Commit | Line | Data |
---|---|---|
93281c4a BP |
1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _TOOLS_LINUX_KCONFIG_H | |
3 | #define _TOOLS_LINUX_KCONFIG_H | |
4 | ||
5 | /* CONFIG_CC_VERSION_TEXT (Do not delete this comment. See help in Kconfig) */ | |
6 | ||
93281c4a BP |
7 | #define __ARG_PLACEHOLDER_1 0, |
8 | #define __take_second_arg(__ignored, val, ...) val | |
9 | ||
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 that | |
24 | * 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 may | |
29 | * 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 generate | |
31 | * 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 when | |
33 | * 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', 0 | |
41 | * otherwise. For boolean options, this is equivalent to | |
42 | * 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', 0 | |
48 | * otherwise. | |
49 | */ | |
50 | #define IS_MODULE(option) __is_defined(option##_MODULE) | |
51 | ||
52 | /* | |
53 | * IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled | |
54 | * 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 from | |
56 | * 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 */ |