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
58 char *arg0; /* value of $0 */
59 struct shparam shellparam; /* current positional parameters */
60 char **argptr; /* argument list for builtin commands */
61 char *shoptarg; /* set by nextopt (like getopt) */
62 char *nextopt_optptr; /* used by nextopt */
63
64 char *minusc; /* argument to -c option */
65
66
67 static int options(int);
68 static void minus_o(char *, int);
69 static void setoption(int, int);
70 static void setoptionbyindex(int, int);
71 static void setparam(int, char **);
72 static int getopts(char *, char *, char **, char ***, char **);
73
74
75 /*
76 * Process the shell command line arguments.
77 */
78
79 int
procargs(int argc,char ** argv)80 procargs(int argc, char **argv)
81 {
82 int i, login;
83 char *scriptname;
84
85 argptr = argv;
86 login = argptr[0] != NULL && argptr[0][0] == '-';
87 if (argc > 0)
88 argptr++;
89 for (i = 0; i < NOPTS; i++)
90 optval[i] = 2;
91 privileged = (getuid() != geteuid() || getgid() != getegid());
92 login |= 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 for (i = 0; i < NOPTS; i++)
103 if (optval[i] == 2)
104 optval[i] = 0;
105 arg0 = argv[0];
106 if (sflag == 0 && minusc == NULL) {
107 scriptname = *argptr++;
108 setinputfile(scriptname, 0, -1 /* verify */);
109 commandname = arg0 = scriptname;
110 }
111 /* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
112 if (argptr && minusc && *argptr)
113 arg0 = *argptr++;
114
115 shellparam.p = argptr;
116 shellparam.reset = 1;
117 /* assert(shellparam.malloc == 0 && shellparam.nparam == 0); */
118 while (*argptr) {
119 shellparam.nparam++;
120 argptr++;
121 }
122 optschanged();
123
124 return (login);
125 }
126
127
128 void
optschanged(void)129 optschanged(void)
130 {
131 setinteractive();
132 #ifndef NO_HISTORY
133 histedit();
134 #endif
135 setjobctl(mflag);
136 }
137
138 /*
139 * Process shell options. The global variable argptr contains a pointer
140 * to the argument list; we advance it past the options.
141 * If cmdline is true, process the shell's argv; otherwise, process arguments
142 * to the set special builtin.
143 */
144
145 static int
options(int cmdline)146 options(int cmdline)
147 {
148 char *kp, *p;
149 int val;
150 int c;
151 int login = 0;
152
153 if (cmdline)
154 minusc = NULL;
155 while ((p = *argptr) != NULL) {
156 argptr++;
157 if ((c = *p++) == '-') {
158 val = 1;
159 /* A "-" or "--" terminates options */
160 if (p[0] == '\0')
161 goto end_options1;
162 if (p[0] == '-' && p[1] == '\0')
163 goto end_options2;
164 /**
165 * For the benefit of `#!' lines in shell scripts,
166 * treat a string of '-- *#.*' the same as '--'.
167 * This is needed so that a script starting with:
168 * #!/bin/sh -- # -*- perl -*-
169 * will continue to work after a change is made to
170 * kern/imgact_shell.c to NOT token-ize the options
171 * specified on a '#!' line. A bit of a kludge,
172 * but that trick is recommended in documentation
173 * for some scripting languages, and we might as
174 * well continue to support it.
175 */
176 if (p[0] == '-') {
177 kp = p + 1;
178 while (*kp == ' ' || *kp == '\t')
179 kp++;
180 if (*kp == '#' || *kp == '\0')
181 goto end_options2;
182 }
183 } else if (c == '+') {
184 val = 0;
185 } else {
186 argptr--;
187 break;
188 }
189 while ((c = *p++) != '\0') {
190 if (c == 'c' && cmdline) {
191 char *q;
192
193 q = *argptr++;
194 if (q == NULL || minusc != NULL)
195 error("Bad -c option");
196 minusc = q;
197 } else if (c == 'l' && cmdline) {
198 login = 1;
199 } else if (c == 'o') {
200 minus_o(*argptr, val);
201 if (*argptr)
202 argptr++;
203 } else
204 setoption(c, val);
205 }
206 }
207 return (login);
208
209 /* When processing `set', a single "-" means turn off -x and -v */
210 end_options1:
211 if (!cmdline) {
212 xflag = vflag = 0;
213 return (login);
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 */
222 end_options2:
223 if (!cmdline) {
224 if (*argptr == NULL)
225 setparam(0, argptr);
226 return (login);
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 return (login);
247 }
248
249 static void
minus_o(char * name,int val)250 minus_o(char *name, int val)
251 {
252 int i;
253 const unsigned char *on;
254 size_t len;
255
256 if (name == NULL) {
257 if (val) {
258 /* "Pretty" output. */
259 out1str("Current option settings\n");
260 for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
261 out1fmt("%-16.*s%s\n", *on, on + 1,
262 optval[i] ? "on" : "off");
263 } else {
264 /* Output suitable for re-input to shell. */
265 for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
266 out1fmt("%s %co %.*s%s",
267 i % 6 == 0 ? "set" : "",
268 optval[i] ? '-' : '+',
269 *on, on + 1,
270 i % 6 == 5 || i == NOPTS - 1 ? "\n" : "");
271 }
272 } else {
273 len = strlen(name);
274 for (i = 0, on = optname; i < NOPTS; i++, on += *on + 1)
275 if (*on == len && memcmp(on + 1, name, len) == 0) {
276 setoptionbyindex(i, val);
277 return;
278 }
279 error("Illegal option -o %s", name);
280 }
281 }
282
283
284 static void
setoptionbyindex(int idx,int val)285 setoptionbyindex(int idx, int val)
286 {
287 if (&optval[idx] == &privileged && !val && privileged) {
288 if (setgid(getgid()) == -1)
289 error("setgid");
290 if (setuid(getuid()) == -1)
291 error("setuid");
292 }
293 optval[idx] = val;
294 if (val) {
295 /* #%$ hack for ksh semantics */
296 if (&optval[idx] == &Vflag)
297 Eflag = 0;
298 else if (&optval[idx] == &Eflag)
299 Vflag = 0;
300 }
301 }
302
303 static void
setoption(int flag,int val)304 setoption(int flag, int val)
305 {
306 int i;
307
308 for (i = 0; i < NSHORTOPTS; i++)
309 if (optletter[i] == flag) {
310 setoptionbyindex(i, val);
311 return;
312 }
313 error("Illegal option -%c", flag);
314 }
315
316
317 /*
318 * Set the shell parameters.
319 */
320
321 static void
setparam(int argc,char ** argv)322 setparam(int argc, char **argv)
323 {
324 char **newparam;
325 char **ap;
326
327 ap = newparam = ckmalloc((argc + 1) * sizeof *ap);
328 while (*argv) {
329 *ap++ = savestr(*argv++);
330 }
331 *ap = NULL;
332 freeparam(&shellparam);
333 shellparam.malloc = 1;
334 shellparam.nparam = argc;
335 shellparam.p = newparam;
336 shellparam.optp = NULL;
337 shellparam.reset = 1;
338 shellparam.optnext = NULL;
339 }
340
341
342 /*
343 * Free the list of positional parameters.
344 */
345
346 void
freeparam(struct shparam * param)347 freeparam(struct shparam *param)
348 {
349 char **ap;
350
351 if (param->malloc) {
352 for (ap = param->p ; *ap ; ap++)
353 ckfree(*ap);
354 ckfree(param->p);
355 }
356 if (param->optp) {
357 for (ap = param->optp ; *ap ; ap++)
358 ckfree(*ap);
359 ckfree(param->optp);
360 }
361 }
362
363
364
365 /*
366 * The shift builtin command.
367 */
368
369 int
shiftcmd(int argc,char ** argv)370 shiftcmd(int argc, char **argv)
371 {
372 int i, n;
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 if (shellparam.malloc)
382 for (i = 0; i < n; i++)
383 ckfree(shellparam.p[i]);
384 memmove(shellparam.p, shellparam.p + n,
385 (shellparam.nparam + 1) * sizeof(shellparam.p[0]));
386 shellparam.reset = 1;
387 INTON;
388 return 0;
389 }
390
391
392
393 /*
394 * The set builtin command.
395 */
396
397 int
setcmd(int argc,char ** argv)398 setcmd(int argc, char **argv)
399 {
400 if (argc == 1)
401 return showvarscmd(argc, argv);
402 INTOFF;
403 options(0);
404 optschanged();
405 if (*argptr != NULL) {
406 setparam(argc - (argptr - argv), argptr);
407 }
408 INTON;
409 return 0;
410 }
411
412
413 void
getoptsreset(const char * value)414 getoptsreset(const char *value)
415 {
416 while (*value == '0')
417 value++;
418 if (strcmp(value, "1") == 0)
419 shellparam.reset = 1;
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
429 int
getoptscmd(int argc,char ** argv)430 getoptscmd(int argc, char **argv)
431 {
432 char **optbase = NULL, **ap;
433 int i;
434
435 if (argc < 3)
436 error("usage: getopts optstring var [arg]");
437
438 if (shellparam.reset == 1) {
439 INTOFF;
440 if (shellparam.optp) {
441 for (ap = shellparam.optp ; *ap ; ap++)
442 ckfree(*ap);
443 ckfree(shellparam.optp);
444 shellparam.optp = NULL;
445 }
446 if (argc > 3) {
447 shellparam.optp = ckmalloc((argc - 2) * sizeof *ap);
448 memset(shellparam.optp, '\0', (argc - 2) * sizeof *ap);
449 for (i = 0; i < argc - 3; i++)
450 shellparam.optp[i] = savestr(argv[i + 3]);
451 }
452 INTON;
453 optbase = argc == 3 ? shellparam.p : shellparam.optp;
454 shellparam.optnext = optbase;
455 shellparam.optptr = NULL;
456 shellparam.reset = 0;
457 } else
458 optbase = shellparam.optp ? shellparam.optp : shellparam.p;
459
460 return getopts(argv[1], argv[2], optbase, &shellparam.optnext,
461 &shellparam.optptr);
462 }
463
464 static int
getopts(char * optstr,char * optvar,char ** optfirst,char *** optnext,char ** optptr)465 getopts(char *optstr, char *optvar, char **optfirst, char ***optnext,
466 char **optptr)
467 {
468 char *p, *q;
469 char c = '?';
470 int done = 0;
471 int ind = 0;
472 int err = 0;
473 char s[10];
474 const char *newoptarg = NULL;
475
476 if ((p = *optptr) == NULL || *p == '\0') {
477 /* Current word is done, advance */
478 if (*optnext == NULL)
479 return 1;
480 p = **optnext;
481 if (p == NULL || *p != '-' || *++p == '\0') {
482 atend:
483 ind = *optnext - optfirst + 1;
484 *optnext = NULL;
485 p = NULL;
486 done = 1;
487 goto out;
488 }
489 (*optnext)++;
490 if (p[0] == '-' && p[1] == '\0') /* check for "--" */
491 goto atend;
492 }
493
494 c = *p++;
495 for (q = optstr; *q != c; ) {
496 if (*q == '\0') {
497 if (optstr[0] == ':') {
498 s[0] = c;
499 s[1] = '\0';
500 newoptarg = s;
501 }
502 else
503 out2fmt_flush("Illegal option -%c\n", c);
504 c = '?';
505 goto out;
506 }
507 if (*++q == ':')
508 q++;
509 }
510
511 if (*++q == ':') {
512 if (*p == '\0' && (p = **optnext) == NULL) {
513 if (optstr[0] == ':') {
514 s[0] = c;
515 s[1] = '\0';
516 newoptarg = s;
517 c = ':';
518 }
519 else {
520 out2fmt_flush("No arg for -%c option\n", c);
521 c = '?';
522 }
523 goto out;
524 }
525
526 if (p == **optnext)
527 (*optnext)++;
528 newoptarg = p;
529 p = NULL;
530 }
531
532 out:
533 if (*optnext != NULL)
534 ind = *optnext - optfirst + 1;
535 *optptr = p;
536 if (newoptarg != NULL)
537 err |= setvarsafe("OPTARG", newoptarg, 0);
538 else {
539 INTOFF;
540 err |= unsetvar("OPTARG");
541 INTON;
542 }
543 fmtstr(s, sizeof(s), "%d", ind);
544 err |= setvarsafe("OPTIND", s, VNOFUNC);
545 s[0] = c;
546 s[1] = '\0';
547 err |= setvarsafe(optvar, s, 0);
548 if (err) {
549 *optnext = NULL;
550 *optptr = NULL;
551 flushall();
552 exraise(EXERROR);
553 }
554 return done;
555 }
556
557 /*
558 * Standard option processing (a la getopt) for builtin routines. The
559 * only argument that is passed to nextopt is the option string; the
560 * other arguments are unnecessary. It returns the option, or '\0' on
561 * end of input.
562 */
563
564 int
nextopt(const char * optstring)565 nextopt(const char *optstring)
566 {
567 char *p;
568 const char *q;
569 char c;
570
571 if ((p = nextopt_optptr) == NULL || *p == '\0') {
572 p = *argptr;
573 if (p == NULL || *p != '-' || *++p == '\0')
574 return '\0';
575 argptr++;
576 if (p[0] == '-' && p[1] == '\0') /* check for "--" */
577 return '\0';
578 }
579 c = *p++;
580 for (q = optstring ; *q != c ; ) {
581 if (*q == '\0')
582 error("Illegal option -%c", c);
583 if (*++q == ':')
584 q++;
585 }
586 if (*++q == ':') {
587 if (*p == '\0' && (p = *argptr++) == NULL)
588 error("No arg for -%c option", c);
589 shoptarg = p;
590 p = NULL;
591 }
592 if (p != NULL && *p != '\0')
593 nextopt_optptr = p;
594 else
595 nextopt_optptr = NULL;
596 return c;
597 }
598