1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)uipc_socket2.c 7.17 (Berkeley) 5/4/91 34 * 35 * PATCHES MAGIC LEVEL PATCH THAT GOT US HERE 36 * -------------------- ----- ---------------------- 37 * CURRENT PATCH LEVEL: 1 00061 38 * -------------------- ----- ---------------------- 39 * 40 * 11 Dec 92 Williams Jolitz Fixed tty handling 41 */ 42 43 #include "param.h" 44 #include "systm.h" 45 #include "proc.h" 46 #include "file.h" 47 #include "buf.h" 48 #include "malloc.h" 49 #include "mbuf.h" 50 #include "protosw.h" 51 #include "socket.h" 52 #include "socketvar.h" 53 54 /* 55 * Primitive routines for operating on sockets and socket buffers 56 */ 57 58 /* strings for sleep message: */ 59 char netio[] = "netio"; 60 char netcon[] = "netcon"; 61 char netcls[] = "netcls"; 62 63 u_long sb_max = SB_MAX; /* patchable */ 64 65 /* 66 * Procedures to manipulate state flags of socket 67 * and do appropriate wakeups. Normal sequence from the 68 * active (originating) side is that soisconnecting() is 69 * called during processing of connect() call, 70 * resulting in an eventual call to soisconnected() if/when the 71 * connection is established. When the connection is torn down 72 * soisdisconnecting() is called during processing of disconnect() call, 73 * and soisdisconnected() is called when the connection to the peer 74 * is totally severed. The semantics of these routines are such that 75 * connectionless protocols can call soisconnected() and soisdisconnected() 76 * only, bypassing the in-progress calls when setting up a ``connection'' 77 * takes no time. 78 * 79 * From the passive side, a socket is created with 80 * two queues of sockets: so_q0 for connections in progress 81 * and so_q for connections already made and awaiting user acceptance. 82 * As a protocol is preparing incoming connections, it creates a socket 83 * structure queued on so_q0 by calling sonewconn(). When the connection 84 * is established, soisconnected() is called, and transfers the 85 * socket structure to so_q, making it available to accept(). 86 * 87 * If a socket is closed with sockets on either 88 * so_q0 or so_q, these sockets are dropped. 89 * 90 * If higher level protocols are implemented in 91 * the kernel, the wakeups done here will sometimes 92 * cause software-interrupt process scheduling. 93 */ 94 95 soisconnecting(so) 96 register struct socket *so; 97 { 98 99 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 100 so->so_state |= SS_ISCONNECTING; 101 } 102 103 soisconnected(so) 104 register struct socket *so; 105 { 106 register struct socket *head = so->so_head; 107 108 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 109 so->so_state |= SS_ISCONNECTED; 110 if (head && soqremque(so, 0)) { 111 soqinsque(head, so, 1); 112 sorwakeup(head); 113 wakeup((caddr_t)&head->so_timeo); 114 } else { 115 wakeup((caddr_t)&so->so_timeo); 116 sorwakeup(so); 117 sowwakeup(so); 118 } 119 } 120 121 soisdisconnecting(so) 122 register struct socket *so; 123 { 124 125 so->so_state &= ~SS_ISCONNECTING; 126 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); 127 wakeup((caddr_t)&so->so_timeo); 128 sowwakeup(so); 129 sorwakeup(so); 130 } 131 132 soisdisconnected(so) 133 register struct socket *so; 134 { 135 136 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 137 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE); 138 wakeup((caddr_t)&so->so_timeo); 139 sowwakeup(so); 140 sorwakeup(so); 141 } 142 143 /* 144 * When an attempt at a new connection is noted on a socket 145 * which accepts connections, sonewconn is called. If the 146 * connection is possible (subject to space constraints, etc.) 147 * then we allocate a new structure, propoerly linked into the 148 * data structure of the original socket, and return this. 149 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 150 * 151 * Currently, sonewconn() is defined as sonewconn1() in socketvar.h 152 * to catch calls that are missing the (new) second parameter. 153 */ 154 struct socket * 155 sonewconn1(head, connstatus) 156 register struct socket *head; 157 int connstatus; 158 { 159 register struct socket *so; 160 int soqueue = connstatus ? 1 : 0; 161 162 if (head->so_qlen + head->so_q0len > 3 * head->so_qlimit / 2) 163 return ((struct socket *)0); 164 MALLOC(so, struct socket *, sizeof(*so), M_SOCKET, M_DONTWAIT); 165 if (so == NULL) 166 return ((struct socket *)0); 167 bzero((caddr_t)so, sizeof(*so)); 168 so->so_type = head->so_type; 169 so->so_options = head->so_options &~ SO_ACCEPTCONN; 170 so->so_linger = head->so_linger; 171 so->so_state = head->so_state | SS_NOFDREF; 172 so->so_proto = head->so_proto; 173 so->so_timeo = head->so_timeo; 174 so->so_pgid = head->so_pgid; 175 (void) soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat); 176 soqinsque(head, so, soqueue); 177 if ((*so->so_proto->pr_usrreq)(so, PRU_ATTACH, 178 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0)) { 179 (void) soqremque(so, soqueue); 180 (void) free((caddr_t)so, M_SOCKET); 181 return ((struct socket *)0); 182 } 183 if (connstatus) { 184 sorwakeup(head); 185 wakeup((caddr_t)&head->so_timeo); 186 so->so_state |= connstatus; 187 } 188 return (so); 189 } 190 191 soqinsque(head, so, q) 192 register struct socket *head, *so; 193 int q; 194 { 195 196 register struct socket **prev; 197 so->so_head = head; 198 if (q == 0) { 199 head->so_q0len++; 200 so->so_q0 = 0; 201 for (prev = &(head->so_q0); *prev; ) 202 prev = &((*prev)->so_q0); 203 } else { 204 head->so_qlen++; 205 so->so_q = 0; 206 for (prev = &(head->so_q); *prev; ) 207 prev = &((*prev)->so_q); 208 } 209 *prev = so; 210 } 211 212 soqremque(so, q) 213 register struct socket *so; 214 int q; 215 { 216 register struct socket *head, *prev, *next; 217 218 head = so->so_head; 219 prev = head; 220 for (;;) { 221 next = q ? prev->so_q : prev->so_q0; 222 if (next == so) 223 break; 224 if (next == 0) 225 return (0); 226 prev = next; 227 } 228 if (q == 0) { 229 prev->so_q0 = next->so_q0; 230 head->so_q0len--; 231 } else { 232 prev->so_q = next->so_q; 233 head->so_qlen--; 234 } 235 next->so_q0 = next->so_q = 0; 236 next->so_head = 0; 237 return (1); 238 } 239 240 /* 241 * Socantsendmore indicates that no more data will be sent on the 242 * socket; it would normally be applied to a socket when the user 243 * informs the system that no more data is to be sent, by the protocol 244 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 245 * will be received, and will normally be applied to the socket by a 246 * protocol when it detects that the peer will send no more data. 247 * Data queued for reading in the socket may yet be read. 248 */ 249 250 socantsendmore(so) 251 struct socket *so; 252 { 253 254 so->so_state |= SS_CANTSENDMORE; 255 sowwakeup(so); 256 } 257 258 socantrcvmore(so) 259 struct socket *so; 260 { 261 262 so->so_state |= SS_CANTRCVMORE; 263 sorwakeup(so); 264 } 265 266 /* 267 * Socket select/wakeup routines. 268 */ 269 270 /* 271 * Queue a process for a select on a socket buffer. 272 */ 273 sbselqueue(sb, cp) 274 struct sockbuf *sb; 275 struct proc *cp; 276 { 277 struct proc *p; 278 279 if (sb->sb_sel && (p = pfind(sb->sb_sel)) && p->p_wchan == (caddr_t)&selwait) 280 sb->sb_flags |= SB_COLL; 281 else { 282 sb->sb_sel = cp->p_pid; 283 sb->sb_flags |= SB_SEL; 284 } 285 } 286 287 /* 288 * Wait for data to arrive at/drain from a socket buffer. 289 */ 290 sbwait(sb) 291 struct sockbuf *sb; 292 { 293 294 sb->sb_flags |= SB_WAIT; 295 return (tsleep((caddr_t)&sb->sb_cc, 296 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, netio, 297 sb->sb_timeo)); 298 } 299 300 /* 301 * Lock a sockbuf already known to be locked; 302 * return any error returned from sleep (EINTR). 303 */ 304 sb_lock(sb) 305 register struct sockbuf *sb; 306 { 307 int error; 308 309 while (sb->sb_flags & SB_LOCK) { 310 sb->sb_flags |= SB_WANT; 311 if (error = tsleep((caddr_t)&sb->sb_flags, 312 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK|PCATCH, 313 netio, 0)) 314 return (error); 315 } 316 sb->sb_flags |= SB_LOCK; 317 return (0); 318 } 319 320 /* 321 * Wakeup processes waiting on a socket buffer. 322 * Do asynchronous notification via SIGIO 323 * if the socket has the SS_ASYNC flag set. 324 */ 325 sowakeup(so, sb) 326 register struct socket *so; 327 register struct sockbuf *sb; 328 { 329 struct proc *p; 330 331 if (sb->sb_sel) { 332 selwakeup(sb->sb_sel, sb->sb_flags & SB_COLL); 333 sb->sb_sel = 0; 334 sb->sb_flags &= ~(SB_SEL|SB_COLL); 335 } 336 if (sb->sb_flags & SB_WAIT) { 337 sb->sb_flags &= ~SB_WAIT; 338 wakeup((caddr_t)&sb->sb_cc); 339 } 340 if (so->so_state & SS_ASYNC) { 341 if (so->so_pgid < 0) 342 gsignal(-so->so_pgid, SIGIO); 343 else if (so->so_pgid > 0 && (p = pfind(so->so_pgid)) != 0) 344 psignal(p, SIGIO); 345 } 346 } 347 348 /* 349 * Socket buffer (struct sockbuf) utility routines. 350 * 351 * Each socket contains two socket buffers: one for sending data and 352 * one for receiving data. Each buffer contains a queue of mbufs, 353 * information about the number of mbufs and amount of data in the 354 * queue, and other fields allowing select() statements and notification 355 * on data availability to be implemented. 356 * 357 * Data stored in a socket buffer is maintained as a list of records. 358 * Each record is a list of mbufs chained together with the m_next 359 * field. Records are chained together with the m_nextpkt field. The upper 360 * level routine soreceive() expects the following conventions to be 361 * observed when placing information in the receive buffer: 362 * 363 * 1. If the protocol requires each message be preceded by the sender's 364 * name, then a record containing that name must be present before 365 * any associated data (mbuf's must be of type MT_SONAME). 366 * 2. If the protocol supports the exchange of ``access rights'' (really 367 * just additional data associated with the message), and there are 368 * ``rights'' to be received, then a record containing this data 369 * should be present (mbuf's must be of type MT_RIGHTS). 370 * 3. If a name or rights record exists, then it must be followed by 371 * a data record, perhaps of zero length. 372 * 373 * Before using a new socket structure it is first necessary to reserve 374 * buffer space to the socket, by calling sbreserve(). This should commit 375 * some of the available buffer space in the system buffer pool for the 376 * socket (currently, it does nothing but enforce limits). The space 377 * should be released by calling sbrelease() when the socket is destroyed. 378 */ 379 380 soreserve(so, sndcc, rcvcc) 381 register struct socket *so; 382 u_long sndcc, rcvcc; 383 { 384 385 if (sbreserve(&so->so_snd, sndcc) == 0) 386 goto bad; 387 if (sbreserve(&so->so_rcv, rcvcc) == 0) 388 goto bad2; 389 if (so->so_rcv.sb_lowat == 0) 390 so->so_rcv.sb_lowat = 1; 391 if (so->so_snd.sb_lowat == 0) 392 so->so_snd.sb_lowat = MCLBYTES; 393 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 394 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 395 return (0); 396 bad2: 397 sbrelease(&so->so_snd); 398 bad: 399 return (ENOBUFS); 400 } 401 402 /* 403 * Allot mbufs to a sockbuf. 404 * Attempt to scale mbmax so that mbcnt doesn't become limiting 405 * if buffering efficiency is near the normal case. 406 */ 407 sbreserve(sb, cc) 408 struct sockbuf *sb; 409 u_long cc; 410 { 411 412 if (cc > sb_max * MCLBYTES / (MSIZE + MCLBYTES)) 413 return (0); 414 sb->sb_hiwat = cc; 415 sb->sb_mbmax = min(cc * 2, sb_max); 416 if (sb->sb_lowat > sb->sb_hiwat) 417 sb->sb_lowat = sb->sb_hiwat; 418 return (1); 419 } 420 421 /* 422 * Free mbufs held by a socket, and reserved mbuf space. 423 */ 424 sbrelease(sb) 425 struct sockbuf *sb; 426 { 427 428 sbflush(sb); 429 sb->sb_hiwat = sb->sb_mbmax = 0; 430 } 431 432 /* 433 * Routines to add and remove 434 * data from an mbuf queue. 435 * 436 * The routines sbappend() or sbappendrecord() are normally called to 437 * append new mbufs to a socket buffer, after checking that adequate 438 * space is available, comparing the function sbspace() with the amount 439 * of data to be added. sbappendrecord() differs from sbappend() in 440 * that data supplied is treated as the beginning of a new record. 441 * To place a sender's address, optional access rights, and data in a 442 * socket receive buffer, sbappendaddr() should be used. To place 443 * access rights and data in a socket receive buffer, sbappendrights() 444 * should be used. In either case, the new data begins a new record. 445 * Note that unlike sbappend() and sbappendrecord(), these routines check 446 * for the caller that there will be enough space to store the data. 447 * Each fails if there is not enough space, or if it cannot find mbufs 448 * to store additional information in. 449 * 450 * Reliable protocols may use the socket send buffer to hold data 451 * awaiting acknowledgement. Data is normally copied from a socket 452 * send buffer in a protocol with m_copy for output to a peer, 453 * and then removing the data from the socket buffer with sbdrop() 454 * or sbdroprecord() when the data is acknowledged by the peer. 455 */ 456 457 /* 458 * Append mbuf chain m to the last record in the 459 * socket buffer sb. The additional space associated 460 * the mbuf chain is recorded in sb. Empty mbufs are 461 * discarded and mbufs are compacted where possible. 462 */ 463 sbappend(sb, m) 464 struct sockbuf *sb; 465 struct mbuf *m; 466 { 467 register struct mbuf *n; 468 469 if (m == 0) 470 return; 471 if (n = sb->sb_mb) { 472 while (n->m_nextpkt) 473 n = n->m_nextpkt; 474 do { 475 if (n->m_flags & M_EOR) { 476 sbappendrecord(sb, m); /* XXXXXX!!!! */ 477 return; 478 } 479 } while (n->m_next && (n = n->m_next)); 480 } 481 sbcompress(sb, m, n); 482 } 483 484 #ifdef SOCKBUF_DEBUG 485 sbcheck(sb) 486 register struct sockbuf *sb; 487 { 488 register struct mbuf *m; 489 register int len = 0, mbcnt = 0; 490 491 for (m = sb->sb_mb; m; m = m->m_next) { 492 len += m->m_len; 493 mbcnt += MSIZE; 494 if (m->m_flags & M_EXT) 495 mbcnt += m->m_ext.ext_size; 496 if (m->m_nextpkt) 497 panic("sbcheck nextpkt"); 498 } 499 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 500 printf("cc %d != %d || mbcnt %d != %d\n", len, sb->sb_cc, 501 mbcnt, sb->sb_mbcnt); 502 panic("sbcheck"); 503 } 504 } 505 #endif 506 507 /* 508 * As above, except the mbuf chain 509 * begins a new record. 510 */ 511 sbappendrecord(sb, m0) 512 register struct sockbuf *sb; 513 register struct mbuf *m0; 514 { 515 register struct mbuf *m; 516 517 if (m0 == 0) 518 return; 519 if (m = sb->sb_mb) 520 while (m->m_nextpkt) 521 m = m->m_nextpkt; 522 /* 523 * Put the first mbuf on the queue. 524 * Note this permits zero length records. 525 */ 526 sballoc(sb, m0); 527 if (m) 528 m->m_nextpkt = m0; 529 else 530 sb->sb_mb = m0; 531 m = m0->m_next; 532 m0->m_next = 0; 533 if (m && (m0->m_flags & M_EOR)) { 534 m0->m_flags &= ~M_EOR; 535 m->m_flags |= M_EOR; 536 } 537 sbcompress(sb, m, m0); 538 } 539 540 /* 541 * As above except that OOB data 542 * is inserted at the beginning of the sockbuf, 543 * but after any other OOB data. 544 */ 545 sbinsertoob(sb, m0) 546 register struct sockbuf *sb; 547 register struct mbuf *m0; 548 { 549 register struct mbuf *m; 550 register struct mbuf **mp; 551 552 if (m0 == 0) 553 return; 554 for (mp = &sb->sb_mb; m = *mp; mp = &((*mp)->m_nextpkt)) { 555 again: 556 switch (m->m_type) { 557 558 case MT_OOBDATA: 559 continue; /* WANT next train */ 560 561 case MT_CONTROL: 562 if (m = m->m_next) 563 goto again; /* inspect THIS train further */ 564 } 565 break; 566 } 567 /* 568 * Put the first mbuf on the queue. 569 * Note this permits zero length records. 570 */ 571 sballoc(sb, m0); 572 m0->m_nextpkt = *mp; 573 *mp = m0; 574 m = m0->m_next; 575 m0->m_next = 0; 576 if (m && (m0->m_flags & M_EOR)) { 577 m0->m_flags &= ~M_EOR; 578 m->m_flags |= M_EOR; 579 } 580 sbcompress(sb, m, m0); 581 } 582 583 /* 584 * Append address and data, and optionally, control (ancillary) data 585 * to the receive queue of a socket. If present, 586 * m0 must include a packet header with total length. 587 * Returns 0 if no space in sockbuf or insufficient mbufs. 588 */ 589 sbappendaddr(sb, asa, m0, control) 590 register struct sockbuf *sb; 591 struct sockaddr *asa; 592 struct mbuf *m0, *control; 593 { 594 register struct mbuf *m, *n; 595 int space = asa->sa_len; 596 597 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 598 panic("sbappendaddr"); 599 if (m0) 600 space += m0->m_pkthdr.len; 601 for (n = control; n; n = n->m_next) { 602 space += n->m_len; 603 if (n->m_next == 0) /* keep pointer to last control buf */ 604 break; 605 } 606 if (space > sbspace(sb)) 607 return (0); 608 if (asa->sa_len > MLEN) 609 return (0); 610 MGET(m, M_DONTWAIT, MT_SONAME); 611 if (m == 0) 612 return (0); 613 m->m_len = asa->sa_len; 614 bcopy((caddr_t)asa, mtod(m, caddr_t), asa->sa_len); 615 if (n) 616 n->m_next = m0; /* concatenate data to control */ 617 else 618 control = m0; 619 m->m_next = control; 620 for (n = m; n; n = n->m_next) 621 sballoc(sb, n); 622 if (n = sb->sb_mb) { 623 while (n->m_nextpkt) 624 n = n->m_nextpkt; 625 n->m_nextpkt = m; 626 } else 627 sb->sb_mb = m; 628 return (1); 629 } 630 631 sbappendcontrol(sb, m0, control) 632 struct sockbuf *sb; 633 struct mbuf *control, *m0; 634 { 635 register struct mbuf *m, *n; 636 int space = 0; 637 638 if (control == 0) 639 panic("sbappendcontrol"); 640 for (m = control; ; m = m->m_next) { 641 space += m->m_len; 642 if (m->m_next == 0) 643 break; 644 } 645 n = m; /* save pointer to last control buffer */ 646 for (m = m0; m; m = m->m_next) 647 space += m->m_len; 648 if (space > sbspace(sb)) 649 return (0); 650 n->m_next = m0; /* concatenate data to control */ 651 for (m = control; m; m = m->m_next) 652 sballoc(sb, m); 653 if (n = sb->sb_mb) { 654 while (n->m_nextpkt) 655 n = n->m_nextpkt; 656 n->m_nextpkt = control; 657 } else 658 sb->sb_mb = control; 659 return (1); 660 } 661 662 /* 663 * Compress mbuf chain m into the socket 664 * buffer sb following mbuf n. If n 665 * is null, the buffer is presumed empty. 666 */ 667 sbcompress(sb, m, n) 668 register struct sockbuf *sb; 669 register struct mbuf *m, *n; 670 { 671 register int eor = 0; 672 register struct mbuf *o; 673 674 while (m) { 675 eor |= m->m_flags & M_EOR; 676 if (m->m_len == 0 && 677 (eor == 0 || 678 (((o = m->m_next) || (o = n)) && 679 o->m_type == m->m_type))) { 680 m = m_free(m); 681 continue; 682 } 683 if (n && (n->m_flags & (M_EXT | M_EOR)) == 0 && 684 (n->m_data + n->m_len + m->m_len) < &n->m_dat[MLEN] && 685 n->m_type == m->m_type) { 686 bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, 687 (unsigned)m->m_len); 688 n->m_len += m->m_len; 689 sb->sb_cc += m->m_len; 690 m = m_free(m); 691 continue; 692 } 693 if (n) 694 n->m_next = m; 695 else 696 sb->sb_mb = m; 697 sballoc(sb, m); 698 n = m; 699 m->m_flags &= ~M_EOR; 700 m = m->m_next; 701 n->m_next = 0; 702 } 703 if (eor) { 704 if (n) 705 n->m_flags |= eor; 706 else 707 printf("semi-panic: sbcompress\n"); 708 } 709 } 710 711 /* 712 * Free all mbufs in a sockbuf. 713 * Check that all resources are reclaimed. 714 */ 715 sbflush(sb) 716 register struct sockbuf *sb; 717 { 718 719 if (sb->sb_flags & SB_LOCK) 720 panic("sbflush"); 721 while (sb->sb_mbcnt) 722 sbdrop(sb, (int)sb->sb_cc); 723 if (sb->sb_cc || sb->sb_mb) 724 panic("sbflush 2"); 725 } 726 727 /* 728 * Drop data from (the front of) a sockbuf. 729 */ 730 sbdrop(sb, len) 731 register struct sockbuf *sb; 732 register int len; 733 { 734 register struct mbuf *m, *mn; 735 struct mbuf *next; 736 737 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 738 while (len > 0) { 739 if (m == 0) { 740 if (next == 0) 741 panic("sbdrop"); 742 m = next; 743 next = m->m_nextpkt; 744 continue; 745 } 746 if (m->m_len > len) { 747 m->m_len -= len; 748 m->m_data += len; 749 sb->sb_cc -= len; 750 break; 751 } 752 len -= m->m_len; 753 sbfree(sb, m); 754 MFREE(m, mn); 755 m = mn; 756 } 757 while (m && m->m_len == 0) { 758 sbfree(sb, m); 759 MFREE(m, mn); 760 m = mn; 761 } 762 if (m) { 763 sb->sb_mb = m; 764 m->m_nextpkt = next; 765 } else 766 sb->sb_mb = next; 767 } 768 769 /* 770 * Drop a record off the front of a sockbuf 771 * and move the next record to the front. 772 */ 773 sbdroprecord(sb) 774 register struct sockbuf *sb; 775 { 776 register struct mbuf *m, *mn; 777 778 m = sb->sb_mb; 779 if (m) { 780 sb->sb_mb = m->m_nextpkt; 781 do { 782 sbfree(sb, m); 783 MFREE(m, mn); 784 } while (m = mn); 785 } 786 } 787