aboutsummaryrefslogtreecommitdiff
path: root/arch/all/core/src/string/strchr.c
blob: 9f0e11bd50edf46a8ec26e9c63f82411f0a60c4c (plain)
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
/* ****************************************************************************
 * string/strchr.c -- Look for a character in a string.
 *
 * Copyright (C) 2017 Thomas "Cakeisalie5" Touhey <thomas@touhey.fr>
 *
 * This file is part of the 'all/core' module in libcarrot, an experimental
 * modular libc project.
 *
 * This file is free software: you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation, either version 3 of the License, or (at your option)
 * any later version.
 *
 * This file 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 Lesser General Lesser Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this file. If not, see <http://www.gnu.org/licenses/>.
 * ************************************************************************* */
#include <string.h>

/**
 *	strchr:
 *	Look for the first occurrence of a character in a string.
 *
 *	@arg	s		the string.
 *	@arg	c		the character.
 *	@return			the result (NULL if not found).
 */

char *strchr(const char *s, int c)
{
	for (; *s && *s != c; s++);
	return (*s == c ? (char*)s : NULL);
}

/**
 *	strrchr:
 *	Look for the last occurrence of a character in a string.
 *
 *	@arg	s		the string.
 *	@arg	c		the character.
 *	@return			the result (NULL if not found).
 */

char *strrchr(const char *s, int c)
{
	const char *occ = NULL;
	while (*(++s - 1)) if (*s == c) occ = s;
	return ((char*)occ);
}