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