redir.c revision 1.63
1 /* $NetBSD: redir.c,v 1.63 2019/02/09 03:35:55 kre Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)redir.c 8.2 (Berkeley) 5/4/95"; 39 #else 40 __RCSID("$NetBSD: redir.c,v 1.63 2019/02/09 03:35:55 kre Exp $"); 41 #endif 42 #endif /* not lint */ 43 44 #include <sys/types.h> 45 #include <sys/param.h> /* PIPE_BUF */ 46 #include <sys/stat.h> 47 #include <signal.h> 48 #include <string.h> 49 #include <fcntl.h> 50 #include <errno.h> 51 #include <unistd.h> 52 #include <stdlib.h> 53 54 /* 55 * Code for dealing with input/output redirection. 56 */ 57 58 #include "main.h" 59 #include "builtins.h" 60 #include "shell.h" 61 #include "nodes.h" 62 #include "jobs.h" 63 #include "options.h" 64 #include "expand.h" 65 #include "redir.h" 66 #include "output.h" 67 #include "memalloc.h" 68 #include "mystring.h" 69 #include "error.h" 70 #include "show.h" 71 72 73 #define EMPTY -2 /* marks an unused slot in redirtab */ 74 #define CLOSED -1 /* fd was not open before redir */ 75 #ifndef PIPE_BUF 76 # define PIPESIZE 4096 /* amount of buffering in a pipe */ 77 #else 78 # define PIPESIZE PIPE_BUF 79 #endif 80 81 82 MKINIT 83 struct renamelist { 84 struct renamelist *next; 85 int orig; 86 int into; 87 }; 88 89 MKINIT 90 struct redirtab { 91 struct redirtab *next; 92 struct renamelist *renamed; 93 }; 94 95 96 MKINIT struct redirtab *redirlist; 97 98 /* 99 * We keep track of whether or not fd0 has been redirected. This is for 100 * background commands, where we want to redirect fd0 to /dev/null only 101 * if it hasn't already been redirected. 102 */ 103 STATIC int fd0_redirected = 0; 104 105 /* 106 * And also where to put internal use fds that should be out of the 107 * way of user defined fds (normally) 108 */ 109 STATIC int big_sh_fd = 0; 110 111 STATIC const struct renamelist *is_renamed(const struct renamelist *, int); 112 STATIC void fd_rename(struct redirtab *, int, int); 113 STATIC void free_rl(struct redirtab *, int); 114 STATIC void openredirect(union node *, char[10], int); 115 STATIC int openhere(const union node *); 116 STATIC int copyfd(int, int, int); 117 STATIC void find_big_fd(void); 118 119 120 struct shell_fds { /* keep track of internal shell fds */ 121 struct shell_fds *nxt; 122 void (*cb)(int, int); 123 int fd; 124 }; 125 126 STATIC struct shell_fds *sh_fd_list; 127 128 STATIC void renumber_sh_fd(struct shell_fds *); 129 STATIC struct shell_fds *sh_fd(int); 130 131 STATIC const struct renamelist * 132 is_renamed(const struct renamelist *rl, int fd) 133 { 134 while (rl != NULL) { 135 if (rl->orig == fd) 136 return rl; 137 rl = rl->next; 138 } 139 return NULL; 140 } 141 142 STATIC void 143 free_rl(struct redirtab *rt, int reset) 144 { 145 struct renamelist *rl, *rn = rt->renamed; 146 147 while ((rl = rn) != NULL) { 148 rn = rl->next; 149 if (rl->orig == 0) 150 fd0_redirected--; 151 VTRACE(DBG_REDIR, ("popredir %d%s: %s", 152 rl->orig, rl->orig==0 ? " (STDIN)" : "", 153 reset ? "" : "no reset\n")); 154 if (reset) { 155 if (rl->into < 0) { 156 VTRACE(DBG_REDIR, ("closed\n")); 157 close(rl->orig); 158 } else { 159 VTRACE(DBG_REDIR, ("from %d\n", rl->into)); 160 movefd(rl->into, rl->orig); 161 } 162 } 163 ckfree(rl); 164 } 165 rt->renamed = NULL; 166 } 167 168 STATIC void 169 fd_rename(struct redirtab *rt, int from, int to) 170 { 171 /* XXX someday keep a short list (8..10) of freed renamelists XXX */ 172 struct renamelist *rl = ckmalloc(sizeof(struct renamelist)); 173 174 rl->next = rt->renamed; 175 rt->renamed = rl; 176 177 rl->orig = from; 178 rl->into = to; 179 } 180 181 /* 182 * Process a list of redirection commands. If the REDIR_PUSH flag is set, 183 * old file descriptors are stashed away so that the redirection can be 184 * undone by calling popredir. If the REDIR_BACKQ flag is set, then the 185 * standard output, and the standard error if it becomes a duplicate of 186 * stdout, is saved in memory. 187 */ 188 189 void 190 redirect(union node *redir, int flags) 191 { 192 union node *n; 193 struct redirtab *sv = NULL; 194 int i; 195 int fd; 196 char memory[10]; /* file descriptors to write to memory */ 197 198 CTRACE(DBG_REDIR, ("redirect(F=0x%x):%s\n", flags, redir?"":" NONE")); 199 for (i = 10 ; --i >= 0 ; ) 200 memory[i] = 0; 201 memory[1] = flags & REDIR_BACKQ; 202 if (flags & REDIR_PUSH) { 203 /* 204 * We don't have to worry about REDIR_VFORK here, as 205 * flags & REDIR_PUSH is never true if REDIR_VFORK is set. 206 */ 207 sv = ckmalloc(sizeof (struct redirtab)); 208 sv->renamed = NULL; 209 sv->next = redirlist; 210 redirlist = sv; 211 } 212 for (n = redir ; n ; n = n->nfile.next) { 213 fd = n->nfile.fd; 214 VTRACE(DBG_REDIR, ("redir %d (max=%d) ", fd, max_user_fd)); 215 if (fd > max_user_fd) 216 max_user_fd = fd; 217 renumber_sh_fd(sh_fd(fd)); 218 if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) && 219 n->ndup.dupfd == fd) { 220 /* redirect from/to same file descriptor */ 221 /* make sure it stays open */ 222 if (fcntl(fd, F_SETFD, 0) < 0) 223 error("fd %d: %s", fd, strerror(errno)); 224 VTRACE(DBG_REDIR, ("!cloexec\n")); 225 continue; 226 } 227 228 if ((flags & REDIR_PUSH) && !is_renamed(sv->renamed, fd)) { 229 INTOFF; 230 if (big_sh_fd < 10) 231 find_big_fd(); 232 if ((i = fcntl(fd, F_DUPFD, big_sh_fd)) == -1) { 233 switch (errno) { 234 case EBADF: 235 i = CLOSED; 236 break; 237 case EMFILE: 238 case EINVAL: 239 find_big_fd(); 240 i = fcntl(fd, F_DUPFD, big_sh_fd); 241 if (i >= 0) 242 break; 243 /* FALLTHRU */ 244 default: 245 i = errno; 246 error("%d: %s", fd, strerror(i)); 247 /* NOTREACHED */ 248 } 249 } 250 if (i >= 0) 251 (void)fcntl(i, F_SETFD, FD_CLOEXEC); 252 fd_rename(sv, fd, i); 253 VTRACE(DBG_REDIR, ("saved as %d ", i)); 254 INTON; 255 } 256 VTRACE(DBG_REDIR, ("%s\n", fd == 0 ? "STDIN" : "")); 257 if (fd == 0) 258 fd0_redirected++; 259 openredirect(n, memory, flags); 260 } 261 if (memory[1]) 262 out1 = &memout; 263 if (memory[2]) 264 out2 = &memout; 265 } 266 267 268 STATIC void 269 openredirect(union node *redir, char memory[10], int flags) 270 { 271 struct stat sb; 272 int fd = redir->nfile.fd; 273 char *fname; 274 int f; 275 int eflags, cloexec; 276 277 /* 278 * We suppress interrupts so that we won't leave open file 279 * descriptors around. This may not be such a good idea because 280 * an open of a device or a fifo can block indefinitely. 281 */ 282 INTOFF; 283 if (fd < 10) 284 memory[fd] = 0; 285 switch (redir->nfile.type) { 286 case NFROM: 287 fname = redir->nfile.expfname; 288 if (flags & REDIR_VFORK) 289 eflags = O_NONBLOCK; 290 else 291 eflags = 0; 292 if ((f = open(fname, O_RDONLY|eflags)) < 0) 293 goto eopen; 294 VTRACE(DBG_REDIR, ("openredirect(< '%s') -> %d [%#x]", 295 fname, f, eflags)); 296 if (eflags) 297 (void)fcntl(f, F_SETFL, fcntl(f, F_GETFL, 0) & ~eflags); 298 break; 299 case NFROMTO: 300 fname = redir->nfile.expfname; 301 if ((f = open(fname, O_RDWR|O_CREAT, 0666)) < 0) 302 goto ecreate; 303 VTRACE(DBG_REDIR, ("openredirect(<> '%s') -> %d", fname, f)); 304 break; 305 case NTO: 306 if (Cflag) { 307 fname = redir->nfile.expfname; 308 if ((f = open(fname, O_WRONLY)) == -1) { 309 if ((f = open(fname, O_WRONLY|O_CREAT|O_EXCL, 310 0666)) < 0) 311 goto ecreate; 312 } else if (fstat(f, &sb) == -1) { 313 int serrno = errno; 314 close(f); 315 errno = serrno; 316 goto ecreate; 317 } else if (S_ISREG(sb.st_mode)) { 318 close(f); 319 errno = EEXIST; 320 goto ecreate; 321 } 322 VTRACE(DBG_REDIR, ("openredirect(>| '%s') -> %d", 323 fname, f)); 324 break; 325 } 326 /* FALLTHROUGH */ 327 case NCLOBBER: 328 fname = redir->nfile.expfname; 329 if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0) 330 goto ecreate; 331 VTRACE(DBG_REDIR, ("openredirect(> '%s') -> %d", fname, f)); 332 break; 333 case NAPPEND: 334 fname = redir->nfile.expfname; 335 if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0) 336 goto ecreate; 337 VTRACE(DBG_REDIR, ("openredirect(>> '%s') -> %d", fname, f)); 338 break; 339 case NTOFD: 340 case NFROMFD: 341 if (redir->ndup.dupfd >= 0) { /* if not ">&-" */ 342 if (fd < 10 && redir->ndup.dupfd < 10 && 343 memory[redir->ndup.dupfd]) 344 memory[fd] = 1; 345 else if (copyfd(redir->ndup.dupfd, fd, 346 (flags & REDIR_KEEP) == 0) < 0) 347 error("Redirect (from %d to %d) failed: %s", 348 redir->ndup.dupfd, fd, strerror(errno)); 349 VTRACE(DBG_REDIR, ("openredirect: %d%c&%d\n", fd, 350 "<>"[redir->nfile.type==NTOFD], redir->ndup.dupfd)); 351 } else { 352 (void) close(fd); 353 VTRACE(DBG_REDIR, ("openredirect: %d%c&-\n", fd, 354 "<>"[redir->nfile.type==NTOFD])); 355 } 356 INTON; 357 return; 358 case NHERE: 359 case NXHERE: 360 VTRACE(DBG_REDIR, ("openredirect: %d<<...", fd)); 361 f = openhere(redir); 362 break; 363 default: 364 abort(); 365 } 366 367 cloexec = fd > 2 && (flags & REDIR_KEEP) == 0 && !posix; 368 if (f != fd) { 369 VTRACE(DBG_REDIR, (" -> %d", fd)); 370 if (copyfd(f, fd, cloexec) < 0) { 371 int e = errno; 372 373 close(f); 374 error("redirect reassignment (fd %d) failed: %s", fd, 375 strerror(e)); 376 } 377 close(f); 378 } else if (cloexec) 379 (void)fcntl(f, F_SETFD, FD_CLOEXEC); 380 VTRACE(DBG_REDIR, ("%s\n", cloexec ? " cloexec" : "")); 381 382 INTON; 383 return; 384 ecreate: 385 exerrno = 1; 386 error("cannot create %s: %s", fname, errmsg(errno, E_CREAT)); 387 eopen: 388 exerrno = 1; 389 error("cannot open %s: %s", fname, errmsg(errno, E_OPEN)); 390 } 391 392 393 /* 394 * Handle here documents. Normally we fork off a process to write the 395 * data to a pipe. If the document is short, we can stuff the data in 396 * the pipe without forking. 397 */ 398 399 STATIC int 400 openhere(const union node *redir) 401 { 402 int pip[2]; 403 int len = 0; 404 405 if (pipe(pip) < 0) 406 error("Pipe call failed"); 407 if (redir->type == NHERE) { 408 len = strlen(redir->nhere.doc->narg.text); 409 if (len <= PIPESIZE) { 410 xwrite(pip[1], redir->nhere.doc->narg.text, len); 411 goto out; 412 } 413 } 414 VTRACE(DBG_REDIR, (" forking [%d,%d]\n", pip[0], pip[1])); 415 if (forkshell(NULL, NULL, FORK_NOJOB) == 0) { 416 close(pip[0]); 417 signal(SIGINT, SIG_IGN); 418 signal(SIGQUIT, SIG_IGN); 419 signal(SIGHUP, SIG_IGN); 420 #ifdef SIGTSTP 421 signal(SIGTSTP, SIG_IGN); 422 #endif 423 signal(SIGPIPE, SIG_DFL); 424 if (redir->type == NHERE) 425 xwrite(pip[1], redir->nhere.doc->narg.text, len); 426 else 427 expandhere(redir->nhere.doc, pip[1]); 428 _exit(0); 429 } 430 VTRACE(DBG_REDIR, ("openhere (closing %d)", pip[1])); 431 out: 432 close(pip[1]); 433 VTRACE(DBG_REDIR, (" (pipe fd=%d)", pip[0])); 434 return pip[0]; 435 } 436 437 438 439 /* 440 * Undo the effects of the last redirection. 441 */ 442 443 void 444 popredir(void) 445 { 446 struct redirtab *rp = redirlist; 447 448 INTOFF; 449 free_rl(rp, 1); 450 redirlist = rp->next; 451 ckfree(rp); 452 INTON; 453 } 454 455 /* 456 * Undo all redirections. Called on error or interrupt. 457 */ 458 459 #ifdef mkinit 460 461 INCLUDE "redir.h" 462 463 RESET { 464 while (redirlist) 465 popredir(); 466 } 467 468 SHELLPROC { 469 clearredir(0); 470 } 471 472 #endif 473 474 /* Return true if fd 0 has already been redirected at least once. */ 475 int 476 fd0_redirected_p(void) 477 { 478 return fd0_redirected != 0; 479 } 480 481 /* 482 * Discard all saved file descriptors. 483 */ 484 485 void 486 clearredir(int vforked) 487 { 488 struct redirtab *rp; 489 struct renamelist *rl; 490 491 for (rp = redirlist ; rp ; rp = rp->next) { 492 if (!vforked) 493 free_rl(rp, 0); 494 else for (rl = rp->renamed; rl; rl = rl->next) 495 if (rl->into >= 0) 496 close(rl->into); 497 } 498 } 499 500 501 502 /* 503 * Copy a file descriptor to be == to. 504 * cloexec indicates if we want close-on-exec or not. 505 * Returns -1 if any error occurs. 506 */ 507 508 STATIC int 509 copyfd(int from, int to, int cloexec) 510 { 511 int newfd; 512 513 if (cloexec && to > 2) 514 newfd = dup3(from, to, O_CLOEXEC); 515 else 516 newfd = dup2(from, to); 517 518 return newfd; 519 } 520 521 /* 522 * rename fd from to be fd to (closing from). 523 * close-on-exec is never set on 'to' (unless 524 * from==to and it was set on from) - ie: a no-op 525 * returns to (or errors() if an error occurs). 526 * 527 * This is mostly used for rearranging the 528 * results from pipe(). 529 */ 530 int 531 movefd(int from, int to) 532 { 533 if (from == to) 534 return to; 535 536 (void) close(to); 537 if (copyfd(from, to, 0) != to) { 538 int e = errno; 539 540 (void) close(from); 541 error("Unable to make fd %d: %s", to, strerror(e)); 542 } 543 (void) close(from); 544 545 return to; 546 } 547 548 STATIC void 549 find_big_fd(void) 550 { 551 int i, fd; 552 static int last_start = 3; /* aim to keep sh fd's under 20 */ 553 554 if (last_start < 10) 555 last_start++; 556 557 for (i = (1 << last_start); i >= 10; i >>= 1) { 558 if ((fd = fcntl(0, F_DUPFD, i - 1)) >= 0) { 559 close(fd); 560 break; 561 } 562 } 563 564 fd = (i / 5) * 4; 565 if (fd < 10) 566 fd = 10; 567 568 big_sh_fd = fd; 569 } 570 571 /* 572 * If possible, move file descriptor fd out of the way 573 * of expected user fd values. Returns the new fd 574 * (which may be the input fd if things do not go well.) 575 * Always set close-on-exec on the result, and close 576 * the input fd unless it is to be our result. 577 */ 578 int 579 to_upper_fd(int fd) 580 { 581 int i; 582 583 VTRACE(DBG_REDIR|DBG_OUTPUT, ("to_upper_fd(%d)", fd)); 584 if (big_sh_fd < 10) 585 find_big_fd(); 586 do { 587 i = fcntl(fd, F_DUPFD_CLOEXEC, big_sh_fd); 588 if (i >= 0) { 589 if (fd != i) 590 close(fd); 591 VTRACE(DBG_REDIR|DBG_OUTPUT, ("-> %d\n", i)); 592 return i; 593 } 594 if (errno != EMFILE && errno != EINVAL) 595 break; 596 find_big_fd(); 597 } while (big_sh_fd > 10); 598 599 /* 600 * If we wanted to move this fd to some random high number 601 * we certainly do not intend to pass it through exec, even 602 * if the reassignment failed. 603 */ 604 (void)fcntl(fd, F_SETFD, FD_CLOEXEC); 605 VTRACE(DBG_REDIR|DBG_OUTPUT, (" fails ->%d\n", fd)); 606 return fd; 607 } 608 609 void 610 register_sh_fd(int fd, void (*cb)(int, int)) 611 { 612 struct shell_fds *fp; 613 614 fp = ckmalloc(sizeof (struct shell_fds)); 615 if (fp != NULL) { 616 fp->nxt = sh_fd_list; 617 sh_fd_list = fp; 618 619 fp->fd = fd; 620 fp->cb = cb; 621 } 622 } 623 624 void 625 sh_close(int fd) 626 { 627 struct shell_fds **fpp, *fp; 628 629 fpp = &sh_fd_list; 630 while ((fp = *fpp) != NULL) { 631 if (fp->fd == fd) { 632 *fpp = fp->nxt; 633 ckfree(fp); 634 break; 635 } 636 fpp = &fp->nxt; 637 } 638 (void)close(fd); 639 } 640 641 STATIC struct shell_fds * 642 sh_fd(int fd) 643 { 644 struct shell_fds *fp; 645 646 for (fp = sh_fd_list; fp != NULL; fp = fp->nxt) 647 if (fp->fd == fd) 648 return fp; 649 return NULL; 650 } 651 652 STATIC void 653 renumber_sh_fd(struct shell_fds *fp) 654 { 655 int to; 656 657 if (fp == NULL) 658 return; 659 660 #ifndef F_DUPFD_CLOEXEC 661 #define F_DUPFD_CLOEXEC F_DUPFD 662 #define CLOEXEC(fd) (fcntl((fd), F_SETFD, fcntl((fd),F_GETFD) | FD_CLOEXEC)) 663 #else 664 #define CLOEXEC(fd) 665 #endif 666 667 /* 668 * if we have had a collision, and the sh fd was a "big" one 669 * try moving the sh fd base to a higher number (if possible) 670 * so future sh fds are less likely to be in the user's sights 671 * (incl this one when moved) 672 */ 673 if (fp->fd >= big_sh_fd) 674 find_big_fd(); 675 676 to = fcntl(fp->fd, F_DUPFD_CLOEXEC, big_sh_fd); 677 if (to == -1) 678 to = fcntl(fp->fd, F_DUPFD_CLOEXEC, big_sh_fd/2); 679 if (to == -1) 680 to = fcntl(fp->fd, F_DUPFD_CLOEXEC, fp->fd + 1); 681 if (to == -1) 682 to = fcntl(fp->fd, F_DUPFD_CLOEXEC, 10); 683 if (to == -1) 684 to = fcntl(fp->fd, F_DUPFD_CLOEXEC, 3); 685 if (to == -1) 686 error("insufficient file descriptors available"); 687 CLOEXEC(to); 688 689 if (fp->fd == to) /* impossible? */ 690 return; 691 692 (*fp->cb)(fp->fd, to); 693 (void)close(fp->fd); 694 fp->fd = to; 695 } 696 697 static const struct flgnames { 698 const char *name; 699 uint16_t minch; 700 uint32_t value; 701 } nv[] = { 702 #ifdef O_APPEND 703 { "append", 2, O_APPEND }, 704 #endif 705 #ifdef O_ASYNC 706 { "async", 2, O_ASYNC }, 707 #endif 708 #ifdef O_SYNC 709 { "sync", 2, O_SYNC }, 710 #endif 711 #ifdef O_NONBLOCK 712 { "nonblock", 3, O_NONBLOCK }, 713 #endif 714 #ifdef O_FSYNC 715 { "fsync", 2, O_FSYNC }, 716 #endif 717 #ifdef O_DSYNC 718 { "dsync", 2, O_DSYNC }, 719 #endif 720 #ifdef O_RSYNC 721 { "rsync", 2, O_RSYNC }, 722 #endif 723 #ifdef O_ALT_IO 724 { "altio", 2, O_ALT_IO }, 725 #endif 726 #ifdef O_DIRECT 727 { "direct", 2, O_DIRECT }, 728 #endif 729 #ifdef O_NOSIGPIPE 730 { "nosigpipe", 3, O_NOSIGPIPE }, 731 #endif 732 #ifdef O_CLOEXEC 733 { "cloexec", 2, O_CLOEXEC }, 734 #endif 735 { 0, 0, 0 } 736 }; 737 #define ALLFLAGS (O_APPEND|O_ASYNC|O_SYNC|O_NONBLOCK|O_DSYNC|O_RSYNC|\ 738 O_ALT_IO|O_DIRECT|O_NOSIGPIPE|O_CLOEXEC) 739 740 static int 741 getflags(int fd, int p) 742 { 743 int c, f; 744 745 if (sh_fd(fd) != NULL) { 746 if (!p) 747 return -1; 748 error("Can't get status for fd=%d (%s)", fd, 749 "Bad file descriptor"); /*XXX*/ 750 } 751 752 if ((c = fcntl(fd, F_GETFD)) == -1) { 753 if (!p) 754 return -1; 755 error("Can't get status for fd=%d (%s)", fd, strerror(errno)); 756 } 757 if ((f = fcntl(fd, F_GETFL)) == -1) { 758 if (!p) 759 return -1; 760 error("Can't get flags for fd=%d (%s)", fd, strerror(errno)); 761 } 762 if (c & FD_CLOEXEC) 763 f |= O_CLOEXEC; 764 return f & ALLFLAGS; 765 } 766 767 static void 768 printone(int fd, int p, int verbose, int pfd) 769 { 770 int f = getflags(fd, p); 771 const struct flgnames *fn; 772 773 if (f == -1) 774 return; 775 776 if (pfd) 777 outfmt(out1, "%d: ", fd); 778 for (fn = nv; fn->name; fn++) { 779 if (f & fn->value) { 780 outfmt(out1, "%s%s", verbose ? "+" : "", fn->name); 781 f &= ~fn->value; 782 } else if (verbose) 783 outfmt(out1, "-%s", fn->name); 784 else 785 continue; 786 if (f || (verbose && fn[1].name)) 787 outfmt(out1, ","); 788 } 789 if (verbose && f) /* f should be normally be 0 */ 790 outfmt(out1, " +%#x", f); 791 outfmt(out1, "\n"); 792 } 793 794 static void 795 parseflags(char *s, int *p, int *n) 796 { 797 int *v, *w; 798 const struct flgnames *fn; 799 size_t len; 800 801 *p = 0; 802 *n = 0; 803 for (s = strtok(s, ","); s; s = strtok(NULL, ",")) { 804 switch (*s++) { 805 case '+': 806 v = p; 807 w = n; 808 break; 809 case '-': 810 v = n; 811 w = p; 812 break; 813 default: 814 error("Missing +/- indicator before flag %s", s-1); 815 } 816 817 len = strlen(s); 818 for (fn = nv; fn->name; fn++) 819 if (len >= fn->minch && strncmp(s,fn->name,len) == 0) { 820 *v |= fn->value; 821 *w &=~ fn->value; 822 break; 823 } 824 if (fn->name == 0) 825 error("Bad flag `%s'", s); 826 } 827 } 828 829 static void 830 setone(int fd, int pos, int neg, int verbose) 831 { 832 int f = getflags(fd, 1); 833 int n, cloexec; 834 835 if (f == -1) 836 return; 837 838 cloexec = -1; 839 if ((pos & O_CLOEXEC) && !(f & O_CLOEXEC)) 840 cloexec = FD_CLOEXEC; 841 if ((neg & O_CLOEXEC) && (f & O_CLOEXEC)) 842 cloexec = 0; 843 844 if (cloexec != -1 && fcntl(fd, F_SETFD, cloexec) == -1) 845 error("Can't set status for fd=%d (%s)", fd, strerror(errno)); 846 847 pos &= ~O_CLOEXEC; 848 neg &= ~O_CLOEXEC; 849 f &= ~O_CLOEXEC; 850 n = f; 851 n |= pos; 852 n &= ~neg; 853 if (n != f && fcntl(fd, F_SETFL, n) == -1) 854 error("Can't set flags for fd=%d (%s)", fd, strerror(errno)); 855 if (verbose) 856 printone(fd, 1, verbose, 1); 857 } 858 859 int 860 fdflagscmd(int argc, char *argv[]) 861 { 862 char *num; 863 int verbose = 0, ch, pos = 0, neg = 0; 864 char *setflags = NULL; 865 866 optreset = 1; optind = 1; /* initialize getopt */ 867 while ((ch = getopt(argc, argv, ":vs:")) != -1) 868 switch ((char)ch) { 869 case 'v': 870 verbose = 1; 871 break; 872 case 's': 873 if (setflags) 874 goto msg; 875 setflags = optarg; 876 break; 877 case '?': 878 default: 879 msg: 880 error("Usage: fdflags [-v] [-s <flags> fd] [fd...]"); 881 /* NOTREACHED */ 882 } 883 884 argc -= optind, argv += optind; 885 886 if (setflags) 887 parseflags(setflags, &pos, &neg); 888 889 if (argc == 0) { 890 int i; 891 892 if (setflags) 893 goto msg; 894 895 for (i = 0; i <= max_user_fd; i++) 896 printone(i, 0, verbose, 1); 897 return 0; 898 } 899 900 while ((num = *argv++) != NULL) { 901 int fd = number(num); 902 903 while (num[0] == '0' && num[1] != '\0') /* skip 0's */ 904 num++; 905 if (strlen(num) > 5) 906 error("%s too big to be a file descriptor", num); 907 908 if (setflags) 909 setone(fd, pos, neg, verbose); 910 else 911 printone(fd, 1, verbose, argc > 1); 912 } 913 return 0; 914 } 915 916 #undef MAX /* in case we inherited them from somewhere */ 917 #undef MIN 918 919 #define MIN(a,b) (/*CONSTCOND*/((a)<=(b)) ? (a) : (b)) 920 #define MAX(a,b) (/*CONSTCOND*/((a)>=(b)) ? (a) : (b)) 921 922 /* now make the compiler work for us... */ 923 #define MIN_REDIR MIN(MIN(MIN(MIN(NTO,NFROM), MIN(NTOFD,NFROMFD)), \ 924 MIN(MIN(NCLOBBER,NAPPEND), MIN(NHERE,NXHERE))), NFROMTO) 925 #define MAX_REDIR MAX(MAX(MAX(MAX(NTO,NFROM), MAX(NTOFD,NFROMFD)), \ 926 MAX(MAX(NCLOBBER,NAPPEND), MAX(NHERE,NXHERE))), NFROMTO) 927 928 static const char *redir_sym[MAX_REDIR - MIN_REDIR + 1] = { 929 [NTO - MIN_REDIR]= ">", 930 [NFROM - MIN_REDIR]= "<", 931 [NTOFD - MIN_REDIR]= ">&", 932 [NFROMFD - MIN_REDIR]= "<&", 933 [NCLOBBER - MIN_REDIR]= ">|", 934 [NAPPEND - MIN_REDIR]= ">>", 935 [NHERE - MIN_REDIR]= "<<", 936 [NXHERE - MIN_REDIR]= "<<", 937 [NFROMTO - MIN_REDIR]= "<>", 938 }; 939 940 int 941 outredir(struct output *out, union node *n, int sep) 942 { 943 if (n == NULL) 944 return 0; 945 if (n->type < MIN_REDIR || n->type > MAX_REDIR || 946 redir_sym[n->type - MIN_REDIR] == NULL) 947 return 0; 948 949 if (sep) 950 outc(sep, out); 951 952 /* 953 * ugly, but all redir node types have "fd" in same slot... 954 * (and code other places assumes it as well) 955 */ 956 if ((redir_sym[n->type - MIN_REDIR][0] == '<' && n->nfile.fd != 0) || 957 (redir_sym[n->type - MIN_REDIR][0] == '>' && n->nfile.fd != 1)) 958 outfmt(out, "%d", n->nfile.fd); 959 960 outstr(redir_sym[n->type - MIN_REDIR], out); 961 962 switch (n->type) { 963 case NHERE: 964 outstr("'...'", out); 965 break; 966 case NXHERE: 967 outstr("...", out); 968 break; 969 case NTOFD: 970 case NFROMFD: 971 if (n->ndup.dupfd < 0) 972 outc('-', out); 973 else 974 outfmt(out, "%d", n->ndup.dupfd); 975 break; 976 default: 977 outstr(n->nfile.expfname, out); 978 break; 979 } 980 return 1; 981 } 982
Indexes created Thu Oct 23 22:10:10 GMT 2025