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/****************************************************************************
* include/stdbool.h
*
* Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_STDBOOL_H
#define __INCLUDE_STDBOOL_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
/* If CONFIG_ARCH_STDBOOL_H is set, then the archecture will provide its own
* stdbool.h file. In this case, this header file will simply re-direct to
* the architecture-specfiic stdbool.h header file.
*/
#ifdef CONFIG_ARCH_STDBOOL_H
# include <arch/stdbool.h>
/* NuttX will insist that the sizeof(bool) is 8-bits. The sizeof of _Bool
* used by any specific compiler is implementation specific: It can vary from
* compiler-to-compiler and even vary between different versions of the same
* compiler. Compilers seems to be converging to sizeof(_Bool) == 1. If that
* is true for your compiler, you should define CONFIG_C99_BOOL8 in your NuttX
* configuration for better standards compatibility.
*
* CONFIG_C99_BOOL8 - Means (1) your C++ compiler has sizeof(_Bool) == 8,
* (2) your C compiler supports the C99 _Bool intrinsic type, and (2) that
* the C99 _Bool type also has size 1.
*/
#else
/* nuttx/compiler.h may also define or undefine CONFIG_C99_BOOL8 */
# include <nuttx/compiler.h>
#if !defined(__cplusplus) || !defined(CONFIG_C99_BOOL8)
# include <stdint.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* bool, true, and false must be provided as macros so that they can be
* redefined by the application if necessary.
*
* NOTE: Under C99 'bool' is required to be defined to be the intrinsic type
* _Bool. However, in this NuttX context, we need backward compatibility
* to pre-C99 standards where _Bool is not an intrinsic type. Hence, we
* use _Bool8 as the underlying type (unless CONFIG_C99_BOOL8 is defined)
*/
#ifdef CONFIG_C99_BOOL8
# define bool _Bool
#else
# define bool _Bool8
#endif
#define true (bool)1
#define false (bool)0
#define __bool_true_false_are_defined 1
/****************************************************************************
* Public Types
****************************************************************************/
/* A byte is the smallest address memory element (at least in architectures
* that do not support bit banding). The requirement is only that type _Bool
* be large enough to hold the values 0 and 1. We select uint8_t to minimize
* the RAM footprint of the executable.
*
* NOTE: We can't actually define the type _Bool here. Under C99 _Bool is
* an intrinsic type and cannot be the target of a typedef. However, in this
* NuttX context, we also need backward compatibility to pre-C99 standards
* where _Bool is not an intrinsic type. We work around this by using _Bool8
* as the underlying type.
*/
#ifndef CONFIG_C99_BOOL8
typedef uint8_t _Bool8;
#endif
#endif /* __cplusplus && CONFIG_C99_BOOL8 */
#endif /* CONFIG_ARCH_STDBOOL_H */
#endif /* __INCLUDE_STDBOOL_H */
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