source: rtems/cpukit/libnetworking/kern/uipc_socket.c @ f87ede5

/*
 * Copyright (c) 1982, 1986, 1988, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 *
 *      @(#)uipc_socket.c       8.3 (Berkeley) 4/15/94
 */

#include <sys/param.h>
#include <sys/queue.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/sysctl.h>
#include <limits.h>

static int somaxconn = SOMAXCONN;
SYSCTL_INT(_kern, KIPC_SOMAXCONN, somaxconn, CTLFLAG_RW, &somaxconn, 0, "");

/*
 * Socket operation routines.
 * These routines are called by the routines in
 * sys_socket.c or from a system process, and
 * implement the semantics of socket operations by
 * switching out to the protocol specific routines.
 */
/*ARGSUSED*/
int
socreate(int dom, struct socket **aso, int type, int proto,
    struct proc *p)
{
        register struct protosw *prp;
        register struct socket *so;
        register int error;

        if (proto)
                prp = pffindproto(dom, proto, type);
        else
                prp = pffindtype(dom, type);
        if (prp == 0 || prp->pr_usrreqs == 0)
                return (EPROTONOSUPPORT);
        if (prp->pr_type != type)
                return (EPROTOTYPE);
        MALLOC(so, struct socket *, sizeof(*so), M_SOCKET, M_WAIT);
        bzero((caddr_t)so, sizeof(*so));
        TAILQ_INIT(&so->so_incomp);
        TAILQ_INIT(&so->so_comp);
        so->so_type = type;
        so->so_state = SS_PRIV;
        so->so_proto = prp;
        error = (*prp->pr_usrreqs->pru_attach)(so, proto);
        if (error) {
                so->so_state |= SS_NOFDREF;
                sofree(so);
                return (error);
        }
        *aso = so;
        return (0);
}

int
sobind(struct socket *so, struct mbuf *nam)
{
        int s = splnet();
        int error;

        error = (*so->so_proto->pr_usrreqs->pru_bind)(so, nam);
        splx(s);
        return (error);
}

int
solisten(struct socket *so, int backlog)
{
        int s = splnet(), error;

        error = (*so->so_proto->pr_usrreqs->pru_listen)(so);
        if (error) {
                splx(s);
                return (error);
        }
        if (so->so_comp.tqh_first == NULL)
                so->so_options |= SO_ACCEPTCONN;
        if (backlog < 0 || backlog > somaxconn)
                backlog = somaxconn;
        so->so_qlimit = backlog;
        splx(s);
        return (0);
}

void
sofree(struct socket *so)
{
        struct socket *head = so->so_head;

        if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0)
                return;
        if (head != NULL) {
                if (so->so_state & SS_INCOMP) {
                        TAILQ_REMOVE(&head->so_incomp, so, so_list);
                        head->so_incqlen--;
                } else if (so->so_state & SS_COMP) {
                        TAILQ_REMOVE(&head->so_comp, so, so_list);
                } else {
                        panic("sofree: not queued");
                }
                head->so_qlen--;
                so->so_state &= ~(SS_INCOMP|SS_COMP);
                so->so_head = NULL;
        }
        sbrelease(&so->so_snd);
        sorflush(so);
        FREE(so, M_SOCKET);
}

static void
rtems_socket_close_notify(struct socket *so)
{
        if (so->so_pgid) {
                rtems_event_system_send(so->so_pgid, RTEMS_EVENT_SYSTEM_NETWORK_CLOSE);
        }
}

static void
rtems_sockbuf_close_notify(struct socket *so, struct sockbuf *sb)
{
        if (sb->sb_flags & SB_WAIT) {
                rtems_event_system_send(sb->sb_sel.si_pid,
                    RTEMS_EVENT_SYSTEM_NETWORK_CLOSE);
        }

        if (sb->sb_wakeup)
                (*sb->sb_wakeup)(so, sb->sb_wakeuparg);
}

/*
 * Close a socket on last file table reference removal.
 * Initiate disconnect if connected.
 * Free socket when disconnect complete.
 */
int
soclose(struct socket *so)
{
        int s = splnet();               /* conservative */
        int error = 0;

        rtems_socket_close_notify(so);
        rtems_sockbuf_close_notify(so, &so->so_snd);
        rtems_sockbuf_close_notify(so, &so->so_rcv);

        if (so->so_options & SO_ACCEPTCONN) {
                struct socket *sp, *sonext;

                for (sp = so->so_incomp.tqh_first; sp != NULL; sp = sonext) {
                        sonext = sp->so_list.tqe_next;
                        (void) soabort(sp);
                }
                for (sp = so->so_comp.tqh_first; sp != NULL; sp = sonext) {
                        sonext = sp->so_list.tqe_next;
                        (void) soabort(sp);
                }
        }
        if (so->so_pcb == 0)
                goto discard;
        if (so->so_state & SS_ISCONNECTED) {
                if ((so->so_state & SS_ISDISCONNECTING) == 0) {
                        error = sodisconnect(so);
                        if (error)
                                goto drop;
                }
                if (so->so_options & SO_LINGER) {
                        if ((so->so_state & SS_ISDISCONNECTING) &&
                            (so->so_state & SS_NBIO))
                                goto drop;
                        while (so->so_state & SS_ISCONNECTED) {
                                soconnsleep (so);
                        }
                }
        }
drop:
        if (so->so_pcb) {
                int error2 = (*so->so_proto->pr_usrreqs->pru_detach)(so);
                if (error == 0)
                        error = error2;
        }
discard:
        if (so->so_state & SS_NOFDREF)
                panic("soclose: NOFDREF");
        so->so_state |= SS_NOFDREF;
        sofree(so);
        splx(s);
        return (error);
}

/*
 * Must be called at splnet...
 */
int
soabort(struct socket *so)
{

        return (*so->so_proto->pr_usrreqs->pru_abort)(so);
}

int
soaccept(struct socket *so, struct mbuf *nam)
{
        int s = splnet();
        int error;

        if ((so->so_state & SS_NOFDREF) == 0)
                panic("soaccept: !NOFDREF");
        so->so_state &= ~SS_NOFDREF;
        error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam);
        splx(s);
        return (error);
}

int
soconnect(struct socket *so, struct mbuf *nam)
{
        int s;
        int error;

        if (so->so_options & SO_ACCEPTCONN)
                return (EOPNOTSUPP);
        s = splnet();
        /*
         * If protocol is connection-based, can only connect once.
         * Otherwise, if connected, try to disconnect first.
         * This allows user to disconnect by connecting to, e.g.,
         * a null address.
         */
        if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
            ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
            (error = sodisconnect(so))))
                error = EISCONN;
        else
                error = (*so->so_proto->pr_usrreqs->pru_connect)(so, nam);
        splx(s);
        return (error);
}

int
soconnect2(struct socket *so1,struct socket *so2)
{
        int s = splnet();
        int error;

        error = (*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2);
        splx(s);
        return (error);
}

int
sodisconnect(struct socket *so)
{
        int s = splnet();
        int error;

        if ((so->so_state & SS_ISCONNECTED) == 0) {
                error = ENOTCONN;
                goto bad;
        }
        if (so->so_state & SS_ISDISCONNECTING) {
                error = EALREADY;
                goto bad;
        }
        error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so);
bad:
        splx(s);
        return (error);
}

#define SBLOCKWAIT(f)   (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
/*
 * Send on a socket.
 * If send must go all at once and message is larger than
 * send buffering, then hard error.
 * Lock against other senders.
 * If must go all at once and not enough room now, then
 * inform user that this would block and do nothing.
 * Otherwise, if nonblocking, send as much as possible.
 * The data to be sent is described by "uio" if nonzero,
 * otherwise by the mbuf chain "top" (which must be null
 * if uio is not).  Data provided in mbuf chain must be small
 * enough to send all at once.
 *
 * Returns nonzero on error, timeout or signal; callers
 * must check for short counts if EINTR/ERESTART are returned.
 * Data and control buffers are freed on return.
 */
int
sosend(struct socket *so, struct mbuf *addr, struct uio *uio,
    struct mbuf *top, struct mbuf *control, int flags)
{
        struct mbuf **mp;
        register struct mbuf *m;
        register long space, len, resid;
        int clen = 0, error, s, dontroute, mlen;
        int atomic = sosendallatonce(so) || top;

        if (uio)
                resid = uio->uio_resid;
        else
                resid = top->m_pkthdr.len;
        /*
         * In theory resid should be unsigned.
         * However, space must be signed, as it might be less than 0
         * if we over-committed, and we must use a signed comparison
         * of space and resid.  On the other hand, a negative resid
         * causes us to loop sending 0-length segments to the protocol.
         *
         * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
         * type sockets since that's an error.
         */
        if ((resid < 0) || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) {
                error = EINVAL;
                goto out;
        }

        dontroute =
            (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
            (so->so_proto->pr_flags & PR_ATOMIC);
        if (control)
                clen = control->m_len;
#define snderr(errno)   { error = errno; splx(s); goto release; }

restart:
        error = sblock(&so->so_snd, SBLOCKWAIT(flags));
        if (error)
                goto out;
        do {
                s = splnet();
                if (so->so_state & SS_CANTSENDMORE)
                        snderr(EPIPE);
                if (so->so_error) {
                        error = so->so_error;
                        so->so_error = 0;
                        splx(s);
                        goto release;
                }
                if ((so->so_state & SS_ISCONNECTED) == 0) {
                        /*
                         * `sendto' and `sendmsg' is allowed on a connection-
                         * based socket if it supports implied connect.
                         * Return ENOTCONN if not connected and no address is
                         * supplied.
                         */
                        if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
                            (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
                                if ((so->so_state & SS_ISCONFIRMING) == 0 &&
                                    !(resid == 0 && clen != 0))
                                        snderr(ENOTCONN);
                        } else if (addr == 0)
                            snderr(so->so_proto->pr_flags & PR_CONNREQUIRED ?
                                   ENOTCONN : EDESTADDRREQ);
                }
                space = sbspace(&so->so_snd);
                if (flags & MSG_OOB)
                        space += 1024;
                if ((atomic && resid > so->so_snd.sb_hiwat) ||
                    clen > so->so_snd.sb_hiwat)
                        snderr(EMSGSIZE);
                if (space < resid + clen && uio &&
                    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
                        if (so->so_state & SS_NBIO)
                                snderr(EWOULDBLOCK);
                        sbunlock(&so->so_snd);
                        error = sbwait(&so->so_snd);
                        splx(s);
                        if (error)
                                goto out;
                        goto restart;
                }
                splx(s);
                mp = &top;
                space -= clen;
                do {
                    if (uio == NULL) {
                        /*
                         * Data is prepackaged in "top".
                         */
                        resid = 0;
                        if (flags & MSG_EOR)
                                top->m_flags |= M_EOR;
                    } else do {
                        if (top == 0) {
                                MGETHDR(m, M_WAIT, MT_DATA);
                                mlen = MHLEN;
                                m->m_pkthdr.len = 0;
                                m->m_pkthdr.rcvif = (struct ifnet *)0;
                        } else {
                                MGET(m, M_WAIT, MT_DATA);
                                mlen = MLEN;
                        }
                        if (resid >= MINCLSIZE) {
                                MCLGET(m, M_WAIT);
                                if ((m->m_flags & M_EXT) == 0)
                                        goto nopages;
                                mlen = MCLBYTES;
                                len = min(min(mlen, resid), space);
                        } else {
nopages:
                                len = min(min(mlen, resid), space);
                                /*
                                 * For datagram protocols, leave room
                                 * for protocol headers in first mbuf.
                                 */
                                if (atomic && top == 0 && len < mlen)
                                        MH_ALIGN(m, len);
                        }
                        space -= len;
                        error = uiomove(mtod(m, caddr_t), (int)len, uio);
                        resid = uio->uio_resid;
                        m->m_len = len;
                        *mp = m;
                        top->m_pkthdr.len += len;
                        if (error)
                                goto release;
                        mp = &m->m_next;
                        if (resid <= 0) {
                                if (flags & MSG_EOR)
                                        top->m_flags |= M_EOR;
                                break;
                        }
                    } while (space > 0 && atomic);
                    if (dontroute)
                            so->so_options |= SO_DONTROUTE;
                    s = splnet();                               /* XXX */
                    error = (*so->so_proto->pr_usrreqs->pru_send)(so,
                        (flags & MSG_OOB) ? PRUS_OOB :
                        /*
                         * If the user set MSG_EOF, the protocol
                         * understands this flag and nothing left to
                         * send then use PRU_SEND_EOF instead of PRU_SEND.
                         */
                        ((flags & MSG_EOF) &&
                         (so->so_proto->pr_flags & PR_IMPLOPCL) &&
                         (resid <= 0)) ?
                                PRUS_EOF : 0,
                        top, addr, control);
                    splx(s);
                    if (dontroute)
                            so->so_options &= ~SO_DONTROUTE;
                    clen = 0;
                    control = 0;
                    top = 0;
                    mp = &top;
                    if (error)
                        goto release;
                } while (resid && space > 0);
        } while (resid);

release:
        sbunlock(&so->so_snd);
out:
        if (top)
                m_freem(top);
        if (control)
                m_freem(control);
        return (error);
}

/*
 * Implement receive operations on a socket.
 * We depend on the way that records are added to the sockbuf
 * by sbappend*.  In particular, each record (mbufs linked through m_next)
 * must begin with an address if the protocol so specifies,
 * followed by an optional mbuf or mbufs containing ancillary data,
 * and then zero or more mbufs of data.
 * In order to avoid blocking network interrupts for the entire time here,
 * we splx() while doing the actual copy to user space.
 * Although the sockbuf is locked, new data may still be appended,
 * and thus we must maintain consistency of the sockbuf during that time.
 *
 * The caller may receive the data as a single mbuf chain by supplying
 * an mbuf **mp0 for use in returning the chain.  The uio is then used
 * only for the count in uio_resid.
 */
int
soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio,
    struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
{
        register struct mbuf *m, **mp;
        register int flags, len, error, s, offset;
        struct protosw *pr = so->so_proto;
        struct mbuf *nextrecord;
        int moff, type = 0;
        int orig_resid = uio->uio_resid;

        mp = mp0;
        if (paddr)
                *paddr = 0;
        if (controlp)
                *controlp = 0;
        if (flagsp)
                flags = *flagsp &~ MSG_EOR;
        else
                flags = 0;
        if (flags & MSG_OOB) {
                m = m_get(M_WAIT, MT_DATA);
                error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
                if (error)
                        goto bad;
                do {
                        error = uiomove(mtod(m, caddr_t),
                            (int) min(uio->uio_resid, m->m_len), uio);
                        m = m_free(m);
                } while (uio->uio_resid && error == 0 && m);
bad:
                if (m)
                        m_freem(m);
                return (error);
        }
        if (mp)
                *mp = (struct mbuf *)0;
        if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
                (*pr->pr_usrreqs->pru_rcvd)(so, 0);

restart:
        error = sblock(&so->so_rcv, SBLOCKWAIT(flags));
        if (error)
                return (error);
        s = splnet();

        m = so->so_rcv.sb_mb;
        /*
         * If we have less data than requested, block awaiting more
         * (subject to any timeout) if:
         *   1. the current count is less than the low water mark, or
         *   2. MSG_WAITALL is set, and it is possible to do the entire
         *      receive operation at once if we block (resid <= hiwat).
         *   3. MSG_DONTWAIT is not set
         * If MSG_WAITALL is set but resid is larger than the receive buffer,
         * we have to do the receive in sections, and thus risk returning
         * a short count if a timeout or signal occurs after we start.
         */
        if (m == 0 || (((flags & MSG_DONTWAIT) == 0 &&
            so->so_rcv.sb_cc < uio->uio_resid) &&
            (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
            ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
            m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
#ifdef DIAGNOSTIC
                if (m == 0 && so->so_rcv.sb_cc)
                        panic("receive 1");
#endif
                if (so->so_error) {
                        if (m)
                                goto dontblock;
                        error = so->so_error;
                        if ((flags & MSG_PEEK) == 0)
                                so->so_error = 0;
                        goto release;
                }
                if (so->so_state & SS_CANTRCVMORE) {
                        if (m)
                                goto dontblock;
                        else
                                goto release;
                }
                for (; m; m = m->m_next)
                        if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
                                m = so->so_rcv.sb_mb;
                                goto dontblock;
                        }
                if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
                    (so->so_proto->pr_flags & PR_CONNREQUIRED)) {
                        error = ENOTCONN;
                        goto release;
                }
                if (uio->uio_resid == 0)
                        goto release;
                if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT)) {
                        error = EWOULDBLOCK;
                        goto release;
                }
                sbunlock(&so->so_rcv);
                error = sbwait(&so->so_rcv);
                splx(s);
                if (error)
                        return (error);
                goto restart;
        }
dontblock:
        nextrecord = m->m_nextpkt;
        if (pr->pr_flags & PR_ADDR) {
#ifdef DIAGNOSTIC
                if (m->m_type != MT_SONAME)
                        panic("receive 1a");
#endif
                orig_resid = 0;
                if (flags & MSG_PEEK) {
                        if (paddr)
                                *paddr = m_copy(m, 0, m->m_len);
                        m = m->m_next;
                } else {
                        sbfree(&so->so_rcv, m);
                        if (paddr) {
                                *paddr = m;
                                so->so_rcv.sb_mb = m->m_next;
                                m->m_next = 0;
                                m = so->so_rcv.sb_mb;
                        } else {
                                MFREE(m, so->so_rcv.sb_mb);
                                m = so->so_rcv.sb_mb;
                        }
                }
        }
        while (m && m->m_type == MT_CONTROL && error == 0) {
                if (flags & MSG_PEEK) {
                        if (controlp)
                                *controlp = m_copy(m, 0, m->m_len);
                        m = m->m_next;
                } else {
                        sbfree(&so->so_rcv, m);
                        if (controlp) {
                                if (pr->pr_domain->dom_externalize &&
                                    mtod(m, struct cmsghdr *)->cmsg_type ==
                                    SCM_RIGHTS)
                                   error = (*pr->pr_domain->dom_externalize)(m);
                                *controlp = m;
                                so->so_rcv.sb_mb = m->m_next;
                                m->m_next = 0;
                                m = so->so_rcv.sb_mb;
                        } else {
                                MFREE(m, so->so_rcv.sb_mb);
                                m = so->so_rcv.sb_mb;
                        }
                }
                if (controlp) {
                        orig_resid = 0;
                        controlp = &(*controlp)->m_next;
                }
        }
        if (m) {
                if ((flags & MSG_PEEK) == 0)
                        m->m_nextpkt = nextrecord;
                type = m->m_type;
                if (type == MT_OOBDATA)
                        flags |= MSG_OOB;
        }
        moff = 0;
        offset = 0;
        while (m && uio->uio_resid > 0 && error == 0) {
                if (m->m_type == MT_OOBDATA) {
                        if (type != MT_OOBDATA)
                                break;
                } else if (type == MT_OOBDATA)
                        break;
#ifdef DIAGNOSTIC
                else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
                        panic("receive 3");
#endif
                so->so_state &= ~SS_RCVATMARK;
                len = uio->uio_resid;
                if (so->so_oobmark && len > so->so_oobmark - offset)
                        len = so->so_oobmark - offset;
                if (len > m->m_len - moff)
                        len = m->m_len - moff;
                /*
                 * If mp is set, just pass back the mbufs.
                 * Otherwise copy them out via the uio, then free.
                 * Sockbuf must be consistent here (points to current mbuf,
                 * it points to next record) when we drop priority;
                 * we must note any additions to the sockbuf when we
                 * block interrupts again.
                 */
                if (mp == 0) {
                        splx(s);
                        error = uiomove(mtod(m, caddr_t) + moff, (int)len, uio);
                        s = splnet();
                        if (error)
                                goto release;
                } else
                        uio->uio_resid -= len;
                if (len == m->m_len - moff) {
                        if (m->m_flags & M_EOR)
                                flags |= MSG_EOR;
                        if (flags & MSG_PEEK) {
                                m = m->m_next;
                                moff = 0;
                        } else {
                                nextrecord = m->m_nextpkt;
                                sbfree(&so->so_rcv, m);
                                if (mp) {
                                        *mp = m;
                                        mp = &m->m_next;
                                        so->so_rcv.sb_mb = m = m->m_next;
                                        *mp = (struct mbuf *)0;
                                } else {
                                        MFREE(m, so->so_rcv.sb_mb);
                                        m = so->so_rcv.sb_mb;
                                }
                                if (m)
                                        m->m_nextpkt = nextrecord;
                        }
                } else {
                        if (flags & MSG_PEEK)
                                moff += len;
                        else {
                                if (mp)
                                        *mp = m_copym(m, 0, len, M_WAIT);
                                m->m_data += len;
                                m->m_len -= len;
                                so->so_rcv.sb_cc -= len;
                        }
                }
                if (so->so_oobmark) {
                        if ((flags & MSG_PEEK) == 0) {
                                so->so_oobmark -= len;
                                if (so->so_oobmark == 0) {
                                        so->so_state |= SS_RCVATMARK;
                                        break;
                                }
                        } else {
                                offset += len;
                                if (offset == so->so_oobmark)
                                        break;
                        }
                }
                if (flags & MSG_EOR)
                        break;
                /*
                 * If the MSG_WAITALL flag is set (for non-atomic socket),
                 * we must not quit until "uio->uio_resid == 0" or an error
                 * termination.  If a signal/timeout occurs, return
                 * with a short count but without error.
                 * Keep sockbuf locked against other readers.
                 */
                while (flags & MSG_WAITALL && m == 0 && uio->uio_resid > 0 &&
                    !sosendallatonce(so) && !nextrecord) {
                        if (so->so_error || so->so_state & SS_CANTRCVMORE)
                                break;
                        error = sbwait(&so->so_rcv);
                        if (error) {
                                if (error != ENXIO)
                                        sbunlock(&so->so_rcv);
                                splx(s);
                                return (0);
                        }
                        m = so->so_rcv.sb_mb;
                        if (m)
                                nextrecord = m->m_nextpkt;
                }
        }

        if (m && pr->pr_flags & PR_ATOMIC) {
                flags |= MSG_TRUNC;
                if ((flags & MSG_PEEK) == 0)
                        (void) sbdroprecord(&so->so_rcv);
        }
        if ((flags & MSG_PEEK) == 0) {
                if (m == 0)
                        so->so_rcv.sb_mb = nextrecord;
                if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
                        (*pr->pr_usrreqs->pru_rcvd)(so, flags);
        }
        if (orig_resid == uio->uio_resid && orig_resid &&
            (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
                sbunlock(&so->so_rcv);
                splx(s);
                goto restart;
        }

        if (flagsp)
                *flagsp |= flags;
release:
        sbunlock(&so->so_rcv);
        splx(s);
        return (error);
}

int
soshutdown(struct socket *so, int how )
{
        register struct protosw *pr = so->so_proto;

        how++;
        if (how & FREAD)
                sorflush(so);
        if (how & FWRITE)
                return ((*pr->pr_usrreqs->pru_shutdown)(so));
        return (0);
}

void
sorflush(struct socket *so)
{
        register struct sockbuf *sb = &so->so_rcv;
        register struct protosw *pr = so->so_proto;
        register int s;
        struct sockbuf asb;

        sb->sb_flags |= SB_NOINTR;
        (void) sblock(sb, M_WAITOK);
        s = splimp();
        socantrcvmore(so);
        sbunlock(sb);
        asb = *sb;
        bzero((caddr_t)sb, sizeof (*sb));
        splx(s);
        if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
                (*pr->pr_domain->dom_dispose)(asb.sb_mb);
        sbrelease(&asb);
}

int
sosetopt(struct socket *so, int level, int optname, struct mbuf *m0)
{
        int error = 0;
        register struct mbuf *m = m0;

        if (level != SOL_SOCKET) {
                if (so->so_proto && so->so_proto->pr_ctloutput)
                        return ((*so->so_proto->pr_ctloutput)
                                  (PRCO_SETOPT, so, level, optname, &m0));
                error = ENOPROTOOPT;
        } else {
                switch (optname) {

                case SO_LINGER:
                        if (m == NULL || m->m_len != sizeof (struct linger)) {
                                error = EINVAL;
                                goto bad;
                        }
                        so->so_linger = mtod(m, struct linger *)->l_linger;
                        /* fall thru... */

                case SO_DEBUG:
                case SO_KEEPALIVE:
                case SO_DONTROUTE:
                case SO_USELOOPBACK:
                case SO_BROADCAST:
                case SO_REUSEADDR:
                case SO_REUSEPORT:
                case SO_OOBINLINE:
                case SO_TIMESTAMP:
                        if (m == NULL || m->m_len < sizeof (int)) {
                                error = EINVAL;
                                goto bad;
                        }
                        if (*mtod(m, int *))
                                so->so_options |= optname;
                        else
                                so->so_options &= ~optname;
                        break;

                case SO_SNDBUF:
                case SO_RCVBUF:
                case SO_SNDLOWAT:
                case SO_RCVLOWAT:
                    {
                        int optval;

                        if (m == NULL || m->m_len < sizeof (int)) {
                                error = EINVAL;
                                goto bad;
                        }

                        /*
                         * Values < 1 make no sense for any of these
                         * options, so disallow them.
                         */
                        optval = *mtod(m, int *);
                        if (optval < 1) {
                                error = EINVAL;
                                goto bad;
                        }

                        switch (optname) {

                        case SO_SNDBUF:
                        case SO_RCVBUF:
                                if (sbreserve(optname == SO_SNDBUF ?
                                    &so->so_snd : &so->so_rcv,
                                    (u_long) optval) == 0) {
                                        error = ENOBUFS;
                                        goto bad;
                                }
                                break;

                        /*
                         * Make sure the low-water is never greater than
                         * the high-water.
                         */
                        case SO_SNDLOWAT:
                                so->so_snd.sb_lowat =
                                    (optval > so->so_snd.sb_hiwat) ?
                                    so->so_snd.sb_hiwat : optval;
                                break;
                        case SO_RCVLOWAT:
                                so->so_rcv.sb_lowat =
                                    (optval > so->so_rcv.sb_hiwat) ?
                                    so->so_rcv.sb_hiwat : optval;
                                break;
                        }
                        break;
                    }

                case SO_SNDTIMEO:
                case SO_RCVTIMEO:
                    {
                        struct timeval *tv;
                        unsigned long val;

                        if (m == NULL || m->m_len < sizeof (*tv)) {
                                error = EINVAL;
                                goto bad;
                        }
                        tv = mtod(m, struct timeval *);
                        if (tv->tv_sec >= (ULONG_MAX - hz) / hz) {
                                error = EDOM;
                                goto bad;
                        }

                        val = tv->tv_sec * hz + tv->tv_usec / tick;
                        if ((val == 0) && (tv->tv_sec || tv->tv_usec))
                                val = 1;

                        switch (optname) {

                        case SO_SNDTIMEO:
                                so->so_snd.sb_timeo = val;
                                break;
                        case SO_RCVTIMEO:
                                so->so_rcv.sb_timeo = val;
                                break;
                        }
                        break;
                    }

                case SO_PRIVSTATE:
                        /* we don't care what the parameter is... */
                        so->so_state &= ~SS_PRIV;
                        break;

                case SO_SNDWAKEUP:
                case SO_RCVWAKEUP:
                    {
                        /* RTEMS addition.  */
                        struct sockwakeup *sw;
                        struct sockbuf *sb;

                        if (m == NULL
                            || m->m_len != sizeof (struct sockwakeup)) {
                                error = EINVAL;
                                goto bad;
                        }
                        sw = mtod(m, struct sockwakeup *);
                        sb = (optname == SO_SNDWAKEUP
                              ? &so->so_snd
                              : &so->so_rcv);
                        sb->sb_wakeup = sw->sw_pfn;
                        sb->sb_wakeuparg = sw->sw_arg;
                        if (sw->sw_pfn)
                                sb->sb_flags |= SB_ASYNC;
                        else
                                sb->sb_flags &=~ SB_ASYNC;
                        break;
                    }

                default:
                        error = ENOPROTOOPT;
                        break;
                }
                if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
                        (void) ((*so->so_proto->pr_ctloutput)
                                  (PRCO_SETOPT, so, level, optname, &m0));
                        m = NULL;       /* freed by protocol */
                }
        }
bad:
        if (m)
                (void) m_free(m);
        return (error);
}

int
sogetopt(struct socket *so, int level, int optname, struct mbuf **mp)
{
        register struct mbuf *m;

        if (level != SOL_SOCKET) {
                if (so->so_proto && so->so_proto->pr_ctloutput) {
                        return ((*so->so_proto->pr_ctloutput)
                                  (PRCO_GETOPT, so, level, optname, mp));
                } else
                        return (ENOPROTOOPT);
        } else {
                m = m_get(M_WAIT, MT_SOOPTS);
                m->m_len = sizeof (int);

                switch (optname) {

                case SO_LINGER:
                        m->m_len = sizeof (struct linger);
                        mtod(m, struct linger *)->l_onoff =
                                so->so_options & SO_LINGER;
                        mtod(m, struct linger *)->l_linger = so->so_linger;
                        break;

                case SO_USELOOPBACK:
                case SO_DONTROUTE:
                case SO_DEBUG:
                case SO_KEEPALIVE:
                case SO_REUSEADDR:
                case SO_REUSEPORT:
                case SO_BROADCAST:
                case SO_OOBINLINE:
                case SO_TIMESTAMP:
                        *mtod(m, int *) = so->so_options & optname;
                        break;

                case SO_PRIVSTATE:
                        *mtod(m, int *) = so->so_state & SS_PRIV;
                        break;

                case SO_TYPE:
                        *mtod(m, int *) = so->so_type;
                        break;

                case SO_ERROR:
                        *mtod(m, int *) = so->so_error;
                        so->so_error = 0;
                        break;

                case SO_SNDBUF:
                        *mtod(m, int *) = so->so_snd.sb_hiwat;
                        break;

                case SO_RCVBUF:
                        *mtod(m, int *) = so->so_rcv.sb_hiwat;
                        break;

                case SO_SNDLOWAT:
                        *mtod(m, int *) = so->so_snd.sb_lowat;
                        break;

                case SO_RCVLOWAT:
                        *mtod(m, int *) = so->so_rcv.sb_lowat;
                        break;

                case SO_SNDTIMEO:
                case SO_RCVTIMEO:
                    {
                        unsigned long val = (optname == SO_SNDTIMEO ?
                             so->so_snd.sb_timeo : so->so_rcv.sb_timeo);

                        m->m_len = sizeof(struct timeval);
                        mtod(m, struct timeval *)->tv_sec = val / hz;
                        mtod(m, struct timeval *)->tv_usec =
                            (val % hz) * tick;
                        break;
                    }

                case SO_SNDWAKEUP:
                case SO_RCVWAKEUP:
                    {
                        struct sockbuf *sb;
                        struct sockwakeup *sw;

                        /* RTEMS additions.  */
                        sb = (optname == SO_SNDWAKEUP
                              ? &so->so_snd
                              : &so->so_rcv);
                        m->m_len = sizeof (struct sockwakeup);
                        sw = mtod(m, struct sockwakeup *);
                        sw->sw_pfn = sb->sb_wakeup;
                        sw->sw_arg = sb->sb_wakeuparg;
                        break;
                    }

                default:
                        (void)m_free(m);
                        return (ENOPROTOOPT);
                }
                *mp = m;
                return (0);
        }
}

void
sohasoutofband(struct socket *so)
{
#if 0   /* FIXME: For now we just ignore out of band data */
        struct proc *p;

        if (so->so_pgid < 0)
                gsignal(-so->so_pgid, SIGURG);
        else if (so->so_pgid > 0 && (p = pfind(so->so_pgid)) != 0)
                psignal(p, SIGURG);
        selwakeup(&so->so_rcv.sb_sel);
#endif
}