xref: /freebsd/bin/sh/miscbltin.c (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
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 int readcmd(int, char **);
70 int umaskcmd(int, char **);
71 int ulimitcmd(int, char **);
72 
73 /*
74  * The read builtin.  The -r option causes backslashes to be treated like
75  * ordinary characters.
76  *
77  * This uses unbuffered input, which may be avoidable in some cases.
78  *
79  * Note that if IFS=' :' then read x y should work so that:
80  * 'a b'	x='a', y='b'
81  * ' a b '	x='a', y='b'
82  * ':b'		x='',  y='b'
83  * ':'		x='',  y=''
84  * '::'		x='',  y=''
85  * ': :'	x='',  y=''
86  * ':::'	x='',  y='::'
87  * ':b c:'	x='',  y='b c:'
88  */
89 
90 int
91 readcmd(int argc __unused, char **argv __unused)
92 {
93 	char **ap;
94 	int backslash;
95 	char c;
96 	int rflag;
97 	char *prompt;
98 	const char *ifs;
99 	char *p;
100 	int startword;
101 	int status;
102 	int i;
103 	int is_ifs;
104 	int saveall = 0;
105 	ptrdiff_t lastnonifs, lastnonifsws;
106 	struct timeval tv;
107 	char *tvptr;
108 	fd_set ifds;
109 	ssize_t nread;
110 	int sig;
111 
112 	rflag = 0;
113 	prompt = NULL;
114 	tv.tv_sec = -1;
115 	tv.tv_usec = 0;
116 	while ((i = nextopt("erp:t:")) != '\0') {
117 		switch(i) {
118 		case 'p':
119 			prompt = shoptarg;
120 			break;
121 		case 'e':
122 			break;
123 		case 'r':
124 			rflag = 1;
125 			break;
126 		case 't':
127 			tv.tv_sec = strtol(shoptarg, &tvptr, 0);
128 			if (tvptr == shoptarg)
129 				error("timeout value");
130 			switch(*tvptr) {
131 			case 0:
132 			case 's':
133 				break;
134 			case 'h':
135 				tv.tv_sec *= 60;
136 				/* FALLTHROUGH */
137 			case 'm':
138 				tv.tv_sec *= 60;
139 				break;
140 			default:
141 				error("timeout unit");
142 			}
143 			break;
144 		}
145 	}
146 	if (prompt && isatty(0)) {
147 		out2str(prompt);
148 		flushall();
149 	}
150 	if (*(ap = argptr) == NULL)
151 		error("arg count");
152 	if ((ifs = bltinlookup("IFS", 1)) == NULL)
153 		ifs = " \t\n";
154 
155 	if (tv.tv_sec >= 0) {
156 		/*
157 		 * Wait for something to become available.
158 		 */
159 		FD_ZERO(&ifds);
160 		FD_SET(0, &ifds);
161 		status = select(1, &ifds, NULL, NULL, &tv);
162 		/*
163 		 * If there's nothing ready, return an error.
164 		 */
165 		if (status <= 0) {
166 			sig = pendingsig;
167 			return (128 + (sig != 0 ? sig : SIGALRM));
168 		}
169 	}
170 
171 	status = 0;
172 	startword = 2;
173 	backslash = 0;
174 	STARTSTACKSTR(p);
175 	lastnonifs = lastnonifsws = -1;
176 	for (;;) {
177 		nread = read(STDIN_FILENO, &c, 1);
178 		if (nread == -1) {
179 			if (errno == EINTR) {
180 				sig = pendingsig;
181 				if (sig == 0)
182 					continue;
183 				status = 128 + sig;
184 				break;
185 			}
186 			warning("read error: %s", strerror(errno));
187 			status = 2;
188 			break;
189 		} else if (nread != 1) {
190 			status = 1;
191 			break;
192 		}
193 		if (c == '\0')
194 			continue;
195 		CHECKSTRSPACE(1, p);
196 		if (backslash) {
197 			backslash = 0;
198 			if (c != '\n') {
199 				startword = 0;
200 				lastnonifs = lastnonifsws = p - stackblock();
201 				USTPUTC(c, p);
202 			}
203 			continue;
204 		}
205 		if (!rflag && c == '\\') {
206 			backslash++;
207 			continue;
208 		}
209 		if (c == '\n')
210 			break;
211 		if (strchr(ifs, c))
212 			is_ifs = strchr(" \t\n", c) ? 1 : 2;
213 		else
214 			is_ifs = 0;
215 
216 		if (startword != 0) {
217 			if (is_ifs == 1) {
218 				/* Ignore leading IFS whitespace */
219 				if (saveall)
220 					USTPUTC(c, p);
221 				continue;
222 			}
223 			if (is_ifs == 2 && startword == 1) {
224 				/* Only one non-whitespace IFS per word */
225 				startword = 2;
226 				if (saveall) {
227 					lastnonifsws = p - stackblock();
228 					USTPUTC(c, p);
229 				}
230 				continue;
231 			}
232 		}
233 
234 		if (is_ifs == 0) {
235 			/* append this character to the current variable */
236 			startword = 0;
237 			if (saveall)
238 				/* Not just a spare terminator */
239 				saveall++;
240 			lastnonifs = lastnonifsws = p - stackblock();
241 			USTPUTC(c, p);
242 			continue;
243 		}
244 
245 		/* end of variable... */
246 		startword = is_ifs;
247 
248 		if (ap[1] == NULL) {
249 			/* Last variable needs all IFS chars */
250 			saveall++;
251 			if (is_ifs == 2)
252 				lastnonifsws = p - stackblock();
253 			USTPUTC(c, p);
254 			continue;
255 		}
256 
257 		STACKSTRNUL(p);
258 		setvar(*ap, stackblock(), 0);
259 		ap++;
260 		STARTSTACKSTR(p);
261 		lastnonifs = lastnonifsws = -1;
262 	}
263 	STACKSTRNUL(p);
264 
265 	/*
266 	 * Remove trailing IFS chars: always remove whitespace, don't remove
267 	 * non-whitespace unless it was naked
268 	 */
269 	if (saveall <= 1)
270 		lastnonifsws = lastnonifs;
271 	stackblock()[lastnonifsws + 1] = '\0';
272 	setvar(*ap, stackblock(), 0);
273 
274 	/* Set any remaining args to "" */
275 	while (*++ap != NULL)
276 		setvar(*ap, "", 0);
277 	return status;
278 }
279 
280 
281 
282 int
283 umaskcmd(int argc __unused, char **argv __unused)
284 {
285 	char *ap;
286 	int mask;
287 	int i;
288 	int symbolic_mode = 0;
289 
290 	while ((i = nextopt("S")) != '\0') {
291 		symbolic_mode = 1;
292 	}
293 
294 	INTOFF;
295 	mask = umask(0);
296 	umask(mask);
297 	INTON;
298 
299 	if ((ap = *argptr) == NULL) {
300 		if (symbolic_mode) {
301 			char u[4], g[4], o[4];
302 
303 			i = 0;
304 			if ((mask & S_IRUSR) == 0)
305 				u[i++] = 'r';
306 			if ((mask & S_IWUSR) == 0)
307 				u[i++] = 'w';
308 			if ((mask & S_IXUSR) == 0)
309 				u[i++] = 'x';
310 			u[i] = '\0';
311 
312 			i = 0;
313 			if ((mask & S_IRGRP) == 0)
314 				g[i++] = 'r';
315 			if ((mask & S_IWGRP) == 0)
316 				g[i++] = 'w';
317 			if ((mask & S_IXGRP) == 0)
318 				g[i++] = 'x';
319 			g[i] = '\0';
320 
321 			i = 0;
322 			if ((mask & S_IROTH) == 0)
323 				o[i++] = 'r';
324 			if ((mask & S_IWOTH) == 0)
325 				o[i++] = 'w';
326 			if ((mask & S_IXOTH) == 0)
327 				o[i++] = 'x';
328 			o[i] = '\0';
329 
330 			out1fmt("u=%s,g=%s,o=%s\n", u, g, o);
331 		} else {
332 			out1fmt("%.4o\n", mask);
333 		}
334 	} else {
335 		if (is_digit(*ap)) {
336 			mask = 0;
337 			do {
338 				if (*ap >= '8' || *ap < '0')
339 					error("Illegal number: %s", *argptr);
340 				mask = (mask << 3) + (*ap - '0');
341 			} while (*++ap != '\0');
342 			umask(mask);
343 		} else {
344 			void *set;
345 			INTOFF;
346 			if ((set = setmode (ap)) == NULL)
347 				error("Illegal number: %s", ap);
348 
349 			mask = getmode (set, ~mask & 0777);
350 			umask(~mask & 0777);
351 			free(set);
352 			INTON;
353 		}
354 	}
355 	return 0;
356 }
357 
358 /*
359  * ulimit builtin
360  *
361  * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and
362  * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with
363  * ash by J.T. Conklin.
364  *
365  * Public domain.
366  */
367 
368 struct limits {
369 	const char *name;
370 	const char *units;
371 	int	cmd;
372 	short	factor;	/* multiply by to get rlim_{cur,max} values */
373 	char	option;
374 };
375 
376 static const struct limits limits[] = {
377 #ifdef RLIMIT_CPU
378 	{ "cpu time",		"seconds",	RLIMIT_CPU,	   1, 't' },
379 #endif
380 #ifdef RLIMIT_FSIZE
381 	{ "file size",		"512-blocks",	RLIMIT_FSIZE,	 512, 'f' },
382 #endif
383 #ifdef RLIMIT_DATA
384 	{ "data seg size",	"kbytes",	RLIMIT_DATA,	1024, 'd' },
385 #endif
386 #ifdef RLIMIT_STACK
387 	{ "stack size",		"kbytes",	RLIMIT_STACK,	1024, 's' },
388 #endif
389 #ifdef  RLIMIT_CORE
390 	{ "core file size",	"512-blocks",	RLIMIT_CORE,	 512, 'c' },
391 #endif
392 #ifdef RLIMIT_RSS
393 	{ "max memory size",	"kbytes",	RLIMIT_RSS,	1024, 'm' },
394 #endif
395 #ifdef RLIMIT_MEMLOCK
396 	{ "locked memory",	"kbytes",	RLIMIT_MEMLOCK, 1024, 'l' },
397 #endif
398 #ifdef RLIMIT_NPROC
399 	{ "max user processes",	(char *)0,	RLIMIT_NPROC,      1, 'u' },
400 #endif
401 #ifdef RLIMIT_NOFILE
402 	{ "open files",		(char *)0,	RLIMIT_NOFILE,     1, 'n' },
403 #endif
404 #ifdef RLIMIT_VMEM
405 	{ "virtual mem size",	"kbytes",	RLIMIT_VMEM,	1024, 'v' },
406 #endif
407 #ifdef RLIMIT_SWAP
408 	{ "swap limit",		"kbytes",	RLIMIT_SWAP,	1024, 'w' },
409 #endif
410 #ifdef RLIMIT_SBSIZE
411 	{ "socket buffer size",	"bytes",	RLIMIT_SBSIZE,	   1, 'b' },
412 #endif
413 #ifdef RLIMIT_NPTS
414 	{ "pseudo-terminals",	(char *)0,	RLIMIT_NPTS,	   1, 'p' },
415 #endif
416 #ifdef RLIMIT_KQUEUES
417 	{ "kqueues",		(char *)0,	RLIMIT_KQUEUES,	   1, 'k' },
418 #endif
419 #ifdef RLIMIT_UMTXP
420 	{ "umtx shared locks",	(char *)0,	RLIMIT_UMTXP,	   1, 'o' },
421 #endif
422 	{ (char *) 0,		(char *)0,	0,		   0, '\0' }
423 };
424 
425 enum limithow { SOFT = 0x1, HARD = 0x2 };
426 
427 static void
428 printlimit(enum limithow how, const struct rlimit *limit,
429     const struct limits *l)
430 {
431 	rlim_t val = 0;
432 
433 	if (how & SOFT)
434 		val = limit->rlim_cur;
435 	else if (how & HARD)
436 		val = limit->rlim_max;
437 	if (val == RLIM_INFINITY)
438 		out1str("unlimited\n");
439 	else
440 	{
441 		val /= l->factor;
442 		out1fmt("%jd\n", (intmax_t)val);
443 	}
444 }
445 
446 int
447 ulimitcmd(int argc __unused, char **argv __unused)
448 {
449 	rlim_t val = 0;
450 	enum limithow how = SOFT | HARD;
451 	const struct limits	*l;
452 	int		set, all = 0;
453 	int		optc, what;
454 	struct rlimit	limit;
455 
456 	what = 'f';
457 	while ((optc = nextopt("HSatfdsmcnuvlbpwko")) != '\0')
458 		switch (optc) {
459 		case 'H':
460 			how = HARD;
461 			break;
462 		case 'S':
463 			how = SOFT;
464 			break;
465 		case 'a':
466 			all = 1;
467 			break;
468 		default:
469 			what = optc;
470 		}
471 
472 	for (l = limits; l->name && l->option != what; l++)
473 		;
474 	if (!l->name)
475 		error("internal error (%c)", what);
476 
477 	set = *argptr ? 1 : 0;
478 	if (set) {
479 		char *p = *argptr;
480 
481 		if (all || argptr[1])
482 			error("too many arguments");
483 		if (strcmp(p, "unlimited") == 0)
484 			val = RLIM_INFINITY;
485 		else {
486 			char *end;
487 			uintmax_t uval;
488 
489 			if (*p < '0' || *p > '9')
490 				error("bad number");
491 			errno = 0;
492 			uval = strtoumax(p, &end, 10);
493 			if (errno != 0 || *end != '\0')
494 				error("bad number");
495 			if (uval > UINTMAX_MAX / l->factor)
496 				error("bad number");
497 			uval *= l->factor;
498 			val = (rlim_t)uval;
499 			if (val < 0 || (uintmax_t)val != uval ||
500 			    val == RLIM_INFINITY)
501 				error("bad number");
502 		}
503 	}
504 	if (all) {
505 		for (l = limits; l->name; l++) {
506 			char optbuf[40];
507 			if (getrlimit(l->cmd, &limit) < 0)
508 				error("can't get limit: %s", strerror(errno));
509 
510 			if (l->units)
511 				snprintf(optbuf, sizeof(optbuf),
512 					"(%s, -%c) ", l->units, l->option);
513 			else
514 				snprintf(optbuf, sizeof(optbuf),
515 					"(-%c) ", l->option);
516 			out1fmt("%-18s %18s ", l->name, optbuf);
517 			printlimit(how, &limit, l);
518 		}
519 		return 0;
520 	}
521 
522 	if (getrlimit(l->cmd, &limit) < 0)
523 		error("can't get limit: %s", strerror(errno));
524 	if (set) {
525 		if (how & SOFT)
526 			limit.rlim_cur = val;
527 		if (how & HARD)
528 			limit.rlim_max = val;
529 		if (setrlimit(l->cmd, &limit) < 0)
530 			error("bad limit: %s", strerror(errno));
531 	} else
532 		printlimit(how, &limit, l);
533 	return 0;
534 }
535