1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <signal.h>
36#include <unistd.h>
37#include <stdlib.h>
38
39#include "shell.h"
40#define DEFINE_OPTIONS
41#include "options.h"
42#undef DEFINE_OPTIONS
43#include "nodes.h"	/* for other header files */
44#include "eval.h"
45#include "jobs.h"
46#include "input.h"
47#include "output.h"
48#include "trap.h"
49#include "var.h"
50#include "memalloc.h"
51#include "error.h"
52#include "mystring.h"
53#include "builtins.h"
54#ifndef NO_HISTORY
55#include "myhistedit.h"
56#endif
57
58char *arg0;			/* value of $0 */
59struct shparam shellparam;	/* current positional parameters */
60char **argptr;			/* argument list for builtin commands */
61char *shoptarg;			/* set by nextopt (like getopt) */
62char *nextopt_optptr;		/* used by nextopt */
63
64char *minusc;			/* argument to -c option */
65
66
67static void options(int);
68static void minus_o(char *, int);
69static void setoption(int, int);
70static void setoptionbyindex(int, int);
71static void setparam(int, char **);
72static int getopts(char *, char *, char **, char ***, char **);
73
74
75/*
76 * Process the shell command line arguments.
77 */
78
79void
80procargs(int argc, char **argv)
81{
82	int i;
83	char *scriptname;
84
85	argptr = argv;
86	if (argc > 0)
87		argptr++;
88	for (i = 0; i < NOPTS; i++)
89		optval[i] = 2;
90	privileged = (getuid() != geteuid() || getgid() != getegid());
91	options(1);
92	if (*argptr == NULL && minusc == NULL)
93		sflag = 1;
94	if (iflag != 0 && sflag == 1 && isatty(0) && isatty(1)) {
95		iflag = 1;
96		if (Eflag == 2)
97			Eflag = 1;
98	}
99	if (mflag == 2)
100		mflag = iflag;
101	for (i = 0; i < NOPTS; i++)
102		if (optval[i] == 2)
103			optval[i] = 0;
104	arg0 = argv[0];
105	if (sflag == 0 && minusc == NULL) {
106		scriptname = *argptr++;
107		setinputfile(scriptname, 0, -1 /* verify */);
108		commandname = arg0 = scriptname;
109	}
110	/* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
111	if (argptr && minusc && *argptr)
112		arg0 = *argptr++;
113
114	shellparam.p = argptr;
115	shellparam.reset = 1;
116	/* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
117	while (*argptr) {
118		shellparam.nparam++;
119		argptr++;
120	}
121	optschanged();
122}
123
124
125void
126optschanged(void)
127{
128	setinteractive();
129#ifndef NO_HISTORY
130	histedit();
131#endif
132	setjobctl(mflag);
133}
134
135/*
136 * Process shell options.  The global variable argptr contains a pointer
137 * to the argument list; we advance it past the options.
138 * If cmdline is true, process the shell's argv; otherwise, process arguments
139 * to the set special builtin.
140 */
141
142static void
143options(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
189				q = *argptr++;
190				if (q == NULL || minusc != NULL)
191					error("Bad -c option");
192				minusc = q;
193			} else if (c == 'o') {
194				minus_o(*argptr, val);
195				if (*argptr)
196					argptr++;
197			} else
198				setoption(c, val);
199		}
200	}
201	return;
202
203	/* When processing `set', a single "-" means turn off -x and -v */
204end_options1:
205	if (!cmdline) {
206		xflag = vflag = 0;
207		return;
208	}
209
210	/*
211	 * When processing `set', a "--" means the remaining arguments
212	 * replace the positional parameters in the active shell.  If
213	 * there are no remaining options, then all the positional
214	 * parameters are cleared (equivalent to doing ``shift $#'').
215	 */
216end_options2:
217	if (!cmdline) {
218		if (*argptr == NULL)
219			setparam(0, argptr);
220		return;
221	}
222
223	/*
224	 * At this point we are processing options given to 'sh' on a command
225	 * line.  If an end-of-options marker ("-" or "--") is followed by an
226	 * arg of "#", then skip over all remaining arguments.  Some scripting
227	 * languages (e.g.: perl) document that /bin/sh will implement this
228	 * behavior, and they recommend that users take advantage of it to
229	 * solve certain issues that can come up when writing a perl script.
230	 * Yes, this feature is in /bin/sh to help users write perl scripts.
231	 */
232	p = *argptr;
233	if (p != NULL && p[0] == '#' && p[1] == '\0') {
234		while (*argptr != NULL)
235			argptr++;
236		/* We need to keep the final argument */
237		argptr--;
238	}
239}
240
241static void
242minus_o(char *name, int val)
243{
244	int i;
245	const unsigned char *on;
246	size_t len;
247
248	if (name == NULL) {
249		if (val) {
250			/* "Pretty" output. */
251			out1str("Current option settings\n");
252			for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
253				out1fmt("%-16.*s%s\n", *on, on + 1,
254					optval[i] ? "on" : "off");
255		} else {
256			/* Output suitable for re-input to shell. */
257			for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
258				out1fmt("%s %co %.*s%s",
259				    i % 6 == 0 ? "set" : "",
260				    optval[i] ? '-' : '+',
261				    *on, on + 1,
262				    i % 6 == 5 || i == NOPTS - 1 ? "\n" : "");
263		}
264	} else {
265		len = strlen(name);
266		for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
267			if (*on == len && memcmp(on + 1, name, len) == 0) {
268				setoptionbyindex(i, val);
269				return;
270			}
271		error("Illegal option -o %s", name);
272	}
273}
274
275
276static void
277setoptionbyindex(int idx, int val)
278{
279	if (&optval[idx] == &privileged && !val && privileged) {
280		if (setgid(getgid()) == -1)
281			error("setgid");
282		if (setuid(getuid()) == -1)
283			error("setuid");
284	}
285	optval[idx] = val;
286	if (val) {
287		/* #%$ hack for ksh semantics */
288		if (&optval[idx] == &Vflag)
289			Eflag = 0;
290		else if (&optval[idx] == &Eflag)
291			Vflag = 0;
292	}
293}
294
295static void
296setoption(int flag, int val)
297{
298	int i;
299
300	for (i = 0; i < NSHORTOPTS; i++)
301		if (optletter[i] == flag) {
302			setoptionbyindex(i, val);
303			return;
304		}
305	error("Illegal option -%c", flag);
306}
307
308
309/*
310 * Set the shell parameters.
311 */
312
313static void
314setparam(int argc, char **argv)
315{
316	char **newparam;
317	char **ap;
318
319	ap = newparam = ckmalloc((argc + 1) * sizeof *ap);
320	while (*argv) {
321		*ap++ = savestr(*argv++);
322	}
323	*ap = NULL;
324	freeparam(&shellparam);
325	shellparam.malloc = 1;
326	shellparam.nparam = argc;
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
338void
339freeparam(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
361int
362shiftcmd(int argc, char **argv)
363{
364	int i, n;
365
366	n = 1;
367	if (argc > 1)
368		n = number(argv[1]);
369	if (n > shellparam.nparam)
370		return 1;
371	INTOFF;
372	shellparam.nparam -= n;
373	if (shellparam.malloc)
374		for (i = 0; i < n; i++)
375			ckfree(shellparam.p[i]);
376	memmove(shellparam.p, shellparam.p + n,
377	    (shellparam.nparam + 1) * sizeof(shellparam.p[0]));
378	shellparam.reset = 1;
379	INTON;
380	return 0;
381}
382
383
384
385/*
386 * The set builtin command.
387 */
388
389int
390setcmd(int argc, char **argv)
391{
392	if (argc == 1)
393		return showvarscmd(argc, argv);
394	INTOFF;
395	options(0);
396	optschanged();
397	if (*argptr != NULL) {
398		setparam(argc - (argptr - argv), argptr);
399	}
400	INTON;
401	return 0;
402}
403
404
405void
406getoptsreset(const char *value)
407{
408	while (*value == '0')
409		value++;
410	if (strcmp(value, "1") == 0)
411		shellparam.reset = 1;
412}
413
414/*
415 * The getopts builtin.  Shellparam.optnext points to the next argument
416 * to be processed.  Shellparam.optptr points to the next character to
417 * be processed in the current argument.  If shellparam.optnext is NULL,
418 * then it's the first time getopts has been called.
419 */
420
421int
422getoptscmd(int argc, char **argv)
423{
424	char **optbase = NULL, **ap;
425	int i;
426
427	if (argc < 3)
428		error("usage: getopts optstring var [arg]");
429
430	if (shellparam.reset == 1) {
431		INTOFF;
432		if (shellparam.optp) {
433			for (ap = shellparam.optp ; *ap ; ap++)
434				ckfree(*ap);
435			ckfree(shellparam.optp);
436			shellparam.optp = NULL;
437		}
438		if (argc > 3) {
439			shellparam.optp = ckmalloc((argc - 2) * sizeof *ap);
440			memset(shellparam.optp, '\0', (argc - 2) * sizeof *ap);
441			for (i = 0; i < argc - 3; i++)
442				shellparam.optp[i] = savestr(argv[i + 3]);
443		}
444		INTON;
445		optbase = argc == 3 ? shellparam.p : shellparam.optp;
446		shellparam.optnext = optbase;
447		shellparam.optptr = NULL;
448		shellparam.reset = 0;
449	} else
450		optbase = shellparam.optp ? shellparam.optp : shellparam.p;
451
452	return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
453		       &shellparam.optptr);
454}
455
456static int
457getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
458    char **optptr)
459{
460	char *p, *q;
461	char c = '?';
462	int done = 0;
463	int ind = 0;
464	int err = 0;
465	char s[10];
466	const char *newoptarg = NULL;
467
468	if ((p = *optptr) == NULL || *p == '\0') {
469		/* Current word is done, advance */
470		if (*optnext == NULL)
471			return 1;
472		p = **optnext;
473		if (p == NULL || *p != '-' || *++p == '\0') {
474atend:
475			ind = *optnext - optfirst + 1;
476			*optnext = NULL;
477			p = NULL;
478			done = 1;
479			goto out;
480		}
481		(*optnext)++;
482		if (p[0] == '-' && p[1] == '\0')	/* check for "--" */
483			goto atend;
484	}
485
486	c = *p++;
487	for (q = optstr; *q != c; ) {
488		if (*q == '\0') {
489			if (optstr[0] == ':') {
490				s[0] = c;
491				s[1] = '\0';
492				newoptarg = s;
493			}
494			else
495				out2fmt_flush("Illegal option -%c\n", c);
496			c = '?';
497			goto out;
498		}
499		if (*++q == ':')
500			q++;
501	}
502
503	if (*++q == ':') {
504		if (*p == '\0' && (p = **optnext) == NULL) {
505			if (optstr[0] == ':') {
506				s[0] = c;
507				s[1] = '\0';
508				newoptarg = s;
509				c = ':';
510			}
511			else {
512				out2fmt_flush("No arg for -%c option\n", c);
513				c = '?';
514			}
515			goto out;
516		}
517
518		if (p == **optnext)
519			(*optnext)++;
520		newoptarg = p;
521		p = NULL;
522	}
523
524out:
525	if (*optnext != NULL)
526		ind = *optnext - optfirst + 1;
527	*optptr = p;
528	if (newoptarg != NULL)
529		err |= setvarsafe("OPTARG", newoptarg, 0);
530	else {
531		INTOFF;
532		err |= unsetvar("OPTARG");
533		INTON;
534	}
535	fmtstr(s, sizeof(s), "%d", ind);
536	err |= setvarsafe("OPTIND", s, VNOFUNC);
537	s[0] = c;
538	s[1] = '\0';
539	err |= setvarsafe(optvar, s, 0);
540	if (err) {
541		*optnext = NULL;
542		*optptr = NULL;
543		flushall();
544		exraise(EXERROR);
545	}
546	return done;
547}
548
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 returns the option, 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 = nextopt_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	if (p != NULL && *p != '\0')
585		nextopt_optptr = p;
586	else
587		nextopt_optptr = NULL;
588	return c;
589}
590