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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_KCONFIG_H
#define __LINUX_KCONFIG_H
#include <generated/autoconf.h>
#ifdef CONFIG_CPU_BIG_ENDIAN
#define __BIG_ENDIAN 4321
#else
#define __LITTLE_ENDIAN 1234
#endif
#define __ARG_PLACEHOLDER_1 0,
#define __take_second_arg(__ignored, val, ...) val
/*
* The use of "&&" / "||" is limited in certain expressions.
* The following enable to calculate "and" / "or" with macro expansion only.
*/
#define __and(x, y) ___and(x, y)
#define ___and(x, y) ____and(__ARG_PLACEHOLDER_##x, y)
#define ____and(arg1_or_junk, y) __take_second_arg(arg1_or_junk y, 0)
#define __or(x, y) ___or(x, y)
#define ___or(x, y) ____or(__ARG_PLACEHOLDER_##x, y)
#define ____or(arg1_or_junk, y) __take_second_arg(arg1_or_junk 1, y)
/*
* Helper macros to use CONFIG_ options in C/CPP expressions. Note that
* these only work with boolean and tristate options.
*/
/*
* Getting something that works in C and CPP for an arg that may or may
* not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"
* we match on the placeholder define, insert the "0," for arg1 and generate
* the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).
* When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
* the last step cherry picks the 2nd arg, we get a zero.
*/
#define __is_defined(x) ___is_defined(x)
#define ___is_defined(val) ____is_defined(__ARG_PLACEHOLDER_##val)
#define ____is_defined(arg1_or_junk) __take_second_arg(arg1_or_junk 1, 0)
/*
* IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
* otherwise. For boolean options, this is equivalent to
* IS_ENABLED(CONFIG_FOO).
*/
#define IS_BUILTIN(option) __is_defined(option)
/*
* IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
* otherwise. CONFIG_FOO=m results in "#define CONFIG_FOO_MODULE 1" in
* autoconf.h.
*/
#define IS_MODULE(option) __is_defined(option##_MODULE)
/*
* IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled
* code can call a function defined in code compiled based on CONFIG_FOO.
* This is similar to IS_ENABLED(), but returns false when invoked from
* built-in code when CONFIG_FOO is set to 'm'.
*/
#define IS_REACHABLE(option) __or(IS_BUILTIN(option), \
__and(IS_MODULE(option), __is_defined(MODULE)))
/*
* IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
* 0 otherwise. Note that CONFIG_FOO=y results in "#define CONFIG_FOO 1" in
* autoconf.h, while CONFIG_FOO=m results in "#define CONFIG_FOO_MODULE 1".
*/
#define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
#endif /* __LINUX_KCONFIG_H */
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