blob: d5fa66692dbb0b37101f22d707fbad5ca4b37b3e (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
/**
* slibc — Yet another C library
* Copyright © 2015 Mattias Andrée (maandree@member.fsf.org)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <string.h>
#include <ctype.h>
/**
* Compare two strings alphabetically in a case insensitive manner.
* Be aware, only ASCII characters are case insensitive, non-ASCII
* characters are case sensitive.
*
* @etymology (Str)ing-function: (n)-bytes, (case) insensitive (c)o(mp)arison.
*
* @param a A negative value is returned if this is the lesser.
* @param b A positive value is returned if this is the lesser.
* @param length The maximum number of characters to compare.
* @return Zero is returned if `a` and `b` are equal, otherwise,
* see the specifications for `a` and `b`.
*
* @since Always.
*/
int strncasecmp(const char* a, const char* b, size_t length)
{
int c1, c2;
for (; length--; a++, b++)
if (*a != *b)
{
c1 = isalpha(*a) ? tolower(*a) : (int)*a;
c2 = isalpha(*b) ? tolower(*b) : (int)*b;
if ((c1 -= c2))
return c1;
}
else if (!*a && !*b) return 0;
else if (!*a) return -1;
else if (!*b) return +1;
return 0;
}
|
