sys_generic.c revision 1.27
1 /* $NetBSD: sys_generic.c,v 1.27 1996/09/05 15:32:52 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)sys_generic.c 8.5 (Berkeley) 1/21/94 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/filedesc.h> 46 #include <sys/ioctl.h> 47 #include <sys/file.h> 48 #include <sys/proc.h> 49 #include <sys/socketvar.h> 50 #include <sys/signalvar.h> 51 #include <sys/uio.h> 52 #include <sys/kernel.h> 53 #include <sys/stat.h> 54 #include <sys/malloc.h> 55 #ifdef KTRACE 56 #include <sys/ktrace.h> 57 #endif 58 59 #include <sys/mount.h> 60 #include <sys/syscallargs.h> 61 62 int selscan __P((struct proc *, fd_mask *, fd_mask *, int, register_t *)); 63 64 /* 65 * Read system call. 66 */ 67 /* ARGSUSED */ 68 int 69 sys_read(p, v, retval) 70 struct proc *p; 71 void *v; 72 register_t *retval; 73 { 74 register struct sys_read_args /* { 75 syscallarg(int) fd; 76 syscallarg(char *) buf; 77 syscallarg(u_int) nbyte; 78 } */ *uap = v; 79 register struct file *fp; 80 register struct filedesc *fdp = p->p_fd; 81 struct uio auio; 82 struct iovec aiov; 83 long cnt, error = 0; 84 #ifdef KTRACE 85 struct iovec ktriov; 86 #endif 87 88 if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles || 89 (fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL || 90 (fp->f_flag & FREAD) == 0) 91 return (EBADF); 92 aiov.iov_base = (caddr_t)SCARG(uap, buf); 93 aiov.iov_len = SCARG(uap, nbyte); 94 auio.uio_iov = &aiov; 95 auio.uio_iovcnt = 1; 96 auio.uio_resid = SCARG(uap, nbyte); 97 auio.uio_rw = UIO_READ; 98 auio.uio_segflg = UIO_USERSPACE; 99 auio.uio_procp = p; 100 if (auio.uio_resid < 0) 101 return EINVAL; 102 #ifdef KTRACE 103 /* 104 * if tracing, save a copy of iovec 105 */ 106 if (KTRPOINT(p, KTR_GENIO)) 107 ktriov = aiov; 108 #endif 109 cnt = SCARG(uap, nbyte); 110 error = (*fp->f_ops->fo_read)(fp, &auio, fp->f_cred); 111 if (error) 112 if (auio.uio_resid != cnt && (error == ERESTART || 113 error == EINTR || error == EWOULDBLOCK)) 114 error = 0; 115 cnt -= auio.uio_resid; 116 #ifdef KTRACE 117 if (KTRPOINT(p, KTR_GENIO) && error == 0) 118 ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_READ, &ktriov, 119 cnt, error); 120 #endif 121 *retval = cnt; 122 return (error); 123 } 124 125 /* 126 * Scatter read system call. 127 */ 128 int 129 sys_readv(p, v, retval) 130 struct proc *p; 131 void *v; 132 register_t *retval; 133 { 134 register struct sys_readv_args /* { 135 syscallarg(int) fd; 136 syscallarg(struct iovec *) iovp; 137 syscallarg(u_int) iovcnt; 138 } */ *uap = v; 139 register struct file *fp; 140 register struct filedesc *fdp = p->p_fd; 141 struct uio auio; 142 register struct iovec *iov; 143 struct iovec *needfree; 144 struct iovec aiov[UIO_SMALLIOV]; 145 long i, cnt, error = 0; 146 u_int iovlen; 147 #ifdef KTRACE 148 struct iovec *ktriov = NULL; 149 #endif 150 151 if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles || 152 (fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL || 153 (fp->f_flag & FREAD) == 0) 154 return (EBADF); 155 /* note: can't use iovlen until iovcnt is validated */ 156 iovlen = SCARG(uap, iovcnt) * sizeof (struct iovec); 157 if (SCARG(uap, iovcnt) > UIO_SMALLIOV) { 158 if (SCARG(uap, iovcnt) > UIO_MAXIOV) 159 return (EINVAL); 160 MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); 161 needfree = iov; 162 } else { 163 iov = aiov; 164 needfree = NULL; 165 } 166 auio.uio_iov = iov; 167 auio.uio_iovcnt = SCARG(uap, iovcnt); 168 auio.uio_rw = UIO_READ; 169 auio.uio_segflg = UIO_USERSPACE; 170 auio.uio_procp = p; 171 error = copyin((caddr_t)SCARG(uap, iovp), (caddr_t)iov, iovlen); 172 if (error) 173 goto done; 174 auio.uio_resid = 0; 175 for (i = 0; i < SCARG(uap, iovcnt); i++) { 176 #if 0 177 /* Cannot happen iov_len is unsigned */ 178 if (iov->iov_len < 0) { 179 error = EINVAL; 180 goto done; 181 } 182 #endif 183 auio.uio_resid += iov->iov_len; 184 if (auio.uio_resid < 0) { 185 error = EINVAL; 186 goto done; 187 } 188 iov++; 189 } 190 #ifdef KTRACE 191 /* 192 * if tracing, save a copy of iovec 193 */ 194 if (KTRPOINT(p, KTR_GENIO)) { 195 MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK); 196 bcopy((caddr_t)auio.uio_iov, (caddr_t)ktriov, iovlen); 197 } 198 #endif 199 cnt = auio.uio_resid; 200 error = (*fp->f_ops->fo_read)(fp, &auio, fp->f_cred); 201 if (error) 202 if (auio.uio_resid != cnt && (error == ERESTART || 203 error == EINTR || error == EWOULDBLOCK)) 204 error = 0; 205 cnt -= auio.uio_resid; 206 #ifdef KTRACE 207 if (ktriov != NULL) { 208 if (error == 0) 209 ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_READ, ktriov, 210 cnt, error); 211 FREE(ktriov, M_TEMP); 212 } 213 #endif 214 *retval = cnt; 215 done: 216 if (needfree) 217 FREE(needfree, M_IOV); 218 return (error); 219 } 220 221 /* 222 * Write system call 223 */ 224 int 225 sys_write(p, v, retval) 226 struct proc *p; 227 void *v; 228 register_t *retval; 229 { 230 register struct sys_write_args /* { 231 syscallarg(int) fd; 232 syscallarg(char *) buf; 233 syscallarg(u_int) nbyte; 234 } */ *uap = v; 235 register struct file *fp; 236 register struct filedesc *fdp = p->p_fd; 237 struct uio auio; 238 struct iovec aiov; 239 long cnt, error = 0; 240 #ifdef KTRACE 241 struct iovec ktriov; 242 #endif 243 244 if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles || 245 (fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL || 246 (fp->f_flag & FWRITE) == 0) 247 return (EBADF); 248 aiov.iov_base = (caddr_t)SCARG(uap, buf); 249 aiov.iov_len = SCARG(uap, nbyte); 250 auio.uio_iov = &aiov; 251 auio.uio_iovcnt = 1; 252 auio.uio_resid = SCARG(uap, nbyte); 253 auio.uio_rw = UIO_WRITE; 254 auio.uio_segflg = UIO_USERSPACE; 255 auio.uio_procp = p; 256 if (auio.uio_resid < 0) 257 return EINVAL; 258 #ifdef KTRACE 259 /* 260 * if tracing, save a copy of iovec 261 */ 262 if (KTRPOINT(p, KTR_GENIO)) 263 ktriov = aiov; 264 #endif 265 cnt = SCARG(uap, nbyte); 266 error = (*fp->f_ops->fo_write)(fp, &auio, fp->f_cred); 267 if (error) { 268 if (auio.uio_resid != cnt && (error == ERESTART || 269 error == EINTR || error == EWOULDBLOCK)) 270 error = 0; 271 if (error == EPIPE) 272 psignal(p, SIGPIPE); 273 } 274 cnt -= auio.uio_resid; 275 #ifdef KTRACE 276 if (KTRPOINT(p, KTR_GENIO) && error == 0) 277 ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_WRITE, 278 &ktriov, cnt, error); 279 #endif 280 *retval = cnt; 281 return (error); 282 } 283 284 /* 285 * Gather write system call 286 */ 287 int 288 sys_writev(p, v, retval) 289 struct proc *p; 290 void *v; 291 register_t *retval; 292 { 293 register struct sys_writev_args /* { 294 syscallarg(int) fd; 295 syscallarg(struct iovec *) iovp; 296 syscallarg(u_int) iovcnt; 297 } */ *uap = v; 298 register struct file *fp; 299 register struct filedesc *fdp = p->p_fd; 300 struct uio auio; 301 register struct iovec *iov; 302 struct iovec *needfree; 303 struct iovec aiov[UIO_SMALLIOV]; 304 long i, cnt, error = 0; 305 u_int iovlen; 306 #ifdef KTRACE 307 struct iovec *ktriov = NULL; 308 #endif 309 310 if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles || 311 (fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL || 312 (fp->f_flag & FWRITE) == 0) 313 return (EBADF); 314 /* note: can't use iovlen until iovcnt is validated */ 315 iovlen = SCARG(uap, iovcnt) * sizeof (struct iovec); 316 if (SCARG(uap, iovcnt) > UIO_SMALLIOV) { 317 if (SCARG(uap, iovcnt) > UIO_MAXIOV) 318 return (EINVAL); 319 MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK); 320 needfree = iov; 321 } else { 322 iov = aiov; 323 needfree = NULL; 324 } 325 auio.uio_iov = iov; 326 auio.uio_iovcnt = SCARG(uap, iovcnt); 327 auio.uio_rw = UIO_WRITE; 328 auio.uio_segflg = UIO_USERSPACE; 329 auio.uio_procp = p; 330 error = copyin((caddr_t)SCARG(uap, iovp), (caddr_t)iov, iovlen); 331 if (error) 332 goto done; 333 auio.uio_resid = 0; 334 for (i = 0; i < SCARG(uap, iovcnt); i++) { 335 #if 0 336 /* Cannot happen iov_len is unsigned */ 337 if (iov->iov_len < 0) { 338 error = EINVAL; 339 goto done; 340 } 341 #endif 342 auio.uio_resid += iov->iov_len; 343 if (auio.uio_resid < 0) { 344 error = EINVAL; 345 goto done; 346 } 347 iov++; 348 } 349 #ifdef KTRACE 350 /* 351 * if tracing, save a copy of iovec 352 */ 353 if (KTRPOINT(p, KTR_GENIO)) { 354 MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK); 355 bcopy((caddr_t)auio.uio_iov, (caddr_t)ktriov, iovlen); 356 } 357 #endif 358 cnt = auio.uio_resid; 359 error = (*fp->f_ops->fo_write)(fp, &auio, fp->f_cred); 360 if (error) { 361 if (auio.uio_resid != cnt && (error == ERESTART || 362 error == EINTR || error == EWOULDBLOCK)) 363 error = 0; 364 if (error == EPIPE) 365 psignal(p, SIGPIPE); 366 } 367 cnt -= auio.uio_resid; 368 #ifdef KTRACE 369 if (ktriov != NULL) { 370 if (error == 0) 371 ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_WRITE, 372 ktriov, cnt, error); 373 FREE(ktriov, M_TEMP); 374 } 375 #endif 376 *retval = cnt; 377 done: 378 if (needfree) 379 FREE(needfree, M_IOV); 380 return (error); 381 } 382 383 /* 384 * Ioctl system call 385 */ 386 /* ARGSUSED */ 387 int 388 sys_ioctl(p, v, retval) 389 struct proc *p; 390 void *v; 391 register_t *retval; 392 { 393 register struct sys_ioctl_args /* { 394 syscallarg(int) fd; 395 syscallarg(u_long) com; 396 syscallarg(caddr_t) data; 397 } */ *uap = v; 398 register struct file *fp; 399 register struct filedesc *fdp; 400 register u_long com; 401 register int error; 402 register u_int size; 403 caddr_t data, memp; 404 int tmp; 405 #define STK_PARAMS 128 406 char stkbuf[STK_PARAMS]; 407 408 fdp = p->p_fd; 409 if ((u_int)SCARG(uap, fd) >= fdp->fd_nfiles || 410 (fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL) 411 return (EBADF); 412 413 if ((fp->f_flag & (FREAD | FWRITE)) == 0) 414 return (EBADF); 415 416 switch (com = SCARG(uap, com)) { 417 case FIONCLEX: 418 fdp->fd_ofileflags[SCARG(uap, fd)] &= ~UF_EXCLOSE; 419 return (0); 420 case FIOCLEX: 421 fdp->fd_ofileflags[SCARG(uap, fd)] |= UF_EXCLOSE; 422 return (0); 423 } 424 425 /* 426 * Interpret high order word to find amount of data to be 427 * copied to/from the user's address space. 428 */ 429 size = IOCPARM_LEN(com); 430 if (size > IOCPARM_MAX) 431 return (ENOTTY); 432 memp = NULL; 433 if (size > sizeof (stkbuf)) { 434 memp = (caddr_t)malloc((u_long)size, M_IOCTLOPS, M_WAITOK); 435 data = memp; 436 } else 437 data = stkbuf; 438 if (com&IOC_IN) { 439 if (size) { 440 error = copyin(SCARG(uap, data), data, (u_int)size); 441 if (error) { 442 if (memp) 443 free(memp, M_IOCTLOPS); 444 return (error); 445 } 446 } else 447 *(caddr_t *)data = SCARG(uap, data); 448 } else if ((com&IOC_OUT) && size) 449 /* 450 * Zero the buffer so the user always 451 * gets back something deterministic. 452 */ 453 bzero(data, size); 454 else if (com&IOC_VOID) 455 *(caddr_t *)data = SCARG(uap, data); 456 457 switch (com) { 458 459 case FIONBIO: 460 if ((tmp = *(int *)data) != 0) 461 fp->f_flag |= FNONBLOCK; 462 else 463 fp->f_flag &= ~FNONBLOCK; 464 error = (*fp->f_ops->fo_ioctl)(fp, FIONBIO, (caddr_t)&tmp, p); 465 break; 466 467 case FIOASYNC: 468 if ((tmp = *(int *)data) != 0) 469 fp->f_flag |= FASYNC; 470 else 471 fp->f_flag &= ~FASYNC; 472 error = (*fp->f_ops->fo_ioctl)(fp, FIOASYNC, (caddr_t)&tmp, p); 473 break; 474 475 case FIOSETOWN: 476 tmp = *(int *)data; 477 if (fp->f_type == DTYPE_SOCKET) { 478 ((struct socket *)fp->f_data)->so_pgid = tmp; 479 error = 0; 480 break; 481 } 482 if (tmp <= 0) { 483 tmp = -tmp; 484 } else { 485 struct proc *p1 = pfind(tmp); 486 if (p1 == 0) { 487 error = ESRCH; 488 break; 489 } 490 tmp = p1->p_pgrp->pg_id; 491 } 492 error = (*fp->f_ops->fo_ioctl) 493 (fp, TIOCSPGRP, (caddr_t)&tmp, p); 494 break; 495 496 case FIOGETOWN: 497 if (fp->f_type == DTYPE_SOCKET) { 498 error = 0; 499 *(int *)data = ((struct socket *)fp->f_data)->so_pgid; 500 break; 501 } 502 error = (*fp->f_ops->fo_ioctl)(fp, TIOCGPGRP, data, p); 503 *(int *)data = -*(int *)data; 504 break; 505 506 default: 507 error = (*fp->f_ops->fo_ioctl)(fp, com, data, p); 508 /* 509 * Copy any data to user, size was 510 * already set and checked above. 511 */ 512 if (error == 0 && (com&IOC_OUT) && size) 513 error = copyout(data, SCARG(uap, data), (u_int)size); 514 break; 515 } 516 if (memp) 517 free(memp, M_IOCTLOPS); 518 return (error); 519 } 520 521 int selwait, nselcoll; 522 523 /* 524 * Select system call. 525 */ 526 int 527 sys_select(p, v, retval) 528 register struct proc *p; 529 void *v; 530 register_t *retval; 531 { 532 register struct sys_select_args /* { 533 syscallarg(u_int) nd; 534 syscallarg(fd_set *) in; 535 syscallarg(fd_set *) ou; 536 syscallarg(fd_set *) ex; 537 syscallarg(struct timeval *) tv; 538 } */ *uap = v; 539 caddr_t bits; 540 char smallbits[howmany(FD_SETSIZE, NFDBITS) * sizeof(fd_mask) * 6]; 541 struct timeval atv; 542 int s, ncoll, error = 0, timo; 543 size_t ni; 544 545 if (SCARG(uap, nd) > p->p_fd->fd_nfiles) { 546 /* forgiving; slightly wrong */ 547 SCARG(uap, nd) = p->p_fd->fd_nfiles; 548 } 549 ni = howmany(SCARG(uap, nd), NFDBITS) * sizeof(fd_mask); 550 if (ni * 6 > sizeof(smallbits)) 551 bits = malloc(ni * 6, M_TEMP, M_WAITOK); 552 else 553 bits = smallbits; 554 555 #define getbits(name, x) \ 556 if (SCARG(uap, name)) { \ 557 error = copyin((caddr_t)SCARG(uap, name), bits + ni * x, ni); \ 558 if (error) \ 559 goto done; \ 560 } else \ 561 bzero(bits + ni * x, ni); 562 getbits(in, 0); 563 getbits(ou, 1); 564 getbits(ex, 2); 565 #undef getbits 566 567 if (SCARG(uap, tv)) { 568 error = copyin((caddr_t)SCARG(uap, tv), (caddr_t)&atv, 569 sizeof (atv)); 570 if (error) 571 goto done; 572 if (itimerfix(&atv)) { 573 error = EINVAL; 574 goto done; 575 } 576 s = splclock(); 577 timeradd(&atv, &time, &atv); 578 timo = hzto(&atv); 579 /* 580 * Avoid inadvertently sleeping forever. 581 */ 582 if (timo == 0) 583 timo = 1; 584 splx(s); 585 } else 586 timo = 0; 587 retry: 588 ncoll = nselcoll; 589 p->p_flag |= P_SELECT; 590 error = selscan(p, (fd_mask *)(bits + ni * 0), 591 (fd_mask *)(bits + ni * 3), SCARG(uap, nd), retval); 592 if (error || *retval) 593 goto done; 594 s = splhigh(); 595 if (timo && timercmp(&time, &atv, >=)) { 596 splx(s); 597 goto done; 598 } 599 if ((p->p_flag & P_SELECT) == 0 || nselcoll != ncoll) { 600 splx(s); 601 goto retry; 602 } 603 p->p_flag &= ~P_SELECT; 604 error = tsleep((caddr_t)&selwait, PSOCK | PCATCH, "select", timo); 605 splx(s); 606 if (error == 0) 607 goto retry; 608 done: 609 p->p_flag &= ~P_SELECT; 610 /* select is not restarted after signals... */ 611 if (error == ERESTART) 612 error = EINTR; 613 if (error == EWOULDBLOCK) 614 error = 0; 615 if (error == 0) { 616 #define putbits(name, x) \ 617 if (SCARG(uap, name)) { \ 618 error = copyout(bits + ni * x, (caddr_t)SCARG(uap, name), ni); \ 619 if (error) \ 620 goto out; \ 621 } 622 putbits(in, 3); 623 putbits(ou, 4); 624 putbits(ex, 5); 625 #undef putbits 626 } 627 out: 628 if (ni * 6 > sizeof(smallbits)) 629 free(bits, M_TEMP); 630 return (error); 631 } 632 633 int 634 selscan(p, ibitp, obitp, nfd, retval) 635 struct proc *p; 636 fd_mask *ibitp, *obitp; 637 int nfd; 638 register_t *retval; 639 { 640 register struct filedesc *fdp = p->p_fd; 641 register int msk, i, j, fd; 642 register fd_mask ibits, obits; 643 struct file *fp; 644 int n = 0; 645 static int flag[3] = { FREAD, FWRITE, 0 }; 646 647 for (msk = 0; msk < 3; msk++) { 648 for (i = 0; i < nfd; i += NFDBITS) { 649 ibits = *ibitp++; 650 obits = 0; 651 while ((j = ffs(ibits)) && (fd = i + --j) < nfd) { 652 ibits &= ~(1 << j); 653 fp = fdp->fd_ofiles[fd]; 654 if (fp == NULL) 655 return (EBADF); 656 if ((*fp->f_ops->fo_select)(fp, flag[msk], p)) { 657 obits |= (1 << j); 658 n++; 659 } 660 } 661 *obitp++ = obits; 662 } 663 } 664 *retval = n; 665 return (0); 666 } 667 668 /*ARGSUSED*/ 669 int 670 seltrue(dev, flag, p) 671 dev_t dev; 672 int flag; 673 struct proc *p; 674 { 675 676 return (1); 677 } 678 679 /* 680 * Record a select request. 681 */ 682 void 683 selrecord(selector, sip) 684 struct proc *selector; 685 struct selinfo *sip; 686 { 687 struct proc *p; 688 pid_t mypid; 689 690 mypid = selector->p_pid; 691 if (sip->si_pid == mypid) 692 return; 693 if (sip->si_pid && (p = pfind(sip->si_pid)) && 694 p->p_wchan == (caddr_t)&selwait) 695 sip->si_flags |= SI_COLL; 696 else 697 sip->si_pid = mypid; 698 } 699 700 /* 701 * Do a wakeup when a selectable event occurs. 702 */ 703 void 704 selwakeup(sip) 705 register struct selinfo *sip; 706 { 707 register struct proc *p; 708 int s; 709 710 if (sip->si_pid == 0) 711 return; 712 if (sip->si_flags & SI_COLL) { 713 nselcoll++; 714 sip->si_flags &= ~SI_COLL; 715 wakeup((caddr_t)&selwait); 716 } 717 p = pfind(sip->si_pid); 718 sip->si_pid = 0; 719 if (p != NULL) { 720 s = splhigh(); 721 if (p->p_wchan == (caddr_t)&selwait) { 722 if (p->p_stat == SSLEEP) 723 setrunnable(p); 724 else 725 unsleep(p); 726 } else if (p->p_flag & P_SELECT) 727 p->p_flag &= ~P_SELECT; 728 splx(s); 729 } 730 } 731
Indexes created Tue Sep 23 07:09:52 GMT 2025