/*      $NetBSD: fnmatch.c,v 1.26 2014/10/12 22:32:33 christos Exp $    */

/*
 * Copyright (c) 1989, 1993, 1994
 *      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. 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.
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)fnmatch.c   8.2 (Berkeley) 4/16/94";
#else
__RCSID("$NetBSD: fnmatch.c,v 1.26 2014/10/12 22:32:33 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

/*
 * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
 * Compares a filename or pathname to a pattern.
 */

#include "namespace.h"

#include <assert.h>
#include <ctype.h>
#include <fnmatch.h>
#include <string.h>

#ifdef __weak_alias
__weak_alias(fnmatch,_fnmatch)
#endif

#define EOS     '\0'

static inline int
foldcase(int ch, int flags)
{

        if ((flags & FNM_CASEFOLD) != 0 && isupper(ch))
                return tolower(ch);
        return ch;
}

#define FOLDCASE(ch, flags)     foldcase((unsigned char)(ch), (flags))

static const char *
rangematch(const char *pattern, int test, int flags)
{
        int negate, ok, need;
        char c, c2;

        _DIAGASSERT(pattern != NULL);

        /*
         * A bracket expression starting with an unquoted circumflex
         * character produces unspecified results (IEEE 1003.2-1992,
         * 3.13.2).  This implementation treats it like '!', for
         * consistency with the regular expression syntax.
         * J.T. Conklin (conklin@ngai.kaleida.com)
         */
        if ((negate = (*pattern == '!' || *pattern == '^')) != 0)
                ++pattern;
        
        need = 1;
        for (ok = 0; (c = FOLDCASE(*pattern++, flags)) != ']' || need;) {
                need = 0;
                if (c == '/')
                        return (void *)-1;
                if (c == '\\' && !(flags & FNM_NOESCAPE))
                        c = FOLDCASE(*pattern++, flags);
                if (c == EOS)
                        return NULL;
                if (*pattern == '-' 
                    && (c2 = FOLDCASE(*(pattern + 1), flags)) != EOS &&
                        c2 != ']') {
                        pattern += 2;
                        if (c2 == '\\' && !(flags & FNM_NOESCAPE))
                                c2 = FOLDCASE(*pattern++, flags);
                        if (c2 == EOS)
                                return NULL;
                        if (c <= test && test <= c2)
                                ok = 1;
                } else if (c == test)
                        ok = 1;
        }
        return ok == negate ? NULL : pattern;
}


static int
fnmatchx(const char *pattern, const char *string, int flags, size_t recursion)
{
        const char *stringstart, *r;
        char c, test;

        _DIAGASSERT(pattern != NULL);
        _DIAGASSERT(string != NULL);

        if (recursion-- == 0)
                return FNM_NORES;

        for (stringstart = string;;) {
                switch (c = FOLDCASE(*pattern++, flags)) {
                case EOS:
                        if ((flags & FNM_LEADING_DIR) && *string == '/')
                                return 0;
                        return *string == EOS ? 0 : FNM_NOMATCH;
                case '?':
                        if (*string == EOS)
                                return FNM_NOMATCH;
                        if (*string == '/' && (flags & FNM_PATHNAME))
                                return FNM_NOMATCH;
                        if (*string == '.' && (flags & FNM_PERIOD) &&
                            (string == stringstart ||
                            ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
                                return FNM_NOMATCH;
                        ++string;
                        break;
                case '*':
                        c = FOLDCASE(*pattern, flags);
                        /* Collapse multiple stars. */
                        while (c == '*')
                                c = FOLDCASE(*++pattern, flags);

                        if (*string == '.' && (flags & FNM_PERIOD) &&
                            (string == stringstart ||
                            ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
                                return FNM_NOMATCH;

                        /* Optimize for pattern with * at end or before /. */
                        if (c == EOS) {
                                if (flags & FNM_PATHNAME)
                                        return (flags & FNM_LEADING_DIR) ||
                                            strchr(string, '/') == NULL ?
                                            0 : FNM_NOMATCH;
                                else
                                        return 0;
                        } else if (c == '/' && flags & FNM_PATHNAME) {
                                if ((string = strchr(string, '/')) == NULL)
                                        return FNM_NOMATCH;
                                break;
                        }

                        /* General case, use recursion. */
                        while ((test = FOLDCASE(*string, flags)) != EOS) {
                                int e;
                                switch ((e = fnmatchx(pattern, string,
                                    flags & ~FNM_PERIOD, recursion))) {
                                case FNM_NOMATCH:
                                        break;
                                default:
                                        return e;
                                }
                                if (test == '/' && flags & FNM_PATHNAME)
                                        break;
                                ++string;
                        }
                        return FNM_NOMATCH;
                case '[':
                        if (*string == EOS)
                                return FNM_NOMATCH;
                        if (*string == '/' && flags & FNM_PATHNAME)
                                return FNM_NOMATCH;
                        if ((r = rangematch(pattern,
                            FOLDCASE(*string, flags), flags)) == NULL)
                                return FNM_NOMATCH;
                        if (r == (void *)-1) {
                                if (*string != '[')
                                        return FNM_NOMATCH;
                        } else
                                pattern = r;
                        ++string;
                        break;
                case '\\':
                        if (!(flags & FNM_NOESCAPE)) {
                                if ((c = FOLDCASE(*pattern++, flags)) == EOS) {
                                        c = '\0';
                                        --pattern;
                                }
                        }
                        /* FALLTHROUGH */
                default:
                        if (c != FOLDCASE(*string++, flags))
                                return FNM_NOMATCH;
                        break;
                }
        }
        /* NOTREACHED */
}

int
fnmatch(const char *pattern, const char *string, int flags)
{
        return fnmatchx(pattern, string, flags, 64);
}