xref: /freebsd/bin/sh/options.c (revision 3f0164abf32b9b761e0a2cb4bdca3a8b84f156d4)
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.reset = 1;
329 	shellparam.optnext = NULL;
330 }
331 
332 
333 /*
334  * Free the list of positional parameters.
335  */
336 
337 void
338 freeparam(struct shparam *param)
339 {
340 	char **ap;
341 
342 	if (param->malloc) {
343 		for (ap = param->p ; *ap ; ap++)
344 			ckfree(*ap);
345 		ckfree(param->p);
346 	}
347 }
348 
349 
350 
351 /*
352  * The shift builtin command.
353  */
354 
355 int
356 shiftcmd(int argc, char **argv)
357 {
358 	int n;
359 	char **ap1, **ap2;
360 
361 	n = 1;
362 	if (argc > 1)
363 		n = number(argv[1]);
364 	if (n > shellparam.nparam)
365 		return 1;
366 	INTOFF;
367 	shellparam.nparam -= n;
368 	for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
369 		if (shellparam.malloc)
370 			ckfree(*ap1);
371 	}
372 	ap2 = shellparam.p;
373 	while ((*ap2++ = *ap1++) != NULL);
374 	shellparam.reset = 1;
375 	INTON;
376 	return 0;
377 }
378 
379 
380 
381 /*
382  * The set command builtin.
383  */
384 
385 int
386 setcmd(int argc, char **argv)
387 {
388 	if (argc == 1)
389 		return showvarscmd(argc, argv);
390 	INTOFF;
391 	options(0);
392 	optschanged();
393 	if (*argptr != NULL) {
394 		setparam(argptr);
395 	}
396 	INTON;
397 	return 0;
398 }
399 
400 
401 void
402 getoptsreset(const char *value)
403 {
404 	while (*value == '0')
405 		value++;
406 	if (strcmp(value, "1") == 0)
407 		shellparam.reset = 1;
408 }
409 
410 /*
411  * The getopts builtin.  Shellparam.optnext points to the next argument
412  * to be processed.  Shellparam.optptr points to the next character to
413  * be processed in the current argument.  If shellparam.optnext is NULL,
414  * then it's the first time getopts has been called.
415  */
416 
417 int
418 getoptscmd(int argc, char **argv)
419 {
420 	char **optbase = NULL;
421 
422 	if (argc < 3)
423 		error("usage: getopts optstring var [arg]");
424 	else if (argc == 3)
425 		optbase = shellparam.p;
426 	else
427 		optbase = &argv[3];
428 
429 	if (shellparam.reset == 1) {
430 		shellparam.optnext = optbase;
431 		shellparam.optptr = NULL;
432 		shellparam.reset = 0;
433 	}
434 
435 	return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
436 		       &shellparam.optptr);
437 }
438 
439 static int
440 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
441     char **optptr)
442 {
443 	char *p, *q;
444 	char c = '?';
445 	int done = 0;
446 	int ind = 0;
447 	int err = 0;
448 	char s[10];
449 
450 	if ((p = *optptr) == NULL || *p == '\0') {
451 		/* Current word is done, advance */
452 		if (*optnext == NULL)
453 			return 1;
454 		p = **optnext;
455 		if (p == NULL || *p != '-' || *++p == '\0') {
456 atend:
457 			ind = *optnext - optfirst + 1;
458 			*optnext = NULL;
459 			p = NULL;
460 			done = 1;
461 			goto out;
462 		}
463 		(*optnext)++;
464 		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
465 			goto atend;
466 	}
467 
468 	c = *p++;
469 	for (q = optstr; *q != c; ) {
470 		if (*q == '\0') {
471 			if (optstr[0] == ':') {
472 				s[0] = c;
473 				s[1] = '\0';
474 				err |= setvarsafe("OPTARG", s, 0);
475 			}
476 			else {
477 				out1fmt("Illegal option -%c\n", c);
478 				(void) unsetvar("OPTARG");
479 			}
480 			c = '?';
481 			goto bad;
482 		}
483 		if (*++q == ':')
484 			q++;
485 	}
486 
487 	if (*++q == ':') {
488 		if (*p == '\0' && (p = **optnext) == NULL) {
489 			if (optstr[0] == ':') {
490 				s[0] = c;
491 				s[1] = '\0';
492 				err |= setvarsafe("OPTARG", s, 0);
493 				c = ':';
494 			}
495 			else {
496 				out1fmt("No arg for -%c option\n", c);
497 				(void) unsetvar("OPTARG");
498 				c = '?';
499 			}
500 			goto bad;
501 		}
502 
503 		if (p == **optnext)
504 			(*optnext)++;
505 		setvarsafe("OPTARG", p, 0);
506 		p = NULL;
507 	}
508 	else
509 		setvarsafe("OPTARG", "", 0);
510 	ind = *optnext - optfirst + 1;
511 	goto out;
512 
513 bad:
514 	ind = 1;
515 	*optnext = NULL;
516 	p = NULL;
517 out:
518 	*optptr = p;
519 	fmtstr(s, sizeof(s), "%d", ind);
520 	err |= setvarsafe("OPTIND", s, VNOFUNC);
521 	s[0] = c;
522 	s[1] = '\0';
523 	err |= setvarsafe(optvar, s, 0);
524 	if (err) {
525 		*optnext = NULL;
526 		*optptr = NULL;
527 		flushall();
528 		exraise(EXERROR);
529 	}
530 	return done;
531 }
532 
533 /*
534  * Standard option processing (a la getopt) for builtin routines.  The
535  * only argument that is passed to nextopt is the option string; the
536  * other arguments are unnecessary.  It return the character, or '\0' on
537  * end of input.
538  */
539 
540 int
541 nextopt(const char *optstring)
542 {
543 	char *p;
544 	const char *q;
545 	char c;
546 
547 	if ((p = nextopt_optptr) == NULL || *p == '\0') {
548 		p = *argptr;
549 		if (p == NULL || *p != '-' || *++p == '\0')
550 			return '\0';
551 		argptr++;
552 		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
553 			return '\0';
554 	}
555 	c = *p++;
556 	for (q = optstring ; *q != c ; ) {
557 		if (*q == '\0')
558 			error("Illegal option -%c", c);
559 		if (*++q == ':')
560 			q++;
561 	}
562 	if (*++q == ':') {
563 		if (*p == '\0' && (p = *argptr++) == NULL)
564 			error("No arg for -%c option", c);
565 		shoptarg = p;
566 		p = NULL;
567 	}
568 	nextopt_optptr = p;
569 	return c;
570 }
571