1 /*
2 Copyright (c) 1989 The Regents of the University of California.
3 All rights reserved.
4
5 Redistribution and use in source and binary forms, with or without
6 modification, are permitted provided that the following conditions
7 are met:
8 1. Redistributions of source code must retain the above copyright
9 notice, this list of conditions and the following disclaimer.
10 2. Redistributions in binary form must reproduce the above copyright
11 notice, this list of conditions and the following disclaimer in the
12 documentation and/or other materials provided with the distribution.
13 3. Neither the name of the University nor the names of its contributors
14 may be used to endorse or promote products derived from this software
15 without specific prior written permission.
16
17 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 SUCH DAMAGE.
28 */
29 /*
30 FUNCTION
31 <<isalnum>>, <<isalnum_l>>---alphanumeric character predicate
32
33 INDEX
34 isalnum
35 INDEX
36 isalnum_l
37
38 SYNOPSIS
39 #include <ctype.h>
40 int isalnum(int <[c]>);
41
42 #include <ctype.h>
43 int isalnum_l(int <[c]>, locale_t <[locale]>);
44
45
46 DESCRIPTION
47 <<isalnum>> is a macro which classifies singlebyte charset values by table
48 lookup. It is a predicate returning non-zero for alphabetic or
49 numeric ASCII characters, and <<0>> for other arguments. It is defined
50 only if <[c]> is representable as an unsigned char or if <[c]> is EOF.
51
52 <<isalnum_l>> is like <<isalnum>> but performs the check based on the
53 locale specified by the locale object locale. If <[locale]> is
54 LC_GLOBAL_LOCALE or not a valid locale object, the behaviour is undefined.
55
56 You can use a compiled subroutine instead of the macro definition by
57 undefining the macro using `<<#undef isalnum>>' or `<<#undef isalnum_l>>'.
58
59 RETURNS
60 <<isalnum>>,<<isalnum_l>> return non-zero if <[c]> is a letter or a digit.
61
62 PORTABILITY
63 <<isalnum>> is ANSI C.
64 <<isalnum_l>> is POSIX-1.2008.
65
66 No OS subroutines are required.
67 */
68
69 #include <ctype.h>
70
71 #undef isalnum
72 int
isalnum(int c)73 isalnum (int c)
74 {
75 #if _PICOLIBC_CTYPE_SMALL
76 return isalpha(c) || isdigit(c);
77 #else
78 return __CTYPE_PTR[c+1] & (_U|_L|_N);
79 #endif
80 }
81
