Merge commit 'b572c3a256e7bf1e4eecc8c36448c08093240a6a' into stable

[gnulib.git] / lib / c-ctype.h

diff --git a/lib/c-ctype.h b/lib/c-ctype.h
index 395c7a1..078bd9a 100644 (file)
--- a/lib/c-ctype.h
+++ b/lib/c-ctype.h
@@ -5,7 +5,7 @@
    <ctype.h> functions' behaviour depends on the current locale set via
    setlocale.
 
-   Copyright (C) 2000-2003, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2000-2003, 2006, 2008-2011 Free Software Foundation, Inc.
 
 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
@@ -27,6 +27,11 @@ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 #include <stdbool.h>
 
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
 /* The functions defined in this file assume the "C" locale and a character
    set without diacritics (ASCII-US or EBCDIC-US or something like that).
    Even if the "C" locale on a particular system is an extension of the ASCII
@@ -98,23 +103,38 @@ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 
 /* Function declarations. */
 
-extern bool c_isascii (int c); /* not locale dependent */
+/* Unlike the functions in <ctype.h>, which require an argument in the range
+   of the 'unsigned char' type, the functions here operate on values that are
+   in the 'unsigned char' range or in the 'char' range.  In other words,
+   when you have a 'char' value, you need to cast it before using it as
+   argument to a <ctype.h> function:
+
+         const char *s = ...;
+         if (isalpha ((unsigned char) *s)) ...
+
+   but you don't need to cast it for the functions defined in this file:
 
-extern bool c_isalnum (int c);
-extern bool c_isalpha (int c);
-extern bool c_isblank (int c);
-extern bool c_iscntrl (int c);
-extern bool c_isdigit (int c);
-extern bool c_islower (int c);
-extern bool c_isgraph (int c);
-extern bool c_isprint (int c);
-extern bool c_ispunct (int c);
-extern bool c_isspace (int c);
-extern bool c_isupper (int c);
-extern bool c_isxdigit (int c);
+         const char *s = ...;
+         if (c_isalpha (*s)) ...
+ */
 
-extern int c_tolower (int c);
-extern int c_toupper (int c);
+extern bool c_isascii (int c) _GL_ATTRIBUTE_CONST; /* not locale dependent */
+
+extern bool c_isalnum (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isalpha (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isblank (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_iscntrl (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isdigit (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_islower (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isgraph (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isprint (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_ispunct (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isspace (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isupper (int c) _GL_ATTRIBUTE_CONST;
+extern bool c_isxdigit (int c) _GL_ATTRIBUTE_CONST;
+
+extern int c_tolower (int c) _GL_ATTRIBUTE_CONST;
+extern int c_toupper (int c) _GL_ATTRIBUTE_CONST;
 
 
 #if defined __GNUC__ && defined __OPTIMIZE__ && !defined __OPTIMIZE_SIZE__ && !defined NO_C_CTYPE_MACROS
@@ -267,4 +287,9 @@ extern int c_toupper (int c);
 
 #endif /* optimizing for speed */
 
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* C_CTYPE_H */