1 /* $OpenBSD: misc.c,v 1.38 2013/11/28 10:33:37 sobrado Exp $ */
2 /* $OpenBSD: path.c,v 1.12 2005/03/30 17:16:37 deraadt Exp $ */
3
4 /*-
5 * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
6 * 2011, 2012, 2013, 2014
7 * Thorsten Glaser <tg@mirbsd.org>
8 *
9 * Provided that these terms and disclaimer and all copyright notices
10 * are retained or reproduced in an accompanying document, permission
11 * is granted to deal in this work without restriction, including un-
12 * limited rights to use, publicly perform, distribute, sell, modify,
13 * merge, give away, or sublicence.
14 *
15 * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
16 * the utmost extent permitted by applicable law, neither express nor
17 * implied; without malicious intent or gross negligence. In no event
18 * may a licensor, author or contributor be held liable for indirect,
19 * direct, other damage, loss, or other issues arising in any way out
20 * of dealing in the work, even if advised of the possibility of such
21 * damage or existence of a defect, except proven that it results out
22 * of said person's immediate fault when using the work as intended.
23 */
24
25 #include "sh.h"
26 #if !HAVE_GETRUSAGE
27 #include <sys/times.h>
28 #endif
29 #if HAVE_GRP_H
30 #include <grp.h>
31 #endif
32
33 __RCSID("$MirOS: src/bin/mksh/misc.c,v 1.219 2014/01/05 21:57:27 tg Exp $");
34
35 #define KSH_CHVT_FLAG
36 #ifdef MKSH_SMALL
37 #undef KSH_CHVT_FLAG
38 #endif
39 #ifdef TIOCSCTTY
40 #define KSH_CHVT_CODE
41 #define KSH_CHVT_FLAG
42 #endif
43 #ifdef MKSH_LEGACY_MODE
44 #undef KSH_CHVT_CODE
45 #undef KSH_CHVT_FLAG
46 #endif
47
48 /* type bits for unsigned char */
49 unsigned char chtypes[UCHAR_MAX + 1];
50
51 static const unsigned char *pat_scan(const unsigned char *,
52 const unsigned char *, bool) MKSH_A_PURE;
53 static int do_gmatch(const unsigned char *, const unsigned char *,
54 const unsigned char *, const unsigned char *) MKSH_A_PURE;
55 static const unsigned char *cclass(const unsigned char *, unsigned char)
56 MKSH_A_PURE;
57 #ifdef KSH_CHVT_CODE
58 static void chvt(const Getopt *);
59 #endif
60
61 /*XXX this should go away */
62 static int make_path(const char *, const char *, char **, XString *, int *);
63
64 #ifdef SETUID_CAN_FAIL_WITH_EAGAIN
65 /* we don't need to check for other codes, EPERM won't happen */
66 #define DO_SETUID(func, argvec) do { \
67 if ((func argvec) && errno == EAGAIN) \
68 errorf("%s failed with EAGAIN, probably due to a" \
69 " too low process limit; aborting", #func); \
70 } while (/* CONSTCOND */ 0)
71 #else
72 #define DO_SETUID(func, argvec) func argvec
73 #endif
74
75 /*
76 * Fast character classes
77 */
78 void
setctypes(const char * s,int t)79 setctypes(const char *s, int t)
80 {
81 unsigned int i;
82
83 if (t & C_IFS) {
84 for (i = 0; i < UCHAR_MAX + 1; i++)
85 chtypes[i] &= ~C_IFS;
86 /* include \0 in C_IFS */
87 chtypes[0] |= C_IFS;
88 }
89 while (*s != 0)
90 chtypes[(unsigned char)*s++] |= t;
91 }
92
93 void
initctypes(void)94 initctypes(void)
95 {
96 int c;
97
98 for (c = 'a'; c <= 'z'; c++)
99 chtypes[c] |= C_ALPHA;
100 for (c = 'A'; c <= 'Z'; c++)
101 chtypes[c] |= C_ALPHA;
102 chtypes['_'] |= C_ALPHA;
103 setctypes("0123456789", C_DIGIT);
104 /* \0 added automatically */
105 setctypes(TC_LEX1, C_LEX1);
106 setctypes("*@#!$-?", C_VAR1);
107 setctypes(TC_IFSWS, C_IFSWS);
108 setctypes("=-+?", C_SUBOP1);
109 setctypes("\t\n \"#$&'()*;<=>?[\\]`|", C_QUOTE);
110 }
111
112 /* called from XcheckN() to grow buffer */
113 char *
Xcheck_grow(XString * xsp,const char * xp,size_t more)114 Xcheck_grow(XString *xsp, const char *xp, size_t more)
115 {
116 const char *old_beg = xsp->beg;
117
118 if (more < xsp->len)
119 more = xsp->len;
120 /* (xsp->len + X_EXTRA) never overflows */
121 checkoktoadd(more, xsp->len + X_EXTRA);
122 xsp->beg = aresize(xsp->beg, (xsp->len += more) + X_EXTRA, xsp->areap);
123 xsp->end = xsp->beg + xsp->len;
124 return (xsp->beg + (xp - old_beg));
125 }
126
127
128 #define SHFLAGS_DEFNS
129 #include "sh_flags.gen"
130
131 #define OFC(i) (options[i][-2])
132 #define OFF(i) (((const unsigned char *)options[i])[-1])
133 #define OFN(i) (options[i])
134
135 const char * const options[] = {
136 #define SHFLAGS_ITEMS
137 #include "sh_flags.gen"
138 };
139
140 /*
141 * translate -o option into F* constant (also used for test -o option)
142 */
143 size_t
option(const char * n)144 option(const char *n)
145 {
146 size_t i = 0;
147
148 if ((n[0] == '-' || n[0] == '+') && n[1] && !n[2])
149 while (i < NELEM(options)) {
150 if (OFC(i) == n[1])
151 return (i);
152 ++i;
153 }
154 else
155 while (i < NELEM(options)) {
156 if (!strcmp(OFN(i), n))
157 return (i);
158 ++i;
159 }
160
161 return ((size_t)-1);
162 }
163
164 struct options_info {
165 int opt_width;
166 int opts[NELEM(options)];
167 };
168
169 static char *options_fmt_entry(char *, size_t, unsigned int, const void *);
170 static void printoptions(bool);
171
172 /* format a single select menu item */
173 static char *
options_fmt_entry(char * buf,size_t buflen,unsigned int i,const void * arg)174 options_fmt_entry(char *buf, size_t buflen, unsigned int i, const void *arg)
175 {
176 const struct options_info *oi = (const struct options_info *)arg;
177
178 shf_snprintf(buf, buflen, "%-*s %s",
179 oi->opt_width, OFN(oi->opts[i]),
180 Flag(oi->opts[i]) ? "on" : "off");
181 return (buf);
182 }
183
184 static void
printoptions(bool verbose)185 printoptions(bool verbose)
186 {
187 size_t i = 0;
188
189 if (verbose) {
190 size_t n = 0, len, octs = 0;
191 struct options_info oi;
192
193 /* verbose version */
194 shf_puts("Current option settings\n", shl_stdout);
195
196 oi.opt_width = 0;
197 while (i < NELEM(options)) {
198 if ((len = strlen(OFN(i)))) {
199 oi.opts[n++] = i;
200 if (len > octs)
201 octs = len;
202 len = utf_mbswidth(OFN(i));
203 if ((int)len > oi.opt_width)
204 oi.opt_width = (int)len;
205 }
206 ++i;
207 }
208 print_columns(shl_stdout, n, options_fmt_entry, &oi,
209 octs + 4, oi.opt_width + 4, true);
210 } else {
211 /* short version like AT&T ksh93 */
212 shf_puts(Tset, shl_stdout);
213 while (i < NELEM(options)) {
214 if (Flag(i) && OFN(i)[0])
215 shprintf(" -o %s", OFN(i));
216 ++i;
217 }
218 shf_putc('\n', shl_stdout);
219 }
220 }
221
222 char *
getoptions(void)223 getoptions(void)
224 {
225 size_t i = 0;
226 char c, m[(int)FNFLAGS + 1];
227 char *cp = m;
228
229 while (i < NELEM(options)) {
230 if ((c = OFC(i)) && Flag(i))
231 *cp++ = c;
232 ++i;
233 }
234 strndupx(cp, m, cp - m, ATEMP);
235 return (cp);
236 }
237
238 /* change a Flag(*) value; takes care of special actions */
239 void
change_flag(enum sh_flag f,int what,bool newset)240 change_flag(enum sh_flag f, int what, bool newset)
241 {
242 unsigned char oldval;
243 unsigned char newval = (newset ? 1 : 0);
244
245 if (f == FXTRACE) {
246 change_xtrace(newval, true);
247 return;
248 }
249 oldval = Flag(f);
250 Flag(f) = newval = (newset ? 1 : 0);
251 #ifndef MKSH_UNEMPLOYED
252 if (f == FMONITOR) {
253 if (what != OF_CMDLINE && newval != oldval)
254 j_change();
255 } else
256 #endif
257 #ifndef MKSH_NO_CMDLINE_EDITING
258 if ((
259 #if !MKSH_S_NOVI
260 f == FVI ||
261 #endif
262 f == FEMACS || f == FGMACS) && newval) {
263 #if !MKSH_S_NOVI
264 Flag(FVI) =
265 #endif
266 Flag(FEMACS) = Flag(FGMACS) = 0;
267 Flag(f) = newval;
268 } else
269 #endif
270 if (f == FPRIVILEGED && oldval && !newval) {
271 /* Turning off -p? */
272
273 /*XXX this can probably be optimised */
274 kshegid = kshgid = getgid();
275 ksheuid = kshuid = getuid();
276 #if HAVE_SETRESUGID
277 DO_SETUID(setresgid, (kshegid, kshegid, kshegid));
278 #if HAVE_SETGROUPS
279 /* setgroups doesn't EAGAIN on Linux */
280 setgroups(1, &kshegid);
281 #endif
282 DO_SETUID(setresuid, (ksheuid, ksheuid, ksheuid));
283 #else /* !HAVE_SETRESUGID */
284 /* seteuid, setegid, setgid don't EAGAIN on Linux */
285 #ifndef MKSH__NO_SETEUGID
286 seteuid(ksheuid);
287 #endif
288 DO_SETUID(setuid, (ksheuid));
289 #ifndef MKSH__NO_SETEUGID
290 setegid(kshegid);
291 #endif
292 setgid(kshegid);
293 #endif /* !HAVE_SETRESUGID */
294 } else if ((f == FPOSIX || f == FSH) && newval) {
295 /* Turning on -o posix or -o sh? */
296 Flag(FBRACEEXPAND) = 0;
297 } else if (f == FTALKING) {
298 /* Changing interactive flag? */
299 if ((what == OF_CMDLINE || what == OF_SET) && procpid == kshpid)
300 Flag(FTALKING_I) = newval;
301 }
302 }
303
304 void
change_xtrace(unsigned char newval,bool dosnapshot)305 change_xtrace(unsigned char newval, bool dosnapshot)
306 {
307 if (!dosnapshot && newval == Flag(FXTRACE))
308 return;
309
310 if (Flag(FXTRACE) == 2) {
311 shf_putc('\n', shl_xtrace);
312 Flag(FXTRACE) = 1;
313 shf_flush(shl_xtrace);
314 }
315
316 if (!dosnapshot && Flag(FXTRACE) == 1)
317 switch (newval) {
318 case 1:
319 return;
320 case 2:
321 goto changed_xtrace;
322 }
323
324 shf_flush(shl_xtrace);
325 if (shl_xtrace->fd != 2)
326 close(shl_xtrace->fd);
327 if (!newval || (shl_xtrace->fd = savefd(2)) == -1)
328 shl_xtrace->fd = 2;
329
330 changed_xtrace:
331 if ((Flag(FXTRACE) = newval) == 2)
332 shf_puts(substitute(str_val(global("PS4")), 0), shl_xtrace);
333 }
334
335 /*
336 * Parse command line and set command arguments. Returns the index of
337 * non-option arguments, -1 if there is an error.
338 */
339 int
parse_args(const char ** argv,int what,bool * setargsp)340 parse_args(const char **argv,
341 /* OF_CMDLINE or OF_SET */
342 int what,
343 bool *setargsp)
344 {
345 static const char cmd_opts[] =
346 #define SHFLAGS_NOT_SET
347 #define SHFLAGS_OPTCS
348 #include "sh_flags.gen"
349 #undef SHFLAGS_NOT_SET
350 ;
351 static const char set_opts[] =
352 #define SHFLAGS_NOT_CMD
353 #define SHFLAGS_OPTCS
354 #include "sh_flags.gen"
355 #undef SHFLAGS_NOT_CMD
356 ;
357 bool set;
358 const char *opts;
359 const char *array = NULL;
360 Getopt go;
361 size_t i;
362 int optc, arrayset = 0;
363 bool sortargs = false;
364 bool fcompatseen = false;
365
366 if (what == OF_CMDLINE) {
367 const char *p = argv[0], *q;
368 /*
369 * Set FLOGIN before parsing options so user can clear
370 * flag using +l.
371 */
372 if (*p != '-')
373 for (q = p; *q; )
374 if (*q++ == '/')
375 p = q;
376 Flag(FLOGIN) = (*p == '-');
377 opts = cmd_opts;
378 } else if (what == OF_FIRSTTIME) {
379 opts = cmd_opts;
380 } else
381 opts = set_opts;
382 ksh_getopt_reset(&go, GF_ERROR|GF_PLUSOPT);
383 while ((optc = ksh_getopt(argv, &go, opts)) != -1) {
384 set = tobool(!(go.info & GI_PLUS));
385 switch (optc) {
386 case 'A':
387 if (what == OF_FIRSTTIME)
388 break;
389 arrayset = set ? 1 : -1;
390 array = go.optarg;
391 break;
392
393 case 'o':
394 if (what == OF_FIRSTTIME)
395 break;
396 if (go.optarg == NULL) {
397 /*
398 * lone -o: print options
399 *
400 * Note that on the command line, -o requires
401 * an option (ie, can't get here if what is
402 * OF_CMDLINE).
403 */
404 printoptions(set);
405 break;
406 }
407 i = option(go.optarg);
408 if ((i == FPOSIX || i == FSH) && set && !fcompatseen) {
409 /*
410 * If running 'set -o posix' or
411 * 'set -o sh', turn off the other;
412 * if running 'set -o posix -o sh'
413 * allow both to be set though.
414 */
415 Flag(FPOSIX) = 0;
416 Flag(FSH) = 0;
417 fcompatseen = true;
418 }
419 if ((i != (size_t)-1) && (set ? 1U : 0U) == Flag(i))
420 /*
421 * Don't check the context if the flag
422 * isn't changing - makes "set -o interactive"
423 * work if you're already interactive. Needed
424 * if the output of "set +o" is to be used.
425 */
426 ;
427 else if ((i != (size_t)-1) && (OFF(i) & what))
428 change_flag((enum sh_flag)i, what, set);
429 else {
430 bi_errorf("%s: %s", go.optarg, "bad option");
431 return (-1);
432 }
433 break;
434
435 #ifdef KSH_CHVT_FLAG
436 case 'T':
437 if (what != OF_FIRSTTIME)
438 break;
439 #ifndef KSH_CHVT_CODE
440 errorf("no TIOCSCTTY ioctl");
441 #else
442 change_flag(FTALKING, OF_CMDLINE, true);
443 chvt(&go);
444 break;
445 #endif
446 #endif
447
448 case '?':
449 return (-1);
450
451 default:
452 if (what == OF_FIRSTTIME)
453 break;
454 /* -s: sort positional params (AT&T ksh stupidity) */
455 if (what == OF_SET && optc == 's') {
456 sortargs = true;
457 break;
458 }
459 for (i = 0; i < NELEM(options); i++)
460 if (optc == OFC(i) &&
461 (what & OFF(i))) {
462 change_flag((enum sh_flag)i, what, set);
463 break;
464 }
465 if (i == NELEM(options))
466 internal_errorf("parse_args: '%c'", optc);
467 }
468 }
469 if (!(go.info & GI_MINUSMINUS) && argv[go.optind] &&
470 (argv[go.optind][0] == '-' || argv[go.optind][0] == '+') &&
471 argv[go.optind][1] == '\0') {
472 /* lone - clears -v and -x flags */
473 if (argv[go.optind][0] == '-') {
474 Flag(FVERBOSE) = 0;
475 change_xtrace(0, false);
476 }
477 /* set skips lone - or + option */
478 go.optind++;
479 }
480 if (setargsp)
481 /* -- means set $#/$* even if there are no arguments */
482 *setargsp = !arrayset && ((go.info & GI_MINUSMINUS) ||
483 argv[go.optind]);
484
485 if (arrayset) {
486 const char *ccp = NULL;
487
488 mkssert(array != NULL);
489 if (*array)
490 ccp = skip_varname(array, false);
491 if (!ccp || !(!ccp[0] || (ccp[0] == '+' && !ccp[1]))) {
492 bi_errorf("%s: %s", array, "is not an identifier");
493 return (-1);
494 }
495 }
496 if (sortargs) {
497 for (i = go.optind; argv[i]; i++)
498 ;
499 qsort(&argv[go.optind], i - go.optind, sizeof(void *),
500 xstrcmp);
501 }
502 if (arrayset)
503 go.optind += set_array(array, tobool(arrayset > 0),
504 argv + go.optind);
505
506 return (go.optind);
507 }
508
509 /* parse a decimal number: returns 0 if string isn't a number, 1 otherwise */
510 int
getn(const char * s,int * ai)511 getn(const char *s, int *ai)
512 {
513 char c;
514 mksh_ari_u num;
515 bool neg = false;
516
517 num.u = 0;
518
519 do {
520 c = *s++;
521 } while (ksh_isspace(c));
522
523 switch (c) {
524 case '-':
525 neg = true;
526 /* FALLTHROUGH */
527 case '+':
528 c = *s++;
529 break;
530 }
531
532 do {
533 if (!ksh_isdigit(c))
534 /* not numeric */
535 return (0);
536 if (num.u > 214748364U)
537 /* overflow on multiplication */
538 return (0);
539 num.u = num.u * 10U + (unsigned int)(c - '0');
540 /* now: num.u <= 2147483649U */
541 } while ((c = *s++));
542
543 if (num.u > (neg ? 2147483648U : 2147483647U))
544 /* overflow for signed 32-bit int */
545 return (0);
546
547 if (neg)
548 num.u = -num.u;
549 *ai = num.i;
550 return (1);
551 }
552
553 /**
554 * pattern simplifications:
555 * - @(x) -> x (not @(x|y) though)
556 * - ** -> *
557 */
558 static void *
simplify_gmatch_pattern(const unsigned char * sp)559 simplify_gmatch_pattern(const unsigned char *sp)
560 {
561 uint8_t c;
562 unsigned char *cp, *dp;
563 const unsigned char *ps, *se;
564
565 cp = alloc(strlen((const void *)sp) + 1, ATEMP);
566 goto simplify_gmatch_pat1a;
567
568 /* foo@(b@(a)r)b@(a|a)z -> foobarb@(a|a)z */
569 simplify_gmatch_pat1:
570 sp = cp;
571 simplify_gmatch_pat1a:
572 dp = cp;
573 se = sp + strlen((const void *)sp);
574 while ((c = *sp++)) {
575 if (!ISMAGIC(c)) {
576 *dp++ = c;
577 continue;
578 }
579 switch ((c = *sp++)) {
580 case 0x80|'@':
581 /* simile for @ */
582 case 0x80|' ':
583 /* check whether it has only one clause */
584 ps = pat_scan(sp, se, true);
585 if (!ps || ps[-1] != /*(*/ ')')
586 /* nope */
587 break;
588 /* copy inner clause until matching close */
589 ps -= 2;
590 while ((const unsigned char *)sp < ps)
591 *dp++ = *sp++;
592 /* skip MAGIC and closing parenthesis */
593 sp += 2;
594 /* copy the rest of the pattern */
595 memmove(dp, sp, strlen((const void *)sp) + 1);
596 /* redo from start */
597 goto simplify_gmatch_pat1;
598 }
599 *dp++ = MAGIC;
600 *dp++ = c;
601 }
602 *dp = '\0';
603
604 /* collapse adjacent asterisk wildcards */
605 sp = dp = cp;
606 while ((c = *sp++)) {
607 if (!ISMAGIC(c)) {
608 *dp++ = c;
609 continue;
610 }
611 switch ((c = *sp++)) {
612 case '*':
613 while (ISMAGIC(sp[0]) && sp[1] == c)
614 sp += 2;
615 break;
616 }
617 *dp++ = MAGIC;
618 *dp++ = c;
619 }
620 *dp = '\0';
621
622 /* return the result, allocated from ATEMP */
623 return (cp);
624 }
625
626 /* -------- gmatch.c -------- */
627
628 /*
629 * int gmatch(string, pattern)
630 * char *string, *pattern;
631 *
632 * Match a pattern as in sh(1).
633 * pattern character are prefixed with MAGIC by expand.
634 */
635 int
gmatchx(const char * s,const char * p,bool isfile)636 gmatchx(const char *s, const char *p, bool isfile)
637 {
638 const char *se, *pe;
639 char *pnew;
640 int rv;
641
642 if (s == NULL || p == NULL)
643 return (0);
644
645 se = s + strlen(s);
646 pe = p + strlen(p);
647 /*
648 * isfile is false iff no syntax check has been done on
649 * the pattern. If check fails, just to a strcmp().
650 */
651 if (!isfile && !has_globbing(p, pe)) {
652 size_t len = pe - p + 1;
653 char tbuf[64];
654 char *t = len <= sizeof(tbuf) ? tbuf : alloc(len, ATEMP);
655 debunk(t, p, len);
656 return (!strcmp(t, s));
657 }
658
659 /*
660 * since the do_gmatch() engine sucks so much, we must do some
661 * pattern simplifications
662 */
663 pnew = simplify_gmatch_pattern((const unsigned char *)p);
664 pe = pnew + strlen(pnew);
665
666 rv = do_gmatch((const unsigned char *)s, (const unsigned char *)se,
667 (const unsigned char *)pnew, (const unsigned char *)pe);
668 afree(pnew, ATEMP);
669 return (rv);
670 }
671
672 /**
673 * Returns if p is a syntacticly correct globbing pattern, false
674 * if it contains no pattern characters or if there is a syntax error.
675 * Syntax errors are:
676 * - [ with no closing ]
677 * - imbalanced $(...) expression
678 * - [...] and *(...) not nested (eg, [a$(b|]c), *(a[b|c]d))
679 */
680 /*XXX
681 * - if no magic,
682 * if dest given, copy to dst
683 * return ?
684 * - if magic && (no globbing || syntax error)
685 * debunk to dst
686 * return ?
687 * - return ?
688 */
689 int
has_globbing(const char * xp,const char * xpe)690 has_globbing(const char *xp, const char *xpe)
691 {
692 const unsigned char *p = (const unsigned char *) xp;
693 const unsigned char *pe = (const unsigned char *) xpe;
694 int c;
695 int nest = 0, bnest = 0;
696 bool saw_glob = false;
697 /* inside [...] */
698 bool in_bracket = false;
699
700 for (; p < pe; p++) {
701 if (!ISMAGIC(*p))
702 continue;
703 if ((c = *++p) == '*' || c == '?')
704 saw_glob = true;
705 else if (c == '[') {
706 if (!in_bracket) {
707 saw_glob = true;
708 in_bracket = true;
709 if (ISMAGIC(p[1]) && p[2] == '!')
710 p += 2;
711 if (ISMAGIC(p[1]) && p[2] == ']')
712 p += 2;
713 }
714 /*XXX Do we need to check ranges here? POSIX Q */
715 } else if (c == ']') {
716 if (in_bracket) {
717 if (bnest)
718 /* [a*(b]) */
719 return (0);
720 in_bracket = false;
721 }
722 } else if ((c & 0x80) && vstrchr("*+?@! ", c & 0x7f)) {
723 saw_glob = true;
724 if (in_bracket)
725 bnest++;
726 else
727 nest++;
728 } else if (c == '|') {
729 if (in_bracket && !bnest)
730 /* *(a[foo|bar]) */
731 return (0);
732 } else if (c == /*(*/ ')') {
733 if (in_bracket) {
734 if (!bnest--)
735 /* *(a[b)c] */
736 return (0);
737 } else if (nest)
738 nest--;
739 }
740 /*
741 * else must be a MAGIC-MAGIC, or MAGIC-!,
742 * MAGIC--, MAGIC-], MAGIC-{, MAGIC-, MAGIC-}
743 */
744 }
745 return (saw_glob && !in_bracket && !nest);
746 }
747
748 /* Function must return either 0 or 1 (assumed by code for 0x80|'!') */
749 static int
do_gmatch(const unsigned char * s,const unsigned char * se,const unsigned char * p,const unsigned char * pe)750 do_gmatch(const unsigned char *s, const unsigned char *se,
751 const unsigned char *p, const unsigned char *pe)
752 {
753 unsigned char sc, pc;
754 const unsigned char *prest, *psub, *pnext;
755 const unsigned char *srest;
756
757 if (s == NULL || p == NULL)
758 return (0);
759 while (p < pe) {
760 pc = *p++;
761 sc = s < se ? *s : '\0';
762 s++;
763 if (!ISMAGIC(pc)) {
764 if (sc != pc)
765 return (0);
766 continue;
767 }
768 switch (*p++) {
769 case '[':
770 if (sc == 0 || (p = cclass(p, sc)) == NULL)
771 return (0);
772 break;
773
774 case '?':
775 if (sc == 0)
776 return (0);
777 if (UTFMODE) {
778 --s;
779 s += utf_ptradj((const void *)s);
780 }
781 break;
782
783 case '*':
784 if (p == pe)
785 return (1);
786 s--;
787 do {
788 if (do_gmatch(s, se, p, pe))
789 return (1);
790 } while (s++ < se);
791 return (0);
792
793 /**
794 * [*+?@!](pattern|pattern|..)
795 * This is also needed for ${..%..}, etc.
796 */
797
798 /* matches one or more times */
799 case 0x80|'+':
800 /* matches zero or more times */
801 case 0x80|'*':
802 if (!(prest = pat_scan(p, pe, false)))
803 return (0);
804 s--;
805 /* take care of zero matches */
806 if (p[-1] == (0x80 | '*') &&
807 do_gmatch(s, se, prest, pe))
808 return (1);
809 for (psub = p; ; psub = pnext) {
810 pnext = pat_scan(psub, pe, true);
811 for (srest = s; srest <= se; srest++) {
812 if (do_gmatch(s, srest, psub, pnext - 2) &&
813 (do_gmatch(srest, se, prest, pe) ||
814 (s != srest && do_gmatch(srest,
815 se, p - 2, pe))))
816 return (1);
817 }
818 if (pnext == prest)
819 break;
820 }
821 return (0);
822
823 /* matches zero or once */
824 case 0x80|'?':
825 /* matches one of the patterns */
826 case 0x80|'@':
827 /* simile for @ */
828 case 0x80|' ':
829 if (!(prest = pat_scan(p, pe, false)))
830 return (0);
831 s--;
832 /* Take care of zero matches */
833 if (p[-1] == (0x80 | '?') &&
834 do_gmatch(s, se, prest, pe))
835 return (1);
836 for (psub = p; ; psub = pnext) {
837 pnext = pat_scan(psub, pe, true);
838 srest = prest == pe ? se : s;
839 for (; srest <= se; srest++) {
840 if (do_gmatch(s, srest, psub, pnext - 2) &&
841 do_gmatch(srest, se, prest, pe))
842 return (1);
843 }
844 if (pnext == prest)
845 break;
846 }
847 return (0);
848
849 /* matches none of the patterns */
850 case 0x80|'!':
851 if (!(prest = pat_scan(p, pe, false)))
852 return (0);
853 s--;
854 for (srest = s; srest <= se; srest++) {
855 int matched = 0;
856
857 for (psub = p; ; psub = pnext) {
858 pnext = pat_scan(psub, pe, true);
859 if (do_gmatch(s, srest, psub,
860 pnext - 2)) {
861 matched = 1;
862 break;
863 }
864 if (pnext == prest)
865 break;
866 }
867 if (!matched &&
868 do_gmatch(srest, se, prest, pe))
869 return (1);
870 }
871 return (0);
872
873 default:
874 if (sc != p[-1])
875 return (0);
876 break;
877 }
878 }
879 return (s == se);
880 }
881
882 static const unsigned char *
cclass(const unsigned char * p,unsigned char sub)883 cclass(const unsigned char *p, unsigned char sub)
884 {
885 unsigned char c, d;
886 bool notp, found = false;
887 const unsigned char *orig_p = p;
888
889 if ((notp = tobool(ISMAGIC(*p) && *++p == '!')))
890 p++;
891 do {
892 c = *p++;
893 if (ISMAGIC(c)) {
894 c = *p++;
895 if ((c & 0x80) && !ISMAGIC(c)) {
896 /* extended pattern matching: *+?@! */
897 c &= 0x7F;
898 /* XXX the ( char isn't handled as part of [] */
899 if (c == ' ')
900 /* simile for @: plain (..) */
901 c = '(' /*)*/;
902 }
903 }
904 if (c == '\0')
905 /* No closing ] - act as if the opening [ was quoted */
906 return (sub == '[' ? orig_p : NULL);
907 if (ISMAGIC(p[0]) && p[1] == '-' &&
908 (!ISMAGIC(p[2]) || p[3] != ']')) {
909 /* MAGIC- */
910 p += 2;
911 d = *p++;
912 if (ISMAGIC(d)) {
913 d = *p++;
914 if ((d & 0x80) && !ISMAGIC(d))
915 d &= 0x7f;
916 }
917 /* POSIX says this is an invalid expression */
918 if (c > d)
919 return (NULL);
920 } else
921 d = c;
922 if (c == sub || (c <= sub && sub <= d))
923 found = true;
924 } while (!(ISMAGIC(p[0]) && p[1] == ']'));
925
926 return ((found != notp) ? p+2 : NULL);
927 }
928
929 /* Look for next ) or | (if match_sep) in *(foo|bar) pattern */
930 static const unsigned char *
pat_scan(const unsigned char * p,const unsigned char * pe,bool match_sep)931 pat_scan(const unsigned char *p, const unsigned char *pe, bool match_sep)
932 {
933 int nest = 0;
934
935 for (; p < pe; p++) {
936 if (!ISMAGIC(*p))
937 continue;
938 if ((*++p == /*(*/ ')' && nest-- == 0) ||
939 (*p == '|' && match_sep && nest == 0))
940 return (p + 1);
941 if ((*p & 0x80) && vstrchr("*+?@! ", *p & 0x7f))
942 nest++;
943 }
944 return (NULL);
945 }
946
947 int
xstrcmp(const void * p1,const void * p2)948 xstrcmp(const void *p1, const void *p2)
949 {
950 return (strcmp(*(const char * const *)p1, *(const char * const *)p2));
951 }
952
953 /* Initialise a Getopt structure */
954 void
ksh_getopt_reset(Getopt * go,int flags)955 ksh_getopt_reset(Getopt *go, int flags)
956 {
957 go->optind = 1;
958 go->optarg = NULL;
959 go->p = 0;
960 go->flags = flags;
961 go->info = 0;
962 go->buf[1] = '\0';
963 }
964
965
966 /**
967 * getopt() used for shell built-in commands, the getopts command, and
968 * command line options.
969 * A leading ':' in options means don't print errors, instead return '?'
970 * or ':' and set go->optarg to the offending option character.
971 * If GF_ERROR is set (and option doesn't start with :), errors result in
972 * a call to bi_errorf().
973 *
974 * Non-standard features:
975 * - ';' is like ':' in options, except the argument is optional
976 * (if it isn't present, optarg is set to 0).
977 * Used for 'set -o'.
978 * - ',' is like ':' in options, except the argument always immediately
979 * follows the option character (optarg is set to the null string if
980 * the option is missing).
981 * Used for 'read -u2', 'print -u2' and fc -40.
982 * - '#' is like ':' in options, expect that the argument is optional
983 * and must start with a digit. If the argument doesn't start with a
984 * digit, it is assumed to be missing and normal option processing
985 * continues (optarg is set to 0 if the option is missing).
986 * Used for 'typeset -LZ4'.
987 * - accepts +c as well as -c IF the GF_PLUSOPT flag is present. If an
988 * option starting with + is accepted, the GI_PLUS flag will be set
989 * in go->info.
990 */
991 int
ksh_getopt(const char ** argv,Getopt * go,const char * optionsp)992 ksh_getopt(const char **argv, Getopt *go, const char *optionsp)
993 {
994 char c;
995 const char *o;
996
997 if (go->p == 0 || (c = argv[go->optind - 1][go->p]) == '\0') {
998 const char *arg = argv[go->optind], flag = arg ? *arg : '\0';
999
1000 go->p = 1;
1001 if (flag == '-' && arg[1] == '-' && arg[2] == '\0') {
1002 go->optind++;
1003 go->p = 0;
1004 go->info |= GI_MINUSMINUS;
1005 return (-1);
1006 }
1007 if (arg == NULL ||
1008 ((flag != '-' ) &&
1009 /* neither a - nor a + (if + allowed) */
1010 (!(go->flags & GF_PLUSOPT) || flag != '+')) ||
1011 (c = arg[1]) == '\0') {
1012 go->p = 0;
1013 return (-1);
1014 }
1015 go->optind++;
1016 go->info &= ~(GI_MINUS|GI_PLUS);
1017 go->info |= flag == '-' ? GI_MINUS : GI_PLUS;
1018 }
1019 go->p++;
1020 if (c == '?' || c == ':' || c == ';' || c == ',' || c == '#' ||
1021 !(o = cstrchr(optionsp, c))) {
1022 if (optionsp[0] == ':') {
1023 go->buf[0] = c;
1024 go->optarg = go->buf;
1025 } else {
1026 warningf(true, "%s%s-%c: %s",
1027 (go->flags & GF_NONAME) ? "" : argv[0],
1028 (go->flags & GF_NONAME) ? "" : ": ", c,
1029 "unknown option");
1030 if (go->flags & GF_ERROR)
1031 bi_errorfz();
1032 }
1033 return ('?');
1034 }
1035 /**
1036 * : means argument must be present, may be part of option argument
1037 * or the next argument
1038 * ; same as : but argument may be missing
1039 * , means argument is part of option argument, and may be null.
1040 */
1041 if (*++o == ':' || *o == ';') {
1042 if (argv[go->optind - 1][go->p])
1043 go->optarg = argv[go->optind - 1] + go->p;
1044 else if (argv[go->optind])
1045 go->optarg = argv[go->optind++];
1046 else if (*o == ';')
1047 go->optarg = NULL;
1048 else {
1049 if (optionsp[0] == ':') {
1050 go->buf[0] = c;
1051 go->optarg = go->buf;
1052 return (':');
1053 }
1054 warningf(true, "%s%s-%c: %s",
1055 (go->flags & GF_NONAME) ? "" : argv[0],
1056 (go->flags & GF_NONAME) ? "" : ": ", c,
1057 "requires an argument");
1058 if (go->flags & GF_ERROR)
1059 bi_errorfz();
1060 return ('?');
1061 }
1062 go->p = 0;
1063 } else if (*o == ',') {
1064 /* argument is attached to option character, even if null */
1065 go->optarg = argv[go->optind - 1] + go->p;
1066 go->p = 0;
1067 } else if (*o == '#') {
1068 /*
1069 * argument is optional and may be attached or unattached
1070 * but must start with a digit. optarg is set to 0 if the
1071 * argument is missing.
1072 */
1073 if (argv[go->optind - 1][go->p]) {
1074 if (ksh_isdigit(argv[go->optind - 1][go->p])) {
1075 go->optarg = argv[go->optind - 1] + go->p;
1076 go->p = 0;
1077 } else
1078 go->optarg = NULL;
1079 } else {
1080 if (argv[go->optind] && ksh_isdigit(argv[go->optind][0])) {
1081 go->optarg = argv[go->optind++];
1082 go->p = 0;
1083 } else
1084 go->optarg = NULL;
1085 }
1086 }
1087 return (c);
1088 }
1089
1090 /*
1091 * print variable/alias value using necessary quotes
1092 * (POSIX says they should be suitable for re-entry...)
1093 * No trailing newline is printed.
1094 */
1095 void
print_value_quoted(struct shf * shf,const char * s)1096 print_value_quoted(struct shf *shf, const char *s)
1097 {
1098 unsigned char c;
1099 const unsigned char *p = (const unsigned char *)s;
1100 bool inquote = true;
1101
1102 /* first, check whether any quotes are needed */
1103 while ((c = *p++) >= 32)
1104 if (ctype(c, C_QUOTE))
1105 inquote = false;
1106
1107 p = (const unsigned char *)s;
1108 if (c == 0) {
1109 if (inquote) {
1110 /* nope, use the shortcut */
1111 shf_puts(s, shf);
1112 return;
1113 }
1114
1115 /* otherwise, quote nicely via state machine */
1116 while ((c = *p++) != 0) {
1117 if (c == '\'') {
1118 /*
1119 * multiple single quotes or any of them
1120 * at the beginning of a string look nicer
1121 * this way than when simply substituting
1122 */
1123 if (inquote) {
1124 shf_putc('\'', shf);
1125 inquote = false;
1126 }
1127 shf_putc('\\', shf);
1128 } else if (!inquote) {
1129 shf_putc('\'', shf);
1130 inquote = true;
1131 }
1132 shf_putc(c, shf);
1133 }
1134 } else {
1135 unsigned int wc;
1136 size_t n;
1137
1138 /* use $'...' quote format */
1139 shf_putc('$', shf);
1140 shf_putc('\'', shf);
1141 while ((c = *p) != 0) {
1142 if (c >= 0xC2) {
1143 n = utf_mbtowc(&wc, (const char *)p);
1144 if (n != (size_t)-1) {
1145 p += n;
1146 shf_fprintf(shf, "\\u%04X", wc);
1147 continue;
1148 }
1149 }
1150 ++p;
1151 switch (c) {
1152 /* see unbksl() in this file for comments */
1153 case 7:
1154 c = 'a';
1155 if (0)
1156 /* FALLTHROUGH */
1157 case '\b':
1158 c = 'b';
1159 if (0)
1160 /* FALLTHROUGH */
1161 case '\f':
1162 c = 'f';
1163 if (0)
1164 /* FALLTHROUGH */
1165 case '\n':
1166 c = 'n';
1167 if (0)
1168 /* FALLTHROUGH */
1169 case '\r':
1170 c = 'r';
1171 if (0)
1172 /* FALLTHROUGH */
1173 case '\t':
1174 c = 't';
1175 if (0)
1176 /* FALLTHROUGH */
1177 case 11:
1178 c = 'v';
1179 if (0)
1180 /* FALLTHROUGH */
1181 case '\033':
1182 /* take E not e because \e is \ in *roff */
1183 c = 'E';
1184 /* FALLTHROUGH */
1185 case '\\':
1186 shf_putc('\\', shf);
1187
1188 if (0)
1189 /* FALLTHROUGH */
1190 default:
1191 if (c < 32 || c > 0x7E) {
1192 /* FALLTHROUGH */
1193 case '\'':
1194 shf_fprintf(shf, "\\%03o", c);
1195 break;
1196 }
1197
1198 shf_putc(c, shf);
1199 break;
1200 }
1201 }
1202 inquote = true;
1203 }
1204 if (inquote)
1205 shf_putc('\'', shf);
1206 }
1207
1208 /*
1209 * Print things in columns and rows - func() is called to format
1210 * the i-th element
1211 */
1212 void
print_columns(struct shf * shf,unsigned int n,char * (* func)(char *,size_t,unsigned int,const void *),const void * arg,size_t max_oct,size_t max_colz,bool prefcol)1213 print_columns(struct shf *shf, unsigned int n,
1214 char *(*func)(char *, size_t, unsigned int, const void *),
1215 const void *arg, size_t max_oct, size_t max_colz, bool prefcol)
1216 {
1217 unsigned int i, r, c, rows, cols, nspace, max_col;
1218 char *str;
1219
1220 if (!n)
1221 return;
1222
1223 if (max_colz > 2147483646) {
1224 #ifndef MKSH_SMALL
1225 internal_warningf("print_columns called with %s=%zu >= INT_MAX",
1226 "max_col", max_colz);
1227 #endif
1228 return;
1229 }
1230 max_col = (unsigned int)max_colz;
1231
1232 if (max_oct > 2147483646) {
1233 #ifndef MKSH_SMALL
1234 internal_warningf("print_columns called with %s=%zu >= INT_MAX",
1235 "max_oct", max_oct);
1236 #endif
1237 return;
1238 }
1239 ++max_oct;
1240 str = alloc(max_oct, ATEMP);
1241
1242 /*
1243 * We use (max_col + 1) to consider the space separator.
1244 * Note that no space is printed after the last column
1245 * to avoid problems with terminals that have auto-wrap.
1246 */
1247 cols = x_cols / (max_col + 1);
1248
1249 /* if we can only print one column anyway, skip the goo */
1250 if (cols < 2) {
1251 for (i = 0; i < n; ++i)
1252 shf_fprintf(shf, "%s\n",
1253 (*func)(str, max_oct, i, arg));
1254 goto out;
1255 }
1256
1257 rows = (n + cols - 1) / cols;
1258 if (prefcol && cols > rows) {
1259 cols = rows;
1260 rows = (n + cols - 1) / cols;
1261 }
1262
1263 nspace = (x_cols - max_col * cols) / cols;
1264 max_col = -max_col;
1265 if (nspace <= 0)
1266 nspace = 1;
1267 for (r = 0; r < rows; r++) {
1268 for (c = 0; c < cols; c++) {
1269 i = c * rows + r;
1270 if (i < n) {
1271 shf_fprintf(shf, "%*s", max_col,
1272 (*func)(str, max_oct, i, arg));
1273 if (c + 1 < cols)
1274 shf_fprintf(shf, "%*s", nspace, null);
1275 }
1276 }
1277 shf_putchar('\n', shf);
1278 }
1279 out:
1280 afree(str, ATEMP);
1281 }
1282
1283 /* Strip any nul bytes from buf - returns new length (nbytes - # of nuls) */
1284 void
strip_nuls(char * buf,int nbytes)1285 strip_nuls(char *buf, int nbytes)
1286 {
1287 char *dst;
1288
1289 /*
1290 * nbytes check because some systems (older FreeBSDs) have a
1291 * buggy memchr()
1292 */
1293 if (nbytes && (dst = memchr(buf, '\0', nbytes))) {
1294 char *end = buf + nbytes;
1295 char *p, *q;
1296
1297 for (p = dst; p < end; p = q) {
1298 /* skip a block of nulls */
1299 while (++p < end && *p == '\0')
1300 ;
1301 /* find end of non-null block */
1302 if (!(q = memchr(p, '\0', end - p)))
1303 q = end;
1304 memmove(dst, p, q - p);
1305 dst += q - p;
1306 }
1307 *dst = '\0';
1308 }
1309 }
1310
1311 /*
1312 * Like read(2), but if read fails due to non-blocking flag,
1313 * resets flag and restarts read.
1314 */
1315 ssize_t
blocking_read(int fd,char * buf,size_t nbytes)1316 blocking_read(int fd, char *buf, size_t nbytes)
1317 {
1318 ssize_t ret;
1319 bool tried_reset = false;
1320
1321 while ((ret = read(fd, buf, nbytes)) < 0) {
1322 if (!tried_reset && errno == EAGAIN) {
1323 if (reset_nonblock(fd) > 0) {
1324 tried_reset = true;
1325 continue;
1326 }
1327 errno = EAGAIN;
1328 }
1329 break;
1330 }
1331 return (ret);
1332 }
1333
1334 /*
1335 * Reset the non-blocking flag on the specified file descriptor.
1336 * Returns -1 if there was an error, 0 if non-blocking wasn't set,
1337 * 1 if it was.
1338 */
1339 int
reset_nonblock(int fd)1340 reset_nonblock(int fd)
1341 {
1342 int flags;
1343
1344 if ((flags = fcntl(fd, F_GETFL, 0)) < 0)
1345 return (-1);
1346 if (!(flags & O_NONBLOCK))
1347 return (0);
1348 flags &= ~O_NONBLOCK;
1349 if (fcntl(fd, F_SETFL, flags) < 0)
1350 return (-1);
1351 return (1);
1352 }
1353
1354 /* getcwd(3) equivalent, allocates from ATEMP but doesn't resize */
1355 char *
ksh_get_wd(void)1356 ksh_get_wd(void)
1357 {
1358 #ifdef MKSH__NO_PATH_MAX
1359 char *rv, *cp;
1360
1361 if ((cp = get_current_dir_name())) {
1362 strdupx(rv, cp, ATEMP);
1363 free_gnu_gcdn(cp);
1364 } else
1365 rv = NULL;
1366 #else
1367 char *rv;
1368
1369 if (!getcwd((rv = alloc(PATH_MAX + 1, ATEMP)), PATH_MAX)) {
1370 afree(rv, ATEMP);
1371 rv = NULL;
1372 }
1373 #endif
1374
1375 return (rv);
1376 }
1377
1378 #ifndef ELOOP
1379 #define ELOOP E2BIG
1380 #endif
1381
1382 char *
do_realpath(const char * upath)1383 do_realpath(const char *upath)
1384 {
1385 char *xp, *ip, *tp, *ipath, *ldest = NULL;
1386 XString xs;
1387 ptrdiff_t pos;
1388 size_t len;
1389 int llen;
1390 struct stat sb;
1391 #ifdef MKSH__NO_PATH_MAX
1392 size_t ldestlen = 0;
1393 #define pathlen sb.st_size
1394 #define pathcnd (ldestlen < (pathlen + 1))
1395 #else
1396 #define pathlen PATH_MAX
1397 #define pathcnd (!ldest)
1398 #endif
1399 /* max. recursion depth */
1400 int symlinks = 32;
1401
1402 if (upath[0] == '/') {
1403 /* upath is an absolute pathname */
1404 strdupx(ipath, upath, ATEMP);
1405 } else {
1406 /* upath is a relative pathname, prepend cwd */
1407 if ((tp = ksh_get_wd()) == NULL || tp[0] != '/')
1408 return (NULL);
1409 ipath = shf_smprintf("%s%s%s", tp, "/", upath);
1410 afree(tp, ATEMP);
1411 }
1412
1413 /* ipath and upath are in memory at the same time -> unchecked */
1414 Xinit(xs, xp, strlen(ip = ipath) + 1, ATEMP);
1415
1416 /* now jump into the deep of the loop */
1417 goto beginning_of_a_pathname;
1418
1419 while (*ip) {
1420 /* skip slashes in input */
1421 while (*ip == '/')
1422 ++ip;
1423 if (!*ip)
1424 break;
1425
1426 /* get next pathname component from input */
1427 tp = ip;
1428 while (*ip && *ip != '/')
1429 ++ip;
1430 len = ip - tp;
1431
1432 /* check input for "." and ".." */
1433 if (tp[0] == '.') {
1434 if (len == 1)
1435 /* just continue with the next one */
1436 continue;
1437 else if (len == 2 && tp[1] == '.') {
1438 /* strip off last pathname component */
1439 while (xp > Xstring(xs, xp))
1440 if (*--xp == '/')
1441 break;
1442 /* then continue with the next one */
1443 continue;
1444 }
1445 }
1446
1447 /* store output position away, then append slash to output */
1448 pos = Xsavepos(xs, xp);
1449 /* 1 for the '/' and len + 1 for tp and the NUL from below */
1450 XcheckN(xs, xp, 1 + len + 1);
1451 Xput(xs, xp, '/');
1452
1453 /* append next pathname component to output */
1454 memcpy(xp, tp, len);
1455 xp += len;
1456 *xp = '\0';
1457
1458 /* lstat the current output, see if it's a symlink */
1459 if (mksh_lstat(Xstring(xs, xp), &sb)) {
1460 /* lstat failed */
1461 if (errno == ENOENT) {
1462 /* because the pathname does not exist */
1463 while (*ip == '/')
1464 /* skip any trailing slashes */
1465 ++ip;
1466 /* no more components left? */
1467 if (!*ip)
1468 /* we can still return successfully */
1469 break;
1470 /* more components left? fall through */
1471 }
1472 /* not ENOENT or not at the end of ipath */
1473 goto notfound;
1474 }
1475
1476 /* check if we encountered a symlink? */
1477 if (S_ISLNK(sb.st_mode)) {
1478 #ifndef MKSH__NO_SYMLINK
1479 /* reached maximum recursion depth? */
1480 if (!symlinks--) {
1481 /* yep, prevent infinite loops */
1482 errno = ELOOP;
1483 goto notfound;
1484 }
1485
1486 /* get symlink(7) target */
1487 if (pathcnd) {
1488 #ifdef MKSH__NO_PATH_MAX
1489 if (notoktoadd(pathlen, 1)) {
1490 errno = ENAMETOOLONG;
1491 goto notfound;
1492 }
1493 #endif
1494 ldest = aresize(ldest, pathlen + 1, ATEMP);
1495 }
1496 llen = readlink(Xstring(xs, xp), ldest, pathlen);
1497 if (llen < 0)
1498 /* oops... */
1499 goto notfound;
1500 ldest[llen] = '\0';
1501
1502 /*
1503 * restart if symlink target is an absolute path,
1504 * otherwise continue with currently resolved prefix
1505 */
1506 /* append rest of current input path to link target */
1507 tp = shf_smprintf("%s%s%s", ldest, *ip ? "/" : "", ip);
1508 afree(ipath, ATEMP);
1509 ip = ipath = tp;
1510 if (ldest[0] != '/') {
1511 /* symlink target is a relative path */
1512 xp = Xrestpos(xs, xp, pos);
1513 } else
1514 #endif
1515 {
1516 /* symlink target is an absolute path */
1517 xp = Xstring(xs, xp);
1518 beginning_of_a_pathname:
1519 /* assert: (ip == ipath)[0] == '/' */
1520 /* assert: xp == xs.beg => start of path */
1521
1522 /* exactly two leading slashes? (SUSv4 3.266) */
1523 if (ip[1] == '/' && ip[2] != '/') {
1524 /* keep them, e.g. for UNC pathnames */
1525 Xput(xs, xp, '/');
1526 }
1527 }
1528 }
1529 /* otherwise (no symlink) merely go on */
1530 }
1531
1532 /*
1533 * either found the target and successfully resolved it,
1534 * or found its parent directory and may create it
1535 */
1536 if (Xlength(xs, xp) == 0)
1537 /*
1538 * if the resolved pathname is "", make it "/",
1539 * otherwise do not add a trailing slash
1540 */
1541 Xput(xs, xp, '/');
1542 Xput(xs, xp, '\0');
1543
1544 /*
1545 * if source path had a trailing slash, check if target path
1546 * is not a non-directory existing file
1547 */
1548 if (ip > ipath && ip[-1] == '/') {
1549 if (stat(Xstring(xs, xp), &sb)) {
1550 if (errno != ENOENT)
1551 goto notfound;
1552 } else if (!S_ISDIR(sb.st_mode)) {
1553 errno = ENOTDIR;
1554 goto notfound;
1555 }
1556 /* target now either does not exist or is a directory */
1557 }
1558
1559 /* return target path */
1560 if (ldest != NULL)
1561 afree(ldest, ATEMP);
1562 afree(ipath, ATEMP);
1563 return (Xclose(xs, xp));
1564
1565 notfound:
1566 /* save; freeing memory might trash it */
1567 llen = errno;
1568 if (ldest != NULL)
1569 afree(ldest, ATEMP);
1570 afree(ipath, ATEMP);
1571 Xfree(xs, xp);
1572 errno = llen;
1573 return (NULL);
1574
1575 #undef pathlen
1576 #undef pathcnd
1577 }
1578
1579 /**
1580 * Makes a filename into result using the following algorithm.
1581 * - make result NULL
1582 * - if file starts with '/', append file to result & set cdpathp to NULL
1583 * - if file starts with ./ or ../ append cwd and file to result
1584 * and set cdpathp to NULL
1585 * - if the first element of cdpathp doesnt start with a '/' xx or '.' xx
1586 * then cwd is appended to result.
1587 * - the first element of cdpathp is appended to result
1588 * - file is appended to result
1589 * - cdpathp is set to the start of the next element in cdpathp (or NULL
1590 * if there are no more elements.
1591 * The return value indicates whether a non-null element from cdpathp
1592 * was appended to result.
1593 */
1594 static int
make_path(const char * cwd,const char * file,char ** cdpathp,XString * xsp,int * phys_pathp)1595 make_path(const char *cwd, const char *file,
1596 /* pointer to colon-separated list */
1597 char **cdpathp,
1598 XString *xsp,
1599 int *phys_pathp)
1600 {
1601 int rval = 0;
1602 bool use_cdpath = true;
1603 char *plist;
1604 size_t len, plen = 0;
1605 char *xp = Xstring(*xsp, xp);
1606
1607 if (!file)
1608 file = null;
1609
1610 if (file[0] == '/') {
1611 *phys_pathp = 0;
1612 use_cdpath = false;
1613 } else {
1614 if (file[0] == '.') {
1615 char c = file[1];
1616
1617 if (c == '.')
1618 c = file[2];
1619 if (c == '/' || c == '\0')
1620 use_cdpath = false;
1621 }
1622
1623 plist = *cdpathp;
1624 if (!plist)
1625 use_cdpath = false;
1626 else if (use_cdpath) {
1627 char *pend;
1628
1629 for (pend = plist; *pend && *pend != ':'; pend++)
1630 ;
1631 plen = pend - plist;
1632 *cdpathp = *pend ? pend + 1 : NULL;
1633 }
1634
1635 if ((!use_cdpath || !plen || plist[0] != '/') &&
1636 (cwd && *cwd)) {
1637 len = strlen(cwd);
1638 XcheckN(*xsp, xp, len);
1639 memcpy(xp, cwd, len);
1640 xp += len;
1641 if (cwd[len - 1] != '/')
1642 Xput(*xsp, xp, '/');
1643 }
1644 *phys_pathp = Xlength(*xsp, xp);
1645 if (use_cdpath && plen) {
1646 XcheckN(*xsp, xp, plen);
1647 memcpy(xp, plist, plen);
1648 xp += plen;
1649 if (plist[plen - 1] != '/')
1650 Xput(*xsp, xp, '/');
1651 rval = 1;
1652 }
1653 }
1654
1655 len = strlen(file) + 1;
1656 XcheckN(*xsp, xp, len);
1657 memcpy(xp, file, len);
1658
1659 if (!use_cdpath)
1660 *cdpathp = NULL;
1661
1662 return (rval);
1663 }
1664
1665 /*-
1666 * Simplify pathnames containing "." and ".." entries.
1667 *
1668 * simplify_path(this) = that
1669 * /a/b/c/./../d/.. /a/b
1670 * //./C/foo/bar/../baz //C/foo/baz
1671 * /foo/ /foo
1672 * /foo/../../bar /bar
1673 * /foo/./blah/.. /foo
1674 * . .
1675 * .. ..
1676 * ./foo foo
1677 * foo/../../../bar ../../bar
1678 */
1679 void
simplify_path(char * p)1680 simplify_path(char *p)
1681 {
1682 char *dp, *ip, *sp, *tp;
1683 size_t len;
1684 bool needslash;
1685
1686 switch (*p) {
1687 case 0:
1688 return;
1689 case '/':
1690 /* exactly two leading slashes? (SUSv4 3.266) */
1691 if (p[1] == '/' && p[2] != '/')
1692 /* keep them, e.g. for UNC pathnames */
1693 ++p;
1694 needslash = true;
1695 break;
1696 default:
1697 needslash = false;
1698 }
1699 dp = ip = sp = p;
1700
1701 while (*ip) {
1702 /* skip slashes in input */
1703 while (*ip == '/')
1704 ++ip;
1705 if (!*ip)
1706 break;
1707
1708 /* get next pathname component from input */
1709 tp = ip;
1710 while (*ip && *ip != '/')
1711 ++ip;
1712 len = ip - tp;
1713
1714 /* check input for "." and ".." */
1715 if (tp[0] == '.') {
1716 if (len == 1)
1717 /* just continue with the next one */
1718 continue;
1719 else if (len == 2 && tp[1] == '.') {
1720 /* parent level, but how? */
1721 if (*p == '/')
1722 /* absolute path, only one way */
1723 goto strip_last_component;
1724 else if (dp > sp) {
1725 /* relative path, with subpaths */
1726 needslash = false;
1727 strip_last_component:
1728 /* strip off last pathname component */
1729 while (dp > sp)
1730 if (*--dp == '/')
1731 break;
1732 } else {
1733 /* relative path, at its beginning */
1734 if (needslash)
1735 /* or already dotdot-slash'd */
1736 *dp++ = '/';
1737 /* keep dotdot-slash if not absolute */
1738 *dp++ = '.';
1739 *dp++ = '.';
1740 needslash = true;
1741 sp = dp;
1742 }
1743 /* then continue with the next one */
1744 continue;
1745 }
1746 }
1747
1748 if (needslash)
1749 *dp++ = '/';
1750
1751 /* append next pathname component to output */
1752 memmove(dp, tp, len);
1753 dp += len;
1754
1755 /* append slash if we continue */
1756 needslash = true;
1757 /* try next component */
1758 }
1759 if (dp == p)
1760 /* empty path -> dot */
1761 *dp++ = needslash ? '/' : '.';
1762 *dp = '\0';
1763 }
1764
1765 void
set_current_wd(const char * nwd)1766 set_current_wd(const char *nwd)
1767 {
1768 char *allocd = NULL;
1769
1770 if (nwd == NULL) {
1771 allocd = ksh_get_wd();
1772 nwd = allocd ? allocd : null;
1773 }
1774
1775 afree(current_wd, APERM);
1776 strdupx(current_wd, nwd, APERM);
1777
1778 afree(allocd, ATEMP);
1779 }
1780
1781 int
c_cd(const char ** wp)1782 c_cd(const char **wp)
1783 {
1784 int optc, rv, phys_path;
1785 bool physical = tobool(Flag(FPHYSICAL));
1786 /* was a node from cdpath added in? */
1787 int cdnode;
1788 /* show where we went?, error for $PWD */
1789 bool printpath = false, eflag = false;
1790 struct tbl *pwd_s, *oldpwd_s;
1791 XString xs;
1792 char *dir, *allocd = NULL, *tryp, *pwd, *cdpath;
1793
1794 while ((optc = ksh_getopt(wp, &builtin_opt, "eLP")) != -1)
1795 switch (optc) {
1796 case 'e':
1797 eflag = true;
1798 break;
1799 case 'L':
1800 physical = false;
1801 break;
1802 case 'P':
1803 physical = true;
1804 break;
1805 case '?':
1806 return (2);
1807 }
1808 wp += builtin_opt.optind;
1809
1810 if (Flag(FRESTRICTED)) {
1811 bi_errorf("restricted shell - can't cd");
1812 return (2);
1813 }
1814
1815 pwd_s = global("PWD");
1816 oldpwd_s = global("OLDPWD");
1817
1818 if (!wp[0]) {
1819 /* No arguments - go home */
1820 if ((dir = str_val(global("HOME"))) == null) {
1821 bi_errorf("no home directory (HOME not set)");
1822 return (2);
1823 }
1824 } else if (!wp[1]) {
1825 /* One argument: - or dir */
1826 strdupx(allocd, wp[0], ATEMP);
1827 if (ksh_isdash((dir = allocd))) {
1828 afree(allocd, ATEMP);
1829 allocd = NULL;
1830 dir = str_val(oldpwd_s);
1831 if (dir == null) {
1832 bi_errorf("no OLDPWD");
1833 return (2);
1834 }
1835 printpath = true;
1836 }
1837 } else if (!wp[2]) {
1838 /* Two arguments - substitute arg1 in PWD for arg2 */
1839 size_t ilen, olen, nlen, elen;
1840 char *cp;
1841
1842 if (!current_wd[0]) {
1843 bi_errorf("can't determine current directory");
1844 return (2);
1845 }
1846 /*
1847 * substitute arg1 for arg2 in current path.
1848 * if the first substitution fails because the cd fails
1849 * we could try to find another substitution. For now
1850 * we don't
1851 */
1852 if ((cp = strstr(current_wd, wp[0])) == NULL) {
1853 bi_errorf("bad substitution");
1854 return (2);
1855 }
1856 /*-
1857 * ilen = part of current_wd before wp[0]
1858 * elen = part of current_wd after wp[0]
1859 * because current_wd and wp[1] need to be in memory at the
1860 * same time beforehand the addition can stay unchecked
1861 */
1862 ilen = cp - current_wd;
1863 olen = strlen(wp[0]);
1864 nlen = strlen(wp[1]);
1865 elen = strlen(current_wd + ilen + olen) + 1;
1866 dir = allocd = alloc(ilen + nlen + elen, ATEMP);
1867 memcpy(dir, current_wd, ilen);
1868 memcpy(dir + ilen, wp[1], nlen);
1869 memcpy(dir + ilen + nlen, current_wd + ilen + olen, elen);
1870 printpath = true;
1871 } else {
1872 bi_errorf("too many arguments");
1873 return (2);
1874 }
1875
1876 #ifdef MKSH__NO_PATH_MAX
1877 /* only a first guess; make_path will enlarge xs if necessary */
1878 XinitN(xs, 1024, ATEMP);
1879 #else
1880 XinitN(xs, PATH_MAX, ATEMP);
1881 #endif
1882
1883 cdpath = str_val(global("CDPATH"));
1884 do {
1885 cdnode = make_path(current_wd, dir, &cdpath, &xs, &phys_path);
1886 if (physical)
1887 rv = chdir(tryp = Xstring(xs, xp) + phys_path);
1888 else {
1889 simplify_path(Xstring(xs, xp));
1890 rv = chdir(tryp = Xstring(xs, xp));
1891 }
1892 } while (rv < 0 && cdpath != NULL);
1893
1894 if (rv < 0) {
1895 if (cdnode)
1896 bi_errorf("%s: %s", dir, "bad directory");
1897 else
1898 bi_errorf("%s: %s", tryp, cstrerror(errno));
1899 afree(allocd, ATEMP);
1900 Xfree(xs, xp);
1901 return (2);
1902 }
1903
1904 rv = 0;
1905
1906 /* allocd (above) => dir, which is no longer used */
1907 afree(allocd, ATEMP);
1908 allocd = NULL;
1909
1910 /* Clear out tracked aliases with relative paths */
1911 flushcom(false);
1912
1913 /*
1914 * Set OLDPWD (note: unsetting OLDPWD does not disable this
1915 * setting in AT&T ksh)
1916 */
1917 if (current_wd[0])
1918 /* Ignore failure (happens if readonly or integer) */
1919 setstr(oldpwd_s, current_wd, KSH_RETURN_ERROR);
1920
1921 if (Xstring(xs, xp)[0] != '/') {
1922 pwd = NULL;
1923 } else if (!physical) {
1924 goto norealpath_PWD;
1925 } else if ((pwd = allocd = do_realpath(Xstring(xs, xp))) == NULL) {
1926 if (eflag)
1927 rv = 1;
1928 norealpath_PWD:
1929 pwd = Xstring(xs, xp);
1930 }
1931
1932 /* Set PWD */
1933 if (pwd) {
1934 char *ptmp = pwd;
1935
1936 set_current_wd(ptmp);
1937 /* Ignore failure (happens if readonly or integer) */
1938 setstr(pwd_s, ptmp, KSH_RETURN_ERROR);
1939 } else {
1940 set_current_wd(null);
1941 pwd = Xstring(xs, xp);
1942 /* XXX unset $PWD? */
1943 if (eflag)
1944 rv = 1;
1945 }
1946 if (printpath || cdnode)
1947 shprintf("%s\n", pwd);
1948
1949 afree(allocd, ATEMP);
1950 Xfree(xs, xp);
1951 return (rv);
1952 }
1953
1954
1955 #ifdef KSH_CHVT_CODE
1956 extern void chvt_reinit(void);
1957
1958 static void
chvt(const Getopt * go)1959 chvt(const Getopt *go)
1960 {
1961 const char *dv = go->optarg;
1962 char *cp = NULL;
1963 int fd;
1964
1965 switch (*dv) {
1966 case '-':
1967 dv = "/dev/null";
1968 break;
1969 case '!':
1970 ++dv;
1971 /* FALLTHROUGH */
1972 default: {
1973 struct stat sb;
1974
1975 if (stat(dv, &sb)) {
1976 cp = shf_smprintf("/dev/ttyC%s", dv);
1977 dv = cp;
1978 if (stat(dv, &sb)) {
1979 memmove(cp + 1, cp, /* /dev/tty */ 8);
1980 dv = cp + 1;
1981 if (stat(dv, &sb)) {
1982 errorf("%s: %s: %s", "chvt",
1983 "can't find tty", go->optarg);
1984 }
1985 }
1986 }
1987 if (!(sb.st_mode & S_IFCHR))
1988 errorf("%s: %s: %s", "chvt", "not a char device", dv);
1989 #ifndef MKSH_DISABLE_REVOKE_WARNING
1990 #if HAVE_REVOKE
1991 if (revoke(dv))
1992 #endif
1993 warningf(false, "%s: %s %s", "chvt",
1994 "new shell is potentially insecure, can't revoke",
1995 dv);
1996 #endif
1997 }
1998 }
1999 if ((fd = open(dv, O_RDWR | O_BINARY)) < 0) {
2000 sleep(1);
2001 if ((fd = open(dv, O_RDWR | O_BINARY)) < 0) {
2002 errorf("%s: %s %s", "chvt", "can't open", dv);
2003 }
2004 }
2005 if (go->optarg[0] != '!') {
2006 switch (fork()) {
2007 case -1:
2008 errorf("%s: %s %s", "chvt", "fork", "failed");
2009 case 0:
2010 break;
2011 default:
2012 exit(0);
2013 }
2014 }
2015 if (setsid() == -1)
2016 errorf("%s: %s %s", "chvt", "setsid", "failed");
2017 if (go->optarg[0] != '-') {
2018 if (ioctl(fd, TIOCSCTTY, NULL) == -1)
2019 errorf("%s: %s %s", "chvt", "TIOCSCTTY", "failed");
2020 if (tcflush(fd, TCIOFLUSH))
2021 errorf("%s: %s %s", "chvt", "TCIOFLUSH", "failed");
2022 }
2023 ksh_dup2(fd, 0, false);
2024 ksh_dup2(fd, 1, false);
2025 ksh_dup2(fd, 2, false);
2026 if (fd > 2)
2027 close(fd);
2028 rndset((unsigned long)chvt_rndsetup(go, sizeof(Getopt)));
2029 chvt_reinit();
2030 }
2031 #endif
2032
2033 #ifdef DEBUG
2034 char *
strchr(char * p,int ch)2035 strchr(char *p, int ch)
2036 {
2037 for (;; ++p) {
2038 if (*p == ch)
2039 return (p);
2040 if (!*p)
2041 return (NULL);
2042 }
2043 /* NOTREACHED */
2044 }
2045
2046 char *
strstr(char * b,const char * l)2047 strstr(char *b, const char *l)
2048 {
2049 char first, c;
2050 size_t n;
2051
2052 if ((first = *l++) == '\0')
2053 return (b);
2054 n = strlen(l);
2055 strstr_look:
2056 while ((c = *b++) != first)
2057 if (c == '\0')
2058 return (NULL);
2059 if (strncmp(b, l, n))
2060 goto strstr_look;
2061 return (b - 1);
2062 }
2063 #endif
2064
2065 #if defined(MKSH_SMALL) && !defined(MKSH_SMALL_BUT_FAST)
2066 char *
strndup_i(const char * src,size_t len,Area * ap)2067 strndup_i(const char *src, size_t len, Area *ap)
2068 {
2069 char *dst = NULL;
2070
2071 if (src != NULL) {
2072 dst = alloc(len + 1, ap);
2073 memcpy(dst, src, len);
2074 dst[len] = '\0';
2075 }
2076 return (dst);
2077 }
2078
2079 char *
strdup_i(const char * src,Area * ap)2080 strdup_i(const char *src, Area *ap)
2081 {
2082 return (src == NULL ? NULL : strndup_i(src, strlen(src), ap));
2083 }
2084 #endif
2085
2086 #if !HAVE_GETRUSAGE
2087 #define INVTCK(r,t) do { \
2088 r.tv_usec = ((t) % (1000000 / CLK_TCK)) * (1000000 / CLK_TCK); \
2089 r.tv_sec = (t) / CLK_TCK; \
2090 } while (/* CONSTCOND */ 0)
2091
2092 int
getrusage(int what,struct rusage * ru)2093 getrusage(int what, struct rusage *ru)
2094 {
2095 struct tms tms;
2096 clock_t u, s;
2097
2098 if (/* ru == NULL || */ times(&tms) == (clock_t)-1)
2099 return (-1);
2100
2101 switch (what) {
2102 case RUSAGE_SELF:
2103 u = tms.tms_utime;
2104 s = tms.tms_stime;
2105 break;
2106 case RUSAGE_CHILDREN:
2107 u = tms.tms_cutime;
2108 s = tms.tms_cstime;
2109 break;
2110 default:
2111 errno = EINVAL;
2112 return (-1);
2113 }
2114 INVTCK(ru->ru_utime, u);
2115 INVTCK(ru->ru_stime, s);
2116 return (0);
2117 }
2118 #endif
2119
2120 /*
2121 * process the string available via fg (get a char)
2122 * and fp (put back a char) for backslash escapes,
2123 * assuming the first call to *fg gets the char di-
2124 * rectly after the backslash; return the character
2125 * (0..0xFF), Unicode (wc + 0x100), or -1 if no known
2126 * escape sequence was found
2127 */
2128 int
unbksl(bool cstyle,int (* fg)(void),void (* fp)(int))2129 unbksl(bool cstyle, int (*fg)(void), void (*fp)(int))
2130 {
2131 int wc, i, c, fc;
2132
2133 fc = (*fg)();
2134 switch (fc) {
2135 case 'a':
2136 /*
2137 * according to the comments in pdksh, \007 seems
2138 * to be more portable than \a (due to HP-UX cc,
2139 * Ultrix cc, old pcc, etc.) so we avoid the escape
2140 * sequence altogether in mksh and assume ASCII
2141 */
2142 wc = 7;
2143 break;
2144 case 'b':
2145 wc = '\b';
2146 break;
2147 case 'c':
2148 if (!cstyle)
2149 goto unknown_escape;
2150 c = (*fg)();
2151 wc = CTRL(c);
2152 break;
2153 case 'E':
2154 case 'e':
2155 wc = 033;
2156 break;
2157 case 'f':
2158 wc = '\f';
2159 break;
2160 case 'n':
2161 wc = '\n';
2162 break;
2163 case 'r':
2164 wc = '\r';
2165 break;
2166 case 't':
2167 wc = '\t';
2168 break;
2169 case 'v':
2170 /* assume ASCII here as well */
2171 wc = 11;
2172 break;
2173 case '1':
2174 case '2':
2175 case '3':
2176 case '4':
2177 case '5':
2178 case '6':
2179 case '7':
2180 if (!cstyle)
2181 goto unknown_escape;
2182 /* FALLTHROUGH */
2183 case '0':
2184 if (cstyle)
2185 (*fp)(fc);
2186 /*
2187 * look for an octal number with up to three
2188 * digits, not counting the leading zero;
2189 * convert it to a raw octet
2190 */
2191 wc = 0;
2192 i = 3;
2193 while (i--)
2194 if ((c = (*fg)()) >= '0' && c <= '7')
2195 wc = (wc << 3) + (c - '0');
2196 else {
2197 (*fp)(c);
2198 break;
2199 }
2200 break;
2201 case 'U':
2202 i = 8;
2203 if (/* CONSTCOND */ 0)
2204 /* FALLTHROUGH */
2205 case 'u':
2206 i = 4;
2207 if (/* CONSTCOND */ 0)
2208 /* FALLTHROUGH */
2209 case 'x':
2210 i = cstyle ? -1 : 2;
2211 /**
2212 * x: look for a hexadecimal number with up to
2213 * two (C style: arbitrary) digits; convert
2214 * to raw octet (C style: Unicode if >0xFF)
2215 * u/U: look for a hexadecimal number with up to
2216 * four (U: eight) digits; convert to Unicode
2217 */
2218 wc = 0;
2219 while (i--) {
2220 wc <<= 4;
2221 if ((c = (*fg)()) >= '0' && c <= '9')
2222 wc += c - '0';
2223 else if (c >= 'A' && c <= 'F')
2224 wc += c - 'A' + 10;
2225 else if (c >= 'a' && c <= 'f')
2226 wc += c - 'a' + 10;
2227 else {
2228 wc >>= 4;
2229 (*fp)(c);
2230 break;
2231 }
2232 }
2233 if ((cstyle && wc > 0xFF) || fc != 'x')
2234 /* Unicode marker */
2235 wc += 0x100;
2236 break;
2237 case '\'':
2238 if (!cstyle)
2239 goto unknown_escape;
2240 wc = '\'';
2241 break;
2242 case '\\':
2243 wc = '\\';
2244 break;
2245 default:
2246 unknown_escape:
2247 (*fp)(fc);
2248 return (-1);
2249 }
2250
2251 return (wc);
2252 }
2253