1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 #ifndef lint 36 #if 0 37 static char sccsid[] = "@(#)miscbltin.c 8.4 (Berkeley) 5/4/95"; 38 #endif 39 #endif /* not lint */ 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 /* 44 * Miscellaneous builtins. 45 */ 46 47 #include <sys/types.h> 48 #include <sys/stat.h> 49 #include <sys/time.h> 50 #include <sys/resource.h> 51 #include <unistd.h> 52 #include <errno.h> 53 #include <stdint.h> 54 #include <stdio.h> 55 #include <stdlib.h> 56 57 #include "shell.h" 58 #include "options.h" 59 #include "var.h" 60 #include "output.h" 61 #include "memalloc.h" 62 #include "error.h" 63 #include "mystring.h" 64 #include "syntax.h" 65 #include "trap.h" 66 67 #undef eflag 68 69 #define READ_BUFLEN 1024 70 struct fdctx { 71 int fd; 72 size_t off; /* offset in buf */ 73 size_t buflen; 74 char *ep; /* tail pointer */ 75 char buf[READ_BUFLEN]; 76 }; 77 78 static void fdctx_init(int, struct fdctx *); 79 static void fdctx_destroy(struct fdctx *); 80 static ssize_t fdgetc(struct fdctx *, char *); 81 int readcmd(int, char **); 82 int umaskcmd(int, char **); 83 int ulimitcmd(int, char **); 84 85 static void 86 fdctx_init(int fd, struct fdctx *fdc) 87 { 88 off_t cur; 89 90 /* Check if fd is seekable. */ 91 cur = lseek(fd, 0, SEEK_CUR); 92 *fdc = (struct fdctx){ 93 .fd = fd, 94 .buflen = (cur != -1) ? READ_BUFLEN : 1, 95 .ep = &fdc->buf[0], /* No data */ 96 }; 97 } 98 99 static ssize_t 100 fdgetc(struct fdctx *fdc, char *c) 101 { 102 ssize_t nread; 103 104 if (&fdc->buf[fdc->off] == fdc->ep) { 105 nread = read(fdc->fd, fdc->buf, fdc->buflen); 106 if (nread > 0) { 107 fdc->off = 0; 108 fdc->ep = fdc->buf + nread; 109 } else 110 return (nread); 111 } 112 *c = fdc->buf[fdc->off++]; 113 114 return (1); 115 } 116 117 static void 118 fdctx_destroy(struct fdctx *fdc) 119 { 120 off_t residue; 121 122 if (fdc->buflen > 1) { 123 /* 124 * Reposition the file offset. Here is the layout of buf: 125 * 126 * | off 127 * v 128 * |*****************|-------| 129 * buf ep buf+buflen 130 * |<- residue ->| 131 * 132 * off: current character 133 * ep: offset just after read(2) 134 * residue: length for reposition 135 */ 136 residue = (fdc->ep - fdc->buf) - fdc->off; 137 if (residue > 0) 138 (void) lseek(fdc->fd, -residue, SEEK_CUR); 139 } 140 } 141 142 /* 143 * The read builtin. The -r option causes backslashes to be treated like 144 * ordinary characters. 145 * 146 * This uses unbuffered input, which may be avoidable in some cases. 147 * 148 * Note that if IFS=' :' then read x y should work so that: 149 * 'a b' x='a', y='b' 150 * ' a b ' x='a', y='b' 151 * ':b' x='', y='b' 152 * ':' x='', y='' 153 * '::' x='', y='' 154 * ': :' x='', y='' 155 * ':::' x='', y='::' 156 * ':b c:' x='', y='b c:' 157 */ 158 159 int 160 readcmd(int argc __unused, char **argv __unused) 161 { 162 char **ap; 163 int backslash; 164 char c; 165 int rflag; 166 char *prompt; 167 const char *ifs; 168 char *p; 169 int startword; 170 int status; 171 int i; 172 int is_ifs; 173 int saveall = 0; 174 ptrdiff_t lastnonifs, lastnonifsws; 175 struct timeval tv; 176 char *tvptr; 177 fd_set ifds; 178 ssize_t nread; 179 int sig; 180 struct fdctx fdctx; 181 182 rflag = 0; 183 prompt = NULL; 184 tv.tv_sec = -1; 185 tv.tv_usec = 0; 186 while ((i = nextopt("erp:t:")) != '\0') { 187 switch(i) { 188 case 'p': 189 prompt = shoptarg; 190 break; 191 case 'e': 192 break; 193 case 'r': 194 rflag = 1; 195 break; 196 case 't': 197 tv.tv_sec = strtol(shoptarg, &tvptr, 0); 198 if (tvptr == shoptarg) 199 error("timeout value"); 200 switch(*tvptr) { 201 case 0: 202 case 's': 203 break; 204 case 'h': 205 tv.tv_sec *= 60; 206 /* FALLTHROUGH */ 207 case 'm': 208 tv.tv_sec *= 60; 209 break; 210 default: 211 error("timeout unit"); 212 } 213 break; 214 } 215 } 216 if (prompt && isatty(0)) { 217 out2str(prompt); 218 flushall(); 219 } 220 if (*(ap = argptr) == NULL) 221 error("arg count"); 222 if ((ifs = bltinlookup("IFS", 1)) == NULL) 223 ifs = " \t\n"; 224 225 if (tv.tv_sec >= 0) { 226 /* 227 * Wait for something to become available. 228 */ 229 FD_ZERO(&ifds); 230 FD_SET(0, &ifds); 231 status = select(1, &ifds, NULL, NULL, &tv); 232 /* 233 * If there's nothing ready, return an error. 234 */ 235 if (status <= 0) { 236 sig = pendingsig; 237 return (128 + (sig != 0 ? sig : SIGALRM)); 238 } 239 } 240 241 status = 0; 242 startword = 2; 243 backslash = 0; 244 STARTSTACKSTR(p); 245 lastnonifs = lastnonifsws = -1; 246 fdctx_init(STDIN_FILENO, &fdctx); 247 for (;;) { 248 nread = fdgetc(&fdctx, &c); 249 if (nread == -1) { 250 if (errno == EINTR) { 251 sig = pendingsig; 252 if (sig == 0) 253 continue; 254 status = 128 + sig; 255 break; 256 } 257 warning("read error: %s", strerror(errno)); 258 status = 2; 259 break; 260 } else if (nread != 1) { 261 status = 1; 262 break; 263 } 264 if (c == '\0') 265 continue; 266 CHECKSTRSPACE(1, p); 267 if (backslash) { 268 backslash = 0; 269 if (c != '\n') { 270 startword = 0; 271 lastnonifs = lastnonifsws = p - stackblock(); 272 USTPUTC(c, p); 273 } 274 continue; 275 } 276 if (!rflag && c == '\\') { 277 backslash++; 278 continue; 279 } 280 if (c == '\n') 281 break; 282 if (strchr(ifs, c)) 283 is_ifs = strchr(" \t\n", c) ? 1 : 2; 284 else 285 is_ifs = 0; 286 287 if (startword != 0) { 288 if (is_ifs == 1) { 289 /* Ignore leading IFS whitespace */ 290 if (saveall) 291 USTPUTC(c, p); 292 continue; 293 } 294 if (is_ifs == 2 && startword == 1) { 295 /* Only one non-whitespace IFS per word */ 296 startword = 2; 297 if (saveall) { 298 lastnonifsws = p - stackblock(); 299 USTPUTC(c, p); 300 } 301 continue; 302 } 303 } 304 305 if (is_ifs == 0) { 306 /* append this character to the current variable */ 307 startword = 0; 308 if (saveall) 309 /* Not just a spare terminator */ 310 saveall++; 311 lastnonifs = lastnonifsws = p - stackblock(); 312 USTPUTC(c, p); 313 continue; 314 } 315 316 /* end of variable... */ 317 startword = is_ifs; 318 319 if (ap[1] == NULL) { 320 /* Last variable needs all IFS chars */ 321 saveall++; 322 if (is_ifs == 2) 323 lastnonifsws = p - stackblock(); 324 USTPUTC(c, p); 325 continue; 326 } 327 328 STACKSTRNUL(p); 329 setvar(*ap, stackblock(), 0); 330 ap++; 331 STARTSTACKSTR(p); 332 lastnonifs = lastnonifsws = -1; 333 } 334 fdctx_destroy(&fdctx); 335 STACKSTRNUL(p); 336 337 /* 338 * Remove trailing IFS chars: always remove whitespace, don't remove 339 * non-whitespace unless it was naked 340 */ 341 if (saveall <= 1) 342 lastnonifsws = lastnonifs; 343 stackblock()[lastnonifsws + 1] = '\0'; 344 setvar(*ap, stackblock(), 0); 345 346 /* Set any remaining args to "" */ 347 while (*++ap != NULL) 348 setvar(*ap, "", 0); 349 return status; 350 } 351 352 353 354 int 355 umaskcmd(int argc __unused, char **argv __unused) 356 { 357 char *ap; 358 int mask; 359 int i; 360 int symbolic_mode = 0; 361 362 while ((i = nextopt("S")) != '\0') { 363 symbolic_mode = 1; 364 } 365 366 INTOFF; 367 mask = umask(0); 368 umask(mask); 369 INTON; 370 371 if ((ap = *argptr) == NULL) { 372 if (symbolic_mode) { 373 char u[4], g[4], o[4]; 374 375 i = 0; 376 if ((mask & S_IRUSR) == 0) 377 u[i++] = 'r'; 378 if ((mask & S_IWUSR) == 0) 379 u[i++] = 'w'; 380 if ((mask & S_IXUSR) == 0) 381 u[i++] = 'x'; 382 u[i] = '\0'; 383 384 i = 0; 385 if ((mask & S_IRGRP) == 0) 386 g[i++] = 'r'; 387 if ((mask & S_IWGRP) == 0) 388 g[i++] = 'w'; 389 if ((mask & S_IXGRP) == 0) 390 g[i++] = 'x'; 391 g[i] = '\0'; 392 393 i = 0; 394 if ((mask & S_IROTH) == 0) 395 o[i++] = 'r'; 396 if ((mask & S_IWOTH) == 0) 397 o[i++] = 'w'; 398 if ((mask & S_IXOTH) == 0) 399 o[i++] = 'x'; 400 o[i] = '\0'; 401 402 out1fmt("u=%s,g=%s,o=%s\n", u, g, o); 403 } else { 404 out1fmt("%.4o\n", mask); 405 } 406 } else { 407 if (is_digit(*ap)) { 408 mask = 0; 409 do { 410 if (*ap >= '8' || *ap < '0') 411 error("Illegal number: %s", *argptr); 412 mask = (mask << 3) + (*ap - '0'); 413 } while (*++ap != '\0'); 414 umask(mask); 415 } else { 416 void *set; 417 INTOFF; 418 if ((set = setmode (ap)) == NULL) 419 error("Illegal number: %s", ap); 420 421 mask = getmode (set, ~mask & 0777); 422 umask(~mask & 0777); 423 free(set); 424 INTON; 425 } 426 } 427 return 0; 428 } 429 430 /* 431 * ulimit builtin 432 * 433 * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and 434 * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with 435 * ash by J.T. Conklin. 436 * 437 * Public domain. 438 */ 439 440 struct limits { 441 const char *name; 442 const char *units; 443 int cmd; 444 short factor; /* multiply by to get rlim_{cur,max} values */ 445 char option; 446 }; 447 448 static const struct limits limits[] = { 449 #ifdef RLIMIT_CPU 450 { "cpu time", "seconds", RLIMIT_CPU, 1, 't' }, 451 #endif 452 #ifdef RLIMIT_FSIZE 453 { "file size", "512-blocks", RLIMIT_FSIZE, 512, 'f' }, 454 #endif 455 #ifdef RLIMIT_DATA 456 { "data seg size", "kbytes", RLIMIT_DATA, 1024, 'd' }, 457 #endif 458 #ifdef RLIMIT_STACK 459 { "stack size", "kbytes", RLIMIT_STACK, 1024, 's' }, 460 #endif 461 #ifdef RLIMIT_CORE 462 { "core file size", "512-blocks", RLIMIT_CORE, 512, 'c' }, 463 #endif 464 #ifdef RLIMIT_RSS 465 { "max memory size", "kbytes", RLIMIT_RSS, 1024, 'm' }, 466 #endif 467 #ifdef RLIMIT_MEMLOCK 468 { "locked memory", "kbytes", RLIMIT_MEMLOCK, 1024, 'l' }, 469 #endif 470 #ifdef RLIMIT_NPROC 471 { "max user processes", (char *)0, RLIMIT_NPROC, 1, 'u' }, 472 #endif 473 #ifdef RLIMIT_NOFILE 474 { "open files", (char *)0, RLIMIT_NOFILE, 1, 'n' }, 475 #endif 476 #ifdef RLIMIT_VMEM 477 { "virtual mem size", "kbytes", RLIMIT_VMEM, 1024, 'v' }, 478 #endif 479 #ifdef RLIMIT_SWAP 480 { "swap limit", "kbytes", RLIMIT_SWAP, 1024, 'w' }, 481 #endif 482 #ifdef RLIMIT_SBSIZE 483 { "socket buffer size", "bytes", RLIMIT_SBSIZE, 1, 'b' }, 484 #endif 485 #ifdef RLIMIT_NPTS 486 { "pseudo-terminals", (char *)0, RLIMIT_NPTS, 1, 'p' }, 487 #endif 488 #ifdef RLIMIT_KQUEUES 489 { "kqueues", (char *)0, RLIMIT_KQUEUES, 1, 'k' }, 490 #endif 491 #ifdef RLIMIT_UMTXP 492 { "umtx shared locks", (char *)0, RLIMIT_UMTXP, 1, 'o' }, 493 #endif 494 { (char *) 0, (char *)0, 0, 0, '\0' } 495 }; 496 497 enum limithow { SOFT = 0x1, HARD = 0x2 }; 498 499 static void 500 printlimit(enum limithow how, const struct rlimit *limit, 501 const struct limits *l) 502 { 503 rlim_t val = 0; 504 505 if (how & SOFT) 506 val = limit->rlim_cur; 507 else if (how & HARD) 508 val = limit->rlim_max; 509 if (val == RLIM_INFINITY) 510 out1str("unlimited\n"); 511 else 512 { 513 val /= l->factor; 514 out1fmt("%jd\n", (intmax_t)val); 515 } 516 } 517 518 int 519 ulimitcmd(int argc __unused, char **argv __unused) 520 { 521 rlim_t val = 0; 522 enum limithow how = SOFT | HARD; 523 const struct limits *l; 524 int set, all = 0; 525 int optc, what; 526 struct rlimit limit; 527 528 what = 'f'; 529 while ((optc = nextopt("HSatfdsmcnuvlbpwko")) != '\0') 530 switch (optc) { 531 case 'H': 532 how = HARD; 533 break; 534 case 'S': 535 how = SOFT; 536 break; 537 case 'a': 538 all = 1; 539 break; 540 default: 541 what = optc; 542 } 543 544 for (l = limits; l->name && l->option != what; l++) 545 ; 546 if (!l->name) 547 error("internal error (%c)", what); 548 549 set = *argptr ? 1 : 0; 550 if (set) { 551 char *p = *argptr; 552 553 if (all || argptr[1]) 554 error("too many arguments"); 555 if (strcmp(p, "unlimited") == 0) 556 val = RLIM_INFINITY; 557 else { 558 char *end; 559 uintmax_t uval; 560 561 if (*p < '0' || *p > '9') 562 error("bad number"); 563 errno = 0; 564 uval = strtoumax(p, &end, 10); 565 if (errno != 0 || *end != '\0') 566 error("bad number"); 567 if (uval > UINTMAX_MAX / l->factor) 568 error("bad number"); 569 uval *= l->factor; 570 val = (rlim_t)uval; 571 if (val < 0 || (uintmax_t)val != uval || 572 val == RLIM_INFINITY) 573 error("bad number"); 574 } 575 } 576 if (all) { 577 for (l = limits; l->name; l++) { 578 char optbuf[40]; 579 if (getrlimit(l->cmd, &limit) < 0) 580 error("can't get limit: %s", strerror(errno)); 581 582 if (l->units) 583 snprintf(optbuf, sizeof(optbuf), 584 "(%s, -%c) ", l->units, l->option); 585 else 586 snprintf(optbuf, sizeof(optbuf), 587 "(-%c) ", l->option); 588 out1fmt("%-18s %18s ", l->name, optbuf); 589 printlimit(how, &limit, l); 590 } 591 return 0; 592 } 593 594 if (getrlimit(l->cmd, &limit) < 0) 595 error("can't get limit: %s", strerror(errno)); 596 if (set) { 597 if (how & SOFT) 598 limit.rlim_cur = val; 599 if (how & HARD) 600 limit.rlim_max = val; 601 if (setrlimit(l->cmd, &limit) < 0) 602 error("bad limit: %s", strerror(errno)); 603 } else 604 printlimit(how, &limit, l); 605 return 0; 606 } 607