| /* Copyright (C) 2001-2003, 2006-2017, 2019 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 Lesser General Public License as published by |
| the Free Software Foundation; either version 2, 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 Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with this program; if not, see <https://www.gnu.org/licenses/>. */ |
| |
| #ifndef _TEXTSTYLE_STDBOOL_H |
| #define _TEXTSTYLE_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 */ |
| |
| #ifdef __cplusplus |
| /* Assume the compiler has 'bool' and '_Bool'. */ |
| #else |
| /* <stdbool.h> is known to exist and work with the following compilers: |
| - GNU C 3.0 or newer, on any platform, |
| - Intel C, |
| - MSVC 12 (Visual Studio 2013) or newer, |
| - Sun C, on Solaris, if _STDC_C99 is defined, |
| - AIX xlc, if _ANSI_C_SOURCE is defined, |
| - HP C, on HP-UX 11.31 or newer. |
| It is know not to work with: |
| - Sun C, on Solaris, if __C99FEATURES__ is defined but _STDC_C99 is not, |
| - MIPSpro C 7.30, on IRIX. */ |
| # if (__GNUC__ >= 3) \ |
| || defined __INTEL_COMPILER \ |
| || (_MSC_VER >= 1800) \ |
| || (defined __SUNPRO_C && defined _STDC_C99) \ |
| || (defined _AIX && !defined __GNUC__ && defined _ANSI_C_SOURCE) \ |
| || defined __HP_cc |
| /* Assume the compiler has <stdbool.h>. */ |
| # include <stdbool.h> |
| # else |
| /* 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 |
| # define bool _Bool |
| # endif |
| #endif |
| |
| /* The other macros must be usable in preprocessor directives. */ |
| #ifdef __cplusplus |
| # define false false |
| # define true true |
| #else |
| # undef false |
| # define false 0 |
| # undef true |
| # define true 1 |
| #endif |
| |
| #define __bool_true_false_are_defined 1 |
| |
| #endif /* _TEXTSTYLE_STDBOOL_H */ |