mirror of
https://git.proxmox.com/git/grub2
synced 2025-11-04 14:51:07 +00:00
133 lines
5.0 KiB
C
133 lines
5.0 KiB
C
/* Copyright (C) 2001-2003, 2006-2013 Free Software Foundation, Inc.
|
|
Written by Bruno Haible <haible@clisp.cons.org>, 2001.
|
|
|
|
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, 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/>. */
|
|
|
|
#ifndef _GL_STDBOOL_H
|
|
#define _GL_STDBOOL_H
|
|
|
|
/* ISO C 99 <stdbool.h> for platforms that lack it. */
|
|
|
|
/* Usage suggestions:
|
|
|
|
Programs that use <stdbool.h> should be aware of some limitations
|
|
and standards compliance issues.
|
|
|
|
Standards compliance:
|
|
|
|
- <stdbool.h> must be #included before 'bool', 'false', 'true'
|
|
can be used.
|
|
|
|
- You cannot assume that sizeof (bool) == 1.
|
|
|
|
- Programs should not undefine the macros bool, true, and false,
|
|
as C99 lists that as an "obsolescent feature".
|
|
|
|
Limitations of this substitute, when used in a C89 environment:
|
|
|
|
- <stdbool.h> must be #included before the '_Bool' type can be used.
|
|
|
|
- You cannot assume that _Bool is a typedef; it might be a macro.
|
|
|
|
- Bit-fields of type 'bool' are not supported. Portable code
|
|
should use 'unsigned int foo : 1;' rather than 'bool foo : 1;'.
|
|
|
|
- In C99, casts and automatic conversions to '_Bool' or 'bool' are
|
|
performed in such a way that every nonzero value gets converted
|
|
to 'true', and zero gets converted to 'false'. This doesn't work
|
|
with this substitute. With this substitute, only the values 0 and 1
|
|
give the expected result when converted to _Bool' or 'bool'.
|
|
|
|
- C99 allows the use of (_Bool)0.0 in constant expressions, but
|
|
this substitute cannot always provide this property.
|
|
|
|
Also, it is suggested that programs use 'bool' rather than '_Bool';
|
|
this isn't required, but 'bool' is more common. */
|
|
|
|
|
|
/* 7.16. Boolean type and values */
|
|
|
|
/* BeOS <sys/socket.h> already #defines false 0, true 1. We use the same
|
|
definitions below, but temporarily we have to #undef them. */
|
|
#if defined __BEOS__ && !defined __HAIKU__
|
|
# include <OS.h> /* defines bool but not _Bool */
|
|
# undef false
|
|
# undef true
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
# define _Bool bool
|
|
# define bool bool
|
|
#else
|
|
# if defined __BEOS__ && !defined __HAIKU__
|
|
/* A compiler known to have 'bool'. */
|
|
/* If the compiler already has both 'bool' and '_Bool', we can assume they
|
|
are the same types. */
|
|
# if !@HAVE__BOOL@
|
|
typedef bool _Bool;
|
|
# endif
|
|
# else
|
|
# if !defined __GNUC__
|
|
/* If @HAVE__BOOL@:
|
|
Some HP-UX cc and AIX IBM C compiler versions have compiler bugs when
|
|
the built-in _Bool type is used. See
|
|
http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html
|
|
http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html
|
|
http://lists.gnu.org/archive/html/bug-coreutils/2005-10/msg00086.html
|
|
Similar bugs are likely with other compilers as well; this file
|
|
wouldn't be used if <stdbool.h> was working.
|
|
So we override the _Bool type.
|
|
If !@HAVE__BOOL@:
|
|
Need to define _Bool ourselves. As 'signed char' or as an enum type?
|
|
Use of a typedef, with SunPRO C, leads to a stupid
|
|
"warning: _Bool is a keyword in ISO C99".
|
|
Use of an enum type, with IRIX cc, leads to a stupid
|
|
"warning(1185): enumerated type mixed with another type".
|
|
Even the existence of an enum type, without a typedef,
|
|
"Invalid enumerator. (badenum)" with HP-UX cc on Tru64.
|
|
The only benefit of the enum, debuggability, is not important
|
|
with these compilers. So use 'signed char' and no enum. */
|
|
# define _Bool signed char
|
|
# else
|
|
/* With this compiler, trust the _Bool type if the compiler has it. */
|
|
# if !@HAVE__BOOL@
|
|
/* For the sake of symbolic names in gdb, define true and false as
|
|
enum constants, not only as macros.
|
|
It is tempting to write
|
|
typedef enum { false = 0, true = 1 } _Bool;
|
|
so that gdb prints values of type 'bool' symbolically. But then
|
|
values of type '_Bool' might promote to 'int' or 'unsigned int'
|
|
(see ISO C 99 6.7.2.2.(4)); however, '_Bool' must promote to 'int'
|
|
(see ISO C 99 6.3.1.1.(2)). So add a negative value to the
|
|
enum; this ensures that '_Bool' promotes to 'int'. */
|
|
typedef enum { _Bool_must_promote_to_int = -1, false = 0, true = 1 } _Bool;
|
|
# endif
|
|
# endif
|
|
# endif
|
|
# define bool _Bool
|
|
#endif
|
|
|
|
/* The other macros must be usable in preprocessor directives. */
|
|
#ifdef __cplusplus
|
|
# define false false
|
|
# define true true
|
|
#else
|
|
# define false 0
|
|
# define true 1
|
|
#endif
|
|
|
|
#define __bool_true_false_are_defined 1
|
|
|
|
#endif /* _GL_STDBOOL_H */
|