1 /* $NetBSD: uipc_socket2.c,v 1.36 2000/03/30 09:27:14 augustss Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)uipc_socket2.c 8.2 (Berkeley) 2/14/95 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/proc.h> 41 #include <sys/file.h> 42 #include <sys/buf.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/protosw.h> 46 #include <sys/socket.h> 47 #include <sys/socketvar.h> 48 #include <sys/signalvar.h> 49 50 /* 51 * Primitive routines for operating on sockets and socket buffers 52 */ 53 54 /* strings for sleep message: */ 55 const char netio[] = "netio"; 56 const char netcon[] = "netcon"; 57 const char netcls[] = "netcls"; 58 59 /* 60 * Procedures to manipulate state flags of socket 61 * and do appropriate wakeups. Normal sequence from the 62 * active (originating) side is that soisconnecting() is 63 * called during processing of connect() call, 64 * resulting in an eventual call to soisconnected() if/when the 65 * connection is established. When the connection is torn down 66 * soisdisconnecting() is called during processing of disconnect() call, 67 * and soisdisconnected() is called when the connection to the peer 68 * is totally severed. The semantics of these routines are such that 69 * connectionless protocols can call soisconnected() and soisdisconnected() 70 * only, bypassing the in-progress calls when setting up a ``connection'' 71 * takes no time. 72 * 73 * From the passive side, a socket is created with 74 * two queues of sockets: so_q0 for connections in progress 75 * and so_q for connections already made and awaiting user acceptance. 76 * As a protocol is preparing incoming connections, it creates a socket 77 * structure queued on so_q0 by calling sonewconn(). When the connection 78 * is established, soisconnected() is called, and transfers the 79 * socket structure to so_q, making it available to accept(). 80 * 81 * If a socket is closed with sockets on either 82 * so_q0 or so_q, these sockets are dropped. 83 * 84 * If higher level protocols are implemented in 85 * the kernel, the wakeups done here will sometimes 86 * cause software-interrupt process scheduling. 87 */ 88 89 void 90 soisconnecting(so) 91 struct socket *so; 92 { 93 94 so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); 95 so->so_state |= SS_ISCONNECTING; 96 } 97 98 void 99 soisconnected(so) 100 struct socket *so; 101 { 102 struct socket *head = so->so_head; 103 104 so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); 105 so->so_state |= SS_ISCONNECTED; 106 if (head && soqremque(so, 0)) { 107 soqinsque(head, so, 1); 108 sorwakeup(head); 109 wakeup((caddr_t)&head->so_timeo); 110 } else { 111 wakeup((caddr_t)&so->so_timeo); 112 sorwakeup(so); 113 sowwakeup(so); 114 } 115 } 116 117 void 118 soisdisconnecting(so) 119 struct socket *so; 120 { 121 122 so->so_state &= ~SS_ISCONNECTING; 123 so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); 124 wakeup((caddr_t)&so->so_timeo); 125 sowwakeup(so); 126 sorwakeup(so); 127 } 128 129 void 130 soisdisconnected(so) 131 struct socket *so; 132 { 133 134 so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); 135 so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED); 136 wakeup((caddr_t)&so->so_timeo); 137 sowwakeup(so); 138 sorwakeup(so); 139 } 140 141 /* 142 * When an attempt at a new connection is noted on a socket 143 * which accepts connections, sonewconn is called. If the 144 * connection is possible (subject to space constraints, etc.) 145 * then we allocate a new structure, propoerly linked into the 146 * data structure of the original socket, and return this. 147 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 148 * 149 * Currently, sonewconn() is defined as sonewconn1() in socketvar.h 150 * to catch calls that are missing the (new) second parameter. 151 */ 152 struct socket * 153 sonewconn1(head, connstatus) 154 struct socket *head; 155 int connstatus; 156 { 157 struct socket *so; 158 int soqueue = connstatus ? 1 : 0; 159 160 if (head->so_qlen + head->so_q0len > 3 * head->so_qlimit / 2) 161 return ((struct socket *)0); 162 so = pool_get(&socket_pool, PR_NOWAIT); 163 if (so == NULL) 164 return (NULL); 165 memset((caddr_t)so, 0, sizeof(*so)); 166 so->so_type = head->so_type; 167 so->so_options = head->so_options &~ SO_ACCEPTCONN; 168 so->so_linger = head->so_linger; 169 so->so_state = head->so_state | SS_NOFDREF; 170 so->so_proto = head->so_proto; 171 so->so_timeo = head->so_timeo; 172 so->so_pgid = head->so_pgid; 173 so->so_send = head->so_send; 174 so->so_receive = head->so_receive; 175 so->so_uid = head->so_uid; 176 (void) soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat); 177 soqinsque(head, so, soqueue); 178 if ((*so->so_proto->pr_usrreq)(so, PRU_ATTACH, 179 (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, 180 (struct proc *)0)) { 181 (void) soqremque(so, soqueue); 182 pool_put(&socket_pool, so); 183 return (NULL); 184 } 185 if (connstatus) { 186 sorwakeup(head); 187 wakeup((caddr_t)&head->so_timeo); 188 so->so_state |= connstatus; 189 } 190 return (so); 191 } 192 193 void 194 soqinsque(head, so, q) 195 struct socket *head, *so; 196 int q; 197 { 198 199 #ifdef DIAGNOSTIC 200 if (so->so_onq != NULL) 201 panic("soqinsque"); 202 #endif 203 204 so->so_head = head; 205 if (q == 0) { 206 head->so_q0len++; 207 so->so_onq = &head->so_q0; 208 } else { 209 head->so_qlen++; 210 so->so_onq = &head->so_q; 211 } 212 TAILQ_INSERT_TAIL(so->so_onq, so, so_qe); 213 } 214 215 int 216 soqremque(so, q) 217 struct socket *so; 218 int q; 219 { 220 struct socket *head = so->so_head; 221 222 if (q == 0) { 223 if (so->so_onq != &head->so_q0) 224 return (0); 225 head->so_q0len--; 226 } else { 227 if (so->so_onq != &head->so_q) 228 return (0); 229 head->so_qlen--; 230 } 231 TAILQ_REMOVE(so->so_onq, so, so_qe); 232 so->so_onq = NULL; 233 so->so_head = NULL; 234 return (1); 235 } 236 237 /* 238 * Socantsendmore indicates that no more data will be sent on the 239 * socket; it would normally be applied to a socket when the user 240 * informs the system that no more data is to be sent, by the protocol 241 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 242 * will be received, and will normally be applied to the socket by a 243 * protocol when it detects that the peer will send no more data. 244 * Data queued for reading in the socket may yet be read. 245 */ 246 247 void 248 socantsendmore(so) 249 struct socket *so; 250 { 251 252 so->so_state |= SS_CANTSENDMORE; 253 sowwakeup(so); 254 } 255 256 void 257 socantrcvmore(so) 258 struct socket *so; 259 { 260 261 so->so_state |= SS_CANTRCVMORE; 262 sorwakeup(so); 263 } 264 265 /* 266 * Wait for data to arrive at/drain from a socket buffer. 267 */ 268 int 269 sbwait(sb) 270 struct sockbuf *sb; 271 { 272 273 sb->sb_flags |= SB_WAIT; 274 return (tsleep((caddr_t)&sb->sb_cc, 275 (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, netio, 276 sb->sb_timeo)); 277 } 278 279 /* 280 * Lock a sockbuf already known to be locked; 281 * return any error returned from sleep (EINTR). 282 */ 283 int 284 sb_lock(sb) 285 struct sockbuf *sb; 286 { 287 int error; 288 289 while (sb->sb_flags & SB_LOCK) { 290 sb->sb_flags |= SB_WANT; 291 error = tsleep((caddr_t)&sb->sb_flags, 292 (sb->sb_flags & SB_NOINTR) ? 293 PSOCK : PSOCK|PCATCH, netio, 0); 294 if (error) 295 return (error); 296 } 297 sb->sb_flags |= SB_LOCK; 298 return (0); 299 } 300 301 /* 302 * Wakeup processes waiting on a socket buffer. 303 * Do asynchronous notification via SIGIO 304 * if the socket has the SS_ASYNC flag set. 305 */ 306 void 307 sowakeup(so, sb) 308 struct socket *so; 309 struct sockbuf *sb; 310 { 311 struct proc *p; 312 313 selwakeup(&sb->sb_sel); 314 sb->sb_flags &= ~SB_SEL; 315 if (sb->sb_flags & SB_WAIT) { 316 sb->sb_flags &= ~SB_WAIT; 317 wakeup((caddr_t)&sb->sb_cc); 318 } 319 if (so->so_state & SS_ASYNC) { 320 if (so->so_pgid < 0) 321 gsignal(-so->so_pgid, SIGIO); 322 else if (so->so_pgid > 0 && (p = pfind(so->so_pgid)) != 0) 323 psignal(p, SIGIO); 324 } 325 if (sb->sb_flags & SB_UPCALL) 326 (*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT); 327 } 328 329 /* 330 * Socket buffer (struct sockbuf) utility routines. 331 * 332 * Each socket contains two socket buffers: one for sending data and 333 * one for receiving data. Each buffer contains a queue of mbufs, 334 * information about the number of mbufs and amount of data in the 335 * queue, and other fields allowing poll() statements and notification 336 * on data availability to be implemented. 337 * 338 * Data stored in a socket buffer is maintained as a list of records. 339 * Each record is a list of mbufs chained together with the m_next 340 * field. Records are chained together with the m_nextpkt field. The upper 341 * level routine soreceive() expects the following conventions to be 342 * observed when placing information in the receive buffer: 343 * 344 * 1. If the protocol requires each message be preceded by the sender's 345 * name, then a record containing that name must be present before 346 * any associated data (mbuf's must be of type MT_SONAME). 347 * 2. If the protocol supports the exchange of ``access rights'' (really 348 * just additional data associated with the message), and there are 349 * ``rights'' to be received, then a record containing this data 350 * should be present (mbuf's must be of type MT_CONTROL). 351 * 3. If a name or rights record exists, then it must be followed by 352 * a data record, perhaps of zero length. 353 * 354 * Before using a new socket structure it is first necessary to reserve 355 * buffer space to the socket, by calling sbreserve(). This should commit 356 * some of the available buffer space in the system buffer pool for the 357 * socket (currently, it does nothing but enforce limits). The space 358 * should be released by calling sbrelease() when the socket is destroyed. 359 */ 360 361 int 362 soreserve(so, sndcc, rcvcc) 363 struct socket *so; 364 u_long sndcc, rcvcc; 365 { 366 367 if (sbreserve(&so->so_snd, sndcc) == 0) 368 goto bad; 369 if (sbreserve(&so->so_rcv, rcvcc) == 0) 370 goto bad2; 371 if (so->so_rcv.sb_lowat == 0) 372 so->so_rcv.sb_lowat = 1; 373 if (so->so_snd.sb_lowat == 0) 374 so->so_snd.sb_lowat = MCLBYTES; 375 if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat) 376 so->so_snd.sb_lowat = so->so_snd.sb_hiwat; 377 return (0); 378 bad2: 379 sbrelease(&so->so_snd); 380 bad: 381 return (ENOBUFS); 382 } 383 384 /* 385 * Allot mbufs to a sockbuf. 386 * Attempt to scale mbmax so that mbcnt doesn't become limiting 387 * if buffering efficiency is near the normal case. 388 */ 389 int 390 sbreserve(sb, cc) 391 struct sockbuf *sb; 392 u_long cc; 393 { 394 395 if (cc == 0 || cc > sb_max * MCLBYTES / (MSIZE + MCLBYTES)) 396 return (0); 397 sb->sb_hiwat = cc; 398 sb->sb_mbmax = min(cc * 2, sb_max); 399 if (sb->sb_lowat > sb->sb_hiwat) 400 sb->sb_lowat = sb->sb_hiwat; 401 return (1); 402 } 403 404 /* 405 * Free mbufs held by a socket, and reserved mbuf space. 406 */ 407 void 408 sbrelease(sb) 409 struct sockbuf *sb; 410 { 411 412 sbflush(sb); 413 sb->sb_hiwat = sb->sb_mbmax = 0; 414 } 415 416 /* 417 * Routines to add and remove 418 * data from an mbuf queue. 419 * 420 * The routines sbappend() or sbappendrecord() are normally called to 421 * append new mbufs to a socket buffer, after checking that adequate 422 * space is available, comparing the function sbspace() with the amount 423 * of data to be added. sbappendrecord() differs from sbappend() in 424 * that data supplied is treated as the beginning of a new record. 425 * To place a sender's address, optional access rights, and data in a 426 * socket receive buffer, sbappendaddr() should be used. To place 427 * access rights and data in a socket receive buffer, sbappendrights() 428 * should be used. In either case, the new data begins a new record. 429 * Note that unlike sbappend() and sbappendrecord(), these routines check 430 * for the caller that there will be enough space to store the data. 431 * Each fails if there is not enough space, or if it cannot find mbufs 432 * to store additional information in. 433 * 434 * Reliable protocols may use the socket send buffer to hold data 435 * awaiting acknowledgement. Data is normally copied from a socket 436 * send buffer in a protocol with m_copy for output to a peer, 437 * and then removing the data from the socket buffer with sbdrop() 438 * or sbdroprecord() when the data is acknowledged by the peer. 439 */ 440 441 /* 442 * Append mbuf chain m to the last record in the 443 * socket buffer sb. The additional space associated 444 * the mbuf chain is recorded in sb. Empty mbufs are 445 * discarded and mbufs are compacted where possible. 446 */ 447 void 448 sbappend(sb, m) 449 struct sockbuf *sb; 450 struct mbuf *m; 451 { 452 struct mbuf *n; 453 454 if (m == 0) 455 return; 456 if ((n = sb->sb_mb) != NULL) { 457 while (n->m_nextpkt) 458 n = n->m_nextpkt; 459 do { 460 if (n->m_flags & M_EOR) { 461 sbappendrecord(sb, m); /* XXXXXX!!!! */ 462 return; 463 } 464 } while (n->m_next && (n = n->m_next)); 465 } 466 sbcompress(sb, m, n); 467 } 468 469 #ifdef SOCKBUF_DEBUG 470 void 471 sbcheck(sb) 472 struct sockbuf *sb; 473 { 474 struct mbuf *m; 475 int len = 0, mbcnt = 0; 476 477 for (m = sb->sb_mb; m; m = m->m_next) { 478 len += m->m_len; 479 mbcnt += MSIZE; 480 if (m->m_flags & M_EXT) 481 mbcnt += m->m_ext.ext_size; 482 if (m->m_nextpkt) 483 panic("sbcheck nextpkt"); 484 } 485 if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) { 486 printf("cc %d != %d || mbcnt %d != %d\n", len, sb->sb_cc, 487 mbcnt, sb->sb_mbcnt); 488 panic("sbcheck"); 489 } 490 } 491 #endif 492 493 /* 494 * As above, except the mbuf chain 495 * begins a new record. 496 */ 497 void 498 sbappendrecord(sb, m0) 499 struct sockbuf *sb; 500 struct mbuf *m0; 501 { 502 struct mbuf *m; 503 504 if (m0 == 0) 505 return; 506 if ((m = sb->sb_mb) != NULL) 507 while (m->m_nextpkt) 508 m = m->m_nextpkt; 509 /* 510 * Put the first mbuf on the queue. 511 * Note this permits zero length records. 512 */ 513 sballoc(sb, m0); 514 if (m) 515 m->m_nextpkt = m0; 516 else 517 sb->sb_mb = m0; 518 m = m0->m_next; 519 m0->m_next = 0; 520 if (m && (m0->m_flags & M_EOR)) { 521 m0->m_flags &= ~M_EOR; 522 m->m_flags |= M_EOR; 523 } 524 sbcompress(sb, m, m0); 525 } 526 527 /* 528 * As above except that OOB data 529 * is inserted at the beginning of the sockbuf, 530 * but after any other OOB data. 531 */ 532 void 533 sbinsertoob(sb, m0) 534 struct sockbuf *sb; 535 struct mbuf *m0; 536 { 537 struct mbuf *m; 538 struct mbuf **mp; 539 540 if (m0 == 0) 541 return; 542 for (mp = &sb->sb_mb; (m = *mp) != NULL; mp = &((*mp)->m_nextpkt)) { 543 again: 544 switch (m->m_type) { 545 546 case MT_OOBDATA: 547 continue; /* WANT next train */ 548 549 case MT_CONTROL: 550 if ((m = m->m_next) != NULL) 551 goto again; /* inspect THIS train further */ 552 } 553 break; 554 } 555 /* 556 * Put the first mbuf on the queue. 557 * Note this permits zero length records. 558 */ 559 sballoc(sb, m0); 560 m0->m_nextpkt = *mp; 561 *mp = m0; 562 m = m0->m_next; 563 m0->m_next = 0; 564 if (m && (m0->m_flags & M_EOR)) { 565 m0->m_flags &= ~M_EOR; 566 m->m_flags |= M_EOR; 567 } 568 sbcompress(sb, m, m0); 569 } 570 571 /* 572 * Append address and data, and optionally, control (ancillary) data 573 * to the receive queue of a socket. If present, 574 * m0 must include a packet header with total length. 575 * Returns 0 if no space in sockbuf or insufficient mbufs. 576 */ 577 int 578 sbappendaddr(sb, asa, m0, control) 579 struct sockbuf *sb; 580 struct sockaddr *asa; 581 struct mbuf *m0, *control; 582 { 583 struct mbuf *m, *n; 584 int space = asa->sa_len; 585 586 if (m0 && (m0->m_flags & M_PKTHDR) == 0) 587 panic("sbappendaddr"); 588 if (m0) 589 space += m0->m_pkthdr.len; 590 for (n = control; n; n = n->m_next) { 591 space += n->m_len; 592 if (n->m_next == 0) /* keep pointer to last control buf */ 593 break; 594 } 595 if (space > sbspace(sb)) 596 return (0); 597 MGET(m, M_DONTWAIT, MT_SONAME); 598 if (m == 0) 599 return (0); 600 if (asa->sa_len > MLEN) { 601 MEXTMALLOC(m, asa->sa_len, M_NOWAIT); 602 if ((m->m_flags & M_EXT) == 0) { 603 m_free(m); 604 return (0); 605 } 606 } 607 m->m_len = asa->sa_len; 608 memcpy(mtod(m, caddr_t), (caddr_t)asa, asa->sa_len); 609 if (n) 610 n->m_next = m0; /* concatenate data to control */ 611 else 612 control = m0; 613 m->m_next = control; 614 for (n = m; n; n = n->m_next) 615 sballoc(sb, n); 616 if ((n = sb->sb_mb) != NULL) { 617 while (n->m_nextpkt) 618 n = n->m_nextpkt; 619 n->m_nextpkt = m; 620 } else 621 sb->sb_mb = m; 622 return (1); 623 } 624 625 int 626 sbappendcontrol(sb, m0, control) 627 struct sockbuf *sb; 628 struct mbuf *m0, *control; 629 { 630 struct mbuf *m, *n; 631 int space = 0; 632 633 if (control == 0) 634 panic("sbappendcontrol"); 635 for (m = control; ; m = m->m_next) { 636 space += m->m_len; 637 if (m->m_next == 0) 638 break; 639 } 640 n = m; /* save pointer to last control buffer */ 641 for (m = m0; m; m = m->m_next) 642 space += m->m_len; 643 if (space > sbspace(sb)) 644 return (0); 645 n->m_next = m0; /* concatenate data to control */ 646 for (m = control; m; m = m->m_next) 647 sballoc(sb, m); 648 if ((n = sb->sb_mb) != NULL) { 649 while (n->m_nextpkt) 650 n = n->m_nextpkt; 651 n->m_nextpkt = control; 652 } else 653 sb->sb_mb = control; 654 return (1); 655 } 656 657 /* 658 * Compress mbuf chain m into the socket 659 * buffer sb following mbuf n. If n 660 * is null, the buffer is presumed empty. 661 */ 662 void 663 sbcompress(sb, m, n) 664 struct sockbuf *sb; 665 struct mbuf *m, *n; 666 { 667 int eor = 0; 668 struct mbuf *o; 669 670 while (m) { 671 eor |= m->m_flags & M_EOR; 672 if (m->m_len == 0 && 673 (eor == 0 || 674 (((o = m->m_next) || (o = n)) && 675 o->m_type == m->m_type))) { 676 m = m_free(m); 677 continue; 678 } 679 if (n && (n->m_flags & M_EOR) == 0 && n->m_type == m->m_type && 680 (((n->m_flags & M_EXT) == 0 && 681 n->m_data + n->m_len + m->m_len <= &n->m_dat[MLEN]) || 682 ((~n->m_flags & (M_EXT|M_CLUSTER)) == 0 && 683 !MCLISREFERENCED(n) && 684 n->m_data + n->m_len + m->m_len <= &n->m_ext.ext_buf[MCLBYTES]))) { 685 memcpy(mtod(n, caddr_t) + n->m_len, mtod(m, caddr_t), 686 (unsigned)m->m_len); 687 n->m_len += m->m_len; 688 sb->sb_cc += m->m_len; 689 m = m_free(m); 690 continue; 691 } 692 if (n) 693 n->m_next = m; 694 else 695 sb->sb_mb = m; 696 sballoc(sb, m); 697 n = m; 698 m->m_flags &= ~M_EOR; 699 m = m->m_next; 700 n->m_next = 0; 701 } 702 if (eor) { 703 if (n) 704 n->m_flags |= eor; 705 else 706 printf("semi-panic: sbcompress\n"); 707 } 708 } 709 710 /* 711 * Free all mbufs in a sockbuf. 712 * Check that all resources are reclaimed. 713 */ 714 void 715 sbflush(sb) 716 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 void 731 sbdrop(sb, len) 732 struct sockbuf *sb; 733 int len; 734 { 735 struct mbuf *m, *mn; 736 struct mbuf *next; 737 738 next = (m = sb->sb_mb) ? m->m_nextpkt : 0; 739 while (len > 0) { 740 if (m == 0) { 741 if (next == 0) 742 panic("sbdrop"); 743 m = next; 744 next = m->m_nextpkt; 745 continue; 746 } 747 if (m->m_len > len) { 748 m->m_len -= len; 749 m->m_data += len; 750 sb->sb_cc -= len; 751 break; 752 } 753 len -= m->m_len; 754 sbfree(sb, m); 755 MFREE(m, mn); 756 m = mn; 757 } 758 while (m && m->m_len == 0) { 759 sbfree(sb, m); 760 MFREE(m, mn); 761 m = mn; 762 } 763 if (m) { 764 sb->sb_mb = m; 765 m->m_nextpkt = next; 766 } else 767 sb->sb_mb = next; 768 } 769 770 /* 771 * Drop a record off the front of a sockbuf 772 * and move the next record to the front. 773 */ 774 void 775 sbdroprecord(sb) 776 struct sockbuf *sb; 777 { 778 struct mbuf *m, *mn; 779 780 m = sb->sb_mb; 781 if (m) { 782 sb->sb_mb = m->m_nextpkt; 783 do { 784 sbfree(sb, m); 785 MFREE(m, mn); 786 } while ((m = mn) != NULL); 787 } 788 } 789 790 /* 791 * Create a "control" mbuf containing the specified data 792 * with the specified type for presentation on a socket buffer. 793 */ 794 struct mbuf * 795 sbcreatecontrol(p, size, type, level) 796 caddr_t p; 797 int size; 798 int type, level; 799 { 800 struct cmsghdr *cp; 801 struct mbuf *m; 802 803 if (CMSG_SPACE(size) > MCLBYTES) { 804 printf("sbcreatecontrol: message too large %d\n", size); 805 return NULL; 806 } 807 808 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 809 return ((struct mbuf *) NULL); 810 if (CMSG_SPACE(size) > MLEN) { 811 MCLGET(m, M_DONTWAIT); 812 if ((m->m_flags & M_EXT) == 0) { 813 m_free(m); 814 return NULL; 815 } 816 } 817 cp = mtod(m, struct cmsghdr *); 818 memcpy(CMSG_DATA(cp), p, size); 819 m->m_len = CMSG_SPACE(size); 820 cp->cmsg_len = CMSG_LEN(size); 821 cp->cmsg_level = level; 822 cp->cmsg_type = type; 823 return (m); 824 } 825