1 /*
2 FUNCTION
3 <<wcsncmp>>---compare part of two wide-character strings
4
5 SYNOPSIS
6 #include <wchar.h>
7 int wcsncmp(const wchar_t *<[s1]>, const wchar_t *<[s2]>, size_t <[n]>);
8
9 DESCRIPTION
10 The <<wcsncmp>> function compares not more than <[n]> wide-character
11 codes (wide-character codes that follow a null wide-character code are
12 not compared) from the array pointed to by <[s1]> to the array pointed
13 to by <[s2]>.
14
15 The sign of a non-zero return value is determined by the sign of the
16 difference between the values of the first pair of wide-character codes
17 that differ in the objects being compared.
18
19 RETURNS
20 Upon successful completion, <<wcsncmp>> returns an integer greater than,
21 equal to or less than 0, if the possibly null-terminated array pointed
22 to by <[s1]> is greater than, equal to or less than the possibly
23 null-terminated array pointed to by <[s2]> respectively.
24
25 PORTABILITY
26 <<wcsncmp>> is ISO/IEC 9899/AMD1:1995 (ISO C).
27
28 No supporting OS subroutines are required.
29 */
30
31 /* $NetBSD$ */
32
33 /*
34 * Copyright (c) 1989, 1993
35 * The Regents of the University of California. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 */
61
62 #include <_ansi.h>
63 #include <wchar.h>
64
65 int
wcsncmp(const wchar_t * s1,const wchar_t * s2,size_t n)66 wcsncmp (const wchar_t * s1,
67 const wchar_t * s2,
68 size_t n)
69 {
70
71 if (n == 0)
72 return (0);
73 do
74 {
75 if (*s1 != *s2++)
76 {
77 return (*s1 < *--s2 ? -1 : 1);
78 }
79 if (*s1++ == 0)
80 break;
81 }
82 while (--n != 0);
83 return (0);
84 }
85
