1 /*	$OpenBSD: misc.c,v 1.41 2015/09/10 22:48:58 nicm Exp $	*/
2 /*	$OpenBSD: path.c,v 1.13 2015/09/05 09:47:08 jsg Exp $	*/
3 
4 /*-
5  * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
6  *		 2011, 2012, 2013, 2014, 2015, 2016
7  *	mirabilos <m@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 1.249 2016/11/11 23:31:35 tg Exp $");
34 
35 #define KSH_CHVT_FLAG
36 #ifdef MKSH_SMALL
37 #undef KSH_CHVT_FLAG
38 #endif
39 #ifdef TIOCSCTTY
40 #define KSH_CHVT_CODE
41 #define KSH_CHVT_FLAG
42 #endif
43 #ifdef MKSH_LEGACY_MODE
44 #undef KSH_CHVT_CODE
45 #undef KSH_CHVT_FLAG
46 #endif
47 
48 /* type bits for unsigned char */
49 unsigned char chtypes[UCHAR_MAX + 1];
50 
51 static const unsigned char *pat_scan(const unsigned char *,
52     const unsigned char *, bool) MKSH_A_PURE;
53 static int do_gmatch(const unsigned char *, const unsigned char *,
54     const unsigned char *, const unsigned char *) MKSH_A_PURE;
55 static const unsigned char *gmatch_cclass(const unsigned char *, unsigned char)
56     MKSH_A_PURE;
57 #ifdef KSH_CHVT_CODE
58 static void chvt(const Getopt *);
59 #endif
60 
61 /*XXX this should go away */
62 static int make_path(const char *, const char *, char **, XString *, int *);
63 
64 #ifdef SETUID_CAN_FAIL_WITH_EAGAIN
65 /* we don't need to check for other codes, EPERM won't happen */
66 #define DO_SETUID(func, argvec) do {					\
67 	if ((func argvec) && errno == EAGAIN)				\
68 		errorf("%s failed with EAGAIN, probably due to a"	\
69 		    " too low process limit; aborting", #func);		\
70 } while (/* CONSTCOND */ 0)
71 #else
72 #define DO_SETUID(func, argvec) func argvec
73 #endif
74 
75 /*
76  * Fast character classes
77  */
78 void
setctypes(const char * s,int t)79 setctypes(const char *s, int t)
80 {
81 	if (t & C_IFS) {
82 		unsigned int i = 0;
83 
84 		while (++i <= UCHAR_MAX)
85 			chtypes[i] &= ~C_IFS;
86 		/* include '\0' in C_IFS */
87 		chtypes[0] |= C_IFS;
88 	}
89 	while (*s != 0)
90 		chtypes[(unsigned char)*s++] |= t;
91 }
92 
93 void
initctypes(void)94 initctypes(void)
95 {
96 	setctypes(letters_uc, C_ALPHA);
97 	setctypes(letters_lc, C_ALPHA);
98 	chtypes['_'] |= C_ALPHA;
99 	setctypes("0123456789", C_DIGIT);
100 	/* \0 added automatically */
101 	setctypes(TC_LEX1, C_LEX1);
102 	setctypes("*@#!$-?", C_VAR1);
103 	setctypes(TC_IFSWS, C_IFSWS);
104 	setctypes("=-+?", C_SUBOP1);
105 	setctypes("\t\n \"#$&'()*;<=>?[\\]`|", C_QUOTE);
106 }
107 
108 /* called from XcheckN() to grow buffer */
109 char *
Xcheck_grow(XString * xsp,const char * xp,size_t more)110 Xcheck_grow(XString *xsp, const char *xp, size_t more)
111 {
112 	const char *old_beg = xsp->beg;
113 
114 	if (more < xsp->len)
115 		more = xsp->len;
116 	/* (xsp->len + X_EXTRA) never overflows */
117 	checkoktoadd(more, xsp->len + X_EXTRA);
118 	xsp->beg = aresize(xsp->beg, (xsp->len += more) + X_EXTRA, xsp->areap);
119 	xsp->end = xsp->beg + xsp->len;
120 	return (xsp->beg + (xp - old_beg));
121 }
122 
123 
124 #define SHFLAGS_DEFNS
125 #define FN(sname,cname,flags,ochar)		\
126 	static const struct {			\
127 		/* character flag (if any) */	\
128 		char c;				\
129 		/* OF_* */			\
130 		unsigned char optflags;		\
131 		/* long name of option */	\
132 		char name[sizeof(sname)];	\
133 	} shoptione_ ## cname = {		\
134 		ochar, flags, sname		\
135 	};
136 #include "sh_flags.gen"
137 
138 #define OFC(i) (options[i][-2])
139 #define OFF(i) (((const unsigned char *)options[i])[-1])
140 #define OFN(i) (options[i])
141 
142 const char * const options[] = {
143 #define SHFLAGS_ITEMS
144 #include "sh_flags.gen"
145 };
146 
147 /*
148  * translate -o option into F* constant (also used for test -o option)
149  */
150 size_t
option(const char * n)151 option(const char *n)
152 {
153 	size_t i = 0;
154 
155 	if ((n[0] == '-' || n[0] == '+') && n[1] && !n[2])
156 		while (i < NELEM(options)) {
157 			if (OFC(i) == n[1])
158 				return (i);
159 			++i;
160 		}
161 	else
162 		while (i < NELEM(options)) {
163 			if (!strcmp(OFN(i), n))
164 				return (i);
165 			++i;
166 		}
167 
168 	return ((size_t)-1);
169 }
170 
171 struct options_info {
172 	int opt_width;
173 	int opts[NELEM(options)];
174 };
175 
176 static void options_fmt_entry(char *, size_t, unsigned int, const void *);
177 static void printoptions(bool);
178 
179 /* format a single select menu item */
180 static void
options_fmt_entry(char * buf,size_t buflen,unsigned int i,const void * arg)181 options_fmt_entry(char *buf, size_t buflen, unsigned int i, const void *arg)
182 {
183 	const struct options_info *oi = (const struct options_info *)arg;
184 
185 	shf_snprintf(buf, buflen, "%-*s %s",
186 	    oi->opt_width, OFN(oi->opts[i]),
187 	    Flag(oi->opts[i]) ? "on" : "off");
188 }
189 
190 static void
printoptions(bool verbose)191 printoptions(bool verbose)
192 {
193 	size_t i = 0;
194 
195 	if (verbose) {
196 		size_t n = 0, len, octs = 0;
197 		struct options_info oi;
198 		struct columnise_opts co;
199 
200 		/* verbose version */
201 		shf_puts("Current option settings\n", shl_stdout);
202 
203 		oi.opt_width = 0;
204 		while (i < NELEM(options)) {
205 			if ((len = strlen(OFN(i)))) {
206 				oi.opts[n++] = i;
207 				if (len > octs)
208 					octs = len;
209 				len = utf_mbswidth(OFN(i));
210 				if ((int)len > oi.opt_width)
211 					oi.opt_width = (int)len;
212 			}
213 			++i;
214 		}
215 		co.shf = shl_stdout;
216 		co.linesep = '\n';
217 		co.prefcol = co.do_last = true;
218 		print_columns(&co, n, options_fmt_entry, &oi,
219 		    octs + 4, oi.opt_width + 4);
220 	} else {
221 		/* short version like AT&T ksh93 */
222 		shf_puts(Tset, shl_stdout);
223 		while (i < NELEM(options)) {
224 			if (Flag(i) && OFN(i)[0])
225 				shprintf(" -o %s", OFN(i));
226 			++i;
227 		}
228 		shf_putc('\n', shl_stdout);
229 	}
230 }
231 
232 char *
getoptions(void)233 getoptions(void)
234 {
235 	size_t i = 0;
236 	char c, m[(int)FNFLAGS + 1];
237 	char *cp = m;
238 
239 	while (i < NELEM(options)) {
240 		if ((c = OFC(i)) && Flag(i))
241 			*cp++ = c;
242 		++i;
243 	}
244 	strndupx(cp, m, cp - m, ATEMP);
245 	return (cp);
246 }
247 
248 /* change a Flag(*) value; takes care of special actions */
249 void
change_flag(enum sh_flag f,int what,bool newset)250 change_flag(enum sh_flag f, int what, bool newset)
251 {
252 	unsigned char oldval;
253 	unsigned char newval = (newset ? 1 : 0);
254 
255 	if (f == FXTRACE) {
256 		change_xtrace(newval, true);
257 		return;
258 	}
259 	oldval = Flag(f);
260 	Flag(f) = newval = (newset ? 1 : 0);
261 #ifndef MKSH_UNEMPLOYED
262 	if (f == FMONITOR) {
263 		if (what != OF_CMDLINE && newval != oldval)
264 			j_change();
265 	} else
266 #endif
267 #ifndef MKSH_NO_CMDLINE_EDITING
268 	  if ((
269 #if !MKSH_S_NOVI
270 	    f == FVI ||
271 #endif
272 	    f == FEMACS || f == FGMACS) && newval) {
273 #if !MKSH_S_NOVI
274 		Flag(FVI) =
275 #endif
276 		    Flag(FEMACS) = Flag(FGMACS) = 0;
277 		Flag(f) = newval;
278 	} else
279 #endif
280 	  if (f == FPRIVILEGED && oldval && !newval) {
281 		/* Turning off -p? */
282 
283 		/*XXX this can probably be optimised */
284 		kshegid = kshgid = getgid();
285 		ksheuid = kshuid = getuid();
286 #if HAVE_SETRESUGID
287 		DO_SETUID(setresgid, (kshegid, kshegid, kshegid));
288 #if HAVE_SETGROUPS
289 		/* setgroups doesn't EAGAIN on Linux */
290 		setgroups(1, &kshegid);
291 #endif
292 		DO_SETUID(setresuid, (ksheuid, ksheuid, ksheuid));
293 #else /* !HAVE_SETRESUGID */
294 		/* setgid, setegid, seteuid don't EAGAIN on Linux */
295 		setgid(kshegid);
296 #ifndef MKSH__NO_SETEUGID
297 		setegid(kshegid);
298 #endif
299 		DO_SETUID(setuid, (ksheuid));
300 #ifndef MKSH__NO_SETEUGID
301 		seteuid(ksheuid);
302 #endif
303 #endif /* !HAVE_SETRESUGID */
304 	} else if ((f == FPOSIX || f == FSH) && newval) {
305 		/* Turning on -o posix or -o sh? */
306 		Flag(FBRACEEXPAND) = 0;
307 	} else if (f == FTALKING) {
308 		/* Changing interactive flag? */
309 		if ((what == OF_CMDLINE || what == OF_SET) && procpid == kshpid)
310 			Flag(FTALKING_I) = newval;
311 	}
312 }
313 
314 void
change_xtrace(unsigned char newval,bool dosnapshot)315 change_xtrace(unsigned char newval, bool dosnapshot)
316 {
317 	static bool in_xtrace;
318 
319 	if (in_xtrace)
320 		return;
321 
322 	if (!dosnapshot && newval == Flag(FXTRACE))
323 		return;
324 
325 	if (Flag(FXTRACE) == 2) {
326 		shf_putc('\n', shl_xtrace);
327 		Flag(FXTRACE) = 1;
328 		shf_flush(shl_xtrace);
329 	}
330 
331 	if (!dosnapshot && Flag(FXTRACE) == 1)
332 		switch (newval) {
333 		case 1:
334 			return;
335 		case 2:
336 			goto changed_xtrace;
337 		}
338 
339 	shf_flush(shl_xtrace);
340 	if (shl_xtrace->fd != 2)
341 		close(shl_xtrace->fd);
342 	if (!newval || (shl_xtrace->fd = savefd(2)) == -1)
343 		shl_xtrace->fd = 2;
344 
345  changed_xtrace:
346 	if ((Flag(FXTRACE) = newval) == 2) {
347 		in_xtrace = true;
348 		Flag(FXTRACE) = 0;
349 		shf_puts(substitute(str_val(global("PS4")), 0), shl_xtrace);
350 		Flag(FXTRACE) = 2;
351 		in_xtrace = false;
352 	}
353 }
354 
355 /*
356  * Parse command line and set command arguments. Returns the index of
357  * non-option arguments, -1 if there is an error.
358  */
359 int
parse_args(const char ** argv,int what,bool * setargsp)360 parse_args(const char **argv,
361     /* OF_FIRSTTIME, OF_CMDLINE, or OF_SET */
362     int what,
363     bool *setargsp)
364 {
365 	static const char cmd_opts[] =
366 #define SHFLAGS_NOT_SET
367 #define SHFLAGS_OPTCS
368 #include "sh_flags.gen"
369 #undef SHFLAGS_NOT_SET
370 	    ;
371 	static const char set_opts[] =
372 #define SHFLAGS_NOT_CMD
373 #define SHFLAGS_OPTCS
374 #include "sh_flags.gen"
375 #undef SHFLAGS_NOT_CMD
376 	    ;
377 	bool set;
378 	const char *opts;
379 	const char *array = NULL;
380 	Getopt go;
381 	size_t i;
382 	int optc, arrayset = 0;
383 	bool sortargs = false;
384 	bool fcompatseen = false;
385 
386 	if (what == OF_CMDLINE) {
387 		const char *p = argv[0], *q;
388 		/*
389 		 * Set FLOGIN before parsing options so user can clear
390 		 * flag using +l.
391 		 */
392 		if (*p != '-')
393 			for (q = p; *q; )
394 				if (mksh_cdirsep(*q++))
395 					p = q;
396 		Flag(FLOGIN) = (*p == '-');
397 		opts = cmd_opts;
398 	} else if (what == OF_FIRSTTIME) {
399 		opts = cmd_opts;
400 	} else
401 		opts = set_opts;
402 	ksh_getopt_reset(&go, GF_ERROR|GF_PLUSOPT);
403 	while ((optc = ksh_getopt(argv, &go, opts)) != -1) {
404 		set = tobool(!(go.info & GI_PLUS));
405 		switch (optc) {
406 		case 'A':
407 			if (what == OF_FIRSTTIME)
408 				break;
409 			arrayset = set ? 1 : -1;
410 			array = go.optarg;
411 			break;
412 
413 		case 'o':
414 			if (what == OF_FIRSTTIME)
415 				break;
416 			if (go.optarg == NULL) {
417 				/*
418 				 * lone -o: print options
419 				 *
420 				 * Note that on the command line, -o requires
421 				 * an option (ie, can't get here if what is
422 				 * OF_CMDLINE).
423 				 */
424 				printoptions(set);
425 				break;
426 			}
427 			i = option(go.optarg);
428 			if ((i == FPOSIX || i == FSH) && set && !fcompatseen) {
429 				/*
430 				 * If running 'set -o posix' or
431 				 * 'set -o sh', turn off the other;
432 				 * if running 'set -o posix -o sh'
433 				 * allow both to be set though.
434 				 */
435 				Flag(FPOSIX) = 0;
436 				Flag(FSH) = 0;
437 				fcompatseen = true;
438 			}
439 			if ((i != (size_t)-1) && (set ? 1U : 0U) == Flag(i))
440 				/*
441 				 * Don't check the context if the flag
442 				 * isn't changing - makes "set -o interactive"
443 				 * work if you're already interactive. Needed
444 				 * if the output of "set +o" is to be used.
445 				 */
446 				;
447 			else if ((i != (size_t)-1) && (OFF(i) & what))
448 				change_flag((enum sh_flag)i, what, set);
449 			else {
450 				bi_errorf(Tf_sD_s, go.optarg,
451 				    Tunknown_option);
452 				return (-1);
453 			}
454 			break;
455 
456 #ifdef KSH_CHVT_FLAG
457 		case 'T':
458 			if (what != OF_FIRSTTIME)
459 				break;
460 #ifndef KSH_CHVT_CODE
461 			errorf("no TIOCSCTTY ioctl");
462 #else
463 			change_flag(FTALKING, OF_CMDLINE, true);
464 			chvt(&go);
465 			break;
466 #endif
467 #endif
468 
469 		case '?':
470 			return (-1);
471 
472 		default:
473 			if (what == OF_FIRSTTIME)
474 				break;
475 			/* -s: sort positional params (AT&T ksh stupidity) */
476 			if (what == OF_SET && optc == 's') {
477 				sortargs = true;
478 				break;
479 			}
480 			for (i = 0; i < NELEM(options); i++)
481 				if (optc == OFC(i) &&
482 				    (what & OFF(i))) {
483 					change_flag((enum sh_flag)i, what, set);
484 					break;
485 				}
486 			if (i == NELEM(options))
487 				internal_errorf("parse_args: '%c'", optc);
488 		}
489 	}
490 	if (!(go.info & GI_MINUSMINUS) && argv[go.optind] &&
491 	    (argv[go.optind][0] == '-' || argv[go.optind][0] == '+') &&
492 	    argv[go.optind][1] == '\0') {
493 		/* lone - clears -v and -x flags */
494 		if (argv[go.optind][0] == '-') {
495 			Flag(FVERBOSE) = 0;
496 			change_xtrace(0, false);
497 		}
498 		/* set skips lone - or + option */
499 		go.optind++;
500 	}
501 	if (setargsp)
502 		/* -- means set $#/$* even if there are no arguments */
503 		*setargsp = !arrayset && ((go.info & GI_MINUSMINUS) ||
504 		    argv[go.optind]);
505 
506 	if (arrayset) {
507 		const char *ccp = NULL;
508 
509 		if (*array)
510 			ccp = skip_varname(array, false);
511 		if (!ccp || !(!ccp[0] || (ccp[0] == '+' && !ccp[1]))) {
512 			bi_errorf(Tf_sD_s, array, Tnot_ident);
513 			return (-1);
514 		}
515 	}
516 	if (sortargs) {
517 		for (i = go.optind; argv[i]; i++)
518 			;
519 		qsort(&argv[go.optind], i - go.optind, sizeof(void *),
520 		    xstrcmp);
521 	}
522 	if (arrayset)
523 		go.optind += set_array(array, tobool(arrayset > 0),
524 		    argv + go.optind);
525 
526 	return (go.optind);
527 }
528 
529 /* parse a decimal number: returns 0 if string isn't a number, 1 otherwise */
530 int
getn(const char * s,int * ai)531 getn(const char *s, int *ai)
532 {
533 	char c;
534 	mksh_ari_u num;
535 	bool neg = false;
536 
537 	num.u = 0;
538 
539 	do {
540 		c = *s++;
541 	} while (ksh_isspace(c));
542 
543 	switch (c) {
544 	case '-':
545 		neg = true;
546 		/* FALLTHROUGH */
547 	case '+':
548 		c = *s++;
549 		break;
550 	}
551 
552 	do {
553 		if (!ksh_isdigit(c))
554 			/* not numeric */
555 			return (0);
556 		if (num.u > 214748364U)
557 			/* overflow on multiplication */
558 			return (0);
559 		num.u = num.u * 10U + (unsigned int)ksh_numdig(c);
560 		/* now: num.u <= 2147483649U */
561 	} while ((c = *s++));
562 
563 	if (num.u > (neg ? 2147483648U : 2147483647U))
564 		/* overflow for signed 32-bit int */
565 		return (0);
566 
567 	if (neg)
568 		num.u = -num.u;
569 	*ai = num.i;
570 	return (1);
571 }
572 
573 /**
574  * pattern simplifications:
575  * - @(x) -> x (not @(x|y) though)
576  * - ** -> *
577  */
578 static void *
simplify_gmatch_pattern(const unsigned char * sp)579 simplify_gmatch_pattern(const unsigned char *sp)
580 {
581 	uint8_t c;
582 	unsigned char *cp, *dp;
583 	const unsigned char *ps, *se;
584 
585 	cp = alloc(strlen((const void *)sp) + 1, ATEMP);
586 	goto simplify_gmatch_pat1a;
587 
588 	/* foo@(b@(a)r)b@(a|a)z -> foobarb@(a|a)z */
589  simplify_gmatch_pat1:
590 	sp = cp;
591  simplify_gmatch_pat1a:
592 	dp = cp;
593 	se = sp + strlen((const void *)sp);
594 	while ((c = *sp++)) {
595 		if (!ISMAGIC(c)) {
596 			*dp++ = c;
597 			continue;
598 		}
599 		switch ((c = *sp++)) {
600 		case 0x80|'@':
601 		/* simile for @ */
602 		case 0x80|' ':
603 			/* check whether it has only one clause */
604 			ps = pat_scan(sp, se, true);
605 			if (!ps || ps[-1] != /*(*/ ')')
606 				/* nope */
607 				break;
608 			/* copy inner clause until matching close */
609 			ps -= 2;
610 			while ((const unsigned char *)sp < ps)
611 				*dp++ = *sp++;
612 			/* skip MAGIC and closing parenthesis */
613 			sp += 2;
614 			/* copy the rest of the pattern */
615 			memmove(dp, sp, strlen((const void *)sp) + 1);
616 			/* redo from start */
617 			goto simplify_gmatch_pat1;
618 		}
619 		*dp++ = MAGIC;
620 		*dp++ = c;
621 	}
622 	*dp = '\0';
623 
624 	/* collapse adjacent asterisk wildcards */
625 	sp = dp = cp;
626 	while ((c = *sp++)) {
627 		if (!ISMAGIC(c)) {
628 			*dp++ = c;
629 			continue;
630 		}
631 		switch ((c = *sp++)) {
632 		case '*':
633 			while (ISMAGIC(sp[0]) && sp[1] == c)
634 				sp += 2;
635 			break;
636 		}
637 		*dp++ = MAGIC;
638 		*dp++ = c;
639 	}
640 	*dp = '\0';
641 
642 	/* return the result, allocated from ATEMP */
643 	return (cp);
644 }
645 
646 /* -------- gmatch.c -------- */
647 
648 /*
649  * int gmatch(string, pattern)
650  * char *string, *pattern;
651  *
652  * Match a pattern as in sh(1).
653  * pattern character are prefixed with MAGIC by expand.
654  */
655 int
gmatchx(const char * s,const char * p,bool isfile)656 gmatchx(const char *s, const char *p, bool isfile)
657 {
658 	const char *se, *pe;
659 	char *pnew;
660 	int rv;
661 
662 	if (s == NULL || p == NULL)
663 		return (0);
664 
665 	se = s + strlen(s);
666 	pe = p + strlen(p);
667 	/*
668 	 * isfile is false iff no syntax check has been done on
669 	 * the pattern. If check fails, just to a strcmp().
670 	 */
671 	if (!isfile && !has_globbing(p, pe)) {
672 		size_t len = pe - p + 1;
673 		char tbuf[64];
674 		char *t = len <= sizeof(tbuf) ? tbuf : alloc(len, ATEMP);
675 		debunk(t, p, len);
676 		return (!strcmp(t, s));
677 	}
678 
679 	/*
680 	 * since the do_gmatch() engine sucks so much, we must do some
681 	 * pattern simplifications
682 	 */
683 	pnew = simplify_gmatch_pattern((const unsigned char *)p);
684 	pe = pnew + strlen(pnew);
685 
686 	rv = do_gmatch((const unsigned char *)s, (const unsigned char *)se,
687 	    (const unsigned char *)pnew, (const unsigned char *)pe);
688 	afree(pnew, ATEMP);
689 	return (rv);
690 }
691 
692 /**
693  * Returns if p is a syntacticly correct globbing pattern, false
694  * if it contains no pattern characters or if there is a syntax error.
695  * Syntax errors are:
696  *	- [ with no closing ]
697  *	- imbalanced $(...) expression
698  *	- [...] and *(...) not nested (eg, [a$(b|]c), *(a[b|c]d))
699  */
700 /*XXX
701  * - if no magic,
702  *	if dest given, copy to dst
703  *	return ?
704  * - if magic && (no globbing || syntax error)
705  *	debunk to dst
706  *	return ?
707  * - return ?
708  */
709 int
has_globbing(const char * xp,const char * xpe)710 has_globbing(const char *xp, const char *xpe)
711 {
712 	const unsigned char *p = (const unsigned char *) xp;
713 	const unsigned char *pe = (const unsigned char *) xpe;
714 	int c;
715 	int nest = 0, bnest = 0;
716 	bool saw_glob = false;
717 	/* inside [...] */
718 	bool in_bracket = false;
719 
720 	for (; p < pe; p++) {
721 		if (!ISMAGIC(*p))
722 			continue;
723 		if ((c = *++p) == '*' || c == '?')
724 			saw_glob = true;
725 		else if (c == '[') {
726 			if (!in_bracket) {
727 				saw_glob = true;
728 				in_bracket = true;
729 				if (ISMAGIC(p[1]) && p[2] == '!')
730 					p += 2;
731 				if (ISMAGIC(p[1]) && p[2] == ']')
732 					p += 2;
733 			}
734 			/*XXX Do we need to check ranges here? POSIX Q */
735 		} else if (c == ']') {
736 			if (in_bracket) {
737 				if (bnest)
738 					/* [a*(b]) */
739 					return (0);
740 				in_bracket = false;
741 			}
742 		} else if ((c & 0x80) && vstrchr("*+?@! ", c & 0x7f)) {
743 			saw_glob = true;
744 			if (in_bracket)
745 				bnest++;
746 			else
747 				nest++;
748 		} else if (c == '|') {
749 			if (in_bracket && !bnest)
750 				/* *(a[foo|bar]) */
751 				return (0);
752 		} else if (c == /*(*/ ')') {
753 			if (in_bracket) {
754 				if (!bnest--)
755 					/* *(a[b)c] */
756 					return (0);
757 			} else if (nest)
758 				nest--;
759 		}
760 		/*
761 		 * else must be a MAGIC-MAGIC, or MAGIC-!,
762 		 * MAGIC--, MAGIC-], MAGIC-{, MAGIC-, MAGIC-}
763 		 */
764 	}
765 	return (saw_glob && !in_bracket && !nest);
766 }
767 
768 /* Function must return either 0 or 1 (assumed by code for 0x80|'!') */
769 static int
do_gmatch(const unsigned char * s,const unsigned char * se,const unsigned char * p,const unsigned char * pe)770 do_gmatch(const unsigned char *s, const unsigned char *se,
771     const unsigned char *p, const unsigned char *pe)
772 {
773 	unsigned char sc, pc;
774 	const unsigned char *prest, *psub, *pnext;
775 	const unsigned char *srest;
776 
777 	if (s == NULL || p == NULL)
778 		return (0);
779 	while (p < pe) {
780 		pc = *p++;
781 		sc = s < se ? *s : '\0';
782 		s++;
783 		if (!ISMAGIC(pc)) {
784 			if (sc != pc)
785 				return (0);
786 			continue;
787 		}
788 		switch (*p++) {
789 		case '[':
790 			if (sc == 0 || (p = gmatch_cclass(p, sc)) == NULL)
791 				return (0);
792 			break;
793 
794 		case '?':
795 			if (sc == 0)
796 				return (0);
797 			if (UTFMODE) {
798 				--s;
799 				s += utf_ptradj((const void *)s);
800 			}
801 			break;
802 
803 		case '*':
804 			if (p == pe)
805 				return (1);
806 			s--;
807 			do {
808 				if (do_gmatch(s, se, p, pe))
809 					return (1);
810 			} while (s++ < se);
811 			return (0);
812 
813 		/**
814 		 * [*+?@!](pattern|pattern|..)
815 		 * This is also needed for ${..%..}, etc.
816 		 */
817 
818 		/* matches one or more times */
819 		case 0x80|'+':
820 		/* matches zero or more times */
821 		case 0x80|'*':
822 			if (!(prest = pat_scan(p, pe, false)))
823 				return (0);
824 			s--;
825 			/* take care of zero matches */
826 			if (p[-1] == (0x80 | '*') &&
827 			    do_gmatch(s, se, prest, pe))
828 				return (1);
829 			for (psub = p; ; psub = pnext) {
830 				pnext = pat_scan(psub, pe, true);
831 				for (srest = s; srest <= se; srest++) {
832 					if (do_gmatch(s, srest, psub, pnext - 2) &&
833 					    (do_gmatch(srest, se, prest, pe) ||
834 					    (s != srest && do_gmatch(srest,
835 					    se, p - 2, pe))))
836 						return (1);
837 				}
838 				if (pnext == prest)
839 					break;
840 			}
841 			return (0);
842 
843 		/* matches zero or once */
844 		case 0x80|'?':
845 		/* matches one of the patterns */
846 		case 0x80|'@':
847 		/* simile for @ */
848 		case 0x80|' ':
849 			if (!(prest = pat_scan(p, pe, false)))
850 				return (0);
851 			s--;
852 			/* Take care of zero matches */
853 			if (p[-1] == (0x80 | '?') &&
854 			    do_gmatch(s, se, prest, pe))
855 				return (1);
856 			for (psub = p; ; psub = pnext) {
857 				pnext = pat_scan(psub, pe, true);
858 				srest = prest == pe ? se : s;
859 				for (; srest <= se; srest++) {
860 					if (do_gmatch(s, srest, psub, pnext - 2) &&
861 					    do_gmatch(srest, se, prest, pe))
862 						return (1);
863 				}
864 				if (pnext == prest)
865 					break;
866 			}
867 			return (0);
868 
869 		/* matches none of the patterns */
870 		case 0x80|'!':
871 			if (!(prest = pat_scan(p, pe, false)))
872 				return (0);
873 			s--;
874 			for (srest = s; srest <= se; srest++) {
875 				int matched = 0;
876 
877 				for (psub = p; ; psub = pnext) {
878 					pnext = pat_scan(psub, pe, true);
879 					if (do_gmatch(s, srest, psub,
880 					    pnext - 2)) {
881 						matched = 1;
882 						break;
883 					}
884 					if (pnext == prest)
885 						break;
886 				}
887 				if (!matched &&
888 				    do_gmatch(srest, se, prest, pe))
889 					return (1);
890 			}
891 			return (0);
892 
893 		default:
894 			if (sc != p[-1])
895 				return (0);
896 			break;
897 		}
898 	}
899 	return (s == se);
900 }
901 
902 static const unsigned char *
gmatch_cclass(const unsigned char * p,unsigned char sub)903 gmatch_cclass(const unsigned char *p, unsigned char sub)
904 {
905 	unsigned char c, d;
906 	bool notp, found = false;
907 	const unsigned char *orig_p = p;
908 
909 	if ((notp = tobool(ISMAGIC(*p) && *++p == '!')))
910 		p++;
911 	do {
912 		c = *p++;
913 		if (ISMAGIC(c)) {
914 			c = *p++;
915 			if ((c & 0x80) && !ISMAGIC(c)) {
916 				/* extended pattern matching: *+?@! */
917 				c &= 0x7F;
918 				/* XXX the ( char isn't handled as part of [] */
919 				if (c == ' ')
920 					/* simile for @: plain (..) */
921 					c = '(' /*)*/;
922 			}
923 		}
924 		if (c == '\0')
925 			/* No closing ] - act as if the opening [ was quoted */
926 			return (sub == '[' ? orig_p : NULL);
927 		if (ISMAGIC(p[0]) && p[1] == '-' &&
928 		    (!ISMAGIC(p[2]) || p[3] != ']')) {
929 			/* MAGIC- */
930 			p += 2;
931 			d = *p++;
932 			if (ISMAGIC(d)) {
933 				d = *p++;
934 				if ((d & 0x80) && !ISMAGIC(d))
935 					d &= 0x7f;
936 			}
937 			/* POSIX says this is an invalid expression */
938 			if (c > d)
939 				return (NULL);
940 		} else
941 			d = c;
942 		if (c == sub || (c <= sub && sub <= d))
943 			found = true;
944 	} while (!(ISMAGIC(p[0]) && p[1] == ']'));
945 
946 	return ((found != notp) ? p+2 : NULL);
947 }
948 
949 /* Look for next ) or | (if match_sep) in *(foo|bar) pattern */
950 static const unsigned char *
pat_scan(const unsigned char * p,const unsigned char * pe,bool match_sep)951 pat_scan(const unsigned char *p, const unsigned char *pe, bool match_sep)
952 {
953 	int nest = 0;
954 
955 	for (; p < pe; p++) {
956 		if (!ISMAGIC(*p))
957 			continue;
958 		if ((*++p == /*(*/ ')' && nest-- == 0) ||
959 		    (*p == '|' && match_sep && nest == 0))
960 			return (p + 1);
961 		if ((*p & 0x80) && vstrchr("*+?@! ", *p & 0x7f))
962 			nest++;
963 	}
964 	return (NULL);
965 }
966 
967 int
xstrcmp(const void * p1,const void * p2)968 xstrcmp(const void *p1, const void *p2)
969 {
970 	return (strcmp(*(const char * const *)p1, *(const char * const *)p2));
971 }
972 
973 /* Initialise a Getopt structure */
974 void
ksh_getopt_reset(Getopt * go,int flags)975 ksh_getopt_reset(Getopt *go, int flags)
976 {
977 	go->optind = 1;
978 	go->optarg = NULL;
979 	go->p = 0;
980 	go->flags = flags;
981 	go->info = 0;
982 	go->buf[1] = '\0';
983 }
984 
985 
986 /**
987  * getopt() used for shell built-in commands, the getopts command, and
988  * command line options.
989  * A leading ':' in options means don't print errors, instead return '?'
990  * or ':' and set go->optarg to the offending option character.
991  * If GF_ERROR is set (and option doesn't start with :), errors result in
992  * a call to bi_errorf().
993  *
994  * Non-standard features:
995  *	- ';' is like ':' in options, except the argument is optional
996  *	  (if it isn't present, optarg is set to 0).
997  *	  Used for 'set -o'.
998  *	- ',' is like ':' in options, except the argument always immediately
999  *	  follows the option character (optarg is set to the null string if
1000  *	  the option is missing).
1001  *	  Used for 'read -u2', 'print -u2' and fc -40.
1002  *	- '#' is like ':' in options, expect that the argument is optional
1003  *	  and must start with a digit. If the argument doesn't start with a
1004  *	  digit, it is assumed to be missing and normal option processing
1005  *	  continues (optarg is set to 0 if the option is missing).
1006  *	  Used for 'typeset -LZ4'.
1007  *	- accepts +c as well as -c IF the GF_PLUSOPT flag is present. If an
1008  *	  option starting with + is accepted, the GI_PLUS flag will be set
1009  *	  in go->info.
1010  */
1011 int
ksh_getopt(const char ** argv,Getopt * go,const char * optionsp)1012 ksh_getopt(const char **argv, Getopt *go, const char *optionsp)
1013 {
1014 	char c;
1015 	const char *o;
1016 
1017 	if (go->p == 0 || (c = argv[go->optind - 1][go->p]) == '\0') {
1018 		const char *arg = argv[go->optind], flag = arg ? *arg : '\0';
1019 
1020 		go->p = 1;
1021 		if (flag == '-' && ksh_isdash(arg + 1)) {
1022 			go->optind++;
1023 			go->p = 0;
1024 			go->info |= GI_MINUSMINUS;
1025 			return (-1);
1026 		}
1027 		if (arg == NULL ||
1028 		    ((flag != '-' ) &&
1029 		    /* neither a - nor a + (if + allowed) */
1030 		    (!(go->flags & GF_PLUSOPT) || flag != '+')) ||
1031 		    (c = arg[1]) == '\0') {
1032 			go->p = 0;
1033 			return (-1);
1034 		}
1035 		go->optind++;
1036 		go->info &= ~(GI_MINUS|GI_PLUS);
1037 		go->info |= flag == '-' ? GI_MINUS : GI_PLUS;
1038 	}
1039 	go->p++;
1040 	if (c == '?' || c == ':' || c == ';' || c == ',' || c == '#' ||
1041 	    !(o = cstrchr(optionsp, c))) {
1042 		if (optionsp[0] == ':') {
1043 			go->buf[0] = c;
1044 			go->optarg = go->buf;
1045 		} else {
1046 			warningf(true, Tf_optfoo,
1047 			    (go->flags & GF_NONAME) ? "" : argv[0],
1048 			    (go->flags & GF_NONAME) ? "" : Tcolsp,
1049 			    c, Tunknown_option);
1050 			if (go->flags & GF_ERROR)
1051 				bi_errorfz();
1052 		}
1053 		return ('?');
1054 	}
1055 	/**
1056 	 * : means argument must be present, may be part of option argument
1057 	 *   or the next argument
1058 	 * ; same as : but argument may be missing
1059 	 * , means argument is part of option argument, and may be null.
1060 	 */
1061 	if (*++o == ':' || *o == ';') {
1062 		if (argv[go->optind - 1][go->p])
1063 			go->optarg = argv[go->optind - 1] + go->p;
1064 		else if (argv[go->optind])
1065 			go->optarg = argv[go->optind++];
1066 		else if (*o == ';')
1067 			go->optarg = NULL;
1068 		else {
1069 			if (optionsp[0] == ':') {
1070 				go->buf[0] = c;
1071 				go->optarg = go->buf;
1072 				return (':');
1073 			}
1074 			warningf(true, Tf_optfoo,
1075 			    (go->flags & GF_NONAME) ? "" : argv[0],
1076 			    (go->flags & GF_NONAME) ? "" : Tcolsp,
1077 			    c, Treq_arg);
1078 			if (go->flags & GF_ERROR)
1079 				bi_errorfz();
1080 			return ('?');
1081 		}
1082 		go->p = 0;
1083 	} else if (*o == ',') {
1084 		/* argument is attached to option character, even if null */
1085 		go->optarg = argv[go->optind - 1] + go->p;
1086 		go->p = 0;
1087 	} else if (*o == '#') {
1088 		/*
1089 		 * argument is optional and may be attached or unattached
1090 		 * but must start with a digit. optarg is set to 0 if the
1091 		 * argument is missing.
1092 		 */
1093 		if (argv[go->optind - 1][go->p]) {
1094 			if (ksh_isdigit(argv[go->optind - 1][go->p])) {
1095 				go->optarg = argv[go->optind - 1] + go->p;
1096 				go->p = 0;
1097 			} else
1098 				go->optarg = NULL;
1099 		} else {
1100 			if (argv[go->optind] && ksh_isdigit(argv[go->optind][0])) {
1101 				go->optarg = argv[go->optind++];
1102 				go->p = 0;
1103 			} else
1104 				go->optarg = NULL;
1105 		}
1106 	}
1107 	return (c);
1108 }
1109 
1110 /*
1111  * print variable/alias value using necessary quotes
1112  * (POSIX says they should be suitable for re-entry...)
1113  * No trailing newline is printed.
1114  */
1115 void
print_value_quoted(struct shf * shf,const char * s)1116 print_value_quoted(struct shf *shf, const char *s)
1117 {
1118 	unsigned char c;
1119 	const unsigned char *p = (const unsigned char *)s;
1120 	bool inquote = true;
1121 
1122 	/* first, check whether any quotes are needed */
1123 	while ((c = *p++) >= 32)
1124 		if (ctype(c, C_QUOTE))
1125 			inquote = false;
1126 
1127 	p = (const unsigned char *)s;
1128 	if (c == 0) {
1129 		if (inquote) {
1130 			/* nope, use the shortcut */
1131 			shf_puts(s, shf);
1132 			return;
1133 		}
1134 
1135 		/* otherwise, quote nicely via state machine */
1136 		while ((c = *p++) != 0) {
1137 			if (c == '\'') {
1138 				/*
1139 				 * multiple single quotes or any of them
1140 				 * at the beginning of a string look nicer
1141 				 * this way than when simply substituting
1142 				 */
1143 				if (inquote) {
1144 					shf_putc('\'', shf);
1145 					inquote = false;
1146 				}
1147 				shf_putc('\\', shf);
1148 			} else if (!inquote) {
1149 				shf_putc('\'', shf);
1150 				inquote = true;
1151 			}
1152 			shf_putc(c, shf);
1153 		}
1154 	} else {
1155 		unsigned int wc;
1156 		size_t n;
1157 
1158 		/* use $'...' quote format */
1159 		shf_putc('$', shf);
1160 		shf_putc('\'', shf);
1161 		while ((c = *p) != 0) {
1162 			if (c >= 0xC2) {
1163 				n = utf_mbtowc(&wc, (const char *)p);
1164 				if (n != (size_t)-1) {
1165 					p += n;
1166 					shf_fprintf(shf, "\\u%04X", wc);
1167 					continue;
1168 				}
1169 			}
1170 			++p;
1171 			switch (c) {
1172 			/* see unbksl() in this file for comments */
1173 			case 7:
1174 				c = 'a';
1175 				if (0)
1176 					/* FALLTHROUGH */
1177 			case '\b':
1178 				  c = 'b';
1179 				if (0)
1180 					/* FALLTHROUGH */
1181 			case '\f':
1182 				  c = 'f';
1183 				if (0)
1184 					/* FALLTHROUGH */
1185 			case '\n':
1186 				  c = 'n';
1187 				if (0)
1188 					/* FALLTHROUGH */
1189 			case '\r':
1190 				  c = 'r';
1191 				if (0)
1192 					/* FALLTHROUGH */
1193 			case '\t':
1194 				  c = 't';
1195 				if (0)
1196 					/* FALLTHROUGH */
1197 			case 11:
1198 				  c = 'v';
1199 				if (0)
1200 					/* FALLTHROUGH */
1201 			case '\033':
1202 				/* take E not e because \e is \ in *roff */
1203 				  c = 'E';
1204 				/* FALLTHROUGH */
1205 			case '\\':
1206 				shf_putc('\\', shf);
1207 
1208 				if (0)
1209 					/* FALLTHROUGH */
1210 			default:
1211 				  if (c < 32 || c > 0x7E) {
1212 					/* FALLTHROUGH */
1213 			case '\'':
1214 					shf_fprintf(shf, "\\%03o", c);
1215 					break;
1216 				}
1217 
1218 				shf_putc(c, shf);
1219 				break;
1220 			}
1221 		}
1222 		inquote = true;
1223 	}
1224 	if (inquote)
1225 		shf_putc('\'', shf);
1226 }
1227 
1228 /*
1229  * Print things in columns and rows - func() is called to format
1230  * the i-th element
1231  */
1232 void
print_columns(struct columnise_opts * opts,unsigned int n,void (* func)(char *,size_t,unsigned int,const void *),const void * arg,size_t max_oct,size_t max_colz)1233 print_columns(struct columnise_opts *opts, unsigned int n,
1234     void (*func)(char *, size_t, unsigned int, const void *),
1235     const void *arg, size_t max_oct, size_t max_colz)
1236 {
1237 	unsigned int i, r = 0, c, rows, cols, nspace, max_col;
1238 	char *str;
1239 
1240 	if (!n)
1241 		return;
1242 
1243 	if (max_colz > 2147483646) {
1244 #ifndef MKSH_SMALL
1245 		internal_warningf("print_columns called with %s=%zu >= INT_MAX",
1246 		    "max_col", max_colz);
1247 #endif
1248 		return;
1249 	}
1250 	max_col = (unsigned int)max_colz;
1251 
1252 	if (max_oct > 2147483646) {
1253 #ifndef MKSH_SMALL
1254 		internal_warningf("print_columns called with %s=%zu >= INT_MAX",
1255 		    "max_oct", max_oct);
1256 #endif
1257 		return;
1258 	}
1259 	++max_oct;
1260 	str = alloc(max_oct, ATEMP);
1261 
1262 	/*
1263 	 * We use (max_col + 2) to consider the separator space.
1264 	 * Note that no spaces are printed after the last column
1265 	 * to avoid problems with terminals that have auto-wrap,
1266 	 * but we need to also take this into account in x_cols.
1267 	 */
1268 	cols = (x_cols + 1) / (max_col + 2);
1269 
1270 	/* if we can only print one column anyway, skip the goo */
1271 	if (cols < 2) {
1272 		goto prcols_easy;
1273 		while (r < n) {
1274 			shf_putc(opts->linesep, opts->shf);
1275  prcols_easy:
1276 			(*func)(str, max_oct, r++, arg);
1277 			shf_puts(str, opts->shf);
1278 		}
1279 		goto out;
1280 	}
1281 
1282 	rows = (n + cols - 1) / cols;
1283 	if (opts->prefcol && cols > rows) {
1284 		cols = rows;
1285 		rows = (n + cols - 1) / cols;
1286 	}
1287 
1288 	nspace = (x_cols - max_col * cols) / cols;
1289 	if (nspace < 2)
1290 		nspace = 2;
1291 	max_col = -max_col;
1292 	goto prcols_hard;
1293 	while (r < rows) {
1294 		shf_putchar(opts->linesep, opts->shf);
1295  prcols_hard:
1296 		for (c = 0; c < cols; c++) {
1297 			if ((i = c * rows + r) >= n)
1298 				break;
1299 			(*func)(str, max_oct, i, arg);
1300 			if (i + rows >= n)
1301 				shf_puts(str, opts->shf);
1302 			else
1303 				shf_fprintf(opts->shf, "%*s%*s",
1304 				    (int)max_col, str, (int)nspace, null);
1305 		}
1306 		++r;
1307 	}
1308  out:
1309 	if (opts->do_last)
1310 		shf_putchar(opts->linesep, opts->shf);
1311 	afree(str, ATEMP);
1312 }
1313 
1314 /* strip all NUL bytes from buf; output is NUL-terminated if stripped */
1315 void
strip_nuls(char * buf,size_t len)1316 strip_nuls(char *buf, size_t len)
1317 {
1318 	char *cp, *dp, *ep;
1319 
1320 	if (!len || !(dp = memchr(buf, '\0', len)))
1321 		return;
1322 
1323 	ep = buf + len;
1324 	cp = dp;
1325 
1326  cp_has_nul_byte:
1327 	while (cp++ < ep && *cp == '\0')
1328 		;	/* nothing */
1329 	while (cp < ep && *cp != '\0')
1330 		*dp++ = *cp++;
1331 	if (cp < ep)
1332 		goto cp_has_nul_byte;
1333 
1334 	*dp = '\0';
1335 }
1336 
1337 /*
1338  * Like read(2), but if read fails due to non-blocking flag,
1339  * resets flag and restarts read.
1340  */
1341 ssize_t
blocking_read(int fd,char * buf,size_t nbytes)1342 blocking_read(int fd, char *buf, size_t nbytes)
1343 {
1344 	ssize_t ret;
1345 	bool tried_reset = false;
1346 
1347 	while ((ret = read(fd, buf, nbytes)) < 0) {
1348 		if (!tried_reset && errno == EAGAIN) {
1349 			if (reset_nonblock(fd) > 0) {
1350 				tried_reset = true;
1351 				continue;
1352 			}
1353 			errno = EAGAIN;
1354 		}
1355 		break;
1356 	}
1357 	return (ret);
1358 }
1359 
1360 /*
1361  * Reset the non-blocking flag on the specified file descriptor.
1362  * Returns -1 if there was an error, 0 if non-blocking wasn't set,
1363  * 1 if it was.
1364  */
1365 int
reset_nonblock(int fd)1366 reset_nonblock(int fd)
1367 {
1368 	int flags;
1369 
1370 	if ((flags = fcntl(fd, F_GETFL, 0)) < 0)
1371 		return (-1);
1372 	if (!(flags & O_NONBLOCK))
1373 		return (0);
1374 	flags &= ~O_NONBLOCK;
1375 	if (fcntl(fd, F_SETFL, flags) < 0)
1376 		return (-1);
1377 	return (1);
1378 }
1379 
1380 /* getcwd(3) equivalent, allocates from ATEMP but doesn't resize */
1381 char *
ksh_get_wd(void)1382 ksh_get_wd(void)
1383 {
1384 #ifdef MKSH__NO_PATH_MAX
1385 	char *rv, *cp;
1386 
1387 	if ((cp = get_current_dir_name())) {
1388 		strdupx(rv, cp, ATEMP);
1389 		free_gnu_gcdn(cp);
1390 	} else
1391 		rv = NULL;
1392 #else
1393 	char *rv;
1394 
1395 	if (!getcwd((rv = alloc(PATH_MAX + 1, ATEMP)), PATH_MAX)) {
1396 		afree(rv, ATEMP);
1397 		rv = NULL;
1398 	}
1399 #endif
1400 
1401 	return (rv);
1402 }
1403 
1404 #ifndef ELOOP
1405 #define ELOOP		E2BIG
1406 #endif
1407 
1408 char *
do_realpath(const char * upath)1409 do_realpath(const char *upath)
1410 {
1411 	char *xp, *ip, *tp, *ipath, *ldest = NULL;
1412 	XString xs;
1413 	size_t pos, len;
1414 	int llen;
1415 	struct stat sb;
1416 #ifdef MKSH__NO_PATH_MAX
1417 	size_t ldestlen = 0;
1418 #define pathlen sb.st_size
1419 #define pathcnd (ldestlen < (pathlen + 1))
1420 #else
1421 #define pathlen PATH_MAX
1422 #define pathcnd (!ldest)
1423 #endif
1424 	/* max. recursion depth */
1425 	int symlinks = 32;
1426 
1427 	if (mksh_abspath(upath)) {
1428 		/* upath is an absolute pathname */
1429 		strdupx(ipath, upath, ATEMP);
1430 	} else {
1431 		/* upath is a relative pathname, prepend cwd */
1432 		if ((tp = ksh_get_wd()) == NULL || !mksh_abspath(tp))
1433 			return (NULL);
1434 		ipath = shf_smprintf(Tf_sss, tp, "/", upath);
1435 		afree(tp, ATEMP);
1436 	}
1437 
1438 	/* ipath and upath are in memory at the same time -> unchecked */
1439 	Xinit(xs, xp, strlen(ip = ipath) + 1, ATEMP);
1440 
1441 	/* now jump into the deep of the loop */
1442 	goto beginning_of_a_pathname;
1443 
1444 	while (*ip) {
1445 		/* skip slashes in input */
1446 		while (mksh_cdirsep(*ip))
1447 			++ip;
1448 		if (!*ip)
1449 			break;
1450 
1451 		/* get next pathname component from input */
1452 		tp = ip;
1453 		while (*ip && !mksh_cdirsep(*ip))
1454 			++ip;
1455 		len = ip - tp;
1456 
1457 		/* check input for "." and ".." */
1458 		if (tp[0] == '.') {
1459 			if (len == 1)
1460 				/* just continue with the next one */
1461 				continue;
1462 			else if (len == 2 && tp[1] == '.') {
1463 				/* strip off last pathname component */
1464 				while (xp > Xstring(xs, xp))
1465 					if (mksh_cdirsep(*--xp))
1466 						break;
1467 				/* then continue with the next one */
1468 				continue;
1469 			}
1470 		}
1471 
1472 		/* store output position away, then append slash to output */
1473 		pos = Xsavepos(xs, xp);
1474 		/* 1 for the '/' and len + 1 for tp and the NUL from below */
1475 		XcheckN(xs, xp, 1 + len + 1);
1476 		Xput(xs, xp, '/');
1477 
1478 		/* append next pathname component to output */
1479 		memcpy(xp, tp, len);
1480 		xp += len;
1481 		*xp = '\0';
1482 
1483 		/* lstat the current output, see if it's a symlink */
1484 		if (mksh_lstat(Xstring(xs, xp), &sb)) {
1485 			/* lstat failed */
1486 			if (errno == ENOENT) {
1487 				/* because the pathname does not exist */
1488 				while (mksh_cdirsep(*ip))
1489 					/* skip any trailing slashes */
1490 					++ip;
1491 				/* no more components left? */
1492 				if (!*ip)
1493 					/* we can still return successfully */
1494 					break;
1495 				/* more components left? fall through */
1496 			}
1497 			/* not ENOENT or not at the end of ipath */
1498 			goto notfound;
1499 		}
1500 
1501 		/* check if we encountered a symlink? */
1502 		if (S_ISLNK(sb.st_mode)) {
1503 #ifndef MKSH__NO_SYMLINK
1504 			/* reached maximum recursion depth? */
1505 			if (!symlinks--) {
1506 				/* yep, prevent infinite loops */
1507 				errno = ELOOP;
1508 				goto notfound;
1509 			}
1510 
1511 			/* get symlink(7) target */
1512 			if (pathcnd) {
1513 #ifdef MKSH__NO_PATH_MAX
1514 				if (notoktoadd(pathlen, 1)) {
1515 					errno = ENAMETOOLONG;
1516 					goto notfound;
1517 				}
1518 #endif
1519 				ldest = aresize(ldest, pathlen + 1, ATEMP);
1520 			}
1521 			llen = readlink(Xstring(xs, xp), ldest, pathlen);
1522 			if (llen < 0)
1523 				/* oops... */
1524 				goto notfound;
1525 			ldest[llen] = '\0';
1526 
1527 			/*
1528 			 * restart if symlink target is an absolute path,
1529 			 * otherwise continue with currently resolved prefix
1530 			 */
1531 			/* append rest of current input path to link target */
1532 			tp = shf_smprintf(Tf_sss, ldest, *ip ? "/" : "", ip);
1533 			afree(ipath, ATEMP);
1534 			ip = ipath = tp;
1535 			if (!mksh_abspath(ldest)) {
1536 				/* symlink target is a relative path */
1537 				xp = Xrestpos(xs, xp, pos);
1538 			} else
1539 #endif
1540 			  {
1541 				/* symlink target is an absolute path */
1542 				xp = Xstring(xs, xp);
1543  beginning_of_a_pathname:
1544 				/* assert: (ip == ipath)[0] == '/' */
1545 				/* assert: xp == xs.beg => start of path */
1546 
1547 				/* exactly two leading slashes? (SUSv4 3.266) */
1548 				/* @komh do NOT use mksh_cdirsep() here */
1549 				if (ip[1] == '/' && ip[2] != '/') {
1550 					/* keep them, e.g. for UNC pathnames */
1551 					Xput(xs, xp, '/');
1552 				}
1553 			}
1554 		}
1555 		/* otherwise (no symlink) merely go on */
1556 	}
1557 
1558 	/*
1559 	 * either found the target and successfully resolved it,
1560 	 * or found its parent directory and may create it
1561 	 */
1562 	if (Xlength(xs, xp) == 0)
1563 		/*
1564 		 * if the resolved pathname is "", make it "/",
1565 		 * otherwise do not add a trailing slash
1566 		 */
1567 		Xput(xs, xp, '/');
1568 	Xput(xs, xp, '\0');
1569 
1570 	/*
1571 	 * if source path had a trailing slash, check if target path
1572 	 * is not a non-directory existing file
1573 	 */
1574 	if (ip > ipath && mksh_cdirsep(ip[-1])) {
1575 		if (stat(Xstring(xs, xp), &sb)) {
1576 			if (errno != ENOENT)
1577 				goto notfound;
1578 		} else if (!S_ISDIR(sb.st_mode)) {
1579 			errno = ENOTDIR;
1580 			goto notfound;
1581 		}
1582 		/* target now either does not exist or is a directory */
1583 	}
1584 
1585 	/* return target path */
1586 	afree(ldest, ATEMP);
1587 	afree(ipath, ATEMP);
1588 	return (Xclose(xs, xp));
1589 
1590  notfound:
1591 	/* save; freeing memory might trash it */
1592 	llen = errno;
1593 	afree(ldest, ATEMP);
1594 	afree(ipath, ATEMP);
1595 	Xfree(xs, xp);
1596 	errno = llen;
1597 	return (NULL);
1598 
1599 #undef pathlen
1600 #undef pathcnd
1601 }
1602 
1603 /**
1604  *	Makes a filename into result using the following algorithm.
1605  *	- make result NULL
1606  *	- if file starts with '/', append file to result & set cdpathp to NULL
1607  *	- if file starts with ./ or ../ append cwd and file to result
1608  *	  and set cdpathp to NULL
1609  *	- if the first element of cdpathp doesnt start with a '/' xx or '.' xx
1610  *	  then cwd is appended to result.
1611  *	- the first element of cdpathp is appended to result
1612  *	- file is appended to result
1613  *	- cdpathp is set to the start of the next element in cdpathp (or NULL
1614  *	  if there are no more elements.
1615  *	The return value indicates whether a non-null element from cdpathp
1616  *	was appended to result.
1617  */
1618 static int
make_path(const char * cwd,const char * file,char ** cdpathp,XString * xsp,int * phys_pathp)1619 make_path(const char *cwd, const char *file,
1620     /* pointer to colon-separated list */
1621     char **cdpathp,
1622     XString *xsp,
1623     int *phys_pathp)
1624 {
1625 	int rval = 0;
1626 	bool use_cdpath = true;
1627 	char *plist;
1628 	size_t len, plen = 0;
1629 	char *xp = Xstring(*xsp, xp);
1630 
1631 	if (!file)
1632 		file = null;
1633 
1634 	if (mksh_abspath(file)) {
1635 		*phys_pathp = 0;
1636 		use_cdpath = false;
1637 	} else {
1638 		if (file[0] == '.') {
1639 			char c = file[1];
1640 
1641 			if (c == '.')
1642 				c = file[2];
1643 			if (mksh_cdirsep(c) || c == '\0')
1644 				use_cdpath = false;
1645 		}
1646 
1647 		plist = *cdpathp;
1648 		if (!plist)
1649 			use_cdpath = false;
1650 		else if (use_cdpath) {
1651 			char *pend = plist;
1652 
1653 			while (*pend && *pend != MKSH_PATHSEPC)
1654 				++pend;
1655 			plen = pend - plist;
1656 			*cdpathp = *pend ? pend + 1 : NULL;
1657 		}
1658 
1659 		if ((!use_cdpath || !plen || !mksh_abspath(plist)) &&
1660 		    (cwd && *cwd)) {
1661 			len = strlen(cwd);
1662 			XcheckN(*xsp, xp, len);
1663 			memcpy(xp, cwd, len);
1664 			xp += len;
1665 			if (!mksh_cdirsep(cwd[len - 1]))
1666 				Xput(*xsp, xp, '/');
1667 		}
1668 		*phys_pathp = Xlength(*xsp, xp);
1669 		if (use_cdpath && plen) {
1670 			XcheckN(*xsp, xp, plen);
1671 			memcpy(xp, plist, plen);
1672 			xp += plen;
1673 			if (!mksh_cdirsep(plist[plen - 1]))
1674 				Xput(*xsp, xp, '/');
1675 			rval = 1;
1676 		}
1677 	}
1678 
1679 	len = strlen(file) + 1;
1680 	XcheckN(*xsp, xp, len);
1681 	memcpy(xp, file, len);
1682 
1683 	if (!use_cdpath)
1684 		*cdpathp = NULL;
1685 
1686 	return (rval);
1687 }
1688 
1689 /*-
1690  * Simplify pathnames containing "." and ".." entries.
1691  *
1692  * simplify_path(this)			= that
1693  * /a/b/c/./../d/..			/a/b
1694  * //./C/foo/bar/../baz			//C/foo/baz
1695  * /foo/				/foo
1696  * /foo/../../bar			/bar
1697  * /foo/./blah/..			/foo
1698  * .					.
1699  * ..					..
1700  * ./foo				foo
1701  * foo/../../../bar			../../bar
1702  */
1703 void
simplify_path(char * p)1704 simplify_path(char *p)
1705 {
1706 	char *dp, *ip, *sp, *tp;
1707 	size_t len;
1708 	bool needslash;
1709 
1710 	switch (*p) {
1711 	case 0:
1712 		return;
1713 	case '/':
1714 		/* exactly two leading slashes? (SUSv4 3.266) */
1715 		/* @komh no mksh_cdirsep() here! */
1716 		if (p[1] == '/' && p[2] != '/')
1717 			/* keep them, e.g. for UNC pathnames */
1718 			++p;
1719 #ifdef __OS2__
1720 		/* FALLTHROUGH */
1721 	case '\\':
1722 #endif
1723 		needslash = true;
1724 		break;
1725 	default:
1726 		needslash = false;
1727 	}
1728 	dp = ip = sp = p;
1729 
1730 	while (*ip) {
1731 		/* skip slashes in input */
1732 		while (mksh_cdirsep(*ip))
1733 			++ip;
1734 		if (!*ip)
1735 			break;
1736 
1737 		/* get next pathname component from input */
1738 		tp = ip;
1739 		while (*ip && !mksh_cdirsep(*ip))
1740 			++ip;
1741 		len = ip - tp;
1742 
1743 		/* check input for "." and ".." */
1744 		if (tp[0] == '.') {
1745 			if (len == 1)
1746 				/* just continue with the next one */
1747 				continue;
1748 			else if (len == 2 && tp[1] == '.') {
1749 				/* parent level, but how? */
1750 				if (mksh_abspath(p))
1751 					/* absolute path, only one way */
1752 					goto strip_last_component;
1753 				else if (dp > sp) {
1754 					/* relative path, with subpaths */
1755 					needslash = false;
1756  strip_last_component:
1757 					/* strip off last pathname component */
1758 					while (dp > sp)
1759 						if (mksh_cdirsep(*--dp))
1760 							break;
1761 				} else {
1762 					/* relative path, at its beginning */
1763 					if (needslash)
1764 						/* or already dotdot-slash'd */
1765 						*dp++ = '/';
1766 					/* keep dotdot-slash if not absolute */
1767 					*dp++ = '.';
1768 					*dp++ = '.';
1769 					needslash = true;
1770 					sp = dp;
1771 				}
1772 				/* then continue with the next one */
1773 				continue;
1774 			}
1775 		}
1776 
1777 		if (needslash)
1778 			*dp++ = '/';
1779 
1780 		/* append next pathname component to output */
1781 		memmove(dp, tp, len);
1782 		dp += len;
1783 
1784 		/* append slash if we continue */
1785 		needslash = true;
1786 		/* try next component */
1787 	}
1788 	if (dp == p)
1789 		/* empty path -> dot */
1790 		*dp++ = needslash ? '/' : '.';
1791 	*dp = '\0';
1792 }
1793 
1794 void
set_current_wd(const char * nwd)1795 set_current_wd(const char *nwd)
1796 {
1797 	char *allocd = NULL;
1798 
1799 	if (nwd == NULL) {
1800 		allocd = ksh_get_wd();
1801 		nwd = allocd ? allocd : null;
1802 	}
1803 
1804 	afree(current_wd, APERM);
1805 	strdupx(current_wd, nwd, APERM);
1806 
1807 	afree(allocd, ATEMP);
1808 }
1809 
1810 int
c_cd(const char ** wp)1811 c_cd(const char **wp)
1812 {
1813 	int optc, rv, phys_path;
1814 	bool physical = tobool(Flag(FPHYSICAL));
1815 	/* was a node from cdpath added in? */
1816 	int cdnode;
1817 	/* show where we went?, error for $PWD */
1818 	bool printpath = false, eflag = false;
1819 	struct tbl *pwd_s, *oldpwd_s;
1820 	XString xs;
1821 	char *dir, *allocd = NULL, *tryp, *pwd, *cdpath;
1822 
1823 	while ((optc = ksh_getopt(wp, &builtin_opt, "eLP")) != -1)
1824 		switch (optc) {
1825 		case 'e':
1826 			eflag = true;
1827 			break;
1828 		case 'L':
1829 			physical = false;
1830 			break;
1831 		case 'P':
1832 			physical = true;
1833 			break;
1834 		case '?':
1835 			return (2);
1836 		}
1837 	wp += builtin_opt.optind;
1838 
1839 	if (Flag(FRESTRICTED)) {
1840 		bi_errorf(Tcant_cd);
1841 		return (2);
1842 	}
1843 
1844 	pwd_s = global(TPWD);
1845 	oldpwd_s = global(TOLDPWD);
1846 
1847 	if (!wp[0]) {
1848 		/* No arguments - go home */
1849 		if ((dir = str_val(global("HOME"))) == null) {
1850 			bi_errorf("no home directory (HOME not set)");
1851 			return (2);
1852 		}
1853 	} else if (!wp[1]) {
1854 		/* One argument: - or dir */
1855 		strdupx(allocd, wp[0], ATEMP);
1856 		if (ksh_isdash((dir = allocd))) {
1857 			afree(allocd, ATEMP);
1858 			allocd = NULL;
1859 			dir = str_val(oldpwd_s);
1860 			if (dir == null) {
1861 				bi_errorf(Tno_OLDPWD);
1862 				return (2);
1863 			}
1864 			printpath = true;
1865 		}
1866 	} else if (!wp[2]) {
1867 		/* Two arguments - substitute arg1 in PWD for arg2 */
1868 		size_t ilen, olen, nlen, elen;
1869 		char *cp;
1870 
1871 		if (!current_wd[0]) {
1872 			bi_errorf("can't determine current directory");
1873 			return (2);
1874 		}
1875 		/*
1876 		 * substitute arg1 for arg2 in current path.
1877 		 * if the first substitution fails because the cd fails
1878 		 * we could try to find another substitution. For now
1879 		 * we don't
1880 		 */
1881 		if ((cp = strstr(current_wd, wp[0])) == NULL) {
1882 			bi_errorf(Tbadsubst);
1883 			return (2);
1884 		}
1885 		/*-
1886 		 * ilen = part of current_wd before wp[0]
1887 		 * elen = part of current_wd after wp[0]
1888 		 * because current_wd and wp[1] need to be in memory at the
1889 		 * same time beforehand the addition can stay unchecked
1890 		 */
1891 		ilen = cp - current_wd;
1892 		olen = strlen(wp[0]);
1893 		nlen = strlen(wp[1]);
1894 		elen = strlen(current_wd + ilen + olen) + 1;
1895 		dir = allocd = alloc(ilen + nlen + elen, ATEMP);
1896 		memcpy(dir, current_wd, ilen);
1897 		memcpy(dir + ilen, wp[1], nlen);
1898 		memcpy(dir + ilen + nlen, current_wd + ilen + olen, elen);
1899 		printpath = true;
1900 	} else {
1901 		bi_errorf(Ttoo_many_args);
1902 		return (2);
1903 	}
1904 
1905 #ifdef MKSH__NO_PATH_MAX
1906 	/* only a first guess; make_path will enlarge xs if necessary */
1907 	XinitN(xs, 1024, ATEMP);
1908 #else
1909 	XinitN(xs, PATH_MAX, ATEMP);
1910 #endif
1911 
1912 	cdpath = str_val(global("CDPATH"));
1913 	do {
1914 		cdnode = make_path(current_wd, dir, &cdpath, &xs, &phys_path);
1915 		if (physical)
1916 			rv = chdir(tryp = Xstring(xs, xp) + phys_path);
1917 		else {
1918 			simplify_path(Xstring(xs, xp));
1919 			rv = chdir(tryp = Xstring(xs, xp));
1920 		}
1921 	} while (rv < 0 && cdpath != NULL);
1922 
1923 	if (rv < 0) {
1924 		if (cdnode)
1925 			bi_errorf(Tf_sD_s, dir, "bad directory");
1926 		else
1927 			bi_errorf(Tf_sD_s, tryp, cstrerror(errno));
1928 		afree(allocd, ATEMP);
1929 		Xfree(xs, xp);
1930 		return (2);
1931 	}
1932 
1933 	rv = 0;
1934 
1935 	/* allocd (above) => dir, which is no longer used */
1936 	afree(allocd, ATEMP);
1937 	allocd = NULL;
1938 
1939 	/* Clear out tracked aliases with relative paths */
1940 	flushcom(false);
1941 
1942 	/*
1943 	 * Set OLDPWD (note: unsetting OLDPWD does not disable this
1944 	 * setting in AT&T ksh)
1945 	 */
1946 	if (current_wd[0])
1947 		/* Ignore failure (happens if readonly or integer) */
1948 		setstr(oldpwd_s, current_wd, KSH_RETURN_ERROR);
1949 
1950 	if (!mksh_abspath(Xstring(xs, xp))) {
1951 		pwd = NULL;
1952 	} else if (!physical) {
1953 		goto norealpath_PWD;
1954 	} else if ((pwd = allocd = do_realpath(Xstring(xs, xp))) == NULL) {
1955 		if (eflag)
1956 			rv = 1;
1957  norealpath_PWD:
1958 		pwd = Xstring(xs, xp);
1959 	}
1960 
1961 	/* Set PWD */
1962 	if (pwd) {
1963 		char *ptmp = pwd;
1964 
1965 		set_current_wd(ptmp);
1966 		/* Ignore failure (happens if readonly or integer) */
1967 		setstr(pwd_s, ptmp, KSH_RETURN_ERROR);
1968 	} else {
1969 		set_current_wd(null);
1970 		pwd = Xstring(xs, xp);
1971 		/* XXX unset $PWD? */
1972 		if (eflag)
1973 			rv = 1;
1974 	}
1975 	if (printpath || cdnode)
1976 		shprintf(Tf_sN, pwd);
1977 
1978 	afree(allocd, ATEMP);
1979 	Xfree(xs, xp);
1980 	return (rv);
1981 }
1982 
1983 
1984 #ifdef KSH_CHVT_CODE
1985 extern void chvt_reinit(void);
1986 
1987 static void
chvt(const Getopt * go)1988 chvt(const Getopt *go)
1989 {
1990 	const char *dv = go->optarg;
1991 	char *cp = NULL;
1992 	int fd;
1993 
1994 	switch (*dv) {
1995 	case '-':
1996 		dv = "/dev/null";
1997 		break;
1998 	case '!':
1999 		++dv;
2000 		/* FALLTHROUGH */
2001 	default: {
2002 		struct stat sb;
2003 
2004 		if (stat(dv, &sb)) {
2005 			cp = shf_smprintf("/dev/ttyC%s", dv);
2006 			dv = cp;
2007 			if (stat(dv, &sb)) {
2008 				memmove(cp + 1, cp, /* /dev/tty */ 8);
2009 				dv = cp + 1;
2010 				if (stat(dv, &sb)) {
2011 					errorf(Tf_sD_sD_s, "chvt",
2012 					    "can't find tty", go->optarg);
2013 				}
2014 			}
2015 		}
2016 		if (!(sb.st_mode & S_IFCHR))
2017 			errorf(Tf_sD_sD_s, "chvt", "not a char device", dv);
2018 #ifndef MKSH_DISABLE_REVOKE_WARNING
2019 #if HAVE_REVOKE
2020 		if (revoke(dv))
2021 #endif
2022 			warningf(false, Tf_sD_s_s, "chvt",
2023 			    "new shell is potentially insecure, can't revoke",
2024 			    dv);
2025 #endif
2026 	    }
2027 	}
2028 	if ((fd = binopen2(dv, O_RDWR)) < 0) {
2029 		sleep(1);
2030 		if ((fd = binopen2(dv, O_RDWR)) < 0) {
2031 			errorf(Tf_sD_s_s, "chvt", Tcant_open, dv);
2032 		}
2033 	}
2034 	if (go->optarg[0] != '!') {
2035 		switch (fork()) {
2036 		case -1:
2037 			errorf(Tf_sD_s_s, "chvt", "fork", "failed");
2038 		case 0:
2039 			break;
2040 		default:
2041 			exit(0);
2042 		}
2043 	}
2044 	if (setsid() == -1)
2045 		errorf(Tf_sD_s_s, "chvt", "setsid", "failed");
2046 	if (go->optarg[0] != '-') {
2047 		if (ioctl(fd, TIOCSCTTY, NULL) == -1)
2048 			errorf(Tf_sD_s_s, "chvt", "TIOCSCTTY", "failed");
2049 		if (tcflush(fd, TCIOFLUSH))
2050 			errorf(Tf_sD_s_s, "chvt", "TCIOFLUSH", "failed");
2051 	}
2052 	ksh_dup2(fd, 0, false);
2053 	ksh_dup2(fd, 1, false);
2054 	ksh_dup2(fd, 2, false);
2055 	if (fd > 2)
2056 		close(fd);
2057 	rndset((unsigned long)chvt_rndsetup(go, sizeof(Getopt)));
2058 	chvt_reinit();
2059 }
2060 #endif
2061 
2062 #ifdef DEBUG
2063 char *
strchr(char * p,int ch)2064 strchr(char *p, int ch)
2065 {
2066 	for (;; ++p) {
2067 		if (*p == ch)
2068 			return (p);
2069 		if (!*p)
2070 			return (NULL);
2071 	}
2072 	/* NOTREACHED */
2073 }
2074 
2075 char *
strstr(char * b,const char * l)2076 strstr(char *b, const char *l)
2077 {
2078 	char first, c;
2079 	size_t n;
2080 
2081 	if ((first = *l++) == '\0')
2082 		return (b);
2083 	n = strlen(l);
2084  strstr_look:
2085 	while ((c = *b++) != first)
2086 		if (c == '\0')
2087 			return (NULL);
2088 	if (strncmp(b, l, n))
2089 		goto strstr_look;
2090 	return (b - 1);
2091 }
2092 #endif
2093 
2094 #if defined(MKSH_SMALL) && !defined(MKSH_SMALL_BUT_FAST)
2095 char *
strndup_i(const char * src,size_t len,Area * ap)2096 strndup_i(const char *src, size_t len, Area *ap)
2097 {
2098 	char *dst = NULL;
2099 
2100 	if (src != NULL) {
2101 		dst = alloc(len + 1, ap);
2102 		memcpy(dst, src, len);
2103 		dst[len] = '\0';
2104 	}
2105 	return (dst);
2106 }
2107 
2108 char *
strdup_i(const char * src,Area * ap)2109 strdup_i(const char *src, Area *ap)
2110 {
2111 	return (src == NULL ? NULL : strndup_i(src, strlen(src), ap));
2112 }
2113 #endif
2114 
2115 #if !HAVE_GETRUSAGE
2116 #define INVTCK(r,t)	do {						\
2117 	r.tv_usec = ((t) % (1000000 / CLK_TCK)) * (1000000 / CLK_TCK);	\
2118 	r.tv_sec = (t) / CLK_TCK;					\
2119 } while (/* CONSTCOND */ 0)
2120 
2121 int
getrusage(int what,struct rusage * ru)2122 getrusage(int what, struct rusage *ru)
2123 {
2124 	struct tms tms;
2125 	clock_t u, s;
2126 
2127 	if (/* ru == NULL || */ times(&tms) == (clock_t)-1)
2128 		return (-1);
2129 
2130 	switch (what) {
2131 	case RUSAGE_SELF:
2132 		u = tms.tms_utime;
2133 		s = tms.tms_stime;
2134 		break;
2135 	case RUSAGE_CHILDREN:
2136 		u = tms.tms_cutime;
2137 		s = tms.tms_cstime;
2138 		break;
2139 	default:
2140 		errno = EINVAL;
2141 		return (-1);
2142 	}
2143 	INVTCK(ru->ru_utime, u);
2144 	INVTCK(ru->ru_stime, s);
2145 	return (0);
2146 }
2147 #endif
2148 
2149 /*
2150  * process the string available via fg (get a char)
2151  * and fp (put back a char) for backslash escapes,
2152  * assuming the first call to *fg gets the char di-
2153  * rectly after the backslash; return the character
2154  * (0..0xFF), Unicode (wc + 0x100), or -1 if no known
2155  * escape sequence was found
2156  */
2157 int
unbksl(bool cstyle,int (* fg)(void),void (* fp)(int))2158 unbksl(bool cstyle, int (*fg)(void), void (*fp)(int))
2159 {
2160 	int wc, i, c, fc;
2161 
2162 	fc = (*fg)();
2163 	switch (fc) {
2164 	case 'a':
2165 		/*
2166 		 * according to the comments in pdksh, \007 seems
2167 		 * to be more portable than \a (due to HP-UX cc,
2168 		 * Ultrix cc, old pcc, etc.) so we avoid the escape
2169 		 * sequence altogether in mksh and assume ASCII
2170 		 */
2171 		wc = 7;
2172 		break;
2173 	case 'b':
2174 		wc = '\b';
2175 		break;
2176 	case 'c':
2177 		if (!cstyle)
2178 			goto unknown_escape;
2179 		c = (*fg)();
2180 		wc = CTRL(c);
2181 		break;
2182 	case 'E':
2183 	case 'e':
2184 		wc = 033;
2185 		break;
2186 	case 'f':
2187 		wc = '\f';
2188 		break;
2189 	case 'n':
2190 		wc = '\n';
2191 		break;
2192 	case 'r':
2193 		wc = '\r';
2194 		break;
2195 	case 't':
2196 		wc = '\t';
2197 		break;
2198 	case 'v':
2199 		/* assume ASCII here as well */
2200 		wc = 11;
2201 		break;
2202 	case '1':
2203 	case '2':
2204 	case '3':
2205 	case '4':
2206 	case '5':
2207 	case '6':
2208 	case '7':
2209 		if (!cstyle)
2210 			goto unknown_escape;
2211 		/* FALLTHROUGH */
2212 	case '0':
2213 		if (cstyle)
2214 			(*fp)(fc);
2215 		/*
2216 		 * look for an octal number with up to three
2217 		 * digits, not counting the leading zero;
2218 		 * convert it to a raw octet
2219 		 */
2220 		wc = 0;
2221 		i = 3;
2222 		while (i--)
2223 			if ((c = (*fg)()) >= ord('0') && c <= ord('7'))
2224 				wc = (wc << 3) + ksh_numdig(c);
2225 			else {
2226 				(*fp)(c);
2227 				break;
2228 			}
2229 		break;
2230 	case 'U':
2231 		i = 8;
2232 		if (/* CONSTCOND */ 0)
2233 			/* FALLTHROUGH */
2234 	case 'u':
2235 		  i = 4;
2236 		if (/* CONSTCOND */ 0)
2237 			/* FALLTHROUGH */
2238 	case 'x':
2239 		  i = cstyle ? -1 : 2;
2240 		/**
2241 		 * x:	look for a hexadecimal number with up to
2242 		 *	two (C style: arbitrary) digits; convert
2243 		 *	to raw octet (C style: Unicode if >0xFF)
2244 		 * u/U:	look for a hexadecimal number with up to
2245 		 *	four (U: eight) digits; convert to Unicode
2246 		 */
2247 		wc = 0;
2248 		while (i--) {
2249 			wc <<= 4;
2250 			if ((c = (*fg)()) >= ord('0') && c <= ord('9'))
2251 				wc += ksh_numdig(c);
2252 			else if (c >= ord('A') && c <= ord('F'))
2253 				wc += ksh_numuc(c) + 10;
2254 			else if (c >= ord('a') && c <= ord('f'))
2255 				wc += ksh_numlc(c) + 10;
2256 			else {
2257 				wc >>= 4;
2258 				(*fp)(c);
2259 				break;
2260 			}
2261 		}
2262 		if ((cstyle && wc > 0xFF) || fc != 'x')
2263 			/* Unicode marker */
2264 			wc += 0x100;
2265 		break;
2266 	case '\'':
2267 		if (!cstyle)
2268 			goto unknown_escape;
2269 		wc = '\'';
2270 		break;
2271 	case '\\':
2272 		wc = '\\';
2273 		break;
2274 	default:
2275  unknown_escape:
2276 		(*fp)(fc);
2277 		return (-1);
2278 	}
2279 
2280 	return (wc);
2281 }
2282