void
clnt_dg_abort(CLIENT *h)
{
}

static bool_t
clnt_dg_control(CLIENT *cl, u_int request, char *info)
{
	struct cu_data *cu;
	struct netbuf *addr;
#ifdef _REENTRANT
	sigset_t mask;
#endif
	sigset_t newmask;

	_DIAGASSERT(cl != NULL);
	/* info is handled below */

	cu = (struct cu_data *)cl->cl_private;

	__clnt_sigfillset(&newmask);
	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
	mutex_lock(&clnt_fd_lock);
	while (dg_fd_locks[cu->cu_fd])
		cond_wait(&dg_cv[cu->cu_fd], &clnt_fd_lock);
	dg_fd_locks[cu->cu_fd] = __rpc_lock_value;
	mutex_unlock(&clnt_fd_lock);
	switch (request) {
	case CLSET_FD_CLOSE:
		cu->cu_closeit = TRUE;
		release_fd_lock(cu->cu_fd, mask);
		return (TRUE);
	case CLSET_FD_NCLOSE:
		cu->cu_closeit = FALSE;
		release_fd_lock(cu->cu_fd, mask);
		return (TRUE);
	}

	/* for other requests which use info */
	if (info == NULL) {
		release_fd_lock(cu->cu_fd, mask);
		return (FALSE);
	}
	switch (request) {
	case CLSET_TIMEOUT:
		if (time_not_ok((struct timeval *)(void *)info)) {
			release_fd_lock(cu->cu_fd, mask);
			return (FALSE);
		}
		cu->cu_total = *(struct timeval *)(void *)info;
		break;
	case CLGET_TIMEOUT:
		*(struct timeval *)(void *)info = cu->cu_total;
		break;
	case CLGET_SERVER_ADDR:		/* Give him the fd address */
		/* Now obsolete. Only for backward compatibility */
		(void) memcpy(info, &cu->cu_raddr, (size_t)cu->cu_rlen);
		break;
	case CLSET_RETRY_TIMEOUT:
		if (time_not_ok((struct timeval *)(void *)info)) {
			release_fd_lock(cu->cu_fd, mask);
			return (FALSE);
		}
		cu->cu_wait = *(struct timeval *)(void *)info;
		break;
	case CLGET_RETRY_TIMEOUT:
		*(struct timeval *)(void *)info = cu->cu_wait;
		break;
	case CLGET_FD:
		*(int *)(void *)info = cu->cu_fd;
		break;
	case CLGET_SVC_ADDR:
		addr = (struct netbuf *)(void *)info;
		addr->buf = &cu->cu_raddr;
		addr->len = cu->cu_rlen;
		addr->maxlen = sizeof cu->cu_raddr;
		break;
	case CLSET_SVC_ADDR:		/* set to new address */
		addr = (struct netbuf *)(void *)info;
		if (addr->len < sizeof cu->cu_raddr) {
			release_fd_lock(cu->cu_fd, mask);
			return (FALSE);
		}
		(void) memcpy(&cu->cu_raddr, addr->buf, (size_t)addr->len);
		cu->cu_rlen = addr->len;
		break;
	case CLGET_XID:
		/*
		 * use the knowledge that xid is the
		 * first element in the call structure *.
		 * This will get the xid of the PREVIOUS call
		 */
		*(u_int32_t *)(void *)info =
		    ntohl(*(u_int32_t *)(void *)cu->cu_outbuf);
		break;

	case CLSET_XID:
		/* This will set the xid of the NEXT call */
		*(u_int32_t *)(void *)cu->cu_outbuf =
		    htonl(*(u_int32_t *)(void *)info - 1);
		/* decrement by 1 as clnt_dg_call() increments once */
		break;

	case CLGET_VERS:
		/*
		 * This RELIES on the information that, in the call body,
		 * the version number field is the fifth field from the
		 * begining of the RPC header. MUST be changed if the
		 * call_struct is changed
		 */
		*(u_int32_t *)(void *)info =
		    ntohl(*(u_int32_t *)(void *)(cu->cu_outbuf +
		    4 * BYTES_PER_XDR_UNIT));
		break;

	case CLSET_VERS:
		*(u_int32_t *)(void *)(cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT)
			= htonl(*(u_int32_t *)(void *)info);
		break;

	case CLGET_PROG:
		/*
		 * This RELIES on the information that, in the call body,
		 * the program number field is the fourth field from the
		 * begining of the RPC header. MUST be changed if the
		 * call_struct is changed
		 */
		*(u_int32_t *)(void *)info =
		    ntohl(*(u_int32_t *)(void *)(cu->cu_outbuf +
		    3 * BYTES_PER_XDR_UNIT));
		break;

	case CLSET_PROG:
		*(u_int32_t *)(void *)(cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT)
			= htonl(*(u_int32_t *)(void *)info);
		break;

	default:
		release_fd_lock(cu->cu_fd, mask);
		return (FALSE);
	}
	release_fd_lock(cu->cu_fd, mask);
	return (TRUE);
}

static void
clnt_dg_destroy(CLIENT *cl)
{
	struct cu_data *cu;
	int cu_fd;
#ifdef _REENTRANT
	sigset_t mask;
#endif
	sigset_t newmask;

	_DIAGASSERT(cl != NULL);

	cu = (struct cu_data *)cl->cl_private;
	cu_fd = cu->cu_fd;

	__clnt_sigfillset(&newmask);
	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
	mutex_lock(&clnt_fd_lock);
	while (dg_fd_locks[cu_fd])
		cond_wait(&dg_cv[cu_fd], &clnt_fd_lock);
	if (cu->cu_closeit)
		(void) close(cu_fd);
	XDR_DESTROY(&(cu->cu_outxdrs));
	mem_free(cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
	if (cl->cl_netid && cl->cl_netid[0])
		mem_free(cl->cl_netid, strlen(cl->cl_netid) +1);
	if (cl->cl_tp && cl->cl_tp[0])
		mem_free(cl->cl_tp, strlen(cl->cl_tp) +1);
	mem_free(cl, sizeof (CLIENT));
	mutex_unlock(&clnt_fd_lock);
	thr_sigsetmask(SIG_SETMASK, &mask, NULL);
	cond_signal(&dg_cv[cu_fd]);
}

static struct clnt_ops *
clnt_dg_ops(void)
{
	static struct clnt_ops ops;
#ifdef _REENTRANT
	extern mutex_t	ops_lock;
	sigset_t mask;
#endif
	sigset_t newmask;

/* VARIABLES PROTECTED BY ops_lock: ops */

	__clnt_sigfillset(&newmask);
	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
	mutex_lock(&ops_lock);
	if (ops.cl_call == NULL) {
		ops.cl_call = clnt_dg_call;
		ops.cl_abort = clnt_dg_abort;
		ops.cl_geterr = clnt_dg_geterr;
		ops.cl_freeres = clnt_dg_freeres;
		ops.cl_destroy = clnt_dg_destroy;
		ops.cl_control = clnt_dg_control;
	}
	mutex_unlock(&ops_lock);
	thr_sigsetmask(SIG_SETMASK, &mask, NULL);
	return (&ops);
}

/*
 * Make sure that the time is not garbage.  -1 value is allowed.
 */
static bool_t
time_not_ok(struct timeval *t)
{

	_DIAGASSERT(t != NULL);

	return (t->tv_sec < -1 || t->tv_sec > 100000000 ||
		t->tv_usec < -1 || t->tv_usec > 1000000);
}