kconfig.h 2.4 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef _TOOLS_LINUX_KCONFIG_H
  3. #define _TOOLS_LINUX_KCONFIG_H
  4. /* CONFIG_CC_VERSION_TEXT (Do not delete this comment. See help in Kconfig) */
  5. #define __ARG_PLACEHOLDER_1 0,
  6. #define __take_second_arg(__ignored, val, ...) val
  7. /*
  8. * The use of "&&" / "||" is limited in certain expressions.
  9. * The following enable to calculate "and" / "or" with macro expansion only.
  10. */
  11. #define __and(x, y) ___and(x, y)
  12. #define ___and(x, y) ____and(__ARG_PLACEHOLDER_##x, y)
  13. #define ____and(arg1_or_junk, y) __take_second_arg(arg1_or_junk y, 0)
  14. #define __or(x, y) ___or(x, y)
  15. #define ___or(x, y) ____or(__ARG_PLACEHOLDER_##x, y)
  16. #define ____or(arg1_or_junk, y) __take_second_arg(arg1_or_junk 1, y)
  17. /*
  18. * Helper macros to use CONFIG_ options in C/CPP expressions. Note that
  19. * these only work with boolean and tristate options.
  20. */
  21. /*
  22. * Getting something that works in C and CPP for an arg that may or may
  23. * not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"
  24. * we match on the placeholder define, insert the "0," for arg1 and generate
  25. * the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).
  26. * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
  27. * the last step cherry picks the 2nd arg, we get a zero.
  28. */
  29. #define __is_defined(x) ___is_defined(x)
  30. #define ___is_defined(val) ____is_defined(__ARG_PLACEHOLDER_##val)
  31. #define ____is_defined(arg1_or_junk) __take_second_arg(arg1_or_junk 1, 0)
  32. /*
  33. * IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
  34. * otherwise. For boolean options, this is equivalent to
  35. * IS_ENABLED(CONFIG_FOO).
  36. */
  37. #define IS_BUILTIN(option) __is_defined(option)
  38. /*
  39. * IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
  40. * otherwise.
  41. */
  42. #define IS_MODULE(option) __is_defined(option##_MODULE)
  43. /*
  44. * IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled
  45. * code can call a function defined in code compiled based on CONFIG_FOO.
  46. * This is similar to IS_ENABLED(), but returns false when invoked from
  47. * built-in code when CONFIG_FOO is set to 'm'.
  48. */
  49. #define IS_REACHABLE(option) __or(IS_BUILTIN(option), \
  50. __and(IS_MODULE(option), __is_defined(MODULE)))
  51. /*
  52. * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
  53. * 0 otherwise.
  54. */
  55. #define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
  56. #endif /* _TOOLS_LINUX_KCONFIG_H */