options.c revision 200956 
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
35static char sccsid[] = "@(#)options.c	8.2 (Berkeley) 5/4/95";
36#endif
37#endif /* not lint */
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: head/bin/sh/options.c 200956 2009-12-24 18:41:14Z jilles $");
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#ifndef NO_HISTORY
60#include "myhistedit.h"
61#endif
62
63char *arg0;			/* value of $0 */
64struct shparam shellparam;	/* current positional parameters */
65char **argptr;			/* argument list for builtin commands */
66char *shoptarg;			/* set by nextopt (like getopt) */
67char *optptr;			/* used by nextopt */
68
69char *minusc;			/* argument to -c option */
70
71
72STATIC void options(int);
73STATIC void minus_o(char *, int);
74STATIC void setoption(int, int);
75STATIC int getopts(char *, char *, char **, char ***, char **);
76
77
78/*
79 * Process the shell command line arguments.
80 */
81
82void
83procargs(int argc, char **argv)
84{
85	int i;
86
87	argptr = argv;
88	if (argc > 0)
89		argptr++;
90	for (i = 0; i < NOPTS; i++)
91		optlist[i].val = 2;
92	privileged = (getuid() != geteuid() || getgid() != getegid());
93	options(1);
94	if (*argptr == NULL && minusc == NULL)
95		sflag = 1;
96	if (iflag == 2 && sflag == 1 && isatty(0) && isatty(1))
97		iflag = 1;
98	if (mflag == 2)
99		mflag = iflag;
100	for (i = 0; i < NOPTS; i++)
101		if (optlist[i].val == 2)
102			optlist[i].val = 0;
103	arg0 = argv[0];
104	if (sflag == 0 && minusc == NULL) {
105		commandname = arg0 = *argptr++;
106		setinputfile(commandname, 0);
107	}
108	/* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
109	if (argptr && minusc && *argptr)
110		arg0 = *argptr++;
111
112	shellparam.p = argptr;
113	shellparam.reset = 1;
114	/* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
115	while (*argptr) {
116		shellparam.nparam++;
117		argptr++;
118	}
119	optschanged();
120}
121
122
123void
124optschanged(void)
125{
126	setinteractive(iflag);
127#ifndef NO_HISTORY
128	histedit();
129#endif
130	setjobctl(mflag);
131}
132
133/*
134 * Process shell options.  The global variable argptr contains a pointer
135 * to the argument list; we advance it past the options.
136 */
137
138STATIC void
139options(int cmdline)
140{
141	char *kp, *p;
142	int val;
143	int c;
144
145	if (cmdline)
146		minusc = NULL;
147	while ((p = *argptr) != NULL) {
148		argptr++;
149		if ((c = *p++) == '-') {
150			val = 1;
151			/* A "-" or  "--" terminates options */
152			if (p[0] == '\0')
153				goto end_options1;
154			if (p[0] == '-' && p[1] == '\0')
155				goto end_options2;
156			/**
157			 * For the benefit of `#!' lines in shell scripts,
158			 * treat a string of '-- *#.*' the same as '--'.
159			 * This is needed so that a script starting with:
160			 *	#!/bin/sh -- # -*- perl -*-
161			 * will continue to work after a change is made to
162			 * kern/imgact_shell.c to NOT token-ize the options
163			 * specified on a '#!' line.  A bit of a kludge,
164			 * but that trick is recommended in documentation
165			 * for some scripting languages, and we might as
166			 * well continue to support it.
167			 */
168			if (p[0] == '-') {
169				kp = p + 1;
170				while (*kp == ' ' || *kp == '\t')
171					kp++;
172				if (*kp == '#' || *kp == '\0')
173					goto end_options2;
174			}
175		} else if (c == '+') {
176			val = 0;
177		} else {
178			argptr--;
179			break;
180		}
181		while ((c = *p++) != '\0') {
182			if (c == 'c' && cmdline) {
183				char *q;
184#ifdef NOHACK	/* removing this code allows sh -ce 'foo' for compat */
185				if (*p == '\0')
186#endif
187					q = *argptr++;
188				if (q == NULL || minusc != NULL)
189					error("Bad -c option");
190				minusc = q;
191#ifdef NOHACK
192				break;
193#endif
194			} else if (c == 'o') {
195				minus_o(*argptr, val);
196				if (*argptr)
197					argptr++;
198			} else {
199				if (c == 'p' && !val && privileged) {
200					(void) setuid(getuid());
201					(void) setgid(getgid());
202				}
203				setoption(c, val);
204			}
205		}
206	}
207	return;
208
209	/* When processing `set', a single "-" means turn off -x and -v */
210end_options1:
211	if (!cmdline) {
212		xflag = vflag = 0;
213		return;
214	}
215
216	/*
217	 * When processing `set', a "--" means the remaining arguments
218	 * replace the positional parameters in the active shell.  If
219	 * there are no remaining options, then all the positional
220	 * parameters are cleared (equivalent to doing ``shift $#'').
221	 */
222end_options2:
223	if (!cmdline) {
224		if (*argptr == NULL)
225			setparam(argptr);
226		return;
227	}
228
229	/*
230	 * At this point we are processing options given to 'sh' on a command
231	 * line.  If an end-of-options marker ("-" or "--") is followed by an
232	 * arg of "#", then skip over all remaining arguments.  Some scripting
233	 * languages (e.g.: perl) document that /bin/sh will implement this
234	 * behavior, and they recommend that users take advantage of it to
235	 * solve certain issues that can come up when writing a perl script.
236	 * Yes, this feature is in /bin/sh to help users write perl scripts.
237	 */
238	p = *argptr;
239	if (p != NULL && p[0] == '#' && p[1] == '\0') {
240		while (*argptr != NULL)
241			argptr++;
242		/* We need to keep the final argument */
243		argptr--;
244	}
245}
246
247STATIC void
248minus_o(char *name, int val)
249{
250	int i;
251
252	if (name == NULL) {
253		if (val) {
254			/* "Pretty" output. */
255			out1str("Current option settings\n");
256			for (i = 0; i < NOPTS; i++)
257				out1fmt("%-16s%s\n", optlist[i].name,
258					optlist[i].val ? "on" : "off");
259		} else {
260			/* Output suitable for re-input to shell. */
261			for (i = 0; i < NOPTS; i++) {
262				if (i % 6 == 0)
263					out1str(i == 0 ? "set" : "\nset");
264				out1fmt(" %co %s", optlist[i].val ? '-' : '+',
265					optlist[i].name);
266			}
267			out1c('\n');
268		}
269	} else {
270		for (i = 0; i < NOPTS; i++)
271			if (equal(name, optlist[i].name)) {
272				if (!val && privileged && equal(name, "privileged")) {
273					(void) setuid(getuid());
274					(void) setgid(getgid());
275				}
276				setoption(optlist[i].letter, val);
277				return;
278			}
279		error("Illegal option -o %s", name);
280	}
281}
282
283
284STATIC void
285setoption(int flag, int val)
286{
287	int i;
288
289	for (i = 0; i < NOPTS; i++)
290		if (optlist[i].letter == flag) {
291			optlist[i].val = val;
292			if (val) {
293				/* #%$ hack for ksh semantics */
294				if (flag == 'V')
295					Eflag = 0;
296				else if (flag == 'E')
297					Vflag = 0;
298			}
299			return;
300		}
301	error("Illegal option -%c", flag);
302}
303
304
305
306#ifdef mkinit
307INCLUDE "options.h"
308
309SHELLPROC {
310	int i;
311
312	for (i = 0; i < NOPTS; i++)
313		optlist[i].val = 0;
314	optschanged();
315
316}
317#endif
318
319
320/*
321 * Set the shell parameters.
322 */
323
324void
325setparam(char **argv)
326{
327	char **newparam;
328	char **ap;
329	int nparam;
330
331	for (nparam = 0 ; argv[nparam] ; nparam++);
332	ap = newparam = ckmalloc((nparam + 1) * sizeof *ap);
333	while (*argv) {
334		*ap++ = savestr(*argv++);
335	}
336	*ap = NULL;
337	freeparam(&shellparam);
338	shellparam.malloc = 1;
339	shellparam.nparam = nparam;
340	shellparam.p = newparam;
341	shellparam.reset = 1;
342	shellparam.optnext = NULL;
343}
344
345
346/*
347 * Free the list of positional parameters.
348 */
349
350void
351freeparam(struct shparam *param)
352{
353	char **ap;
354
355	if (param->malloc) {
356		for (ap = param->p ; *ap ; ap++)
357			ckfree(*ap);
358		ckfree(param->p);
359	}
360}
361
362
363
364/*
365 * The shift builtin command.
366 */
367
368int
369shiftcmd(int argc, char **argv)
370{
371	int n;
372	char **ap1, **ap2;
373
374	n = 1;
375	if (argc > 1)
376		n = number(argv[1]);
377	if (n > shellparam.nparam)
378		return 1;
379	INTOFF;
380	shellparam.nparam -= n;
381	for (ap1 = shellparam.p ; --n >= 0 ; ap1++) {
382		if (shellparam.malloc)
383			ckfree(*ap1);
384	}
385	ap2 = shellparam.p;
386	while ((*ap2++ = *ap1++) != NULL);
387	shellparam.reset = 1;
388	INTON;
389	return 0;
390}
391
392
393
394/*
395 * The set command builtin.
396 */
397
398int
399setcmd(int argc, char **argv)
400{
401	if (argc == 1)
402		return showvarscmd(argc, argv);
403	INTOFF;
404	options(0);
405	optschanged();
406	if (*argptr != NULL) {
407		setparam(argptr);
408	}
409	INTON;
410	return 0;
411}
412
413
414void
415getoptsreset(const char *value)
416{
417	if (number(value) == 1) {
418		shellparam.reset = 1;
419	}
420}
421
422/*
423 * The getopts builtin.  Shellparam.optnext points to the next argument
424 * to be processed.  Shellparam.optptr points to the next character to
425 * be processed in the current argument.  If shellparam.optnext is NULL,
426 * then it's the first time getopts has been called.
427 */
428
429int
430getoptscmd(int argc, char **argv)
431{
432	char **optbase = NULL;
433
434	if (argc < 3)
435		error("usage: getopts optstring var [arg]");
436	else if (argc == 3)
437		optbase = shellparam.p;
438	else
439		optbase = &argv[3];
440
441	if (shellparam.reset == 1) {
442		shellparam.optnext = optbase;
443		shellparam.optptr = NULL;
444		shellparam.reset = 0;
445	}
446
447	return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
448		       &shellparam.optptr);
449}
450
451STATIC int
452getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
453    char **optptr)
454{
455	char *p, *q;
456	char c = '?';
457	int done = 0;
458	int ind = 0;
459	int err = 0;
460	char s[10];
461
462	if ((p = *optptr) == NULL || *p == '\0') {
463		/* Current word is done, advance */
464		if (*optnext == NULL)
465			return 1;
466		p = **optnext;
467		if (p == NULL || *p != '-' || *++p == '\0') {
468atend:
469			ind = *optnext - optfirst + 1;
470			*optnext = NULL;
471			p = NULL;
472			done = 1;
473			goto out;
474		}
475		(*optnext)++;
476		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
477			goto atend;
478	}
479
480	c = *p++;
481	for (q = optstr; *q != c; ) {
482		if (*q == '\0') {
483			if (optstr[0] == ':') {
484				s[0] = c;
485				s[1] = '\0';
486				err |= setvarsafe("OPTARG", s, 0);
487			}
488			else {
489				out1fmt("Illegal option -%c\n", c);
490				(void) unsetvar("OPTARG");
491			}
492			c = '?';
493			goto bad;
494		}
495		if (*++q == ':')
496			q++;
497	}
498
499	if (*++q == ':') {
500		if (*p == '\0' && (p = **optnext) == NULL) {
501			if (optstr[0] == ':') {
502				s[0] = c;
503				s[1] = '\0';
504				err |= setvarsafe("OPTARG", s, 0);
505				c = ':';
506			}
507			else {
508				out1fmt("No arg for -%c option\n", c);
509				(void) unsetvar("OPTARG");
510				c = '?';
511			}
512			goto bad;
513		}
514
515		if (p == **optnext)
516			(*optnext)++;
517		setvarsafe("OPTARG", p, 0);
518		p = NULL;
519	}
520	else
521		setvarsafe("OPTARG", "", 0);
522	ind = *optnext - optfirst + 1;
523	goto out;
524
525bad:
526	ind = 1;
527	*optnext = NULL;
528	p = NULL;
529out:
530	*optptr = p;
531	fmtstr(s, sizeof(s), "%d", ind);
532	err |= setvarsafe("OPTIND", s, VNOFUNC);
533	s[0] = c;
534	s[1] = '\0';
535	err |= setvarsafe(optvar, s, 0);
536	if (err) {
537		*optnext = NULL;
538		*optptr = NULL;
539		flushall();
540		exraise(EXERROR);
541	}
542	return done;
543}
544
545/*
546 * XXX - should get rid of.  have all builtins use getopt(3).  the
547 * library getopt must have the BSD extension static variable "optreset"
548 * otherwise it can't be used within the shell safely.
549 *
550 * Standard option processing (a la getopt) for builtin routines.  The
551 * only argument that is passed to nextopt is the option string; the
552 * other arguments are unnecessary.  It return the character, or '\0' on
553 * end of input.
554 */
555
556int
557nextopt(const char *optstring)
558{
559	char *p;
560	const char *q;
561	char c;
562
563	if ((p = optptr) == NULL || *p == '\0') {
564		p = *argptr;
565		if (p == NULL || *p != '-' || *++p == '\0')
566			return '\0';
567		argptr++;
568		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
569			return '\0';
570	}
571	c = *p++;
572	for (q = optstring ; *q != c ; ) {
573		if (*q == '\0')
574			error("Illegal option -%c", c);
575		if (*++q == ':')
576			q++;
577	}
578	if (*++q == ':') {
579		if (*p == '\0' && (p = *argptr++) == NULL)
580			error("No arg for -%c option", c);
581		shoptarg = p;
582		p = NULL;
583	}
584	optptr = p;
585	return c;
586}
587