1 /*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)miscbltin.c 8.4 (Berkeley) 5/4/95";
36 #endif
37 #endif /* not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40
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
fdctx_init(int fd,struct fdctx * fdc)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
fdgetc(struct fdctx * fdc,char * c)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
fdctx_destroy(struct fdctx * fdc)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 * This uses unbuffered input, which may be avoidable in some cases.
145 *
146 * Note that if IFS=' :' then read x y should work so that:
147 * 'a b' x='a', y='b'
148 * ' a b ' x='a', y='b'
149 * ':b' x='', y='b'
150 * ':' x='', y=''
151 * '::' x='', y=''
152 * ': :' x='', y=''
153 * ':::' x='', y='::'
154 * ':b c:' x='', y='b c:'
155 */
156
157 int
readcmd(int argc __unused,char ** argv __unused)158 readcmd(int argc __unused, char **argv __unused)
159 {
160 char **ap;
161 int backslash;
162 char c;
163 int rflag;
164 char *prompt;
165 const char *ifs;
166 char *p;
167 int startword;
168 int status;
169 int i;
170 int is_ifs;
171 int saveall = 0;
172 ptrdiff_t lastnonifs, lastnonifsws;
173 struct timeval tv;
174 char *tvptr;
175 fd_set ifds;
176 ssize_t nread;
177 int sig;
178 struct fdctx fdctx;
179
180 rflag = 0;
181 prompt = NULL;
182 tv.tv_sec = -1;
183 tv.tv_usec = 0;
184 while ((i = nextopt("erp:t:")) != '\0') {
185 switch(i) {
186 case 'p':
187 prompt = shoptarg;
188 break;
189 case 'e':
190 break;
191 case 'r':
192 rflag = 1;
193 break;
194 case 't':
195 tv.tv_sec = strtol(shoptarg, &tvptr, 0);
196 if (tvptr == shoptarg)
197 error("timeout value");
198 switch(*tvptr) {
199 case 0:
200 case 's':
201 break;
202 case 'h':
203 tv.tv_sec *= 60;
204 /* FALLTHROUGH */
205 case 'm':
206 tv.tv_sec *= 60;
207 break;
208 default:
209 error("timeout unit");
210 }
211 break;
212 }
213 }
214 if (prompt && isatty(0)) {
215 out2str(prompt);
216 flushall();
217 }
218 if (*(ap = argptr) == NULL)
219 error("arg count");
220 if ((ifs = bltinlookup("IFS", 1)) == NULL)
221 ifs = " \t\n";
222
223 if (tv.tv_sec >= 0) {
224 /*
225 * Wait for something to become available.
226 */
227 FD_ZERO(&ifds);
228 FD_SET(0, &ifds);
229 status = select(1, &ifds, NULL, NULL, &tv);
230 /*
231 * If there's nothing ready, return an error.
232 */
233 if (status <= 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 nread = fdgetc(&fdctx, &c);
247 if (nread == -1) {
248 if (errno == EINTR) {
249 sig = pendingsig;
250 if (sig == 0)
251 continue;
252 status = 128 + sig;
253 break;
254 }
255 warning("read error: %s", strerror(errno));
256 status = 2;
257 break;
258 } else if (nread != 1) {
259 status = 1;
260 break;
261 }
262 if (c == '\0')
263 continue;
264 CHECKSTRSPACE(1, p);
265 if (backslash) {
266 backslash = 0;
267 if (c != '\n') {
268 startword = 0;
269 lastnonifs = lastnonifsws = p - stackblock();
270 USTPUTC(c, p);
271 }
272 continue;
273 }
274 if (!rflag && c == '\\') {
275 backslash++;
276 continue;
277 }
278 if (c == '\n')
279 break;
280 if (strchr(ifs, c))
281 is_ifs = strchr(" \t\n", c) ? 1 : 2;
282 else
283 is_ifs = 0;
284
285 if (startword != 0) {
286 if (is_ifs == 1) {
287 /* Ignore leading IFS whitespace */
288 if (saveall)
289 USTPUTC(c, p);
290 continue;
291 }
292 if (is_ifs == 2 && startword == 1) {
293 /* Only one non-whitespace IFS per word */
294 startword = 2;
295 if (saveall) {
296 lastnonifsws = p - stackblock();
297 USTPUTC(c, p);
298 }
299 continue;
300 }
301 }
302
303 if (is_ifs == 0) {
304 /* append this character to the current variable */
305 startword = 0;
306 if (saveall)
307 /* Not just a spare terminator */
308 saveall++;
309 lastnonifs = lastnonifsws = p - stackblock();
310 USTPUTC(c, p);
311 continue;
312 }
313
314 /* end of variable... */
315 startword = is_ifs;
316
317 if (ap[1] == NULL) {
318 /* Last variable needs all IFS chars */
319 saveall++;
320 if (is_ifs == 2)
321 lastnonifsws = p - stackblock();
322 USTPUTC(c, p);
323 continue;
324 }
325
326 STACKSTRNUL(p);
327 setvar(*ap, stackblock(), 0);
328 ap++;
329 STARTSTACKSTR(p);
330 lastnonifs = lastnonifsws = -1;
331 }
332 fdctx_destroy(&fdctx);
333 STACKSTRNUL(p);
334
335 /*
336 * Remove trailing IFS chars: always remove whitespace, don't remove
337 * non-whitespace unless it was naked
338 */
339 if (saveall <= 1)
340 lastnonifsws = lastnonifs;
341 stackblock()[lastnonifsws + 1] = '\0';
342 setvar(*ap, stackblock(), 0);
343
344 /* Set any remaining args to "" */
345 while (*++ap != NULL)
346 setvar(*ap, "", 0);
347 return status;
348 }
349
350
351
352 int
umaskcmd(int argc __unused,char ** argv __unused)353 umaskcmd(int argc __unused, char **argv __unused)
354 {
355 char *ap;
356 int mask;
357 int i;
358 int symbolic_mode = 0;
359
360 while ((i = nextopt("S")) != '\0') {
361 symbolic_mode = 1;
362 }
363
364 INTOFF;
365 mask = umask(0);
366 umask(mask);
367 INTON;
368
369 if ((ap = *argptr) == NULL) {
370 if (symbolic_mode) {
371 char u[4], g[4], o[4];
372
373 i = 0;
374 if ((mask & S_IRUSR) == 0)
375 u[i++] = 'r';
376 if ((mask & S_IWUSR) == 0)
377 u[i++] = 'w';
378 if ((mask & S_IXUSR) == 0)
379 u[i++] = 'x';
380 u[i] = '\0';
381
382 i = 0;
383 if ((mask & S_IRGRP) == 0)
384 g[i++] = 'r';
385 if ((mask & S_IWGRP) == 0)
386 g[i++] = 'w';
387 if ((mask & S_IXGRP) == 0)
388 g[i++] = 'x';
389 g[i] = '\0';
390
391 i = 0;
392 if ((mask & S_IROTH) == 0)
393 o[i++] = 'r';
394 if ((mask & S_IWOTH) == 0)
395 o[i++] = 'w';
396 if ((mask & S_IXOTH) == 0)
397 o[i++] = 'x';
398 o[i] = '\0';
399
400 out1fmt("u=%s,g=%s,o=%s\n", u, g, o);
401 } else {
402 out1fmt("%.4o\n", mask);
403 }
404 } else {
405 if (is_digit(*ap)) {
406 mask = 0;
407 do {
408 if (*ap >= '8' || *ap < '0')
409 error("Illegal number: %s", *argptr);
410 mask = (mask << 3) + (*ap - '0');
411 } while (*++ap != '\0');
412 umask(mask);
413 } else {
414 void *set;
415 INTOFF;
416 if ((set = setmode (ap)) == NULL)
417 error("Illegal number: %s", ap);
418
419 mask = getmode (set, ~mask & 0777);
420 umask(~mask & 0777);
421 free(set);
422 INTON;
423 }
424 }
425 return 0;
426 }
427
428 /*
429 * ulimit builtin
430 *
431 * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and
432 * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with
433 * ash by J.T. Conklin.
434 *
435 * Public domain.
436 */
437
438 struct limits {
439 const char *name;
440 const char *units;
441 int cmd;
442 int factor; /* multiply by to get rlim_{cur,max} values */
443 char option;
444 };
445
446 static const struct limits limits[] = {
447 #ifdef RLIMIT_CPU
448 { "cpu time", "seconds", RLIMIT_CPU, 1, 't' },
449 #endif
450 #ifdef RLIMIT_FSIZE
451 { "file size", "512-blocks", RLIMIT_FSIZE, 512, 'f' },
452 #endif
453 #ifdef RLIMIT_DATA
454 { "data seg size", "kbytes", RLIMIT_DATA, 1024, 'd' },
455 #endif
456 #ifdef RLIMIT_STACK
457 { "stack size", "kbytes", RLIMIT_STACK, 1024, 's' },
458 #endif
459 #ifdef RLIMIT_CORE
460 { "core file size", "512-blocks", RLIMIT_CORE, 512, 'c' },
461 #endif
462 #ifdef RLIMIT_RSS
463 { "max memory size", "kbytes", RLIMIT_RSS, 1024, 'm' },
464 #endif
465 #ifdef RLIMIT_MEMLOCK
466 { "locked memory", "kbytes", RLIMIT_MEMLOCK, 1024, 'l' },
467 #endif
468 #ifdef RLIMIT_NPROC
469 { "max user processes", (char *)0, RLIMIT_NPROC, 1, 'u' },
470 #endif
471 #ifdef RLIMIT_NOFILE
472 { "open files", (char *)0, RLIMIT_NOFILE, 1, 'n' },
473 #endif
474 #ifdef RLIMIT_VMEM
475 { "virtual mem size", "kbytes", RLIMIT_VMEM, 1024, 'v' },
476 #endif
477 #ifdef RLIMIT_SWAP
478 { "swap limit", "kbytes", RLIMIT_SWAP, 1024, 'w' },
479 #endif
480 #ifdef RLIMIT_SBSIZE
481 { "socket buffer size", "bytes", RLIMIT_SBSIZE, 1, 'b' },
482 #endif
483 #ifdef RLIMIT_NPTS
484 { "pseudo-terminals", (char *)0, RLIMIT_NPTS, 1, 'p' },
485 #endif
486 #ifdef RLIMIT_KQUEUES
487 { "kqueues", (char *)0, RLIMIT_KQUEUES, 1, 'k' },
488 #endif
489 #ifdef RLIMIT_UMTXP
490 { "umtx shared locks", (char *)0, RLIMIT_UMTXP, 1, 'o' },
491 #endif
492 { (char *) 0, (char *)0, 0, 0, '\0' }
493 };
494
495 enum limithow { SOFT = 0x1, HARD = 0x2 };
496
497 static void
printlimit(enum limithow how,const struct rlimit * limit,const struct limits * l)498 printlimit(enum limithow how, const struct rlimit *limit,
499 const struct limits *l)
500 {
501 rlim_t val = 0;
502
503 if (how & SOFT)
504 val = limit->rlim_cur;
505 else if (how & HARD)
506 val = limit->rlim_max;
507 if (val == RLIM_INFINITY)
508 out1str("unlimited\n");
509 else
510 {
511 val /= l->factor;
512 out1fmt("%jd\n", (intmax_t)val);
513 }
514 }
515
516 int
ulimitcmd(int argc __unused,char ** argv __unused)517 ulimitcmd(int argc __unused, char **argv __unused)
518 {
519 rlim_t val = 0;
520 enum limithow how = SOFT | HARD;
521 const struct limits *l;
522 int set, all = 0;
523 int optc, what;
524 struct rlimit limit;
525
526 what = 'f';
527 while ((optc = nextopt("HSatfdsmcnuvlbpwko")) != '\0')
528 switch (optc) {
529 case 'H':
530 how = HARD;
531 break;
532 case 'S':
533 how = SOFT;
534 break;
535 case 'a':
536 all = 1;
537 break;
538 default:
539 what = optc;
540 }
541
542 for (l = limits; l->name && l->option != what; l++)
543 ;
544 if (!l->name)
545 error("internal error (%c)", what);
546
547 set = *argptr ? 1 : 0;
548 if (set) {
549 char *p = *argptr;
550
551 if (all || argptr[1])
552 error("too many arguments");
553 if (strcmp(p, "unlimited") == 0)
554 val = RLIM_INFINITY;
555 else {
556 char *end;
557 uintmax_t uval;
558
559 if (*p < '0' || *p > '9')
560 error("bad number");
561 errno = 0;
562 uval = strtoumax(p, &end, 10);
563 if (errno != 0 || *end != '\0')
564 error("bad number");
565 if (uval > UINTMAX_MAX / l->factor)
566 error("bad number");
567 uval *= l->factor;
568 val = (rlim_t)uval;
569 if (val < 0 || (uintmax_t)val != uval ||
570 val == RLIM_INFINITY)
571 error("bad number");
572 }
573 }
574 if (all) {
575 for (l = limits; l->name; l++) {
576 char optbuf[40];
577 if (getrlimit(l->cmd, &limit) < 0)
578 error("can't get limit: %s", strerror(errno));
579
580 if (l->units)
581 snprintf(optbuf, sizeof(optbuf),
582 "(%s, -%c) ", l->units, l->option);
583 else
584 snprintf(optbuf, sizeof(optbuf),
585 "(-%c) ", l->option);
586 out1fmt("%-18s %18s ", l->name, optbuf);
587 printlimit(how, &limit, l);
588 }
589 return 0;
590 }
591
592 if (getrlimit(l->cmd, &limit) < 0)
593 error("can't get limit: %s", strerror(errno));
594 if (set) {
595 if (how & SOFT)
596 limit.rlim_cur = val;
597 if (how & HARD)
598 limit.rlim_max = val;
599 if (setrlimit(l->cmd, &limit) < 0)
600 error("bad limit: %s", strerror(errno));
601 } else
602 printlimit(how, &limit, l);
603 return 0;
604 }
605