xref: /dragonfly/bin/sh/options.c (revision 10f4bf95)
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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  * @(#)options.c	8.2 (Berkeley) 5/4/95
37  * $FreeBSD: src/bin/sh/options.c,v 1.33 2011/02/04 22:47:55 jilles Exp $
38  */
39 
40 #include <signal.h>
41 #include <unistd.h>
42 #include <stdlib.h>
43 
44 #include "shell.h"
45 #define DEFINE_OPTIONS
46 #include "options.h"
47 #undef DEFINE_OPTIONS
48 #include "nodes.h"	/* for other header files */
49 #include "eval.h"
50 #include "jobs.h"
51 #include "input.h"
52 #include "output.h"
53 #include "trap.h"
54 #include "var.h"
55 #include "memalloc.h"
56 #include "error.h"
57 #include "mystring.h"
58 #ifndef NO_HISTORY
59 #include "myhistedit.h"
60 #endif
61 
62 char *arg0;			/* value of $0 */
63 struct shparam shellparam;	/* current positional parameters */
64 char **argptr;			/* argument list for builtin commands */
65 const char *shoptarg;		/* set by nextopt (like getopt) */
66 char *nextopt_optptr;		/* used by nextopt */
67 
68 char *minusc;			/* argument to -c option */
69 
70 
71 static void options(int);
72 static void minus_o(char *, int);
73 static void setoption(int, int);
74 static int getopts(char *, char *, char **, char ***, char **);
75 
76 
77 /*
78  * Process the shell command line arguments.
79  */
80 
81 void
82 procargs(int argc, char **argv)
83 {
84 	int i;
85 
86 	argptr = argv;
87 	if (argc > 0)
88 		argptr++;
89 	for (i = 0; i < NOPTS; i++)
90 		optlist[i].val = 2;
91 	privileged = (getuid() != geteuid() || getgid() != getegid());
92 	options(1);
93 	if (*argptr == NULL && minusc == NULL)
94 		sflag = 1;
95 	if (iflag != 0 && sflag == 1 && isatty(0) && isatty(1)) {
96 		iflag = 1;
97 		if (Eflag == 2)
98 			Eflag = 1;
99 	}
100 	if (mflag == 2)
101 		mflag = iflag;
102 	/* turn on tabcomplete in an interactive shell by default */
103 	tabcomplete = iflag;
104 	for (i = 0; i < NOPTS; i++)
105 		if (optlist[i].val == 2)
106 			optlist[i].val = 0;
107 	arg0 = argv[0];
108 	if (sflag == 0 && minusc == NULL) {
109 		commandname = arg0 = *argptr++;
110 		setinputfile(commandname, 0);
111 	}
112 	/* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
113 	if (argptr && minusc && *argptr)
114 		arg0 = *argptr++;
115 
116 	shellparam.p = argptr;
117 	shellparam.reset = 1;
118 	/* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
119 	while (*argptr) {
120 		shellparam.nparam++;
121 		argptr++;
122 	}
123 	optschanged();
124 }
125 
126 
127 void
128 optschanged(void)
129 {
130 	setinteractive(iflag);
131 #ifndef NO_HISTORY
132 	histedit();
133 #endif
134 	setjobctl(mflag);
135 }
136 
137 /*
138  * Process shell options.  The global variable argptr contains a pointer
139  * to the argument list; we advance it past the options.
140  */
141 
142 static void
143 options(int cmdline)
144 {
145 	char *kp, *p;
146 	int val;
147 	int c;
148 
149 	if (cmdline)
150 		minusc = NULL;
151 	while ((p = *argptr) != NULL) {
152 		argptr++;
153 		if ((c = *p++) == '-') {
154 			val = 1;
155 			/* A "-" or  "--" terminates options */
156 			if (p[0] == '\0')
157 				goto end_options1;
158 			if (p[0] == '-' && p[1] == '\0')
159 				goto end_options2;
160 			/**
161 			 * For the benefit of `#!' lines in shell scripts,
162 			 * treat a string of '-- *#.*' the same as '--'.
163 			 * This is needed so that a script starting with:
164 			 *	#!/bin/sh -- # -*- perl -*-
165 			 * will continue to work after a change is made to
166 			 * kern/imgact_shell.c to NOT token-ize the options
167 			 * specified on a '#!' line.  A bit of a kludge,
168 			 * but that trick is recommended in documentation
169 			 * for some scripting languages, and we might as
170 			 * well continue to support it.
171 			 */
172 			if (p[0] == '-') {
173 				kp = p + 1;
174 				while (*kp == ' ' || *kp == '\t')
175 					kp++;
176 				if (*kp == '#' || *kp == '\0')
177 					goto end_options2;
178 			}
179 		} else if (c == '+') {
180 			val = 0;
181 		} else {
182 			argptr--;
183 			break;
184 		}
185 		while ((c = *p++) != '\0') {
186 			if (c == 'c' && cmdline) {
187 				char *q;
188 #ifdef NOHACK	/* removing this code allows sh -ce 'foo' for compat */
189 				if (*p == '\0')
190 #endif
191 					q = *argptr++;
192 				if (q == NULL || minusc != NULL)
193 					error("Bad -c option");
194 				minusc = q;
195 #ifdef NOHACK
196 				break;
197 #endif
198 			} else if (c == 'o') {
199 				minus_o(*argptr, val);
200 				if (*argptr)
201 					argptr++;
202 			} else {
203 				if (c == 'p' && !val && privileged) {
204 					setuid(getuid());
205 					setgid(getgid());
206 				}
207 				setoption(c, val);
208 			}
209 		}
210 	}
211 	return;
212 
213 	/* When processing `set', a single "-" means turn off -x and -v */
214 end_options1:
215 	if (!cmdline) {
216 		xflag = vflag = 0;
217 		return;
218 	}
219 
220 	/*
221 	 * When processing `set', a "--" means the remaining arguments
222 	 * replace the positional parameters in the active shell.  If
223 	 * there are no remaining options, then all the positional
224 	 * parameters are cleared (equivalent to doing ``shift $#'').
225 	 */
226 end_options2:
227 	if (!cmdline) {
228 		if (*argptr == NULL)
229 			setparam(argptr);
230 		return;
231 	}
232 
233 	/*
234 	 * At this point we are processing options given to 'sh' on a command
235 	 * line.  If an end-of-options marker ("-" or "--") is followed by an
236 	 * arg of "#", then skip over all remaining arguments.  Some scripting
237 	 * languages (e.g.: perl) document that /bin/sh will implement this
238 	 * behavior, and they recommend that users take advantage of it to
239 	 * solve certain issues that can come up when writing a perl script.
240 	 * Yes, this feature is in /bin/sh to help users write perl scripts.
241 	 */
242 	p = *argptr;
243 	if (p != NULL && p[0] == '#' && p[1] == '\0') {
244 		while (*argptr != NULL)
245 			argptr++;
246 		/* We need to keep the final argument */
247 		argptr--;
248 	}
249 }
250 
251 static void
252 minus_o(char *name, int val)
253 {
254 	int i;
255 
256 	if (name == NULL) {
257 		if (val) {
258 			/* "Pretty" output. */
259 			out1str("Current option settings\n");
260 			for (i = 0; i < NOPTS; i++)
261 				out1fmt("%-16s%s\n", optlist[i].name,
262 					optlist[i].val ? "on" : "off");
263 		} else {
264 			/* Output suitable for re-input to shell. */
265 			for (i = 0; i < NOPTS; i++)
266 				out1fmt("%s %co %s%s",
267 				    i % 6 == 0 ? "set" : "",
268 				    optlist[i].val ? '-' : '+',
269 				    optlist[i].name,
270 				    i % 6 == 5 || i == NOPTS - 1 ? "\n" : "");
271 		}
272 	} else {
273 		for (i = 0; i < NOPTS; i++)
274 			if (equal(name, optlist[i].name)) {
275 				if (!val && privileged && equal(name, "privileged")) {
276 					setuid(getuid());
277 					setgid(getgid());
278 				}
279 				setoption(optlist[i].letter, val);
280 				return;
281 			}
282 		error("Illegal option -o %s", name);
283 	}
284 }
285 
286 
287 static void
288 setoption(int flag, int val)
289 {
290 	int i;
291 
292 	for (i = 0; i < NOPTS; i++)
293 		if (optlist[i].letter == flag) {
294 			optlist[i].val = val;
295 			if (val) {
296 				/* #%$ hack for ksh semantics */
297 				if (flag == 'V')
298 					Eflag = 0;
299 				else if (flag == 'E')
300 					Vflag = 0;
301 			}
302 			return;
303 		}
304 	error("Illegal option -%c", flag);
305 }
306 
307 
308 /*
309  * Set the shell parameters.
310  */
311 
312 void
313 setparam(char **argv)
314 {
315 	char **newparam;
316 	char **ap;
317 	int nparam;
318 
319 	for (nparam = 0 ; argv[nparam] ; nparam++);
320 	ap = newparam = ckmalloc((nparam + 1) * sizeof *ap);
321 	while (*argv) {
322 		*ap++ = savestr(*argv++);
323 	}
324 	*ap = NULL;
325 	freeparam(&shellparam);
326 	shellparam.malloc = 1;
327 	shellparam.nparam = nparam;
328 	shellparam.p = newparam;
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(volatile 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 }
349 
350 
351 
352 /*
353  * The shift builtin command.
354  */
355 
356 int
357 shiftcmd(int argc, char **argv)
358 {
359 	int n;
360 	char **ap1, **ap2;
361 
362 	n = 1;
363 	if (argc > 1)
364 		n = number(argv[1]);
365 	if (n > shellparam.nparam)
366 		return 1;
367 	INTOFF;
368 	shellparam.nparam -= n;
369 	for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
370 		if (shellparam.malloc)
371 			ckfree(*ap1);
372 	}
373 	ap2 = shellparam.p;
374 	while ((*ap2++ = *ap1++) != NULL);
375 	shellparam.reset = 1;
376 	INTON;
377 	return 0;
378 }
379 
380 
381 
382 /*
383  * The set command builtin.
384  */
385 
386 int
387 setcmd(int argc, char **argv)
388 {
389 	if (argc == 1)
390 		return showvarscmd(argc, argv);
391 	INTOFF;
392 	options(0);
393 	optschanged();
394 	if (*argptr != NULL) {
395 		setparam(argptr);
396 	}
397 	INTON;
398 	return 0;
399 }
400 
401 
402 void
403 getoptsreset(const char *value)
404 {
405 	if (number(value) == 1) {
406 		shellparam.reset = 1;
407 	}
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 **optp)
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 = *optp) == 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 				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 				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 	*optp = 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 		*optp = NULL;
527 		flushall();
528 		exraise(EXERROR);
529 	}
530 	return done;
531 }
532 
533 /*
534  * XXX - should get rid of.  have all builtins use getopt(3).  the
535  * library getopt must have the BSD extension static variable "optreset"
536  * otherwise it can't be used within the shell safely.
537  *
538  * Standard option processing (a la getopt) for builtin routines.  The
539  * only argument that is passed to nextopt is the option string; the
540  * other arguments are unnecessary.  It return the character, or '\0' on
541  * end of input.
542  */
543 
544 int
545 nextopt(const char *optstring)
546 {
547 	char *p;
548 	const char *q;
549 	char c;
550 
551 	if ((p = nextopt_optptr) == NULL || *p == '\0') {
552 		p = *argptr;
553 		if (p == NULL || *p != '-' || *++p == '\0')
554 			return '\0';
555 		argptr++;
556 		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
557 			return '\0';
558 	}
559 	c = *p++;
560 	for (q = optstring ; *q != c ; ) {
561 		if (*q == '\0')
562 			error("Illegal option -%c", c);
563 		if (*++q == ':')
564 			q++;
565 	}
566 	if (*++q == ':') {
567 		if (*p == '\0' && (p = *argptr++) == NULL)
568 			error("No arg for -%c option", c);
569 		shoptarg = p;
570 		p = NULL;
571 	}
572 	nextopt_optptr = p;
573 	return c;
574 }
575