1 /* $NetBSD: miscbltin.c,v 1.57 2025/07/03 03:54:40 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[] = "@(#)miscbltin.c 8.4 (Berkeley) 5/4/95"; 39 #else 40 __RCSID("$NetBSD: miscbltin.c,v 1.57 2025/07/03 03:54:40 kre Exp $"); 41 #endif 42 #endif /* not lint */ 43 44 /* 45 * Miscellaneous builtins. 46 */ 47 48 #include <sys/param.h> /* BSD4_4 */ 49 #include <sys/resource.h> 50 #include <sys/stat.h> 51 #include <sys/time.h> 52 #include <sys/types.h> /* quad_t */ 53 54 #include <ctype.h> 55 #include <errno.h> 56 #include <limits.h> 57 #include <stdlib.h> 58 #ifndef SMALL 59 #include <termios.h> 60 #endif 61 #include <unistd.h> 62 63 #include "shell.h" 64 #include "syntax.h" 65 #include "options.h" 66 #include "var.h" 67 #include "input.h" /* for whichprompt */ 68 #include "output.h" 69 #include "parser.h" /* for getprompt() */ 70 #include "memalloc.h" 71 #include "error.h" 72 #include "builtins.h" 73 #include "mystring.h" 74 #include "redir.h" /* for user_fd_limit */ 75 76 /* 77 * The read builtin. 78 * Backslashes escape the next char unless -r is specified. 79 * 80 * This uses unbuffered input, which may be avoidable in some cases. 81 * 82 * Note that if IFS=' :' then read x y should work so that: 83 * 'a b' x='a', y='b' 84 * ' a b ' x='a', y='b' 85 * ':b' x='', y='b' 86 * ':' x='', y='' 87 * '::' x='', y='' 88 * ': :' x='', y='' 89 * ':::' x='', y='::' 90 * ':b c:' x='', y='b c:' 91 */ 92 93 #ifndef SMALL 94 static int b_flag; 95 96 static int 97 setrawmode(int fd, int on, int end, struct termios *t) 98 { 99 struct termios n; 100 101 if (on) { 102 if (tcgetattr(fd, t) != 0) 103 return 0; 104 n = *t; 105 if (on == 1 && b_flag) { 106 n.c_cc[VEOL] = end; 107 } else { 108 cfmakeraw(&n); 109 n.c_iflag |= ICRNL; 110 n.c_oflag = t->c_oflag; 111 n.c_lflag |= ECHO | ISIG; 112 } 113 if (tcsetattr(fd, TCSADRAIN | TCSASOFT, &n) == 0) 114 return 1; 115 } else 116 (void)tcsetattr(fd, TCSADRAIN | TCSASOFT, t); 117 return 0; 118 } 119 120 static int 121 is_a_pipe(int fd) 122 { 123 if (lseek(fd, 0, SEEK_CUR) == -1 && errno == ESPIPE) { 124 errno = 0; 125 return 1; 126 } 127 return 0; 128 } 129 130 #define READ_BUFFER_SIZE 512 131 132 static int 133 next_read_char(int fd, size_t max) 134 { 135 static char buffer[READ_BUFFER_SIZE]; 136 static int pos = 0, len = 0; 137 138 if (max == 0) { 139 pos = len = 0; 140 return -1; 141 } 142 if (max == (size_t)-1) { 143 /* 144 * If possible, and necessary, rewind the file 145 * so unprocessed data can be read again next time 146 * 147 * If that fails, never mind (-b allows that to happen) 148 */ 149 if (b_flag && pos < len) 150 (void)lseek(fd, (off_t)(pos - len), SEEK_CUR); 151 return -1; 152 } 153 154 if (b_flag == 0) { 155 char c; 156 157 (void) max; 158 if (read(fd, &c, 1) != 1) 159 return -1; 160 return (c & 0xFF); 161 } 162 163 if (pos >= len) { 164 pos = 0; 165 if (max > sizeof buffer) 166 max = sizeof buffer; 167 len = read(fd, buffer, max); 168 if (len <= 0) 169 return -1; 170 } 171 172 return buffer[pos++] & 0xFF; 173 } 174 175 #define READ_OPTS "bd:n:p:r" 176 177 #else 178 179 static inline int 180 next_read_char(int fd, size_t max) 181 { 182 char c; 183 184 if (max == 0 || max == (size_t)-1) 185 return 0; 186 187 if (read(fd, &c, 1) != 1) 188 return -1; 189 return (c & 0xFF); 190 } 191 192 #define n_flag 0 193 #define maxlen 0 194 195 #define READ_OPTS "d:p:r" 196 197 #endif 198 199 int 200 readcmd(int argc, char **argv) 201 { 202 char **ap; 203 int c; 204 char end; 205 int r_flag; 206 char *prompt; 207 const char *ifs; 208 char *p; 209 int startword; 210 int status; 211 int i; 212 int is_ifs; 213 int saveall = 0; 214 int read_tty = 0; 215 ptrdiff_t wordlen = 0; 216 char *newifs = NULL; 217 struct stackmark mk; 218 219 #ifndef SMALL 220 struct termios ttystate; 221 int n_flag, maxlen; 222 int setraw = 0; 223 224 b_flag = 0; 225 n_flag = 0; 226 maxlen = READ_BUFFER_SIZE - 1; 227 #endif 228 229 end = '\n'; /* record delimiter */ 230 r_flag = 0; 231 prompt = NULL; 232 whichprompt = 2; /* for continuation lines */ 233 234 while ((i = nextopt(READ_OPTS)) != '\0') { 235 switch (i) { 236 case 'd': 237 end = *optionarg; /* even if '\0' */ 238 break; 239 case 'p': 240 prompt = optionarg; 241 break; 242 case 'r': 243 r_flag = 1; 244 break; 245 #ifndef SMALL 246 case 'n': 247 maxlen = number(optionarg); 248 if (maxlen > (INT_MAX >> 8) + 1) /* sanity */ 249 error("-n %s too large", optionarg); 250 n_flag = 1; 251 break; 252 case 'b': 253 if (!is_a_pipe(0)) 254 b_flag = 1; 255 break; 256 #endif 257 } 258 } 259 260 if (*(ap = argptr) == NULL) 261 error("variable name required\n" 262 #ifdef SMALL 263 "Usage: read [-r] [-d C] [-p prompt] var..."); 264 #else 265 "Usage: read [-br] [-d C] [-n len] [-p prompt] var..."); 266 267 while (*ap != NULL) { 268 if (!validname(*ap, '\0', NULL)) 269 error("'%s': invalid variable name", *ap); 270 ap++; 271 } 272 ap = argptr; 273 274 (void)next_read_char(0, 0); /* make sure the buffer is empty */ 275 #endif 276 277 if (isatty(0)) { 278 read_tty = 1; 279 if (prompt) { 280 out2str(prompt); 281 flushall(); 282 } 283 #ifndef SMALL 284 b_flag = 1; /* always buffer reads from ttys */ 285 286 if (n_flag || end != '\n') 287 setraw = setrawmode(0, 1 + n_flag, end, &ttystate); 288 #endif 289 } 290 291 if ((ifs = bltinlookup("IFS", 1)) == NULL) 292 ifs = " \t\n"; 293 294 setstackmark(&mk); 295 status = 0; 296 startword = 2; 297 STARTSTACKSTR(p); 298 299 #ifdef SMALL 300 for ( ; ; ) { 301 #else 302 for ( ; !n_flag || --maxlen >= 0 ; ) { 303 #endif 304 if ((c = next_read_char(0, maxlen + 1)) < 0) { 305 status = 1; 306 break; 307 } 308 if (c == '\\' && c != end && !r_flag) { 309 #ifndef SMALL 310 if (n_flag && --maxlen < 0) 311 break; 312 #endif 313 if ((c = next_read_char(0, maxlen + 1)) < 0) { 314 status = 1; 315 break; 316 } 317 if (c != '\n') /* \ \n is always just removed */ 318 goto wdch; 319 if (read_tty) 320 out2str(getprompt(NULL)); 321 continue; 322 } 323 if (c == end) 324 break; 325 if (c == '\0') 326 continue; 327 if (strchr(ifs, c)) 328 is_ifs = strchr(" \t\n", c) ? 1 : 2; 329 else 330 is_ifs = 0; 331 332 if (startword != 0) { 333 if (is_ifs == 1) { 334 /* Ignore leading IFS whitespace */ 335 if (saveall) 336 STPUTC(c, p); 337 continue; 338 } 339 if (is_ifs == 2 && startword == 1) { 340 /* Only one non-whitespace IFS per word */ 341 startword = 2; 342 if (saveall) 343 STPUTC(c, p); 344 continue; 345 } 346 } 347 348 if (is_ifs == 0) { 349 wdch:; 350 if (c == '\0') /* always ignore attempts to input \0 */ 351 continue; 352 /* append this character to the current variable */ 353 startword = 0; 354 if (saveall) 355 /* Not just a spare terminator */ 356 saveall++; 357 STPUTC(c, p); 358 wordlen = p - stackblock(); 359 continue; 360 } 361 362 /* end of variable... */ 363 startword = is_ifs; 364 365 if (ap[1] == NULL) { 366 /* Last variable needs all IFS chars */ 367 saveall++; 368 STPUTC(c, p); 369 continue; 370 } 371 372 if (equal(*ap, "IFS")) { 373 /* 374 * we must not alter the value of IFS, as our 375 * local "ifs" var is (perhaps) pointing at it, 376 * at best we would be using data after free() 377 * the next time we reference ifs - but that mem 378 * may have been reused for something different. 379 * 380 * note that this might occur several times 381 */ 382 STPUTC('\0', p); 383 newifs = grabstackstr(p); 384 } else { 385 STACKSTRNUL(p); 386 setvar(*ap, stackblock(), 0); 387 } 388 ap++; 389 STARTSTACKSTR(p); 390 wordlen = 0; 391 } 392 STACKSTRNUL(p); 393 394 #ifndef SMALL 395 (void)next_read_char(0, (size_t)-1); /* attempt to seek back */ 396 if (setraw) 397 setrawmode(0, 0, end, &ttystate); 398 #endif 399 400 401 /* Remove trailing IFS chars */ 402 for (; stackblock() + wordlen <= --p; *p = 0) { 403 if (!strchr(ifs, *p)) 404 break; 405 if (strchr(" \t\n", *p)) 406 /* Always remove whitespace */ 407 continue; 408 if (saveall > 1) 409 /* Don't remove non-whitespace unless it was naked */ 410 break; 411 } 412 413 /* 414 * If IFS was one of the variables named, we can finally set it now 415 * (no further references to ifs will be made) 416 */ 417 if (newifs != NULL) 418 setvar("IFS", newifs, 0); 419 420 /* 421 * Now we can assign to the final variable (which might 422 * also be IFS, hence the ordering here) 423 */ 424 setvar(*ap, stackblock(), 0); 425 426 /* Set any remaining args to "" */ 427 while (*++ap != NULL) 428 setvar(*ap, nullstr, 0); 429 430 popstackmark(&mk); 431 return status; 432 } 433 434 435 436 int 437 umaskcmd(int argc, char **argv) 438 { 439 char *ap; 440 mode_t mask; 441 int i; 442 int symbolic_mode = 0; 443 444 while ((i = nextopt("S")) != '\0') { 445 symbolic_mode = 1; 446 } 447 448 INTOFF; 449 mask = umask(0); 450 umask(mask); 451 INTON; 452 453 if ((ap = *argptr) == NULL) { 454 if (symbolic_mode) { 455 char u[4], g[4], o[4]; 456 457 i = 0; 458 if ((mask & S_IRUSR) == 0) 459 u[i++] = 'r'; 460 if ((mask & S_IWUSR) == 0) 461 u[i++] = 'w'; 462 if ((mask & S_IXUSR) == 0) 463 u[i++] = 'x'; 464 u[i] = '\0'; 465 466 i = 0; 467 if ((mask & S_IRGRP) == 0) 468 g[i++] = 'r'; 469 if ((mask & S_IWGRP) == 0) 470 g[i++] = 'w'; 471 if ((mask & S_IXGRP) == 0) 472 g[i++] = 'x'; 473 g[i] = '\0'; 474 475 i = 0; 476 if ((mask & S_IROTH) == 0) 477 o[i++] = 'r'; 478 if ((mask & S_IWOTH) == 0) 479 o[i++] = 'w'; 480 if ((mask & S_IXOTH) == 0) 481 o[i++] = 'x'; 482 o[i] = '\0'; 483 484 out1fmt("u=%s,g=%s,o=%s\n", u, g, o); 485 } else { 486 out1fmt("%.4o\n", mask); 487 } 488 } else { 489 if (is_digit(*ap)) { 490 int range = 0; 491 492 mask = 0; 493 do { 494 if (*ap >= '8' || *ap < '0') 495 error("Not a valid octal number: '%s'", 496 *argptr); 497 mask = (mask << 3) + (*ap - '0'); 498 if (mask & ~07777) 499 range = 1; 500 } while (*++ap != '\0'); 501 if (range) 502 error("Mask constant '%s' out of range", *argptr); 503 umask(mask); 504 } else { 505 void *set; 506 507 INTOFF; 508 if ((set = setmode(ap)) != 0) { 509 mask = getmode(set, ~mask & 0777); 510 ckfree(set); 511 } 512 INTON; 513 if (!set) 514 error("Cannot set mode `%s' (%s)", ap, 515 strerror(errno)); 516 517 umask(~mask & 0777); 518 } 519 } 520 flushout(out1); 521 if (io_err(out1)) { 522 out2str("umask: I/O error\n"); 523 return 1; 524 } 525 return 0; 526 } 527 528 /* 529 * ulimit builtin 530 * 531 * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and 532 * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with 533 * ash by J.T. Conklin. 534 * 535 * Public domain. 536 */ 537 538 struct limits { 539 const char *name; 540 const char *unit; 541 char option; 542 int8_t cmd; /* all RLIMIT_xxx are <= 127 */ 543 unsigned short factor; /* multiply by to get rlim_{cur,max} values */ 544 }; 545 546 #define OPTSTRING_BASE "HSa" 547 548 static const struct limits limits[] = { 549 #ifdef RLIMIT_CPU 550 { "time", "seconds", 't', RLIMIT_CPU, 1 }, 551 #define OPTSTRING_t OPTSTRING_BASE "t" 552 #else 553 #define OPTSTRING_t OPTSTRING_BASE 554 #endif 555 #ifdef RLIMIT_FSIZE 556 { "file", "blocks", 'f', RLIMIT_FSIZE, 512 }, 557 #define OPTSTRING_f OPTSTRING_t "f" 558 #else 559 #define OPTSTRING_f OPTSTRING_t 560 #endif 561 #ifdef RLIMIT_DATA 562 { "data", "kbytes", 'd', RLIMIT_DATA, 1024 }, 563 #define OPTSTRING_d OPTSTRING_f "d" 564 #else 565 #define OPTSTRING_d OPTSTRING_f 566 #endif 567 #ifdef RLIMIT_STACK 568 { "stack", "kbytes", 's', RLIMIT_STACK, 1024 }, 569 #define OPTSTRING_s OPTSTRING_d "s" 570 #else 571 #define OPTSTRING_s OPTSTRING_d 572 #endif 573 #ifdef RLIMIT_CORE 574 { "coredump", "blocks", 'c', RLIMIT_CORE, 512 }, 575 #define OPTSTRING_c OPTSTRING_s "c" 576 #else 577 #define OPTSTRING_c OPTSTRING_s 578 #endif 579 #ifdef RLIMIT_RSS 580 { "memory", "kbytes", 'm', RLIMIT_RSS, 1024 }, 581 #define OPTSTRING_m OPTSTRING_c "m" 582 #else 583 #define OPTSTRING_m OPTSTRING_c 584 #endif 585 #ifdef RLIMIT_MEMLOCK 586 { "locked memory","kbytes", 'l', RLIMIT_MEMLOCK, 1024 }, 587 #define OPTSTRING_l OPTSTRING_m "l" 588 #else 589 #define OPTSTRING_l OPTSTRING_m 590 #endif 591 #ifdef RLIMIT_NTHR 592 { "thread", "threads", 'r', RLIMIT_NTHR, 1 }, 593 #define OPTSTRING_r OPTSTRING_l "r" 594 #else 595 #define OPTSTRING_r OPTSTRING_l 596 #endif 597 #ifdef RLIMIT_NPROC 598 { "process", "processes", 'p', RLIMIT_NPROC, 1 }, 599 #define OPTSTRING_p OPTSTRING_r "p" 600 #else 601 #define OPTSTRING_p OPTSTRING_r 602 #endif 603 #ifdef RLIMIT_NOFILE 604 { "nofiles", "descriptors", 'n', RLIMIT_NOFILE, 1 }, 605 #define OPTSTRING_n OPTSTRING_p "n" 606 #else 607 #define OPTSTRING_n OPTSTRING_p 608 #endif 609 #ifdef RLIMIT_VMEM 610 { "vmemory", "kbytes", 'v', RLIMIT_VMEM, 1024 }, 611 #define OPTSTRING_v OPTSTRING_n "v" 612 #else 613 #define OPTSTRING_v OPTSTRING_n 614 #endif 615 #ifdef RLIMIT_SWAP 616 { "swap", "kbytes", 'w', RLIMIT_SWAP, 1024 }, 617 #define OPTSTRING_w OPTSTRING_v "w" 618 #else 619 #define OPTSTRING_w OPTSTRING_v 620 #endif 621 #ifdef RLIMIT_SBSIZE 622 { "sbsize", "bytes", 'b', RLIMIT_SBSIZE, 1 }, 623 #define OPTSTRING_b OPTSTRING_w "b" 624 #else 625 #define OPTSTRING_b OPTSTRING_w 626 #endif 627 { NULL, NULL, '\0', 0, 0 } 628 }; 629 #define OPTSTRING OPTSTRING_b 630 631 int 632 ulimitcmd(int argc, char **argv) 633 { 634 int c; 635 rlim_t val = 0; 636 enum { SOFT = 0x1, HARD = 0x2 } 637 how = 0, which; 638 const struct limits *l; 639 int set, all = 0; 640 int optc, what; 641 struct rlimit limit; 642 643 what = 'f'; 644 while ((optc = nextopt(OPTSTRING)) != '\0') 645 switch (optc) { 646 case 'H': 647 how |= HARD; 648 break; 649 case 'S': 650 how |= SOFT; 651 break; 652 case 'a': 653 all = 1; 654 break; 655 default: 656 what = optc; 657 } 658 659 for (l = limits; l->name && l->option != what; l++) 660 ; 661 if (!l->name) 662 error("internal error (%c)", what); 663 664 set = *argptr ? 1 : 0; 665 if (set) { 666 char *p = *argptr; 667 668 if (all || argptr[1]) 669 error("too many arguments"); 670 if (how == 0) 671 how = HARD | SOFT; 672 673 if (strcmp(p, "unlimited") == 0) 674 val = RLIM_INFINITY; 675 else { 676 val = (rlim_t) 0; 677 678 while ((c = *p++) >= '0' && c <= '9') { 679 if (val >= RLIM_INFINITY/10) 680 error("%s: value overflow", *argptr); 681 val = (val * 10); 682 if (val >= RLIM_INFINITY - (long)(c - '0')) 683 error("%s: value overflow", *argptr); 684 val += (long)(c - '0'); 685 } 686 if (c) 687 error("%s: bad number", *argptr); 688 if (val > RLIM_INFINITY / l->factor) 689 error("%s: value overflow", *argptr); 690 val *= l->factor; 691 } 692 } else if (how == 0) 693 how = SOFT; 694 695 if (all) { 696 for (l = limits; l->name; l++) { 697 getrlimit(l->cmd, &limit); 698 out1fmt("%-13s (-%c %-11s) ", l->name, l->option, 699 l->unit); 700 701 which = how; 702 while (which != 0) { 703 if (which & SOFT) { 704 val = limit.rlim_cur; 705 which &= ~SOFT; 706 } else if (which & HARD) { 707 val = limit.rlim_max; 708 which &= ~HARD; 709 } 710 711 if (val == RLIM_INFINITY) 712 out1fmt("unlimited"); 713 else { 714 val /= l->factor; 715 #ifdef BSD4_4 716 out1fmt("%9lld", (long long) val); 717 #else 718 out1fmt("%9ld", (long) val); 719 #endif 720 } 721 out1fmt("%c", which ? '\t' : '\n'); 722 } 723 } 724 goto done; 725 } 726 727 if (getrlimit(l->cmd, &limit) == -1) 728 error("error getting limit (%s)", strerror(errno)); 729 if (set) { 730 if (how & HARD) 731 limit.rlim_max = val; 732 if (how & SOFT) 733 limit.rlim_cur = val; 734 if (setrlimit(l->cmd, &limit) < 0) 735 error("error setting limit (%s)", strerror(errno)); 736 if (l->cmd == RLIMIT_NOFILE) 737 user_fd_limit = sysconf(_SC_OPEN_MAX); 738 } else { 739 if (how & SOFT) 740 val = limit.rlim_cur; 741 else if (how & HARD) 742 val = limit.rlim_max; 743 744 if (val == RLIM_INFINITY) 745 out1fmt("unlimited\n"); 746 else 747 { 748 val /= l->factor; 749 #ifdef BSD4_4 750 out1fmt("%lld\n", (long long) val); 751 #else 752 out1fmt("%ld\n", (long) val); 753 #endif 754 } 755 } 756 done:; 757 flushout(out1); 758 if (io_err(out1)) { 759 out2str("ulimit: I/O error (stdout)\n"); 760 return 1; 761 } 762 return 0; 763 } 764