clnt_dg.c

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/*
 * Copyright (c) 2009, Sun Microsystems, Inc.
 * All rights reserved.
 *
 * 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 Sun Microsystems, 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. 
 */

/*
 * Implements a connectionless client side RPC.
 */
#include <wintirpc.h>
//#include <pthread.h>
#include <reentrant.h>
#include <sys/types.h>
//#include <sys/socket.h>
//#include <stdint.h>
//#include <sys/poll.h>

//#include <sys/time.h>

//#include <sys/ioctl.h>
#include <rpc/clnt.h>
//#include <arpa/inet.h>
#include <rpc/rpc.h>
#include <rpc/xdr.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
//#include <signal.h>
//#include <unistd.h>
//#include <err.h>
#include "rpc_com.h"

#ifdef IP_RECVERR
#include <asm/types.h>
#include <linux/errqueue.h>
#include <sys/uio.h>
#endif


#define MAX_DEFAULT_FDS                 20000

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, void *,
        xdrproc_t, void *, struct timeval);
static void clnt_dg_geterr(CLIENT *, struct rpc_err *);
static bool_t clnt_dg_freeres(CLIENT *, xdrproc_t, void *);
static void clnt_dg_abort(CLIENT *);
static bool_t clnt_dg_control(CLIENT *, u_int, void *);
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;
extern mutex_t clnt_fd_lock;
static cond_t   *dg_cv;
#ifndef _WIN32
#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
/* XXX Needs Windows signal/event stuff XXX */
#define release_fd_lock(fd, mask) {     \
    mutex_lock(&clnt_fd_lock);  \
    dg_fd_locks[WINSOCK_HANDLE_HASH(fd)] = 0;       \
    mutex_unlock(&clnt_fd_lock);    \
    \
    cond_signal(&dg_cv[WINSOCK_HANDLE_HASH(fd)]);   \
}
#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 {
    SOCKET              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 */
    int                 cu_async;
    int                 cu_connect; /* Use connect(). */
    int                 cu_connected;   /* Have done connect(). */
    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(fd, svcaddr, program, version, sendsz, recvsz)
    SOCKET 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 timeval now;
    struct rpc_msg call_msg;
#ifndef _WIN32
    sigset_t mask;
    sigset_t newmask;
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    struct __rpc_sockinfo si;
    u_long one = 1;

#ifndef _WIN32
    sigfillset(&newmask);
    thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    mutex_lock(&clnt_fd_lock);
    if (dg_fd_locks == (int *) NULL) {
        int cv_allocsz;
        size_t fd_allocsz;
        int dtbsize = __rpc_dtbsize();

        fd_allocsz = dtbsize * sizeof (int);
        dg_fd_locks = (int *) mem_alloc(fd_allocsz);
        if (dg_fd_locks == (int *) NULL) {
            mutex_unlock(&clnt_fd_lock);
//          thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
            goto err1;
        } else
            memset(dg_fd_locks, 0, fd_allocsz);

        cv_allocsz = dtbsize * sizeof (cond_t);
        dg_cv = (cond_t *) mem_alloc(cv_allocsz);
        if (dg_cv == (cond_t *) NULL) {
            mem_free(dg_fd_locks, fd_allocsz);
            dg_fd_locks = (int *) NULL;
            mutex_unlock(&clnt_fd_lock);
//          thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
            goto err1;
        } else {
            int i;

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

    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 = mem_alloc(sizeof (*cu) + sendsz + recvsz);
    if (cu == NULL)
        goto err1;
    (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() */
    cu->cu_wait.tv_sec = 15;    /* heuristically chosen */
    cu->cu_wait.tv_usec = 0;
    cu->cu_total.tv_sec = -1;
    cu->cu_total.tv_usec = -1;
    cu->cu_sendsz = sendsz;
    cu->cu_recvsz = recvsz;
    cu->cu_async = FALSE;
    cu->cu_connect = FALSE;
    cu->cu_connected = FALSE;
    (void) gettimeofday(&now, NULL);
//  call_msg.rm_xid = __RPC_GETXID(&now);

    call_msg.rm_xid = ((u_int32_t)_getpid() ^ (u_int32_t)(&now)->tv_sec ^ (u_int32_t)(&now)->tv_usec);
    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
#ifdef IP_RECVERR
    {
    int on = 1;
    setsockopt(fd, SOL_IP, IP_RECVERR, &on, sizeof(on));
    }
#endif
    ioctlsocket(fd, FIONBIO, &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;
    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);
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(cl, proc, xargs, argsp, xresults, resultsp, utimeout)
    CLIENT  *cl;            /* client handle */
    rpcproc_t   proc;       /* procedure number */
    xdrproc_t   xargs;      /* xdr routine for args */
    void        *argsp;     /* pointer to args */
    xdrproc_t   xresults;   /* xdr routine for results */
    void        *resultsp;  /* pointer to results */
    struct timeval  utimeout;   /* seconds to wait before giving up */
{
    struct cu_data *cu = (struct cu_data *)cl->cl_private;
    XDR *xdrs;
    size_t outlen = 0;
    struct rpc_msg reply_msg;
    XDR reply_xdrs;
    bool_t ok;
    int nrefreshes = 2;     /* number of times to refresh cred */
    struct timeval timeout;
        struct pollfd fd;
    int total_time, nextsend_time, tv=0;
    struct sockaddr *sa;
#ifndef _WIN32
    sigset_t mask;
    sigset_t newmask;
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    socklen_t inlen, salen;
    ssize_t recvlen = 0;
    int rpc_lock_value;
    u_int32_t xid, inval, outval;
#ifdef __REACTOS__
    fd_set infd;
#endif

    outlen = 0;
#ifndef _WIN32
    sigfillset(&newmask);
    thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
#else
        /* XXX Need Windows signal/event stuff here XXX */
#endif
    mutex_lock(&clnt_fd_lock);
    while (dg_fd_locks[WINSOCK_HANDLE_HASH(cu->cu_fd)])
        cond_wait(&dg_cv[WINSOCK_HANDLE_HASH(cu->cu_fd)], &clnt_fd_lock);
    rpc_lock_value = 1;
    dg_fd_locks[WINSOCK_HANDLE_HASH(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 */
    }
    total_time = timeout.tv_sec * 1000 + timeout.tv_usec / 1000;
    nextsend_time = cu->cu_wait.tv_sec * 1000 + cu->cu_wait.tv_usec / 1000;

    if (cu->cu_connect && !cu->cu_connected) {
        if (connect(cu->cu_fd, (struct sockaddr *)&cu->cu_raddr,
            cu->cu_rlen) < 0) {
            cu->cu_error.re_errno = errno;
            cu->cu_error.re_status = RPC_CANTSEND;
            goto out;
        }
        cu->cu_connected = 1;
    }
    if (cu->cu_connected) {
        sa = NULL;
        salen = 0;
    } else {
        sa = (struct sockaddr *)&cu->cu_raddr;
        salen = cu->cu_rlen;
    }

    /* Clean up in case the last call ended in a longjmp(3) call. */
call_again:
    xdrs = &(cu->cu_outxdrs);
    if (cu->cu_async == TRUE && xargs == NULL)
        goto get_reply;
    xdrs->x_op = XDR_ENCODE;
    XDR_SETPOS(xdrs, cu->cu_xdrpos);
    /*
     * the transaction is the first thing in the out buffer
     * XXX Yes, and it's in network byte order, so we should to
     * be careful when we increment it, shouldn't we.
     */
    xid = ntohl(*(u_int32_t *)(void *)(cu->cu_outbuf));
    xid++;
    *(u_int32_t *)(void *)(cu->cu_outbuf) = htonl(xid);

    if ((! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
        (! AUTH_MARSHALL(cl->cl_auth, xdrs, NULL)) ||
        (! (*xargs)(xdrs, argsp))) {
        cu->cu_error.re_status = RPC_CANTENCODEARGS;
        goto out;
    }
    outlen = (size_t)XDR_GETPOS(xdrs);

    /*
     * 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;
    }

send_again:
    if (total_time <= 0) {
        cu->cu_error.re_status = RPC_TIMEDOUT;
        goto out;
    }
    nextsend_time = cu->cu_wait.tv_sec * 1000 + cu->cu_wait.tv_usec / 1000;
    if (sendto(cu->cu_fd, cu->cu_outbuf, (int)outlen, 0, sa, salen) != outlen) {
        cu->cu_error.re_errno = errno;
        cu->cu_error.re_status = RPC_CANTSEND;
        goto out;
    }

get_reply:

    /*
     * 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;

        fd.fd = cu->cu_fd;
        fd.events = POLLIN;
        fd.revents = 0;
    while (total_time > 0) {
        tv = total_time < nextsend_time ? total_time : nextsend_time;
#ifndef __REACTOS__
                switch (poll(&fd, 1, tv)) {
#else
#ifdef IP_RECVERR
#error Not supported!
#endif
                /* ReactOS: use select instead of poll */
                FD_ZERO(&infd);
                FD_SET(cu->cu_fd, &infd);

                timeout.tv_sec = 0;
                timeout.tv_usec = tv * 1000;

                switch (select(0, &infd, NULL, NULL, &timeout)) {
#endif
                case 0:
                total_time -= tv;
                goto send_again;
                // XXX CHECK THIS FOR WINDOWS!
                case -1:
                        if (errno == EINTR)
                                continue;
                        cu->cu_error.re_status = RPC_CANTRECV;
                        cu->cu_error.re_errno = errno;
                        goto out;
                }
                break;
        }
#ifdef IP_RECVERR
      if (fd.revents & POLLERR)
    {
      struct msghdr msg;
      struct cmsghdr *cmsg;
      struct sock_extended_err *e;
      struct sockaddr_in err_addr;
      struct sockaddr_in *sin = (struct sockaddr_in *)&cu->cu_raddr;
      struct iovec iov;
      char *cbuf = (char *) alloca (outlen + 256);
      int ret;

      iov.iov_base = cbuf + 256;
      iov.iov_len = outlen;
      msg.msg_name = (void *) &err_addr;
      msg.msg_namelen = sizeof (err_addr);
      msg.msg_iov = &iov;
      msg.msg_iovlen = 1;
      msg.msg_flags = 0;
      msg.msg_control = cbuf;
      msg.msg_controllen = 256;
      ret = recvmsg (cu->cu_fd, &msg, MSG_ERRQUEUE);
      if (ret >= 0
          && memcmp (cbuf + 256, cu->cu_outbuf, ret) == 0
          && (msg.msg_flags & MSG_ERRQUEUE)
          && ((msg.msg_namelen == 0
           && ret >= 12)
          || (msg.msg_namelen == sizeof (err_addr)
              && err_addr.sin_family == AF_INET
              && memcmp (&err_addr.sin_addr, &sin->sin_addr,
                 sizeof (err_addr.sin_addr)) == 0
              && err_addr.sin_port == sin->sin_port)))
        for (cmsg = CMSG_FIRSTHDR (&msg); cmsg;
         cmsg = CMSG_NXTHDR (&msg, cmsg))
          if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR)
        {
          e = (struct sock_extended_err *) CMSG_DATA(cmsg);
          cu->cu_error.re_errno = e->ee_errno;
          release_fd_lock(cu->cu_fd, mask);
          return (cu->cu_error.re_status = RPC_CANTRECV);
        }
    }
#endif

    /* We have some data now */
    do {
        recvlen = recvfrom(cu->cu_fd, cu->cu_inbuf,
            cu->cu_recvsz, 0, NULL, NULL);
        errno = WSAGetLastError();
    } while (recvlen == SOCKET_ERROR && errno == WSAEINTR);
    if (recvlen == SOCKET_ERROR && errno != WSAEWOULDBLOCK) {
        cu->cu_error.re_errno = errno;
        cu->cu_error.re_status = RPC_CANTRECV;
        goto out;
    }

    if (recvlen < sizeof(u_int32_t)) {
        total_time -= tv;
        goto send_again;
    }

    if (cu->cu_async == TRUE)
        inlen = (socklen_t)recvlen;
    else {
        memcpy(&inval, cu->cu_inbuf, sizeof(u_int32_t));
        memcpy(&outval, cu->cu_outbuf, sizeof(u_int32_t));
        if (inval != outval) {
            total_time -= tv;
            goto send_again;
        }
        inlen = (socklen_t)recvlen;
    }

    /*
     * 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, 0)) {
                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, &reply_msg)) {
                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(cl, errp)
    CLIENT *cl;
    struct rpc_err *errp;
{
    struct cu_data *cu = (struct cu_data *)cl->cl_private;

    *errp = cu->cu_error;
}

static bool_t
clnt_dg_freeres(cl, xdr_res, res_ptr)
    CLIENT *cl;
    xdrproc_t xdr_res;
    void *res_ptr;
{
    struct cu_data *cu = (struct cu_data *)cl->cl_private;
    XDR *xdrs = &(cu->cu_outxdrs);
    bool_t dummy;
#ifndef _WIN32
    sigset_t mask;
    sigset_t newmask;

    sigfillset(&newmask);
    thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    mutex_lock(&clnt_fd_lock);
    while (dg_fd_locks[WINSOCK_HANDLE_HASH(cu->cu_fd)])
        cond_wait(&dg_cv[WINSOCK_HANDLE_HASH(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[WINSOCK_HANDLE_HASH(cu->cu_fd)]);
    return (dummy);
}

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

static bool_t
clnt_dg_control(cl, request, info)
    CLIENT *cl;
    u_int request;
    void *info;
{
    struct cu_data *cu = (struct cu_data *)cl->cl_private;
    struct netbuf *addr;
#ifndef _WIN32
    sigset_t mask;
    sigset_t newmask;
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    int rpc_lock_value;

#ifndef _WIN32
    sigfillset(&newmask);
    thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    mutex_lock(&clnt_fd_lock);
    while (dg_fd_locks[WINSOCK_HANDLE_HASH(cu->cu_fd)])
        cond_wait(&dg_cv[WINSOCK_HANDLE_HASH(cu->cu_fd)], &clnt_fd_lock);
    rpc_lock_value = 1;
    dg_fd_locks[WINSOCK_HANDLE_HASH(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 *)info)) {
            release_fd_lock(cu->cu_fd, mask);
            return (FALSE);
        }
        cu->cu_total = *(struct timeval *)info;
        break;
    case CLGET_TIMEOUT:
        *(struct timeval *)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 *)info)) {
            release_fd_lock(cu->cu_fd, mask);
            return (FALSE);
        }
        cu->cu_wait = *(struct timeval *)info;
        break;
    case CLGET_RETRY_TIMEOUT:
        *(struct timeval *)info = cu->cu_wait;
        break;
    case CLGET_FD:
        *(SOCKET *)info = cu->cu_fd;
        break;
    case CLGET_SVC_ADDR:
        addr = (struct netbuf *)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 *)info;
        if (addr->len < sizeof cu->cu_raddr) {
            release_fd_lock(cu->cu_fd, mask);
            return (FALSE);
        }
        (void) memcpy(&cu->cu_raddr, addr->buf, 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 *)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 *)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 *)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 *)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 *)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 *)info);
        break;
    case CLSET_ASYNC:
        cu->cu_async = *(int *)info;
        break;
    case CLSET_CONNECT:
        cu->cu_connect = *(int *)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(cl)
    CLIENT *cl;
{
    struct cu_data *cu = (struct cu_data *)cl->cl_private;
    SOCKET cu_fd = cu->cu_fd;
#ifndef _WIN32
    sigset_t mask;
    sigset_t newmask;

    sigfillset(&newmask);
    thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    mutex_lock(&clnt_fd_lock);
    while (dg_fd_locks[WINSOCK_HANDLE_HASH(cu_fd)])
        cond_wait(&dg_cv[WINSOCK_HANDLE_HASH(cu_fd)], &clnt_fd_lock);
    if (cu->cu_closeit)
        (void)closesocket(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[WINSOCK_HANDLE_HASH(cu_fd)]);
}

static struct clnt_ops *
clnt_dg_ops()
{
    static struct clnt_ops ops;
    extern mutex_t  ops_lock;
#ifndef _WIN32
    sigset_t mask;
    sigset_t newmask;

/* VARIABLES PROTECTED BY ops_lock: ops */

    sigfillset(&newmask);
    thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
#else
    /* XXX Need Windows signal/event stuff here XXX */
#endif
    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(t)
    struct timeval *t;
{
    return (t->tv_sec < -1 || t->tv_sec > 100000000 ||
        t->tv_usec < -1 || t->tv_usec > 1000000);
}