xref: /dragonfly/contrib/grep/lib/c-strncasecmp.c (revision 6e278935)
1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* c-strncasecmp.c -- case insensitive string comparator in C locale
4    Copyright (C) 1998-1999, 2005-2006, 2009-2011 Free Software Foundation, Inc.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3, or (at your option)
9    any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software Foundation,
18    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
19 
20 #include <config.h>
21 
22 /* Specification.  */
23 #include "c-strcase.h"
24 
25 #include <limits.h>
26 
27 #include "c-ctype.h"
28 
29 int
30 c_strncasecmp (const char *s1, const char *s2, size_t n)
31 {
32   register const unsigned char *p1 = (const unsigned char *) s1;
33   register const unsigned char *p2 = (const unsigned char *) s2;
34   unsigned char c1, c2;
35 
36   if (p1 == p2 || n == 0)
37     return 0;
38 
39   do
40     {
41       c1 = c_tolower (*p1);
42       c2 = c_tolower (*p2);
43 
44       if (--n == 0 || c1 == '\0')
45         break;
46 
47       ++p1;
48       ++p2;
49     }
50   while (c1 == c2);
51 
52   if (UCHAR_MAX <= INT_MAX)
53     return c1 - c2;
54   else
55     /* On machines where 'char' and 'int' are types of the same size, the
56        difference of two 'unsigned char' values - including the sign bit -
57        doesn't fit in an 'int'.  */
58     return (c1 > c2 ? 1 : c1 < c2 ? -1 : 0);
59 }
60