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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_IS_DEFINED_H_
#define __LINUX_IS_DEFINED_H_
#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)
#define __if_defined(x, a, b) ___if_defined(__is_defined(x), a, b)
#define ___if_defined(val, a, b) ____if_defined(val, a, b)
#define ____if_defined(val, a, b) ____if_defined_##val(a, b)
#define ____if_defined_1(a, b) a
#define ____if_defined_0(a, b) b
#endif
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