1 /* Copyright (C) 1996-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <wchar.h>
19 
20 #ifdef WMEMCMP
21 # define __wmemcmp WMEMCMP
22 #endif
23 
24 int
__wmemcmp(const wchar_t * s1,const wchar_t * s2,size_t n)25 __wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
26 {
27   wchar_t c1;
28   wchar_t c2;
29 
30   while (n >= 4)
31     {
32       c1 = s1[0];
33       c2 = s2[0];
34       if (c1 - c2 != 0)
35 	return c1 > c2 ? 1 : -1;
36       c1 = s1[1];
37       c2 = s2[1];
38       if (c1 - c2 != 0)
39 	return c1 > c2 ? 1 : -1;
40       c1 = s1[2];
41       c2 = s2[2];
42       if (c1 - c2 != 0)
43 	return c1 > c2 ? 1 : -1;
44       c1 = s1[3];
45       c2 = s2[3];
46       if (c1 - c2 != 0)
47 	return c1 > c2 ? 1 : -1;
48       s1 += 4;
49       s2 += 4;
50       n -= 4;
51     }
52 
53   if (n > 0)
54     {
55       c1 = s1[0];
56       c2 = s2[0];
57       if (c1 - c2 != 0)
58 	return c1 > c2 ? 1 : -1;
59       ++s1;
60       ++s2;
61       --n;
62     }
63   if (n > 0)
64     {
65       c1 = s1[0];
66       c2 = s2[0];
67       if (c1 - c2 != 0)
68 	return c1 > c2 ? 1 : -1;
69       ++s1;
70       ++s2;
71       --n;
72     }
73   if (n > 0)
74     {
75       c1 = s1[0];
76       c2 = s2[0];
77       if (c1 - c2 != 0)
78 	return c1 > c2 ? 1 : -1;
79     }
80 
81   return 0;
82 }
83 #ifndef WMEMCMP
84 weak_alias (__wmemcmp, wmemcmp)
85 #endif
86