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 #ifndef HAVE_DOS_BASED_FILE_SYSTEM
  54   return strcmp(s1, s2);
  55 #else
  56   for (;;)
  57     {
  58       int c1 = TOLOWER (*s1);
  59       int c2 = TOLOWER (*s2);
  60
  61       /* On DOS-based file systems, the '/' and the '\' are equivalent.  */
  62       if (c1 == '/')
  63         c1 = '\\';
  64       if (c2 == '/')
  65         c2 = '\\';
  66
  67       if (c1 != c2)
  68         return (c1 - c2);
  69
  70       if (c1 == '\0')
  71         return 0;
  72
  73       s1++;
  74       s2++;
  75     }
  76 #endif
  77 }
  78
  79 /*
  80
  81 @deftypefn Extension int filename_ncmp (const char *@var{s1}, const char *@var{s2}, size_t @var{n})
  82
  83 Return zero if the two file names @var{s1} and @var{s2} are equivalent
  84 in range @var{n}.
  85 If not equivalent, the returned value is similar to what @code{strncmp}
  86 would return.  In other words, it returns a negative value if @var{s1}
  87 is less than @var{s2}, or a positive value if @var{s2} is greater than
  88 @var{s2}.
  89
  90 This function does not normalize file names.  As a result, this function
  91 will treat filenames that are spelled differently as different even in
  92 the case when the two filenames point to the same underlying file.
  93 However, it does handle the fact that on DOS-like file systems, forward
  94 and backward slashes are equal.
  95
  96 @end deftypefn
  97
  98 */
  99
 100 int
 101 filename_ncmp (const char *s1, const char *s2, size_t n)
 102 {
 103 #ifndef HAVE_DOS_BASED_FILE_SYSTEM
 104   return strncmp(s1, s2, n);
 105 #else
 106   if (!n)
 107     return 0;
 108   for (; n > 0; --n)
 109   {
 110       int c1 = TOLOWER (*s1);
 111       int c2 = TOLOWER (*s2);
 112
 113       /* On DOS-based file systems, the '/' and the '\' are equivalent.  */
 114       if (c1 == '/')
 115         c1 = '\\';
 116       if (c2 == '/')
 117         c2 = '\\';
 118
 119       if (c1 == '\0' || c1 != c2)
 120         return (c1 - c2);
 121
 122       s1++;
 123       s2++;
 124   }
 125   return 0;
 126 #endif
 127 }