1 /* c-ctype.h: ASCII-safe versions of the <ctype.h> macros.
3 Copyright 1992, 1994, 2008 Karl Berry.
4 Copyright 1998, 2000, 2005 Olaf Weber.
6 This library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 This library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with this library; if not, see <http://www.gnu.org/licenses/>. */
19 #ifndef KPATHSEA_C_CTYPE_H
20 #define KPATHSEA_C_CTYPE_H
24 /* Be sure we have `isascii'. */
33 #define ISALNUM(c) (isascii (c) && isalnum(c))
34 #define ISALPHA(c) (isascii (c) && isalpha(c))
35 #define ISASCII isascii
36 #define ISCNTRL(c) (isascii (c) && iscntrl(c))
37 #define ISDIGIT(c) (isascii (c) && isdigit (c))
38 #define ISGRAPH(c) (isascii (c) && isgraph(c))
39 #define ISLOWER(c) (isascii (c) && islower(c))
40 #define ISPRINT(c) (isascii (c) && isprint(c))
41 #define ISPUNCT(c) (isascii (c) && ispunct(c))
42 #define ISSPACE(c) (isascii (c) && isspace(c))
43 #define ISUPPER(c) (isascii (c) && isupper(c))
44 #define ISXDIGIT(c) (isascii (c) && isxdigit(c))
45 #define TOASCII toascii
46 #define TOLOWER(c) (ISUPPER (c) ? tolower (c) : (c))
47 #define TOUPPER(c) (ISLOWER (c) ? toupper (c) : (c))
49 /* This isn't part of the usual <ctype.h>, but it's useful sometimes. */
51 #define isblank(c) ((c) == ' ' || (c) == '\t')
54 #define ISBLANK(c) (isascii (c) && isblank (c))
57 /* Here's why this mess is necessary:
59 From: meyering@cs.utexas.edu (Jim Meyering)
60 Date: Wed, 25 Nov 1992 09:52:33 -0600
61 Subject: ss-921123: using isascii with <ctype.h> macros
63 Yesterday some cursory regression testing found that GNU od
64 (in an upcoming release of textutils) generated incorrect output
65 when run on an SGI indigo because isprint ('\377') returned true.
66 Of course, '\377' is not a printing character; the problem lay
67 in using isprint without first making sure its integer argument
68 corresponded to an ascii code.
70 MORAL: always guard uses of ctype macros with isascii if it's available.
71 An obvious alternative is to avoid <ctype.h> and define and use your
72 own versions of the ctype macros.
74 A pretty clean approach to using <ctype.h> and isascii was
75 suggested by David MacKenzie:
81 #define ISDIGIT(c) (isascii (c) && isdigit (c))
82 #define ISPRINT(c) (isascii (c) && isprint (c))
85 then, use ISDIGIT, etc. instead of isdigit, etc. */
87 #endif /* not KPATHSEA_C_CTYPE_H */