xref: /freebsd/bin/sh/options.c (revision ccfb965433c67f3bda935a3cdf334be2e3c4348d)
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[] = "@(#)options.c	8.2 (Berkeley) 5/4/95";
36 #endif
37 #endif /* not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include <signal.h>
42 #include <unistd.h>
43 #include <stdlib.h>
44 
45 #include "shell.h"
46 #define DEFINE_OPTIONS
47 #include "options.h"
48 #undef DEFINE_OPTIONS
49 #include "nodes.h"	/* for other header files */
50 #include "eval.h"
51 #include "jobs.h"
52 #include "input.h"
53 #include "output.h"
54 #include "trap.h"
55 #include "var.h"
56 #include "memalloc.h"
57 #include "error.h"
58 #include "mystring.h"
59 #include "builtins.h"
60 #ifndef NO_HISTORY
61 #include "myhistedit.h"
62 #endif
63 
64 char *arg0;			/* value of $0 */
65 struct shparam shellparam;	/* current positional parameters */
66 char **argptr;			/* argument list for builtin commands */
67 char *shoptarg;			/* set by nextopt (like getopt) */
68 char *nextopt_optptr;		/* used by nextopt */
69 
70 char *minusc;			/* argument to -c option */
71 
72 
73 static void options(int);
74 static void minus_o(char *, int);
75 static void setoption(int, int);
76 static int getopts(char *, char *, char **, char ***, char **);
77 
78 
79 /*
80  * Process the shell command line arguments.
81  */
82 
83 void
84 procargs(int argc, char **argv)
85 {
86 	int i;
87 	char *scriptname;
88 
89 	argptr = argv;
90 	if (argc > 0)
91 		argptr++;
92 	for (i = 0; i < NOPTS; i++)
93 		optlist[i].val = 2;
94 	privileged = (getuid() != geteuid() || getgid() != getegid());
95 	options(1);
96 	if (*argptr == NULL && minusc == NULL)
97 		sflag = 1;
98 	if (iflag != 0 && sflag == 1 && isatty(0) && isatty(1)) {
99 		iflag = 1;
100 		if (Eflag == 2)
101 			Eflag = 1;
102 	}
103 	if (mflag == 2)
104 		mflag = iflag;
105 	for (i = 0; i < NOPTS; i++)
106 		if (optlist[i].val == 2)
107 			optlist[i].val = 0;
108 	arg0 = argv[0];
109 	if (sflag == 0 && minusc == NULL) {
110 		scriptname = *argptr++;
111 		setinputfile(scriptname, 0);
112 		commandname = arg0 = scriptname;
113 	}
114 	/* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
115 	if (argptr && minusc && *argptr)
116 		arg0 = *argptr++;
117 
118 	shellparam.p = argptr;
119 	shellparam.reset = 1;
120 	/* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
121 	while (*argptr) {
122 		shellparam.nparam++;
123 		argptr++;
124 	}
125 	optschanged();
126 }
127 
128 
129 void
130 optschanged(void)
131 {
132 	setinteractive(iflag);
133 #ifndef NO_HISTORY
134 	histedit();
135 #endif
136 	setjobctl(mflag);
137 }
138 
139 /*
140  * Process shell options.  The global variable argptr contains a pointer
141  * to the argument list; we advance it past the options.
142  */
143 
144 static void
145 options(int cmdline)
146 {
147 	char *kp, *p;
148 	int val;
149 	int c;
150 
151 	if (cmdline)
152 		minusc = NULL;
153 	while ((p = *argptr) != NULL) {
154 		argptr++;
155 		if ((c = *p++) == '-') {
156 			val = 1;
157 			/* A "-" or  "--" terminates options */
158 			if (p[0] == '\0')
159 				goto end_options1;
160 			if (p[0] == '-' && p[1] == '\0')
161 				goto end_options2;
162 			/**
163 			 * For the benefit of `#!' lines in shell scripts,
164 			 * treat a string of '-- *#.*' the same as '--'.
165 			 * This is needed so that a script starting with:
166 			 *	#!/bin/sh -- # -*- perl -*-
167 			 * will continue to work after a change is made to
168 			 * kern/imgact_shell.c to NOT token-ize the options
169 			 * specified on a '#!' line.  A bit of a kludge,
170 			 * but that trick is recommended in documentation
171 			 * for some scripting languages, and we might as
172 			 * well continue to support it.
173 			 */
174 			if (p[0] == '-') {
175 				kp = p + 1;
176 				while (*kp == ' ' || *kp == '\t')
177 					kp++;
178 				if (*kp == '#' || *kp == '\0')
179 					goto end_options2;
180 			}
181 		} else if (c == '+') {
182 			val = 0;
183 		} else {
184 			argptr--;
185 			break;
186 		}
187 		while ((c = *p++) != '\0') {
188 			if (c == 'c' && cmdline) {
189 				char *q;
190 #ifdef NOHACK	/* removing this code allows sh -ce 'foo' for compat */
191 				if (*p == '\0')
192 #endif
193 					q = *argptr++;
194 				if (q == NULL || minusc != NULL)
195 					error("Bad -c option");
196 				minusc = q;
197 #ifdef NOHACK
198 				break;
199 #endif
200 			} else if (c == 'o') {
201 				minus_o(*argptr, val);
202 				if (*argptr)
203 					argptr++;
204 			} else
205 				setoption(c, val);
206 		}
207 	}
208 	return;
209 
210 	/* When processing `set', a single "-" means turn off -x and -v */
211 end_options1:
212 	if (!cmdline) {
213 		xflag = vflag = 0;
214 		return;
215 	}
216 
217 	/*
218 	 * When processing `set', a "--" means the remaining arguments
219 	 * replace the positional parameters in the active shell.  If
220 	 * there are no remaining options, then all the positional
221 	 * parameters are cleared (equivalent to doing ``shift $#'').
222 	 */
223 end_options2:
224 	if (!cmdline) {
225 		if (*argptr == NULL)
226 			setparam(argptr);
227 		return;
228 	}
229 
230 	/*
231 	 * At this point we are processing options given to 'sh' on a command
232 	 * line.  If an end-of-options marker ("-" or "--") is followed by an
233 	 * arg of "#", then skip over all remaining arguments.  Some scripting
234 	 * languages (e.g.: perl) document that /bin/sh will implement this
235 	 * behavior, and they recommend that users take advantage of it to
236 	 * solve certain issues that can come up when writing a perl script.
237 	 * Yes, this feature is in /bin/sh to help users write perl scripts.
238 	 */
239 	p = *argptr;
240 	if (p != NULL && p[0] == '#' && p[1] == '\0') {
241 		while (*argptr != NULL)
242 			argptr++;
243 		/* We need to keep the final argument */
244 		argptr--;
245 	}
246 }
247 
248 static void
249 minus_o(char *name, int val)
250 {
251 	int i;
252 
253 	if (name == NULL) {
254 		if (val) {
255 			/* "Pretty" output. */
256 			out1str("Current option settings\n");
257 			for (i = 0; i < NOPTS; i++)
258 				out1fmt("%-16s%s\n", optlist[i].name,
259 					optlist[i].val ? "on" : "off");
260 		} else {
261 			/* Output suitable for re-input to shell. */
262 			for (i = 0; i < NOPTS; i++)
263 				out1fmt("%s %co %s%s",
264 				    i % 6 == 0 ? "set" : "",
265 				    optlist[i].val ? '-' : '+',
266 				    optlist[i].name,
267 				    i % 6 == 5 || i == NOPTS - 1 ? "\n" : "");
268 		}
269 	} else {
270 		for (i = 0; i < NOPTS; i++)
271 			if (equal(name, optlist[i].name)) {
272 				setoption(optlist[i].letter, val);
273 				return;
274 			}
275 		error("Illegal option -o %s", name);
276 	}
277 }
278 
279 
280 static void
281 setoption(int flag, int val)
282 {
283 	int i;
284 
285 	if (flag == 'p' && !val && privileged) {
286 		if (setgid(getgid()) == -1)
287 			error("setgid");
288 		if (setuid(getuid()) == -1)
289 			error("setuid");
290 	}
291 	for (i = 0; i < NOPTS; i++)
292 		if (optlist[i].letter == flag) {
293 			optlist[i].val = val;
294 			if (val) {
295 				/* #%$ hack for ksh semantics */
296 				if (flag == 'V')
297 					Eflag = 0;
298 				else if (flag == 'E')
299 					Vflag = 0;
300 			}
301 			return;
302 		}
303 	error("Illegal option -%c", flag);
304 }
305 
306 
307 /*
308  * Set the shell parameters.
309  */
310 
311 void
312 setparam(char **argv)
313 {
314 	char **newparam;
315 	char **ap;
316 	int nparam;
317 
318 	for (nparam = 0 ; argv[nparam] ; nparam++);
319 	ap = newparam = ckmalloc((nparam + 1) * sizeof *ap);
320 	while (*argv) {
321 		*ap++ = savestr(*argv++);
322 	}
323 	*ap = NULL;
324 	freeparam(&shellparam);
325 	shellparam.malloc = 1;
326 	shellparam.nparam = nparam;
327 	shellparam.p = newparam;
328 	shellparam.optp = NULL;
329 	shellparam.reset = 1;
330 	shellparam.optnext = NULL;
331 }
332 
333 
334 /*
335  * Free the list of positional parameters.
336  */
337 
338 void
339 freeparam(struct shparam *param)
340 {
341 	char **ap;
342 
343 	if (param->malloc) {
344 		for (ap = param->p ; *ap ; ap++)
345 			ckfree(*ap);
346 		ckfree(param->p);
347 	}
348 	if (param->optp) {
349 		for (ap = param->optp ; *ap ; ap++)
350 			ckfree(*ap);
351 		ckfree(param->optp);
352 	}
353 }
354 
355 
356 
357 /*
358  * The shift builtin command.
359  */
360 
361 int
362 shiftcmd(int argc, char **argv)
363 {
364 	int n;
365 	char **ap1, **ap2;
366 
367 	n = 1;
368 	if (argc > 1)
369 		n = number(argv[1]);
370 	if (n > shellparam.nparam)
371 		return 1;
372 	INTOFF;
373 	shellparam.nparam -= n;
374 	for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
375 		if (shellparam.malloc)
376 			ckfree(*ap1);
377 	}
378 	ap2 = shellparam.p;
379 	while ((*ap2++ = *ap1++) != NULL);
380 	shellparam.reset = 1;
381 	INTON;
382 	return 0;
383 }
384 
385 
386 
387 /*
388  * The set command builtin.
389  */
390 
391 int
392 setcmd(int argc, char **argv)
393 {
394 	if (argc == 1)
395 		return showvarscmd(argc, argv);
396 	INTOFF;
397 	options(0);
398 	optschanged();
399 	if (*argptr != NULL) {
400 		setparam(argptr);
401 	}
402 	INTON;
403 	return 0;
404 }
405 
406 
407 void
408 getoptsreset(const char *value)
409 {
410 	while (*value == '0')
411 		value++;
412 	if (strcmp(value, "1") == 0)
413 		shellparam.reset = 1;
414 }
415 
416 /*
417  * The getopts builtin.  Shellparam.optnext points to the next argument
418  * to be processed.  Shellparam.optptr points to the next character to
419  * be processed in the current argument.  If shellparam.optnext is NULL,
420  * then it's the first time getopts has been called.
421  */
422 
423 int
424 getoptscmd(int argc, char **argv)
425 {
426 	char **optbase = NULL, **ap;
427 	int i;
428 
429 	if (argc < 3)
430 		error("usage: getopts optstring var [arg]");
431 
432 	if (shellparam.reset == 1) {
433 		INTOFF;
434 		if (shellparam.optp) {
435 			for (ap = shellparam.optp ; *ap ; ap++)
436 				ckfree(*ap);
437 			ckfree(shellparam.optp);
438 			shellparam.optp = NULL;
439 		}
440 		if (argc > 3) {
441 			shellparam.optp = ckmalloc((argc - 2) * sizeof *ap);
442 			memset(shellparam.optp, '\0', (argc - 2) * sizeof *ap);
443 			for (i = 0; i < argc - 3; i++)
444 				shellparam.optp[i] = savestr(argv[i + 3]);
445 		}
446 		INTON;
447 		optbase = argc == 3 ? shellparam.p : shellparam.optp;
448 		shellparam.optnext = optbase;
449 		shellparam.optptr = NULL;
450 		shellparam.reset = 0;
451 	} else
452 		optbase = shellparam.optp ? shellparam.optp : shellparam.p;
453 
454 	return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
455 		       &shellparam.optptr);
456 }
457 
458 static int
459 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
460     char **optptr)
461 {
462 	char *p, *q;
463 	char c = '?';
464 	int done = 0;
465 	int ind = 0;
466 	int err = 0;
467 	char s[10];
468 	const char *newoptarg = NULL;
469 
470 	if ((p = *optptr) == NULL || *p == '\0') {
471 		/* Current word is done, advance */
472 		if (*optnext == NULL)
473 			return 1;
474 		p = **optnext;
475 		if (p == NULL || *p != '-' || *++p == '\0') {
476 atend:
477 			ind = *optnext - optfirst + 1;
478 			*optnext = NULL;
479 			p = NULL;
480 			done = 1;
481 			goto out;
482 		}
483 		(*optnext)++;
484 		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
485 			goto atend;
486 	}
487 
488 	c = *p++;
489 	for (q = optstr; *q != c; ) {
490 		if (*q == '\0') {
491 			if (optstr[0] == ':') {
492 				s[0] = c;
493 				s[1] = '\0';
494 				newoptarg = s;
495 			}
496 			else
497 				out2fmt_flush("Illegal option -%c\n", c);
498 			c = '?';
499 			goto out;
500 		}
501 		if (*++q == ':')
502 			q++;
503 	}
504 
505 	if (*++q == ':') {
506 		if (*p == '\0' && (p = **optnext) == NULL) {
507 			if (optstr[0] == ':') {
508 				s[0] = c;
509 				s[1] = '\0';
510 				newoptarg = s;
511 				c = ':';
512 			}
513 			else {
514 				out2fmt_flush("No arg for -%c option\n", c);
515 				c = '?';
516 			}
517 			goto out;
518 		}
519 
520 		if (p == **optnext)
521 			(*optnext)++;
522 		newoptarg = p;
523 		p = NULL;
524 	}
525 
526 out:
527 	if (*optnext != NULL)
528 		ind = *optnext - optfirst + 1;
529 	*optptr = p;
530 	if (newoptarg != NULL)
531 		err |= setvarsafe("OPTARG", newoptarg, 0);
532 	else {
533 		INTOFF;
534 		err |= unsetvar("OPTARG");
535 		INTON;
536 	}
537 	fmtstr(s, sizeof(s), "%d", ind);
538 	err |= setvarsafe("OPTIND", s, VNOFUNC);
539 	s[0] = c;
540 	s[1] = '\0';
541 	err |= setvarsafe(optvar, s, 0);
542 	if (err) {
543 		*optnext = NULL;
544 		*optptr = NULL;
545 		flushall();
546 		exraise(EXERROR);
547 	}
548 	return done;
549 }
550 
551 /*
552  * Standard option processing (a la getopt) for builtin routines.  The
553  * only argument that is passed to nextopt is the option string; the
554  * other arguments are unnecessary.  It return the character, or '\0' on
555  * end of input.
556  */
557 
558 int
559 nextopt(const char *optstring)
560 {
561 	char *p;
562 	const char *q;
563 	char c;
564 
565 	if ((p = nextopt_optptr) == NULL || *p == '\0') {
566 		p = *argptr;
567 		if (p == NULL || *p != '-' || *++p == '\0')
568 			return '\0';
569 		argptr++;
570 		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
571 			return '\0';
572 	}
573 	c = *p++;
574 	for (q = optstring ; *q != c ; ) {
575 		if (*q == '\0')
576 			error("Illegal option -%c", c);
577 		if (*++q == ':')
578 			q++;
579 	}
580 	if (*++q == ':') {
581 		if (*p == '\0' && (p = *argptr++) == NULL)
582 			error("No arg for -%c option", c);
583 		shoptarg = p;
584 		p = NULL;
585 	}
586 	nextopt_optptr = p;
587 	return c;
588 }
589