glob.c

早期freebsd实现

/*
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Guido van Rossum.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)glob.c	8.3 (Berkeley) 10/13/93";
#endif /* LIBC_SCCS and not lint */

/*
 * glob(3) -- a superset of the one defined in POSIX 1003.2.
 *
 * The [!...] convention to negate a range is supported (SysV, Posix, ksh).
 *
 * Optional extra services, controlled by flags not defined by POSIX:
 *
 * GLOB_QUOTE:
 *	Escaping convention: \ inhibits any special meaning the following
 *	character might have (except \ at end of string is retained).
 * GLOB_MAGCHAR:
 *	Set in gl_flags if pattern contained a globbing character.
 * GLOB_NOMAGIC:
 *	Same as GLOB_NOCHECK, but it will only append pattern if it did
 *	not contain any magic characters.  [Used in csh style globbing]
 * GLOB_ALTDIRFUNC:
 *	Use alternately specified directory access functions.
 * GLOB_TILDE:
 *	expand ~user/foo to the /home/dir/of/user/foo
 * GLOB_BRACE:
 *	expand {1,2}{a,b} to 1a 1b 2a 2b 
 * gl_matchc:
 *	Number of matches in the current invocation of glob.
 */

#include <sys/param.h>
#include <sys/stat.h>

#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <glob.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define	DOLLAR		'$'
#define	DOT		'.'
#define	EOS		'\0'
#define	LBRACKET	'['
#define	NOT		'!'
#define	QUESTION	'?'
#define	QUOTE		'\\'
#define	RANGE		'-'
#define	RBRACKET	']'
#define	SEP		'/'
#define	STAR		'*'
#define	TILDE		'~'
#define	UNDERSCORE	'_'
#define	LBRACE		'{'
#define	RBRACE		'}'
#define	SLASH		'/'
#define	COMMA		','

#ifndef DEBUG

#define	M_QUOTE		0x8000
#define	M_PROTECT	0x4000
#define	M_MASK		0xffff
#define	M_ASCII		0x00ff

typedef u_short Char;

#else

#define	M_QUOTE		0x80
#define	M_PROTECT	0x40
#define	M_MASK		0xff
#define	M_ASCII		0x7f

typedef char Char;

#endif


#define	CHAR(c)		((Char)((c)&M_ASCII))
#define	META(c)		((Char)((c)|M_QUOTE))
#define	M_ALL		META('*')
#define	M_END		META(']')
#define	M_NOT		META('!')
#define	M_ONE		META('?')
#define	M_RNG		META('-')
#define	M_SET		META('[')
#define	ismeta(c)	(((c)&M_QUOTE) != 0)


static int	 compare __P((const void *, const void *));
static void	 g_Ctoc __P((const Char *, char *));
static int	 g_lstat __P((Char *, struct stat *, glob_t *));
static DIR	*g_opendir __P((Char *, glob_t *));
static Char	*g_strchr __P((Char *, int));
#ifdef notdef
static Char	*g_strcat __P((Char *, const Char *));
#endif
static int	 g_stat __P((Char *, struct stat *, glob_t *));
static int	 glob0 __P((const Char *, glob_t *));
static int	 glob1 __P((Char *, glob_t *));
static int	 glob2 __P((Char *, Char *, Char *, glob_t *));
static int	 glob3 __P((Char *, Char *, Char *, Char *, glob_t *));
static int	 globextend __P((const Char *, glob_t *));
static const Char *	 globtilde __P((const Char *, Char *, glob_t *));
static int	 globexp1 __P((const Char *, glob_t *));
static int	 globexp2 __P((const Char *, const Char *, glob_t *, int *));
static int	 match __P((Char *, Char *, Char *));
#ifdef DEBUG
static void	 qprintf __P((const char *, Char *));
#endif

int
glob(pattern, flags, errfunc, pglob)
	const char *pattern;
	int flags, (*errfunc) __P((const char *, int));
	glob_t *pglob;
{
	const u_char *patnext;
	int c;
	Char *bufnext, *bufend, patbuf[MAXPATHLEN+1];

	patnext = (u_char *) pattern;
	if (!(flags & GLOB_APPEND)) {
		pglob->gl_pathc = 0;
		pglob->gl_pathv = NULL;
		if (!(flags & GLOB_DOOFFS))
			pglob->gl_offs = 0;
	}
	pglob->gl_flags = flags & ~GLOB_MAGCHAR;
	pglob->gl_errfunc = errfunc;
	pglob->gl_matchc = 0;

	bufnext = patbuf;
	bufend = bufnext + MAXPATHLEN;
	if (flags & GLOB_QUOTE) {
		/* Protect the quoted characters. */
		while (bufnext < bufend && (c = *patnext++) != EOS) 
			if (c == QUOTE) {
				if ((c = *patnext++) == EOS) {
					c = QUOTE;
					--patnext;
				}
				*bufnext++ = c | M_PROTECT;
			}
			else
				*bufnext++ = c;
	}
	else 
	    while (bufnext < bufend && (c = *patnext++) != EOS) 
		    *bufnext++ = c;
	*bufnext = EOS;

	if (flags & GLOB_BRACE)
	    return globexp1(patbuf, pglob);
	else
	    return glob0(patbuf, pglob);
}

/*
 * Expand recursively a glob {} pattern. When there is no more expansion
 * invoke the standard globbing routine to glob the rest of the magic
 * characters
 */
static int globexp1(pattern, pglob)
	const Char *pattern;
	glob_t *pglob;
{
	const Char* ptr = pattern;
	int rv;

	/* Protect a single {}, for find(1), like csh */
	if (pattern[0] == LBRACE && pattern[1] == RBRACE && pattern[2] == EOS)
		return glob0(pattern, pglob);

	while ((ptr = (const Char *) g_strchr((Char *) ptr, LBRACE)) != NULL)
		if (!globexp2(ptr, pattern, pglob, &rv))
			return rv;

	return glob0(pattern, pglob);
}


/*
 * Recursive brace globbing helper. Tries to expand a single brace.
 * If it succeeds then it invokes globexp1 with the new pattern.
 * If it fails then it tries to glob the rest of the pattern and returns.
 */
static int globexp2(ptr, pattern, pglob, rv)
	const Char *ptr, *pattern;
	glob_t *pglob;
	int *rv;
{
	int     i;
	Char   *lm, *ls;
	const Char *pe, *pm, *pl;
	Char    patbuf[MAXPATHLEN + 1];

	/* copy part up to the brace */
	for (lm = patbuf, pm = pattern; pm != ptr; *lm++ = *pm++)
		continue;
	ls = lm;

	/* Find the balanced brace */
	for (i = 0, pe = ++ptr; *pe; pe++)
		if (*pe == LBRACKET) {
			/* Ignore everything between [] */
			for (pm = pe++; *pe != RBRACKET && *pe != EOS; pe++)
				continue;
			if (*pe == EOS) {
				/* 
				 * We could not find a matching RBRACKET.
				 * Ignore and just look for RBRACE
				 */
				pe = pm;
			}
		}
		else if (*pe == LBRACE)
			i++;
		else if (*pe == RBRACE) {
			if (i == 0)
				break;
			i--;
		}

	/* Non matching braces; just glob the pattern */
	if (i != 0 || *pe == EOS) {
		*rv = glob0(patbuf, pglob);
		return 0;
	}

	for (i = 0, pl = pm = ptr; pm <= pe; pm++)
		switch (*pm) {
		case LBRACKET:
			/* Ignore everything between [] */
			for (pl = pm++; *pm != RBRACKET && *pm != EOS; pm++)
				continue;
			if (*pm == EOS) {
				/* 
				 * We could not find a matching RBRACKET.
				 * Ignore and just look for RBRACE
				 */
				pm = pl;
			}
			break;

		case LBRACE:
			i++;
			break;

		case RBRACE:
			if (i) {
			    i--;
			    break;
			}
			/* FALLTHROUGH */
		case COMMA:
			if (i && *pm == COMMA)
				break;
			else {
				/* Append the current string */
				for (lm = ls; (pl < pm); *lm++ = *pl++)
					continue;
				/* 
				 * Append the rest of the pattern after the
				 * closing brace
				 */
				for (pl = pe + 1; (*lm++ = *pl++) != EOS;)
					continue;

				/* Expand the current pattern */
#ifdef DEBUG
				qprintf("globexp2:", patbuf);
#endif
				*rv = globexp1(patbuf, pglob);

				/* move after the comma, to the next string */
				pl = pm + 1;
			}
			break;

		default:
			break;
		}
	*rv = 0;
	return 0;
}



/*
 * expand tilde from the passwd file.
 */
static const Char *
globtilde(pattern, patbuf, pglob)
	const Char *pattern;
	Char *patbuf;
	glob_t *pglob;
{
	struct passwd *pwd;
	char *h;
	const Char *p;
	Char *b;

	if (*pattern != TILDE || !(pglob->gl_flags & GLOB_TILDE))
		return pattern;

	/* Copy up to the end of the string or / */
	for (p = pattern + 1, h = (char *) patbuf; *p && *p != SLASH; 
	     *h++ = *p++)
		continue;

	*h = EOS;

	if (((char *) patbuf)[0] == EOS) {
		/* 
		 * handle a plain ~ or ~/ by expanding $HOME 
		 * first and then trying the password file
		 */
		if ((h = getenv("HOME")) == NULL) {
			if ((pwd = getpwuid(getuid())) == NULL)
				return pattern;
			else
				h = pwd->pw_dir;
		}
	}
	else {
		/*
		 * Expand a ~user
		 */
		if ((pwd = getpwnam((char*) patbuf)) == NULL)
			return pattern;
		else
			h = pwd->pw_dir;
	}

	/* Copy the home directory */
	for (b = patbuf; *h; *b++ = *h++)
		continue;
	
	/* Append the rest of the pattern */
	while ((*b++ = *p++) != EOS)
		continue;

	return patbuf;
}
	

/*
 * The main glob() routine: compiles the pattern (optionally processing
 * quotes), calls glob1() to do the real pattern matching, and finally
 * sorts the list (unless unsorted operation is requested).  Returns 0
 * if things went well, nonzero if errors occurred.  It is not an error
 * to find no matches.
 */
static int
glob0(pattern, pglob)
	const Char *pattern;
	glob_t *pglob;
{
	const Char *qpatnext;
	int c, err, oldpathc;
	Char *bufnext, patbuf[MAXPATHLEN+1];

	qpatnext = globtilde(pattern, patbuf, pglob);
	oldpathc = pglob->gl_pathc;
	bufnext = patbuf;

	/* We don't need to check for buffer overflow any more. */
	while ((c = *qpatnext++) != EOS) {
		switch (c) {
		case LBRACKET:
			c = *qpatnext;
			if (c == NOT)
				++qpatnext;
			if (*qpatnext == EOS ||
			    g_strchr((Char *) qpatnext+1, RBRACKET) == NULL) {
				*bufnext++ = LBRACKET;
				if (c == NOT)
					--qpatnext;
				break;
			}
			*bufnext++ = M_SET;
			if (c == NOT)
				*bufnext++ = M_NOT;
			c = *qpatnext++;