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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _TOOLS_LINUX_KCONFIG_H3#define _TOOLS_LINUX_KCONFIG_H4 5/* CONFIG_CC_VERSION_TEXT (Do not delete this comment. See help in Kconfig) */6 7#define __ARG_PLACEHOLDER_1 0,8#define __take_second_arg(__ignored, val, ...) val9 10/*11 * The use of "&&" / "||" is limited in certain expressions.12 * The following enable to calculate "and" / "or" with macro expansion only.13 */14#define __and(x, y) ___and(x, y)15#define ___and(x, y) ____and(__ARG_PLACEHOLDER_##x, y)16#define ____and(arg1_or_junk, y) __take_second_arg(arg1_or_junk y, 0)17 18#define __or(x, y) ___or(x, y)19#define ___or(x, y) ____or(__ARG_PLACEHOLDER_##x, y)20#define ____or(arg1_or_junk, y) __take_second_arg(arg1_or_junk 1, y)21 22/*23 * Helper macros to use CONFIG_ options in C/CPP expressions. Note that24 * these only work with boolean and tristate options.25 */26 27/*28 * Getting something that works in C and CPP for an arg that may or may29 * not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"30 * we match on the placeholder define, insert the "0," for arg1 and generate31 * the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).32 * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when33 * the last step cherry picks the 2nd arg, we get a zero.34 */35#define __is_defined(x) ___is_defined(x)36#define ___is_defined(val) ____is_defined(__ARG_PLACEHOLDER_##val)37#define ____is_defined(arg1_or_junk) __take_second_arg(arg1_or_junk 1, 0)38 39/*40 * IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 041 * otherwise. For boolean options, this is equivalent to42 * IS_ENABLED(CONFIG_FOO).43 */44#define IS_BUILTIN(option) __is_defined(option)45 46/*47 * IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 048 * otherwise.49 */50#define IS_MODULE(option) __is_defined(option##_MODULE)51 52/*53 * IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled54 * code can call a function defined in code compiled based on CONFIG_FOO.55 * This is similar to IS_ENABLED(), but returns false when invoked from56 * built-in code when CONFIG_FOO is set to 'm'.57 */58#define IS_REACHABLE(option) __or(IS_BUILTIN(option), \59 __and(IS_MODULE(option), __is_defined(MODULE)))60 61/*62 * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',63 * 0 otherwise.64 */65#define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))66 67#endif /* _TOOLS_LINUX_KCONFIG_H */68