slirp/socket.c

   1 /*
   2  * Copyright (c) 1995 Danny Gasparovski.
   3  *
   4  * Please read the file COPYRIGHT for the
   5  * terms and conditions of the copyright.
   6  */
   7
   8 #define WANT_SYS_IOCTL_H
   9 #include <slirp.h>
  10 #include "ip_icmp.h"
  11 #ifdef __sun__
  12 #include <sys/filio.h>
  13 #endif
  14
  15 static void sofcantrcvmore(struct socket *so);
  16 static void sofcantsendmore(struct socket *so);
  17
  18 #if 0
  19 static void
  20 so_init()
  21 {
  22         /* Nothing yet */
  23 }
  24 #endif
  25
  26 struct socket *
  27 solookup(head, laddr, lport, faddr, fport)
  28         struct socket *head;
  29         struct in_addr laddr;
  30         u_int lport;
  31         struct in_addr faddr;
  32         u_int fport;
  33 {
  34         struct socket *so;
  35
  36         for (so = head->so_next; so != head; so = so->so_next) {
  37                 if (so->so_lport == lport &&
  38                     so->so_laddr.s_addr == laddr.s_addr &&
  39                     so->so_faddr.s_addr == faddr.s_addr &&
  40                     so->so_fport == fport)
  41                    break;
  42         }
  43
  44         if (so == head)
  45            return (struct socket *)NULL;
  46         return so;
  47
  48 }
  49
  50 /*
  51  * Create a new socket, initialise the fields
  52  * It is the responsibility of the caller to
  53  * insque() it into the correct linked-list
  54  */
  55 struct socket *
  56 socreate()
  57 {
  58   struct socket *so;
  59
  60   so = (struct socket *)malloc(sizeof(struct socket));
  61   if(so) {
  62     memset(so, 0, sizeof(struct socket));
  63     so->so_state = SS_NOFDREF;
  64     so->s = -1;
  65   }
  66   return(so);
  67 }
  68
  69 /*
  70  * remque and free a socket, clobber cache
  71  */
  72 void
  73 sofree(so)
  74         struct socket *so;
  75 {
  76   if (so->so_emu==EMU_RSH && so->extra) {
  77         sofree(so->extra);
  78         so->extra=NULL;
  79   }
  80   if (so == tcp_last_so)
  81     tcp_last_so = &tcb;
  82   else if (so == udp_last_so)
  83     udp_last_so = &udb;
  84
  85   m_free(so->so_m);
  86
  87   if(so->so_next && so->so_prev)
  88     remque(so);  /* crashes if so is not in a queue */
  89
  90   free(so);
  91 }
  92
  93 /*
  94  * Read from so's socket into sb_snd, updating all relevant sbuf fields
  95  * NOTE: This will only be called if it is select()ed for reading, so
  96  * a read() of 0 (or less) means it's disconnected
  97  */
  98 int
  99 soread(so)
 100         struct socket *so;
 101 {
 102         int n, nn, lss, total;
 103         struct sbuf *sb = &so->so_snd;
 104         int len = sb->sb_datalen - sb->sb_cc;
 105         struct iovec iov[2];
 106         int mss = so->so_tcpcb->t_maxseg;
 107
 108         DEBUG_CALL("soread");
 109         DEBUG_ARG("so = %lx", (long )so);
 110
 111         /*
 112          * No need to check if there's enough room to read.
 113          * soread wouldn't have been called if there weren't
 114          */
 115
 116         len = sb->sb_datalen - sb->sb_cc;
 117
 118         iov[0].iov_base = sb->sb_wptr;
 119         iov[1].iov_base = NULL;
 120         iov[1].iov_len = 0;
 121         if (sb->sb_wptr < sb->sb_rptr) {
 122                 iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
 123                 /* Should never succeed, but... */
 124                 if (iov[0].iov_len > len)
 125                    iov[0].iov_len = len;
 126                 if (iov[0].iov_len > mss)
 127                    iov[0].iov_len -= iov[0].iov_len%mss;
 128                 n = 1;
 129         } else {
 130                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
 131                 /* Should never succeed, but... */
 132                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 133                 len -= iov[0].iov_len;
 134                 if (len) {
 135                         iov[1].iov_base = sb->sb_data;
 136                         iov[1].iov_len = sb->sb_rptr - sb->sb_data;
 137                         if(iov[1].iov_len > len)
 138                            iov[1].iov_len = len;
 139                         total = iov[0].iov_len + iov[1].iov_len;
 140                         if (total > mss) {
 141                                 lss = total%mss;
 142                                 if (iov[1].iov_len > lss) {
 143                                         iov[1].iov_len -= lss;
 144                                         n = 2;
 145                                 } else {
 146                                         lss -= iov[1].iov_len;
 147                                         iov[0].iov_len -= lss;
 148                                         n = 1;
 149                                 }
 150                         } else
 151                                 n = 2;
 152                 } else {
 153                         if (iov[0].iov_len > mss)
 154                            iov[0].iov_len -= iov[0].iov_len%mss;
 155                         n = 1;
 156                 }
 157         }
 158
 159 #ifdef HAVE_READV
 160         nn = readv(so->s, (struct iovec *)iov, n);
 161         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 162 #else
 163         nn = recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
 164 #endif
 165         if (nn <= 0) {
 166                 if (nn < 0 && (errno == EINTR || errno == EAGAIN))
 167                         return 0;
 168                 else {
 169                         DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
 170                         sofcantrcvmore(so);
 171                         tcp_sockclosed(sototcpcb(so));
 172                         return -1;
 173                 }
 174         }
 175
 176 #ifndef HAVE_READV
 177         /*
 178          * If there was no error, try and read the second time round
 179          * We read again if n = 2 (ie, there's another part of the buffer)
 180          * and we read as much as we could in the first read
 181          * We don't test for <= 0 this time, because there legitimately
 182          * might not be any more data (since the socket is non-blocking),
 183          * a close will be detected on next iteration.
 184          * A return of -1 wont (shouldn't) happen, since it didn't happen above
 185          */
 186         if (n == 2 && nn == iov[0].iov_len) {
 187             int ret;
 188             ret = recv(so->s, iov[1].iov_base, iov[1].iov_len,0);
 189             if (ret > 0)
 190                 nn += ret;
 191         }
 192
 193         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 194 #endif
 195
 196         /* Update fields */
 197         sb->sb_cc += nn;
 198         sb->sb_wptr += nn;
 199         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 200                 sb->sb_wptr -= sb->sb_datalen;
 201         return nn;
 202 }
 203
 204 /*
 205  * Get urgent data
 206  *
 207  * When the socket is created, we set it SO_OOBINLINE,
 208  * so when OOB data arrives, we soread() it and everything
 209  * in the send buffer is sent as urgent data
 210  */
 211 void
 212 sorecvoob(so)
 213         struct socket *so;
 214 {
 215         struct tcpcb *tp = sototcpcb(so);
 216
 217         DEBUG_CALL("sorecvoob");
 218         DEBUG_ARG("so = %lx", (long)so);
 219
 220         /*
 221          * We take a guess at how much urgent data has arrived.
 222          * In most situations, when urgent data arrives, the next
 223          * read() should get all the urgent data.  This guess will
 224          * be wrong however if more data arrives just after the
 225          * urgent data, or the read() doesn't return all the
 226          * urgent data.
 227          */
 228         soread(so);
 229         tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 230         tp->t_force = 1;
 231         tcp_output(tp);
 232         tp->t_force = 0;
 233 }
 234
 235 /*
 236  * Send urgent data
 237  * There's a lot duplicated code here, but...
 238  */
 239 int
 240 sosendoob(so)
 241         struct socket *so;
 242 {
 243         struct sbuf *sb = &so->so_rcv;
 244         char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
 245
 246         int n, len;
 247
 248         DEBUG_CALL("sosendoob");
 249         DEBUG_ARG("so = %lx", (long)so);
 250         DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
 251
 252         if (so->so_urgc > 2048)
 253            so->so_urgc = 2048; /* XXXX */
 254
 255         if (sb->sb_rptr < sb->sb_wptr) {
 256                 /* We can send it directly */
 257                 n = send(so->s, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 258                 so->so_urgc -= n;
 259
 260                 DEBUG_MISC((dfd, " --- sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 261         } else {
 262                 /*
 263                  * Since there's no sendv or sendtov like writev,
 264                  * we must copy all data to a linear buffer then
 265                  * send it all
 266                  */
 267                 len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 268                 if (len > so->so_urgc) len = so->so_urgc;
 269                 memcpy(buff, sb->sb_rptr, len);
 270                 so->so_urgc -= len;
 271                 if (so->so_urgc) {
 272                         n = sb->sb_wptr - sb->sb_data;
 273                         if (n > so->so_urgc) n = so->so_urgc;
 274                         memcpy((buff + len), sb->sb_data, n);
 275                         so->so_urgc -= n;
 276                         len += n;
 277                 }
 278                 n = send(so->s, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 279 #ifdef DEBUG
 280                 if (n != len)
 281                    DEBUG_ERROR((dfd, "Didn't send all data urgently XXXXX\n"));
 282 #endif
 283                 DEBUG_MISC((dfd, " ---2 sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 284         }
 285
 286         sb->sb_cc -= n;
 287         sb->sb_rptr += n;
 288         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 289                 sb->sb_rptr -= sb->sb_datalen;
 290
 291         return n;
 292 }
 293
 294 /*
 295  * Write data from so_rcv to so's socket,
 296  * updating all sbuf field as necessary
 297  */
 298 int
 299 sowrite(so)
 300         struct socket *so;
 301 {
 302         int  n,nn;
 303         struct sbuf *sb = &so->so_rcv;
 304         int len = sb->sb_cc;
 305         struct iovec iov[2];
 306
 307         DEBUG_CALL("sowrite");
 308         DEBUG_ARG("so = %lx", (long)so);
 309
 310         if (so->so_urgc) {
 311                 sosendoob(so);
 312                 if (sb->sb_cc == 0)
 313                         return 0;
 314         }
 315
 316         /*
 317          * No need to check if there's something to write,
 318          * sowrite wouldn't have been called otherwise
 319          */
 320
 321         len = sb->sb_cc;
 322
 323         iov[0].iov_base = sb->sb_rptr;
 324         iov[1].iov_base = NULL;
 325         iov[1].iov_len = 0;
 326         if (sb->sb_rptr < sb->sb_wptr) {
 327                 iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;
 328                 /* Should never succeed, but... */
 329                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 330                 n = 1;
 331         } else {
 332                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 333                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 334                 len -= iov[0].iov_len;
 335                 if (len) {
 336                         iov[1].iov_base = sb->sb_data;
 337                         iov[1].iov_len = sb->sb_wptr - sb->sb_data;
 338                         if (iov[1].iov_len > len) iov[1].iov_len = len;
 339                         n = 2;
 340                 } else
 341                         n = 1;
 342         }
 343         /* Check if there's urgent data to send, and if so, send it */
 344
 345 #ifdef HAVE_READV
 346         nn = writev(so->s, (const struct iovec *)iov, n);
 347
 348         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 349 #else
 350         nn = send(so->s, iov[0].iov_base, iov[0].iov_len,0);
 351 #endif
 352         /* This should never happen, but people tell me it does *shrug* */
 353         if (nn < 0 && (errno == EAGAIN || errno == EINTR))
 354                 return 0;
 355
 356         if (nn <= 0) {
 357                 DEBUG_MISC((dfd, " --- sowrite disconnected, so->so_state = %x, errno = %d\n",
 358                         so->so_state, errno));
 359                 sofcantsendmore(so);
 360                 tcp_sockclosed(sototcpcb(so));
 361                 return -1;
 362         }
 363
 364 #ifndef HAVE_READV
 365         if (n == 2 && nn == iov[0].iov_len) {
 366             int ret;
 367             ret = send(so->s, iov[1].iov_base, iov[1].iov_len,0);
 368             if (ret > 0)
 369                 nn += ret;
 370         }
 371         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 372 #endif
 373
 374         /* Update sbuf */
 375         sb->sb_cc -= nn;
 376         sb->sb_rptr += nn;
 377         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 378                 sb->sb_rptr -= sb->sb_datalen;
 379
 380         /*
 381          * If in DRAIN mode, and there's no more data, set
 382          * it CANTSENDMORE
 383          */
 384         if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)
 385                 sofcantsendmore(so);
 386
 387         return nn;
 388 }
 389
 390 /*
 391  * recvfrom() a UDP socket
 392  */
 393 void
 394 sorecvfrom(so)
 395         struct socket *so;
 396 {
 397         struct sockaddr_in addr;
 398         socklen_t addrlen = sizeof(struct sockaddr_in);
 399
 400         DEBUG_CALL("sorecvfrom");
 401         DEBUG_ARG("so = %lx", (long)so);
 402
 403         if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
 404           char buff[256];
 405           int len;
 406
 407           len = recvfrom(so->s, buff, 256, 0,
 408                          (struct sockaddr *)&addr, &addrlen);
 409           /* XXX Check if reply is "correct"? */
 410
 411           if(len == -1 || len == 0) {
 412             u_char code=ICMP_UNREACH_PORT;
 413
 414             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 415             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 416
 417             DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
 418                         errno,strerror(errno)));
 419             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 420           } else {
 421             icmp_reflect(so->so_m);
 422             so->so_m = 0; /* Don't m_free() it again! */
 423           }
 424           /* No need for this socket anymore, udp_detach it */
 425           udp_detach(so);
 426         } else {                                /* A "normal" UDP packet */
 427           struct mbuf *m;
 428           int len, n;
 429
 430           if (!(m = m_get())) return;
 431           m->m_data += IF_MAXLINKHDR;
 432
 433           /*
 434            * XXX Shouldn't FIONREAD packets destined for port 53,
 435            * but I don't know the max packet size for DNS lookups
 436            */
 437           len = M_FREEROOM(m);
 438           /* if (so->so_fport != htons(53)) { */
 439           ioctlsocket(so->s, FIONREAD, &n);
 440
 441           if (n > len) {
 442             n = (m->m_data - m->m_dat) + m->m_len + n + 1;
 443             m_inc(m, n);
 444             len = M_FREEROOM(m);
 445           }
 446           /* } */
 447
 448           m->m_len = recvfrom(so->s, m->m_data, len, 0,
 449                               (struct sockaddr *)&addr, &addrlen);
 450           DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n",
 451                       m->m_len, errno,strerror(errno)));
 452           if(m->m_len<0) {
 453             u_char code=ICMP_UNREACH_PORT;
 454
 455             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 456             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 457
 458             DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code));
 459             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 460             m_free(m);
 461           } else {
 462           /*
 463            * Hack: domain name lookup will be used the most for UDP,
 464            * and since they'll only be used once there's no need
 465            * for the 4 minute (or whatever) timeout... So we time them
 466            * out much quicker (10 seconds  for now...)
 467            */
 468             if (so->so_expire) {
 469               if (so->so_fport == htons(53))
 470                 so->so_expire = curtime + SO_EXPIREFAST;
 471               else
 472                 so->so_expire = curtime + SO_EXPIRE;
 473             }
 474
 475             /*          if (m->m_len == len) {
 476              *                  m_inc(m, MINCSIZE);
 477              *                  m->m_len = 0;
 478              *          }
 479              */
 480
 481             /*
 482              * If this packet was destined for CTL_ADDR,
 483              * make it look like that's where it came from, done by udp_output
 484              */
 485             udp_output(so, m, &addr);
 486           } /* rx error */
 487         } /* if ping packet */
 488 }
 489
 490 /*
 491  * sendto() a socket
 492  */
 493 int
 494 sosendto(so, m)
 495         struct socket *so;
 496         struct mbuf *m;
 497 {
 498         int ret;
 499         struct sockaddr_in addr;
 500
 501         DEBUG_CALL("sosendto");
 502         DEBUG_ARG("so = %lx", (long)so);
 503         DEBUG_ARG("m = %lx", (long)m);
 504
 505         addr.sin_family = AF_INET;
 506         if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
 507           /* It's an alias */
 508           switch(ntohl(so->so_faddr.s_addr) & 0xff) {
 509           case CTL_DNS:
 510             addr.sin_addr = dns_addr;
 511             break;
 512           case CTL_ALIAS:
 513           default:
 514             addr.sin_addr = loopback_addr;
 515             break;
 516           }
 517         } else
 518           addr.sin_addr = so->so_faddr;
 519         addr.sin_port = so->so_fport;
 520
 521         DEBUG_MISC((dfd, " sendto()ing, addr.sin_port=%d, addr.sin_addr.s_addr=%.16s\n", ntohs(addr.sin_port), inet_ntoa(addr.sin_addr)));
 522
 523         /* Don't care what port we get */
 524         ret = sendto(so->s, m->m_data, m->m_len, 0,
 525                      (struct sockaddr *)&addr, sizeof (struct sockaddr));
 526         if (ret < 0)
 527                 return -1;
 528
 529         /*
 530          * Kill the socket if there's no reply in 4 minutes,
 531          * but only if it's an expirable socket
 532          */
 533         if (so->so_expire)
 534                 so->so_expire = curtime + SO_EXPIRE;
 535         so->so_state = SS_ISFCONNECTED; /* So that it gets select()ed */
 536         return 0;
 537 }
 538
 539 /*
 540  * XXX This should really be tcp_listen
 541  */
 542 struct socket *
 543 solisten(port, laddr, lport, flags)
 544         u_int port;
 545         u_int32_t laddr;
 546         u_int lport;
 547         int flags;
 548 {
 549         struct sockaddr_in addr;
 550         struct socket *so;
 551         int s, opt = 1;
 552         socklen_t addrlen = sizeof(addr);
 553
 554         DEBUG_CALL("solisten");
 555         DEBUG_ARG("port = %d", port);
 556         DEBUG_ARG("laddr = %x", laddr);
 557         DEBUG_ARG("lport = %d", lport);
 558         DEBUG_ARG("flags = %x", flags);
 559
 560         if ((so = socreate()) == NULL) {
 561           /* free(so);      Not sofree() ??? free(NULL) == NOP */
 562           return NULL;
 563         }
 564
 565         /* Don't tcp_attach... we don't need so_snd nor so_rcv */
 566         if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {
 567                 free(so);
 568                 return NULL;
 569         }
 570         insque(so,&tcb);
 571
 572         /*
 573          * SS_FACCEPTONCE sockets must time out.
 574          */
 575         if (flags & SS_FACCEPTONCE)
 576            so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT*2;
 577
 578         so->so_state = (SS_FACCEPTCONN|flags);
 579         so->so_lport = lport; /* Kept in network format */
 580         so->so_laddr.s_addr = laddr; /* Ditto */
 581
 582         addr.sin_family = AF_INET;
 583         addr.sin_addr.s_addr = INADDR_ANY;
 584         addr.sin_port = port;
 585
 586         if (((s = socket(AF_INET,SOCK_STREAM,0)) < 0) ||
 587             (setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int)) < 0) ||
 588             (bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||
 589             (listen(s,1) < 0)) {
 590                 int tmperrno = errno; /* Don't clobber the real reason we failed */
 591
 592                 close(s);
 593                 sofree(so);
 594                 /* Restore the real errno */
 595 #ifdef _WIN32
 596                 WSASetLastError(tmperrno);
 597 #else
 598                 errno = tmperrno;
 599 #endif
 600                 return NULL;
 601         }
 602         setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));
 603
 604         getsockname(s,(struct sockaddr *)&addr,&addrlen);
 605         so->so_fport = addr.sin_port;
 606         if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
 607            so->so_faddr = alias_addr;
 608         else
 609            so->so_faddr = addr.sin_addr;
 610
 611         so->s = s;
 612         return so;
 613 }
 614
 615 #if 0
 616 /*
 617  * Data is available in so_rcv
 618  * Just write() the data to the socket
 619  * XXX not yet...
 620  */
 621 static void
 622 sorwakeup(so)
 623         struct socket *so;
 624 {
 625 /*      sowrite(so); */
 626 /*      FD_CLR(so->s,&writefds); */
 627 }
 628
 629 /*
 630  * Data has been freed in so_snd
 631  * We have room for a read() if we want to
 632  * For now, don't read, it'll be done in the main loop
 633  */
 634 static void
 635 sowwakeup(so)
 636         struct socket *so;
 637 {
 638         /* Nothing, yet */
 639 }
 640 #endif
 641
 642 /*
 643  * Various session state calls
 644  * XXX Should be #define's
 645  * The socket state stuff needs work, these often get call 2 or 3
 646  * times each when only 1 was needed
 647  */
 648 void
 649 soisfconnecting(so)
 650         register struct socket *so;
 651 {
 652         so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|
 653                           SS_FCANTSENDMORE|SS_FWDRAIN);
 654         so->so_state |= SS_ISFCONNECTING; /* Clobber other states */
 655 }
 656
 657 void
 658 soisfconnected(so)
 659         register struct socket *so;
 660 {
 661         so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
 662         so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
 663 }
 664
 665 static void
 666 sofcantrcvmore(struct socket *so)
 667 {
 668         if ((so->so_state & SS_NOFDREF) == 0) {
 669                 shutdown(so->s,0);
 670                 if(global_writefds) {
 671                   FD_CLR(so->s,global_writefds);
 672                 }
 673         }
 674         so->so_state &= ~(SS_ISFCONNECTING);
 675         if (so->so_state & SS_FCANTSENDMORE)
 676            so->so_state = SS_NOFDREF; /* Don't select it */ /* XXX close() here as well? */
 677         else
 678            so->so_state |= SS_FCANTRCVMORE;
 679 }
 680
 681 static void
 682 sofcantsendmore(struct socket *so)
 683 {
 684         if ((so->so_state & SS_NOFDREF) == 0) {
 685             shutdown(so->s,1);           /* send FIN to fhost */
 686             if (global_readfds) {
 687                 FD_CLR(so->s,global_readfds);
 688             }
 689             if (global_xfds) {
 690                 FD_CLR(so->s,global_xfds);
 691             }
 692         }
 693         so->so_state &= ~(SS_ISFCONNECTING);
 694         if (so->so_state & SS_FCANTRCVMORE)
 695            so->so_state = SS_NOFDREF; /* as above */
 696         else
 697            so->so_state |= SS_FCANTSENDMORE;
 698 }
 699
 700 void
 701 soisfdisconnected(so)
 702         struct socket *so;
 703 {
 704 /*      so->so_state &= ~(SS_ISFCONNECTING|SS_ISFCONNECTED); */
 705 /*      close(so->s); */
 706 /*      so->so_state = SS_ISFDISCONNECTED; */
 707         /*
 708          * XXX Do nothing ... ?
 709          */
 710 }
 711
 712 /*
 713  * Set write drain mode
 714  * Set CANTSENDMORE once all data has been write()n
 715  */
 716 void
 717 sofwdrain(so)
 718         struct socket *so;
 719 {
 720         if (so->so_rcv.sb_cc)
 721                 so->so_state |= SS_FWDRAIN;
 722         else
 723                 sofcantsendmore(so);
 724 }
 725