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glob.c revision 1.8 
      1 /*	$NetBSD: glob.c,v 1.8 1997/10/21 00:56:55 fvdl Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Guido van Rossum.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the University of
     21  *	California, Berkeley and its contributors.
     22  * 4. Neither the name of the University nor the names of its contributors
     23  *    may be used to endorse or promote products derived from this software
     24  *    without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36  * SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 #if defined(LIBC_SCCS) && !defined(lint)
     41 #if 0
     42 static char sccsid[] = "@(#)glob.c	8.3 (Berkeley) 10/13/93";
     43 #else
     44 __RCSID("$NetBSD: glob.c,v 1.8 1997/10/21 00:56:55 fvdl Exp $");
     45 #endif
     46 #endif /* LIBC_SCCS and not lint */
     47 
     48 /*
     49  * glob(3) -- a superset of the one defined in POSIX 1003.2.
     50  *
     51  * The [!...] convention to negate a range is supported (SysV, Posix, ksh).
     52  *
     53  * Optional extra services, controlled by flags not defined by POSIX:
     54  *
     55  * GLOB_QUOTE:
     56  *	Escaping convention: \ inhibits any special meaning the following
     57  *	character might have (except \ at end of string is retained).
     58  * GLOB_MAGCHAR:
     59  *	Set in gl_flags if pattern contained a globbing character.
     60  * GLOB_NOMAGIC:
     61  *	Same as GLOB_NOCHECK, but it will only append pattern if it did
     62  *	not contain any magic characters.  [Used in csh style globbing]
     63  * GLOB_ALTDIRFUNC:
     64  *	Use alternately specified directory access functions.
     65  * GLOB_TILDE:
     66  *	expand ~user/foo to the /home/dir/of/user/foo
     67  * GLOB_BRACE:
     68  *	expand {1,2}{a,b} to 1a 1b 2a 2b
     69  * gl_matchc:
     70  *	Number of matches in the current invocation of glob.
     71  */
     72 
     73 #include "namespace.h"
     74 #include <sys/param.h>
     75 #include <sys/stat.h>
     76 
     77 #include <ctype.h>
     78 #include <dirent.h>
     79 #include <errno.h>
     80 #include <glob.h>
     81 #include <pwd.h>
     82 #include <stdio.h>
     83 #include <stdlib.h>
     84 #include <string.h>
     85 #include <unistd.h>
     86 
     87 #undef glob
     88 #undef globfree
     89 #undef fstat
     90 #undef lstat
     91 #undef stat
     92 
     93 #ifdef __weak_alias
     94 __weak_alias(glob,_glob);
     95 __weak_alias(globfree,_globfree);
     96 #endif
     97 
     98 #define	DOLLAR		'$'
     99 #define	DOT		'.'
    100 #define	EOS		'\0'
    101 #define	LBRACKET	'['
    102 #define	NOT		'!'
    103 #define	QUESTION	'?'
    104 #define	QUOTE		'\\'
    105 #define	RANGE		'-'
    106 #define	RBRACKET	']'
    107 #define	SEP		'/'
    108 #define	STAR		'*'
    109 #define	TILDE		'~'
    110 #define	UNDERSCORE	'_'
    111 #define	LBRACE		'{'
    112 #define	RBRACE		'}'
    113 #define	SLASH		'/'
    114 #define	COMMA		','
    115 
    116 #ifndef DEBUG
    117 
    118 #define	M_QUOTE		0x8000
    119 #define	M_PROTECT	0x4000
    120 #define	M_MASK		0xffff
    121 #define	M_ASCII		0x00ff
    122 
    123 typedef u_short Char;
    124 
    125 #else
    126 
    127 #define	M_QUOTE		0x80
    128 #define	M_PROTECT	0x40
    129 #define	M_MASK		0xff
    130 #define	M_ASCII		0x7f
    131 
    132 typedef char Char;
    133 
    134 #endif
    135 
    136 
    137 #define	CHAR(c)		((Char)((c)&M_ASCII))
    138 #define	META(c)		((Char)((c)|M_QUOTE))
    139 #define	M_ALL		META('*')
    140 #define	M_END		META(']')
    141 #define	M_NOT		META('!')
    142 #define	M_ONE		META('?')
    143 #define	M_RNG		META('-')
    144 #define	M_SET		META('[')
    145 #define	ismeta(c)	(((c)&M_QUOTE) != 0)
    146 
    147 
    148 static int	 compare __P((const void *, const void *));
    149 static void	 g_Ctoc __P((const Char *, char *));
    150 static int	 g_lstat __P((Char *, struct stat12 *, glob12_t *));
    151 static DIR	*g_opendir __P((Char *, glob12_t *));
    152 static Char	*g_strchr __P((Char *, int));
    153 #ifdef notdef
    154 static Char	*g_strcat __P((Char *, const Char *));
    155 #endif
    156 static int	 g_stat __P((Char *, struct stat12 *, glob12_t *));
    157 static int	 glob0 __P((const Char *, glob12_t *));
    158 static int	 glob1 __P((Char *, glob12_t *));
    159 static int	 glob2 __P((Char *, Char *, Char *, glob12_t *));
    160 static int	 glob3 __P((Char *, Char *, Char *, Char *, glob12_t *));
    161 static int	 globextend __P((const Char *, glob12_t *));
    162 static const Char *	 globtilde __P((const Char *, Char *, glob12_t *));
    163 static int	 globexp1 __P((const Char *, glob12_t *));
    164 static int	 globexp2 __P((const Char *, const Char *, glob12_t *, int *));
    165 static int	 match __P((Char *, Char *, Char *));
    166 #ifdef DEBUG
    167 static void	 qprintf __P((const char *, Char *));
    168 #endif
    169 
    170 int
    171 glob(pattern, flags, errfunc, pglob)
    172 	const char *pattern;
    173 	int flags, (*errfunc) __P((const char *, int));
    174 	glob12_t *pglob;
    175 {
    176 	const u_char *patnext;
    177 	int c;
    178 	Char *bufnext, *bufend, patbuf[MAXPATHLEN+1];
    179 
    180 	patnext = (u_char *) pattern;
    181 	if (!(flags & GLOB_APPEND)) {
    182 		pglob->gl_pathc = 0;
    183 		pglob->gl_pathv = NULL;
    184 		if (!(flags & GLOB_DOOFFS))
    185 			pglob->gl_offs = 0;
    186 	}
    187 	pglob->gl_flags = flags & ~GLOB_MAGCHAR;
    188 	pglob->gl_errfunc = errfunc;
    189 	pglob->gl_matchc = 0;
    190 
    191 	bufnext = patbuf;
    192 	bufend = bufnext + MAXPATHLEN;
    193 	if (flags & GLOB_QUOTE) {
    194 		/* Protect the quoted characters. */
    195 		while (bufnext < bufend && (c = *patnext++) != EOS)
    196 			if (c == QUOTE) {
    197 				if ((c = *patnext++) == EOS) {
    198 					c = QUOTE;
    199 					--patnext;
    200 				}
    201 				*bufnext++ = c | M_PROTECT;
    202 			}
    203 			else
    204 				*bufnext++ = c;
    205 	}
    206 	else
    207 	    while (bufnext < bufend && (c = *patnext++) != EOS)
    208 		    *bufnext++ = c;
    209 	*bufnext = EOS;
    210 
    211 	if (flags & GLOB_BRACE)
    212 	    return globexp1(patbuf, pglob);
    213 	else
    214 	    return glob0(patbuf, pglob);
    215 }
    216 
    217 /*
    218  * Expand recursively a glob {} pattern. When there is no more expansion
    219  * invoke the standard globbing routine to glob the rest of the magic
    220  * characters
    221  */
    222 static int globexp1(pattern, pglob)
    223 	const Char *pattern;
    224 	glob12_t *pglob;
    225 {
    226 	const Char* ptr = pattern;
    227 	int rv;
    228 
    229 	/* Protect a single {}, for find(1), like csh */
    230 	if (pattern[0] == LBRACE && pattern[1] == RBRACE && pattern[2] == EOS)
    231 		return glob0(pattern, pglob);
    232 
    233 	while ((ptr = (const Char *) g_strchr((Char *) ptr, LBRACE)) != NULL)
    234 		if (!globexp2(ptr, pattern, pglob, &rv))
    235 			return rv;
    236 
    237 	return glob0(pattern, pglob);
    238 }
    239 
    240 
    241 /*
    242  * Recursive brace globbing helper. Tries to expand a single brace.
    243  * If it succeeds then it invokes globexp1 with the new pattern.
    244  * If it fails then it tries to glob the rest of the pattern and returns.
    245  */
    246 static int globexp2(ptr, pattern, pglob, rv)
    247 	const Char *ptr, *pattern;
    248 	glob12_t *pglob;
    249 	int *rv;
    250 {
    251 	int     i;
    252 	Char   *lm, *ls;
    253 	const Char *pe, *pm, *pl;
    254 	Char    patbuf[MAXPATHLEN + 1];
    255 
    256 	/* copy part up to the brace */
    257 	for (lm = patbuf, pm = pattern; pm != ptr; *lm++ = *pm++)
    258 		continue;
    259 	ls = lm;
    260 
    261 	/* Find the balanced brace */
    262 	for (i = 0, pe = ++ptr; *pe; pe++)
    263 		if (*pe == LBRACKET) {
    264 			/* Ignore everything between [] */
    265 			for (pm = pe++; *pe != RBRACKET && *pe != EOS; pe++)
    266 				continue;
    267 			if (*pe == EOS) {
    268 				/*
    269 				 * We could not find a matching RBRACKET.
    270 				 * Ignore and just look for RBRACE
    271 				 */
    272 				pe = pm;
    273 			}
    274 		}
    275 		else if (*pe == LBRACE)
    276 			i++;
    277 		else if (*pe == RBRACE) {
    278 			if (i == 0)
    279 				break;
    280 			i--;
    281 		}
    282 
    283 	/* Non matching braces; just glob the pattern */
    284 	if (i != 0 || *pe == EOS) {
    285 		*rv = glob0(patbuf, pglob);
    286 		return 0;
    287 	}
    288 
    289 	for (i = 0, pl = pm = ptr; pm <= pe; pm++)
    290 		switch (*pm) {
    291 		case LBRACKET:
    292 			/* Ignore everything between [] */
    293 			for (pl = pm++; *pm != RBRACKET && *pm != EOS; pm++)
    294 				continue;
    295 			if (*pm == EOS) {
    296 				/*
    297 				 * We could not find a matching RBRACKET.
    298 				 * Ignore and just look for RBRACE
    299 				 */
    300 				pm = pl;
    301 			}
    302 			break;
    303 
    304 		case LBRACE:
    305 			i++;
    306 			break;
    307 
    308 		case RBRACE:
    309 			if (i) {
    310 			    i--;
    311 			    break;
    312 			}
    313 			/* FALLTHROUGH */
    314 		case COMMA:
    315 			if (i && *pm == COMMA)
    316 				break;
    317 			else {
    318 				/* Append the current string */
    319 				for (lm = ls; (pl < pm); *lm++ = *pl++)
    320 					continue;
    321 				/*
    322 				 * Append the rest of the pattern after the
    323 				 * closing brace
    324 				 */
    325 				for (pl = pe + 1; (*lm++ = *pl++) != EOS;)
    326 					continue;
    327 
    328 				/* Expand the current pattern */
    329 #ifdef DEBUG
    330 				qprintf("globexp2:", patbuf);
    331 #endif
    332 				*rv = globexp1(patbuf, pglob);
    333 
    334 				/* move after the comma, to the next string */
    335 				pl = pm + 1;
    336 			}
    337 			break;
    338 
    339 		default:
    340 			break;
    341 		}
    342 	*rv = 0;
    343 	return 0;
    344 }
    345 
    346 
    347 
    348 /*
    349  * expand tilde from the passwd file.
    350  */
    351 static const Char *
    352 globtilde(pattern, patbuf, pglob)
    353 	const Char *pattern;
    354 	Char *patbuf;
    355 	glob12_t *pglob;
    356 {
    357 	struct passwd *pwd;
    358 	char *h;
    359 	const Char *p;
    360 	Char *b;
    361 
    362 	if (*pattern != TILDE || !(pglob->gl_flags & GLOB_TILDE))
    363 		return pattern;
    364 
    365 	/* Copy up to the end of the string or / */
    366 	for (p = pattern + 1, h = (char *) patbuf; *p && *p != SLASH;
    367 	     *h++ = *p++)
    368 		continue;
    369 
    370 	*h = EOS;
    371 
    372 	if (((char *) patbuf)[0] == EOS) {
    373 		/*
    374 		 * handle a plain ~ or ~/ by expanding $HOME
    375 		 * first and then trying the password file
    376 		 */
    377 		if ((h = getenv("HOME")) == NULL) {
    378 			if ((pwd = getpwuid(getuid())) == NULL)
    379 				return pattern;
    380 			else
    381 				h = pwd->pw_dir;
    382 		}
    383 	}
    384 	else {
    385 		/*
    386 		 * Expand a ~user
    387 		 */
    388 		if ((pwd = getpwnam((char*) patbuf)) == NULL)
    389 			return pattern;
    390 		else
    391 			h = pwd->pw_dir;
    392 	}
    393 
    394 	/* Copy the home directory */
    395 	for (b = patbuf; *h; *b++ = *h++)
    396 		continue;
    397 
    398 	/* Append the rest of the pattern */
    399 	while ((*b++ = *p++) != EOS)
    400 		continue;
    401 
    402 	return patbuf;
    403 }
    404 
    405 
    406 /*
    407  * The main glob() routine: compiles the pattern (optionally processing
    408  * quotes), calls glob1() to do the real pattern matching, and finally
    409  * sorts the list (unless unsorted operation is requested).  Returns 0
    410  * if things went well, nonzero if errors occurred.  It is not an error
    411  * to find no matches.
    412  */
    413 static int
    414 glob0(pattern, pglob)
    415 	const Char *pattern;
    416 	glob12_t *pglob;
    417 {
    418 	const Char *qpatnext;
    419 	int c, err, oldpathc;
    420 	Char *bufnext, patbuf[MAXPATHLEN+1];
    421 
    422 	qpatnext = globtilde(pattern, patbuf, pglob);
    423 	oldpathc = pglob->gl_pathc;
    424 	bufnext = patbuf;
    425 
    426 	/* We don't need to check for buffer overflow any more. */
    427 	while ((c = *qpatnext++) != EOS) {
    428 		switch (c) {
    429 		case LBRACKET:
    430 			c = *qpatnext;
    431 			if (c == NOT)
    432 				++qpatnext;
    433 			if (*qpatnext == EOS ||
    434 			    g_strchr((Char *) qpatnext+1, RBRACKET) == NULL) {
    435 				*bufnext++ = LBRACKET;
    436 				if (c == NOT)
    437 					--qpatnext;
    438 				break;
    439 			}
    440 			*bufnext++ = M_SET;
    441 			if (c == NOT)
    442 				*bufnext++ = M_NOT;
    443 			c = *qpatnext++;
    444 			do {
    445 				*bufnext++ = CHAR(c);
    446 				if (*qpatnext == RANGE &&
    447 				    (c = qpatnext[1]) != RBRACKET) {
    448 					*bufnext++ = M_RNG;
    449 					*bufnext++ = CHAR(c);
    450 					qpatnext += 2;
    451 				}
    452 			} while ((c = *qpatnext++) != RBRACKET);
    453 			pglob->gl_flags |= GLOB_MAGCHAR;
    454 			*bufnext++ = M_END;
    455 			break;
    456 		case QUESTION:
    457 			pglob->gl_flags |= GLOB_MAGCHAR;
    458 			*bufnext++ = M_ONE;
    459 			break;
    460 		case STAR:
    461 			pglob->gl_flags |= GLOB_MAGCHAR;
    462 			/* collapse adjacent stars to one,
    463 			 * to avoid exponential behavior
    464 			 */
    465 			if (bufnext == patbuf || bufnext[-1] != M_ALL)
    466 			    *bufnext++ = M_ALL;
    467 			break;
    468 		default:
    469 			*bufnext++ = CHAR(c);
    470 			break;
    471 		}
    472 	}
    473 	*bufnext = EOS;
    474 #ifdef DEBUG
    475 	qprintf("glob0:", patbuf);
    476 #endif
    477 
    478 	if ((err = glob1(patbuf, pglob)) != 0)
    479 		return(err);
    480 
    481 	/*
    482 	 * If there was no match we are going to append the pattern
    483 	 * if GLOB_NOCHECK was specified or if GLOB_NOMAGIC was specified
    484 	 * and the pattern did not contain any magic characters
    485 	 * GLOB_NOMAGIC is there just for compatibility with csh.
    486 	 */
    487 	if (pglob->gl_pathc == oldpathc &&
    488 	    ((pglob->gl_flags & GLOB_NOCHECK) ||
    489 	      ((pglob->gl_flags & GLOB_NOMAGIC) &&
    490 	       !(pglob->gl_flags & GLOB_MAGCHAR))))
    491 		return(globextend(pattern, pglob));
    492 	else if (!(pglob->gl_flags & GLOB_NOSORT))
    493 		qsort(pglob->gl_pathv + pglob->gl_offs + oldpathc,
    494 		    pglob->gl_pathc - oldpathc, sizeof(char *), compare);
    495 	return(0);
    496 }
    497 
    498 static int
    499 compare(p, q)
    500 	const void *p, *q;
    501 {
    502 	return(strcmp(*(char **)p, *(char **)q));
    503 }
    504 
    505 static int
    506 glob1(pattern, pglob)
    507 	Char *pattern;
    508 	glob12_t *pglob;
    509 {
    510 	Char pathbuf[MAXPATHLEN+1];
    511 
    512 	/* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
    513 	if (*pattern == EOS)
    514 		return(0);
    515 	return(glob2(pathbuf, pathbuf, pattern, pglob));
    516 }
    517 
    518 /*
    519  * The functions glob2 and glob3 are mutually recursive; there is one level
    520  * of recursion for each segment in the pattern that contains one or more
    521  * meta characters.
    522  */
    523 static int
    524 glob2(pathbuf, pathend, pattern, pglob)
    525 	Char *pathbuf, *pathend, *pattern;
    526 	glob12_t *pglob;
    527 {
    528 	struct stat12 sb;
    529 	Char *p, *q;
    530 	int anymeta;
    531 
    532 	/*
    533 	 * Loop over pattern segments until end of pattern or until
    534 	 * segment with meta character found.
    535 	 */
    536 	for (anymeta = 0;;) {
    537 		if (*pattern == EOS) {		/* End of pattern? */
    538 			*pathend = EOS;
    539 			if (g_lstat(pathbuf, &sb, pglob))
    540 				return(0);
    541 
    542 			if (((pglob->gl_flags & GLOB_MARK) &&
    543 			    pathend[-1] != SEP) && (S_ISDIR(sb.st_mode)
    544 			    || (S_ISLNK(sb.st_mode) &&
    545 			    (g_stat(pathbuf, &sb, pglob) == 0) &&
    546 			    S_ISDIR(sb.st_mode)))) {
    547 				*pathend++ = SEP;
    548 				*pathend = EOS;
    549 			}
    550 			++pglob->gl_matchc;
    551 			return(globextend(pathbuf, pglob));
    552 		}
    553 
    554 		/* Find end of next segment, copy tentatively to pathend. */
    555 		q = pathend;
    556 		p = pattern;
    557 		while (*p != EOS && *p != SEP) {
    558 			if (ismeta(*p))
    559 				anymeta = 1;
    560 			*q++ = *p++;
    561 		}
    562 
    563 		if (!anymeta) {		/* No expansion, do next segment. */
    564 			pathend = q;
    565 			pattern = p;
    566 			while (*pattern == SEP)
    567 				*pathend++ = *pattern++;
    568 		} else			/* Need expansion, recurse. */
    569 			return(glob3(pathbuf, pathend, pattern, p, pglob));
    570 	}
    571 	/* NOTREACHED */
    572 }
    573 
    574 static int
    575 glob3(pathbuf, pathend, pattern, restpattern, pglob)
    576 	Char *pathbuf, *pathend, *pattern, *restpattern;
    577 	glob12_t *pglob;
    578 {
    579 	register struct dirent *dp;
    580 	DIR *dirp;
    581 	int err;
    582 	char buf[MAXPATHLEN];
    583 
    584 	/*
    585 	 * The readdirfunc declaration can't be prototyped, because it is
    586 	 * assigned, below, to two functions which are prototyped in glob.h
    587 	 * and dirent.h as taking pointers to differently typed opaque
    588 	 * structures.
    589 	 */
    590 	struct dirent *(*readdirfunc) __P((void *));
    591 
    592 	*pathend = EOS;
    593 	errno = 0;
    594 
    595 	if ((dirp = g_opendir(pathbuf, pglob)) == NULL) {
    596 		/* TODO: don't call for ENOENT or ENOTDIR? */
    597 		if (pglob->gl_errfunc) {
    598 			g_Ctoc(pathbuf, buf);
    599 			if (pglob->gl_errfunc(buf, errno) ||
    600 			    pglob->gl_flags & GLOB_ERR)
    601 				return (GLOB_ABEND);
    602 		}
    603 		return(0);
    604 	}
    605 
    606 	err = 0;
    607 
    608 	/* Search directory for matching names. */
    609 	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
    610 		readdirfunc = pglob->gl_readdir;
    611 	else
    612 		readdirfunc = (struct dirent *(*)__P((void *))) readdir;
    613 	while ((dp = (*readdirfunc)(dirp))) {
    614 		register u_char *sc;
    615 		register Char *dc;
    616 
    617 		/* Initial DOT must be matched literally. */
    618 		if (dp->d_name[0] == DOT && *pattern != DOT)
    619 			continue;
    620 		for (sc = (u_char *) dp->d_name, dc = pathend;
    621 		     (*dc++ = *sc++) != EOS;)
    622 			continue;
    623 		if (!match(pathend, pattern, restpattern)) {
    624 			*pathend = EOS;
    625 			continue;
    626 		}
    627 		err = glob2(pathbuf, --dc, restpattern, pglob);
    628 		if (err)
    629 			break;
    630 	}
    631 
    632 	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
    633 		(*pglob->gl_closedir)(dirp);
    634 	else
    635 		closedir(dirp);
    636 	return(err);
    637 }
    638 
    639 
    640 /*
    641  * Extend the gl_pathv member of a glob12_t structure to accomodate a new item,
    642  * add the new item, and update gl_pathc.
    643  *
    644  * This assumes the BSD realloc, which only copies the block when its size
    645  * crosses a power-of-two boundary; for v7 realloc, this would cause quadratic
    646  * behavior.
    647  *
    648  * Return 0 if new item added, error code if memory couldn't be allocated.
    649  *
    650  * Invariant of the glob12_t structure:
    651  *	Either gl_pathc is zero and gl_pathv is NULL; or gl_pathc > 0 and
    652  *	gl_pathv points to (gl_offs + gl_pathc + 1) items.
    653  */
    654 static int
    655 globextend(path, pglob)
    656 	const Char *path;
    657 	glob12_t *pglob;
    658 {
    659 	register char **pathv;
    660 	register int i;
    661 	u_int newsize;
    662 	char *copy;
    663 	const Char *p;
    664 
    665 	newsize = sizeof(*pathv) * (2 + pglob->gl_pathc + pglob->gl_offs);
    666 	pathv = pglob->gl_pathv ?
    667 		    realloc((char *)pglob->gl_pathv, newsize) :
    668 		    malloc(newsize);
    669 	if (pathv == NULL)
    670 		return(GLOB_NOSPACE);
    671 
    672 	if (pglob->gl_pathv == NULL && pglob->gl_offs > 0) {
    673 		/* first time around -- clear initial gl_offs items */
    674 		pathv += pglob->gl_offs;
    675 		for (i = pglob->gl_offs; --i >= 0; )
    676 			*--pathv = NULL;
    677 	}
    678 	pglob->gl_pathv = pathv;
    679 
    680 	for (p = path; *p++;)
    681 		continue;
    682 	if ((copy = malloc(p - path)) != NULL) {
    683 		g_Ctoc(path, copy);
    684 		pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;
    685 	}
    686 	pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;
    687 	return(copy == NULL ? GLOB_NOSPACE : 0);
    688 }
    689 
    690 
    691 /*
    692  * pattern matching function for filenames.  Each occurrence of the *
    693  * pattern causes a recursion level.
    694  */
    695 static int
    696 match(name, pat, patend)
    697 	register Char *name, *pat, *patend;
    698 {
    699 	int ok, negate_range;
    700 	Char c, k;
    701 
    702 	while (pat < patend) {
    703 		c = *pat++;
    704 		switch (c & M_MASK) {
    705 		case M_ALL:
    706 			if (pat == patend)
    707 				return(1);
    708 			do
    709 			    if (match(name, pat, patend))
    710 				    return(1);
    711 			while (*name++ != EOS);
    712 			return(0);
    713 		case M_ONE:
    714 			if (*name++ == EOS)
    715 				return(0);
    716 			break;
    717 		case M_SET:
    718 			ok = 0;
    719 			if ((k = *name++) == EOS)
    720 				return(0);
    721 			if ((negate_range = ((*pat & M_MASK) == M_NOT)) != EOS)
    722 				++pat;
    723 			while (((c = *pat++) & M_MASK) != M_END)
    724 				if ((*pat & M_MASK) == M_RNG) {
    725 					if (c <= k && k <= pat[1])
    726 						ok = 1;
    727 					pat += 2;
    728 				} else if (c == k)
    729 					ok = 1;
    730 			if (ok == negate_range)
    731 				return(0);
    732 			break;
    733 		default:
    734 			if (*name++ != c)
    735 				return(0);
    736 			break;
    737 		}
    738 	}
    739 	return(*name == EOS);
    740 }
    741 
    742 /* Free allocated data belonging to a glob12_t structure. */
    743 void
    744 globfree(pglob)
    745 	glob12_t *pglob;
    746 {
    747 	register int i;
    748 	register char **pp;
    749 
    750 	if (pglob->gl_pathv != NULL) {
    751 		pp = pglob->gl_pathv + pglob->gl_offs;
    752 		for (i = pglob->gl_pathc; i--; ++pp)
    753 			if (*pp)
    754 				free(*pp);
    755 		free(pglob->gl_pathv);
    756 	}
    757 }
    758 
    759 static DIR *
    760 g_opendir(str, pglob)
    761 	register Char *str;
    762 	glob12_t *pglob;
    763 {
    764 	char buf[MAXPATHLEN];
    765 
    766 	if (!*str)
    767 		strcpy(buf, ".");
    768 	else
    769 		g_Ctoc(str, buf);
    770 
    771 	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
    772 		return((*pglob->gl_opendir)(buf));
    773 
    774 	return(opendir(buf));
    775 }
    776 
    777 static int
    778 g_lstat(fn, sb, pglob)
    779 	register Char *fn;
    780 	struct stat12 *sb;
    781 	glob12_t *pglob;
    782 {
    783 	char buf[MAXPATHLEN];
    784 
    785 	g_Ctoc(fn, buf);
    786 	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
    787 		return((*pglob->gl_lstat)(buf, sb));
    788 	return(lstat(buf, sb));
    789 }
    790 
    791 static int
    792 g_stat(fn, sb, pglob)
    793 	register Char *fn;
    794 	struct stat12 *sb;
    795 	glob12_t *pglob;
    796 {
    797 	char buf[MAXPATHLEN];
    798 
    799 	g_Ctoc(fn, buf);
    800 	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
    801 		return((*pglob->gl_stat)(buf, sb));
    802 	return(stat(buf, sb));
    803 }
    804 
    805 static Char *
    806 g_strchr(str, ch)
    807 	Char *str;
    808 	int ch;
    809 {
    810 	do {
    811 		if (*str == ch)
    812 			return (str);
    813 	} while (*str++);
    814 	return (NULL);
    815 }
    816 
    817 #ifdef notdef
    818 static Char *
    819 g_strcat(dst, src)
    820 	Char *dst;
    821 	const Char* src;
    822 {
    823 	Char *sdst = dst;
    824 
    825 	while (*dst++)
    826 		continue;
    827 	--dst;
    828 	while((*dst++ = *src++) != EOS)
    829 	    continue;
    830 
    831 	return (sdst);
    832 }
    833 #endif
    834 
    835 static void
    836 g_Ctoc(str, buf)
    837 	register const Char *str;
    838 	char *buf;
    839 {
    840 	register char *dc;
    841 
    842 	for (dc = buf; (*dc++ = *str++) != EOS;)
    843 		continue;
    844 }
    845 
    846 #ifdef DEBUG
    847 static void
    848 qprintf(str, s)
    849 	const char *str;
    850 	register Char *s;
    851 {
    852 	register Char *p;
    853 
    854 	(void)printf("%s:\n", str);
    855 	for (p = s; *p; p++)
    856 		(void)printf("%c", CHAR(*p));
    857 	(void)printf("\n");
    858 	for (p = s; *p; p++)
    859 		(void)printf("%c", *p & M_PROTECT ? '"' : ' ');
    860 	(void)printf("\n");
    861 	for (p = s; *p; p++)
    862 		(void)printf("%c", ismeta(*p) ? '_' : ' ');
    863 	(void)printf("\n");
    864 }
    865 #endif
    866