sys/libkern/fnmatch.c

   1 /*
   2  * Copyright (c) 1989, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Guido van Rossum.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/sys/libkern/fnmatch.c,v 1.17 2003/06/11 05:23:04 obrien Exp $
  33  * $DragonFly: src/sys/libkern/fnmatch.c,v 1.3 2006/12/13 21:58:51 dillon Exp $
  34  */
  35
  36 /*
  37  * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
  38  * Compares a filename or pathname to a pattern.
  39  */
  40
  41 #include <sys/param.h>
  42 #include <sys/ctype.h>
  43 #include <sys/libkern.h>
  44
  45 #define EOS     '\0'
  46
  47 #define RANGE_MATCH     1
  48 #define RANGE_NOMATCH   0
  49 #define RANGE_ERROR     (-1)
  50
  51 #define MAXNEST         20
  52
  53 static int rangematch(const char *, char, int, char **);
  54
  55 int
  56 _kfnmatch(const char *pattern, const char *string, int flags, int nesting)
  57 {
  58         const char *stringstart;
  59         char *newp;
  60         char c, test;
  61
  62         if (nesting == MAXNEST)
  63                 return (FNM_NOMATCH);
  64
  65         for (stringstart = string;;) {
  66                 switch (c = *pattern++) {
  67                 case EOS:
  68                         if ((flags & FNM_LEADING_DIR) && *string == '/')
  69                                 return (0);
  70                         return (*string == EOS ? 0 : FNM_NOMATCH);
  71                 case '?':
  72                         if (*string == EOS)
  73                                 return (FNM_NOMATCH);
  74                         if (*string == '/' && (flags & FNM_PATHNAME))
  75                                 return (FNM_NOMATCH);
  76                         if (*string == '.' && (flags & FNM_PERIOD) &&
  77                             (string == stringstart ||
  78                             ((flags & FNM_PATHNAME) && *(string - 1) == '/'))) {
  79                                 return (FNM_NOMATCH);
  80                         }
  81                         ++string;
  82                         break;
  83                 case '*':
  84                         c = *pattern;
  85                         /* Collapse multiple stars. */
  86                         while (c == '*')
  87                                 c = *++pattern;
  88
  89                         if (*string == '.' && (flags & FNM_PERIOD) &&
  90                             (string == stringstart ||
  91                             ((flags & FNM_PATHNAME) && *(string - 1) == '/'))) {
  92                                 return (FNM_NOMATCH);
  93                         }
  94
  95                         /* Optimize for pattern with * at end or before /. */
  96                         if (c == EOS) {
  97                                 if (flags & FNM_PATHNAME) {
  98                                         return ((flags & FNM_LEADING_DIR) ||
  99                                             index(string, '/') == NULL ?
 100                                             0 : FNM_NOMATCH);
 101                                 } else {
 102                                         return (0);
 103                                 }
 104                         } else if (c == '/' && flags & FNM_PATHNAME) {
 105                                 if ((string = index(string, '/')) == NULL)
 106                                         return (FNM_NOMATCH);
 107                                 break;
 108                         }
 109
 110                         /* General case, use recursion. */
 111                         while ((test = *string) != EOS) {
 112                                 if (!_kfnmatch(pattern, string, flags & ~FNM_PERIOD, nesting + 1))
 113                                         return (0);
 114                                 if (test == '/' && flags & FNM_PATHNAME)
 115                                         break;
 116                                 ++string;
 117                         }
 118                         return (FNM_NOMATCH);
 119                 case '[':
 120                         if (*string == EOS)
 121                                 return (FNM_NOMATCH);
 122                         if (*string == '/' && (flags & FNM_PATHNAME))
 123                                 return (FNM_NOMATCH);
 124                         if (*string == '.' && (flags & FNM_PERIOD) &&
 125                             (string == stringstart ||
 126                             ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
 127                                 return (FNM_NOMATCH);
 128
 129                         switch (rangematch(pattern, *string, flags, &newp)) {
 130                         case RANGE_ERROR:
 131                                 goto norm;
 132                         case RANGE_MATCH:
 133                                 pattern = newp;
 134                                 break;
 135                         case RANGE_NOMATCH:
 136                                 return (FNM_NOMATCH);
 137                         }
 138                         ++string;
 139                         break;
 140                 case '\\':
 141                         if (!(flags & FNM_NOESCAPE)) {
 142                                 if ((c = *pattern++) == EOS) {
 143                                         c = '\\';
 144                                         --pattern;
 145                                 }
 146                         }
 147                         /* FALLTHROUGH */
 148                 default:
 149                 norm:
 150                         if (c == *string) {
 151                                 ;
 152                         } else if ((flags & FNM_CASEFOLD) &&
 153                                  (tolower((unsigned char)c) ==
 154                                   tolower((unsigned char)*string))) {
 155                                 ;
 156                         } else {
 157                                 return (FNM_NOMATCH);
 158                         }
 159                         string++;
 160                         break;
 161                 }
 162         }
 163         /* NOTREACHED */
 164 }
 165
 166 static int
 167 rangematch(const char *pattern, char test, int flags, char **newp)
 168 {
 169         int negate, ok;
 170         char c, c2;
 171
 172         /*
 173          * A bracket expression starting with an unquoted circumflex
 174          * character produces unspecified results (IEEE 1003.2-1992,
 175          * 3.13.2).  This implementation treats it like '!', for
 176          * consistency with the regular expression syntax.
 177          * J.T. Conklin (conklin@ngai.kaleida.com)
 178          */
 179         if ((negate = (*pattern == '!' || *pattern == '^')) != 0)
 180                 ++pattern;
 181
 182         if (flags & FNM_CASEFOLD)
 183                 test = tolower((unsigned char)test);
 184
 185         /*
 186          * A right bracket shall lose its special meaning and represent
 187          * itself in a bracket expression if it occurs first in the list.
 188          * -- POSIX.2 2.8.3.2
 189          */
 190         ok = 0;
 191         c = *pattern++;
 192         do {
 193                 if (c == '\\' && !(flags & FNM_NOESCAPE))
 194                         c = *pattern++;
 195                 if (c == EOS)
 196                         return (RANGE_ERROR);
 197
 198                 if (c == '/' && (flags & FNM_PATHNAME))
 199                         return (RANGE_NOMATCH);
 200
 201                 if (flags & FNM_CASEFOLD)
 202                         c = tolower((unsigned char)c);
 203
 204                 if (*pattern == '-'
 205                     && (c2 = *(pattern+1)) != EOS && c2 != ']') {
 206                         pattern += 2;
 207                         if (c2 == '\\' && !(flags & FNM_NOESCAPE))
 208                                 c2 = *pattern++;
 209                         if (c2 == EOS)
 210                                 return (RANGE_ERROR);
 211
 212                         if (flags & FNM_CASEFOLD)
 213                                 c2 = tolower((unsigned char)c2);
 214
 215                         if (c <= test && test <= c2)
 216                                 ok = 1;
 217                 } else if (c == test) {
 218                         ok = 1;
 219                 }
 220         } while ((c = *pattern++) != ']');
 221
 222         *newp = (char *)(uintptr_t)pattern;
 223         return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
 224 }
 225