xref: /freebsd/bin/sh/miscbltin.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
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 int readcmd(int, char **);
68 int umaskcmd(int, char **);
69 int ulimitcmd(int, char **);
70 
71 /*
72  * The read builtin.  The -r option causes backslashes to be treated like
73  * ordinary characters.
74  *
75  * This uses unbuffered input, which may be avoidable in some cases.
76  *
77  * Note that if IFS=' :' then read x y should work so that:
78  * 'a b'	x='a', y='b'
79  * ' a b '	x='a', y='b'
80  * ':b'		x='',  y='b'
81  * ':'		x='',  y=''
82  * '::'		x='',  y=''
83  * ': :'	x='',  y=''
84  * ':::'	x='',  y='::'
85  * ':b c:'	x='',  y='b c:'
86  */
87 
88 int
89 readcmd(int argc __unused, char **argv __unused)
90 {
91 	char **ap;
92 	int backslash;
93 	char c;
94 	int rflag;
95 	char *prompt;
96 	const char *ifs;
97 	char *p;
98 	int startword;
99 	int status;
100 	int i;
101 	int is_ifs;
102 	int saveall = 0;
103 	ptrdiff_t lastnonifs, lastnonifsws;
104 	struct timeval tv;
105 	char *tvptr;
106 	fd_set ifds;
107 	ssize_t nread;
108 	int sig;
109 
110 	rflag = 0;
111 	prompt = NULL;
112 	tv.tv_sec = -1;
113 	tv.tv_usec = 0;
114 	while ((i = nextopt("erp:t:")) != '\0') {
115 		switch(i) {
116 		case 'p':
117 			prompt = shoptarg;
118 			break;
119 		case 'e':
120 			break;
121 		case 'r':
122 			rflag = 1;
123 			break;
124 		case 't':
125 			tv.tv_sec = strtol(shoptarg, &tvptr, 0);
126 			if (tvptr == shoptarg)
127 				error("timeout value");
128 			switch(*tvptr) {
129 			case 0:
130 			case 's':
131 				break;
132 			case 'h':
133 				tv.tv_sec *= 60;
134 				/* FALLTHROUGH */
135 			case 'm':
136 				tv.tv_sec *= 60;
137 				break;
138 			default:
139 				error("timeout unit");
140 			}
141 			break;
142 		}
143 	}
144 	if (prompt && isatty(0)) {
145 		out2str(prompt);
146 		flushall();
147 	}
148 	if (*(ap = argptr) == NULL)
149 		error("arg count");
150 	if ((ifs = bltinlookup("IFS", 1)) == NULL)
151 		ifs = " \t\n";
152 
153 	if (tv.tv_sec >= 0) {
154 		/*
155 		 * Wait for something to become available.
156 		 */
157 		FD_ZERO(&ifds);
158 		FD_SET(0, &ifds);
159 		status = select(1, &ifds, NULL, NULL, &tv);
160 		/*
161 		 * If there's nothing ready, return an error.
162 		 */
163 		if (status <= 0) {
164 			sig = pendingsig;
165 			return (128 + (sig != 0 ? sig : SIGALRM));
166 		}
167 	}
168 
169 	status = 0;
170 	startword = 2;
171 	backslash = 0;
172 	STARTSTACKSTR(p);
173 	lastnonifs = lastnonifsws = -1;
174 	for (;;) {
175 		nread = read(STDIN_FILENO, &c, 1);
176 		if (nread == -1) {
177 			if (errno == EINTR) {
178 				sig = pendingsig;
179 				if (sig == 0)
180 					continue;
181 				status = 128 + sig;
182 				break;
183 			}
184 			warning("read error: %s", strerror(errno));
185 			status = 2;
186 			break;
187 		} else if (nread != 1) {
188 			status = 1;
189 			break;
190 		}
191 		if (c == '\0')
192 			continue;
193 		CHECKSTRSPACE(1, p);
194 		if (backslash) {
195 			backslash = 0;
196 			if (c != '\n') {
197 				startword = 0;
198 				lastnonifs = lastnonifsws = p - stackblock();
199 				USTPUTC(c, p);
200 			}
201 			continue;
202 		}
203 		if (!rflag && c == '\\') {
204 			backslash++;
205 			continue;
206 		}
207 		if (c == '\n')
208 			break;
209 		if (strchr(ifs, c))
210 			is_ifs = strchr(" \t\n", c) ? 1 : 2;
211 		else
212 			is_ifs = 0;
213 
214 		if (startword != 0) {
215 			if (is_ifs == 1) {
216 				/* Ignore leading IFS whitespace */
217 				if (saveall)
218 					USTPUTC(c, p);
219 				continue;
220 			}
221 			if (is_ifs == 2 && startword == 1) {
222 				/* Only one non-whitespace IFS per word */
223 				startword = 2;
224 				if (saveall) {
225 					lastnonifsws = p - stackblock();
226 					USTPUTC(c, p);
227 				}
228 				continue;
229 			}
230 		}
231 
232 		if (is_ifs == 0) {
233 			/* append this character to the current variable */
234 			startword = 0;
235 			if (saveall)
236 				/* Not just a spare terminator */
237 				saveall++;
238 			lastnonifs = lastnonifsws = p - stackblock();
239 			USTPUTC(c, p);
240 			continue;
241 		}
242 
243 		/* end of variable... */
244 		startword = is_ifs;
245 
246 		if (ap[1] == NULL) {
247 			/* Last variable needs all IFS chars */
248 			saveall++;
249 			if (is_ifs == 2)
250 				lastnonifsws = p - stackblock();
251 			USTPUTC(c, p);
252 			continue;
253 		}
254 
255 		STACKSTRNUL(p);
256 		setvar(*ap, stackblock(), 0);
257 		ap++;
258 		STARTSTACKSTR(p);
259 		lastnonifs = lastnonifsws = -1;
260 	}
261 	STACKSTRNUL(p);
262 
263 	/*
264 	 * Remove trailing IFS chars: always remove whitespace, don't remove
265 	 * non-whitespace unless it was naked
266 	 */
267 	if (saveall <= 1)
268 		lastnonifsws = lastnonifs;
269 	stackblock()[lastnonifsws + 1] = '\0';
270 	setvar(*ap, stackblock(), 0);
271 
272 	/* Set any remaining args to "" */
273 	while (*++ap != NULL)
274 		setvar(*ap, "", 0);
275 	return status;
276 }
277 
278 
279 
280 int
281 umaskcmd(int argc __unused, char **argv __unused)
282 {
283 	char *ap;
284 	int mask;
285 	int i;
286 	int symbolic_mode = 0;
287 
288 	while ((i = nextopt("S")) != '\0') {
289 		symbolic_mode = 1;
290 	}
291 
292 	INTOFF;
293 	mask = umask(0);
294 	umask(mask);
295 	INTON;
296 
297 	if ((ap = *argptr) == NULL) {
298 		if (symbolic_mode) {
299 			char u[4], g[4], o[4];
300 
301 			i = 0;
302 			if ((mask & S_IRUSR) == 0)
303 				u[i++] = 'r';
304 			if ((mask & S_IWUSR) == 0)
305 				u[i++] = 'w';
306 			if ((mask & S_IXUSR) == 0)
307 				u[i++] = 'x';
308 			u[i] = '\0';
309 
310 			i = 0;
311 			if ((mask & S_IRGRP) == 0)
312 				g[i++] = 'r';
313 			if ((mask & S_IWGRP) == 0)
314 				g[i++] = 'w';
315 			if ((mask & S_IXGRP) == 0)
316 				g[i++] = 'x';
317 			g[i] = '\0';
318 
319 			i = 0;
320 			if ((mask & S_IROTH) == 0)
321 				o[i++] = 'r';
322 			if ((mask & S_IWOTH) == 0)
323 				o[i++] = 'w';
324 			if ((mask & S_IXOTH) == 0)
325 				o[i++] = 'x';
326 			o[i] = '\0';
327 
328 			out1fmt("u=%s,g=%s,o=%s\n", u, g, o);
329 		} else {
330 			out1fmt("%.4o\n", mask);
331 		}
332 	} else {
333 		if (is_digit(*ap)) {
334 			mask = 0;
335 			do {
336 				if (*ap >= '8' || *ap < '0')
337 					error("Illegal number: %s", *argptr);
338 				mask = (mask << 3) + (*ap - '0');
339 			} while (*++ap != '\0');
340 			umask(mask);
341 		} else {
342 			void *set;
343 			INTOFF;
344 			if ((set = setmode (ap)) == 0)
345 				error("Illegal number: %s", ap);
346 
347 			mask = getmode (set, ~mask & 0777);
348 			umask(~mask & 0777);
349 			free(set);
350 			INTON;
351 		}
352 	}
353 	return 0;
354 }
355 
356 /*
357  * ulimit builtin
358  *
359  * This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and
360  * Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with
361  * ash by J.T. Conklin.
362  *
363  * Public domain.
364  */
365 
366 struct limits {
367 	const char *name;
368 	const char *units;
369 	int	cmd;
370 	int	factor;	/* multiply by to get rlim_{cur,max} values */
371 	char	option;
372 };
373 
374 static const struct limits limits[] = {
375 #ifdef RLIMIT_CPU
376 	{ "cpu time",		"seconds",	RLIMIT_CPU,	   1, 't' },
377 #endif
378 #ifdef RLIMIT_FSIZE
379 	{ "file size",		"512-blocks",	RLIMIT_FSIZE,	 512, 'f' },
380 #endif
381 #ifdef RLIMIT_DATA
382 	{ "data seg size",	"kbytes",	RLIMIT_DATA,	1024, 'd' },
383 #endif
384 #ifdef RLIMIT_STACK
385 	{ "stack size",		"kbytes",	RLIMIT_STACK,	1024, 's' },
386 #endif
387 #ifdef  RLIMIT_CORE
388 	{ "core file size",	"512-blocks",	RLIMIT_CORE,	 512, 'c' },
389 #endif
390 #ifdef RLIMIT_RSS
391 	{ "max memory size",	"kbytes",	RLIMIT_RSS,	1024, 'm' },
392 #endif
393 #ifdef RLIMIT_MEMLOCK
394 	{ "locked memory",	"kbytes",	RLIMIT_MEMLOCK, 1024, 'l' },
395 #endif
396 #ifdef RLIMIT_NPROC
397 	{ "max user processes",	(char *)0,	RLIMIT_NPROC,      1, 'u' },
398 #endif
399 #ifdef RLIMIT_NOFILE
400 	{ "open files",		(char *)0,	RLIMIT_NOFILE,     1, 'n' },
401 #endif
402 #ifdef RLIMIT_VMEM
403 	{ "virtual mem size",	"kbytes",	RLIMIT_VMEM,	1024, 'v' },
404 #endif
405 #ifdef RLIMIT_SWAP
406 	{ "swap limit",		"kbytes",	RLIMIT_SWAP,	1024, 'w' },
407 #endif
408 #ifdef RLIMIT_SBSIZE
409 	{ "sbsize",		"bytes",	RLIMIT_SBSIZE,	   1, 'b' },
410 #endif
411 #ifdef RLIMIT_NPTS
412 	{ "pseudo-terminals",	(char *)0,	RLIMIT_NPTS,	   1, 'p' },
413 #endif
414 #ifdef RLIMIT_KQUEUES
415 	{ "kqueues",		(char *)0,	RLIMIT_KQUEUES,	   1, 'k' },
416 #endif
417 	{ (char *) 0,		(char *)0,	0,		   0, '\0' }
418 };
419 
420 enum limithow { SOFT = 0x1, HARD = 0x2 };
421 
422 static void
423 printlimit(enum limithow how, const struct rlimit *limit,
424     const struct limits *l)
425 {
426 	rlim_t val = 0;
427 
428 	if (how & SOFT)
429 		val = limit->rlim_cur;
430 	else if (how & HARD)
431 		val = limit->rlim_max;
432 	if (val == RLIM_INFINITY)
433 		out1str("unlimited\n");
434 	else
435 	{
436 		val /= l->factor;
437 		out1fmt("%jd\n", (intmax_t)val);
438 	}
439 }
440 
441 int
442 ulimitcmd(int argc __unused, char **argv __unused)
443 {
444 	rlim_t val = 0;
445 	enum limithow how = SOFT | HARD;
446 	const struct limits	*l;
447 	int		set, all = 0;
448 	int		optc, what;
449 	struct rlimit	limit;
450 
451 	what = 'f';
452 	while ((optc = nextopt("HSatfdsmcnuvlbpwk")) != '\0')
453 		switch (optc) {
454 		case 'H':
455 			how = HARD;
456 			break;
457 		case 'S':
458 			how = SOFT;
459 			break;
460 		case 'a':
461 			all = 1;
462 			break;
463 		default:
464 			what = optc;
465 		}
466 
467 	for (l = limits; l->name && l->option != what; l++)
468 		;
469 	if (!l->name)
470 		error("internal error (%c)", what);
471 
472 	set = *argptr ? 1 : 0;
473 	if (set) {
474 		char *p = *argptr;
475 
476 		if (all || argptr[1])
477 			error("too many arguments");
478 		if (strcmp(p, "unlimited") == 0)
479 			val = RLIM_INFINITY;
480 		else {
481 			char *end;
482 			uintmax_t uval;
483 
484 			if (*p < '0' || *p > '9')
485 				error("bad number");
486 			errno = 0;
487 			uval = strtoumax(p, &end, 10);
488 			if (errno != 0 || *end != '\0')
489 				error("bad number");
490 			if (uval > UINTMAX_MAX / l->factor)
491 				error("bad number");
492 			uval *= l->factor;
493 			val = (rlim_t)uval;
494 			if (val < 0 || (uintmax_t)val != uval ||
495 			    val == RLIM_INFINITY)
496 				error("bad number");
497 		}
498 	}
499 	if (all) {
500 		for (l = limits; l->name; l++) {
501 			char optbuf[40];
502 			if (getrlimit(l->cmd, &limit) < 0)
503 				error("can't get limit: %s", strerror(errno));
504 
505 			if (l->units)
506 				snprintf(optbuf, sizeof(optbuf),
507 					"(%s, -%c) ", l->units, l->option);
508 			else
509 				snprintf(optbuf, sizeof(optbuf),
510 					"(-%c) ", l->option);
511 			out1fmt("%-18s %18s ", l->name, optbuf);
512 			printlimit(how, &limit, l);
513 		}
514 		return 0;
515 	}
516 
517 	if (getrlimit(l->cmd, &limit) < 0)
518 		error("can't get limit: %s", strerror(errno));
519 	if (set) {
520 		if (how & SOFT)
521 			limit.rlim_cur = val;
522 		if (how & HARD)
523 			limit.rlim_max = val;
524 		if (setrlimit(l->cmd, &limit) < 0)
525 			error("bad limit: %s", strerror(errno));
526 	} else
527 		printlimit(how, &limit, l);
528 	return 0;
529 }
530