libiberty/filename_cmp.c

   1 /* File name comparison routine.
   2
   3    Copyright (C) 2007 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software Foundation,
  17    Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 #include "config.h"
  21 #endif
  22
  23 #ifdef HAVE_STRING_H
  24 #include <string.h>
  25 #endif
  26
  27 #include "filenames.h"
  28 #include "safe-ctype.h"
  29
  30 /*
  31
  32 @deftypefn Extension int filename_cmp (const char *@var{s1}, const char *@var{s2})
  33
  34 Return zero if the two file names @var{s1} and @var{s2} are equivalent.
  35 If not equivalent, the returned value is similar to what @code{strcmp}
  36 would return.  In other words, it returns a negative value if @var{s1}
  37 is less than @var{s2}, or a positive value if @var{s2} is greater than
  38 @var{s2}.
  39
  40 This function does not normalize file names.  As a result, this function
  41 will treat filenames that are spelled differently as different even in
  42 the case when the two filenames point to the same underlying file.
  43 However, it does handle the fact that on DOS-like file systems, forward
  44 and backward slashes are equal.
  45
  46 @end deftypefn
  47
  48 */
  49
  50 int
  51 filename_cmp (const char *s1, const char *s2)
  52 {
  53 #if !defined(HAVE_DOS_BASED_FILE_SYSTEM) \
  54     && !defined(HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
  55   return strcmp(s1, s2);
  56 #else
  57   for (;;)
  58     {
  59       int c1 = *s1;
  60       int c2 = *s2;
  61
  62 #if defined (HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
  63       c1 = TOLOWER (c1);
  64       c2 = TOLOWER (c2);
  65 #endif
  66
  67 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
  68       /* On DOS-based file systems, the '/' and the '\' are equivalent.  */
  69       if (c1 == '/')
  70         c1 = '\\';
  71       if (c2 == '/')
  72         c2 = '\\';
  73 #endif
  74
  75       if (c1 != c2)
  76         return (c1 - c2);
  77
  78       if (c1 == '\0')
  79         return 0;
  80
  81       s1++;
  82       s2++;
  83     }
  84 #endif
  85 }
  86
  87 /*
  88
  89 @deftypefn Extension int filename_ncmp (const char *@var{s1}, const char *@var{s2}, size_t @var{n})
  90
  91 Return zero if the two file names @var{s1} and @var{s2} are equivalent
  92 in range @var{n}.
  93 If not equivalent, the returned value is similar to what @code{strncmp}
  94 would return.  In other words, it returns a negative value if @var{s1}
  95 is less than @var{s2}, or a positive value if @var{s2} is greater than
  96 @var{s2}.
  97
  98 This function does not normalize file names.  As a result, this function
  99 will treat filenames that are spelled differently as different even in
 100 the case when the two filenames point to the same underlying file.
 101 However, it does handle the fact that on DOS-like file systems, forward
 102 and backward slashes are equal.
 103
 104 @end deftypefn
 105
 106 */
 107
 108 int
 109 filename_ncmp (const char *s1, const char *s2, size_t n)
 110 {
 111 #if !defined(HAVE_DOS_BASED_FILE_SYSTEM) \
 112     && !defined(HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
 113   return strncmp(s1, s2, n);
 114 #else
 115   if (!n)
 116     return 0;
 117   for (; n > 0; --n)
 118   {
 119       int c1 = *s1;
 120       int c2 = *s2;
 121
 122 #if defined (HAVE_CASE_INSENSITIVE_FILE_SYSTEM)
 123       c1 = TOLOWER (c1);
 124       c2 = TOLOWER (c2);
 125 #endif
 126
 127 #if defined (HAVE_DOS_BASED_FILE_SYSTEM)
 128       /* On DOS-based file systems, the '/' and the '\' are equivalent.  */
 129       if (c1 == '/')
 130         c1 = '\\';
 131       if (c2 == '/')
 132         c2 = '\\';
 133 #endif
 134
 135       if (c1 == '\0' || c1 != c2)
 136         return (c1 - c2);
 137
 138       s1++;
 139       s2++;
 140   }
 141   return 0;
 142 #endif
 143 }
 144
 145 /*
 146
 147 @deftypefn Extension hashval_t filename_hash (const void *@var{s})
 148
 149 Return the hash value for file name @var{s} that will be compared
 150 using filename_cmp.
 151 This function is for use with hashtab.c hash tables.
 152
 153 @end deftypefn
 154
 155 */
 156
 157 hashval_t
 158 filename_hash (const void *s)
 159 {
 160   /* The cast is for -Wc++-compat.  */
 161   const unsigned char *str = (const unsigned char *) s;
 162   hashval_t r = 0;
 163   unsigned char c;
 164
 165   while ((c = *str++) != 0)
 166     {
 167       if (c == '\\')
 168         c = '/';
 169       c = TOLOWER (c);
 170       r = r * 67 + c - 113;
 171     }
 172
 173   return r;
 174 }
 175
 176 /*
 177
 178 @deftypefn Extension int filename_eq (const void *@var{s1}, const void *@var{s2})
 179
 180 Return non-zero if file names @var{s1} and @var{s2} are equivalent.
 181 This function is for use with hashtab.c hash tables.
 182
 183 @end deftypefn
 184
 185 */
 186
 187 int
 188 filename_eq (const void *s1, const void *s2)
 189 {
 190   /* The casts are for -Wc++-compat.  */
 191   return filename_cmp ((const char *) s1, (const char *) s2) == 0;
 192 }