diff options
| author | Robert P. J. Day | 2006-12-22 01:09:11 -0800 |
|---|---|---|
| committer | Linus Torvalds | 2006-12-22 08:55:49 -0800 |
| commit | 58637ec90b7ceed5909e726ac90118852f79d2b1 (patch) | |
| tree | f5478b2f088d31b609ed07bb10fb641bad7cd10e /Documentation/CodingStyle | |
| parent | 163ca88b9c5858909ee3f8801ae0096b5f94e835 (diff) | |
[PATCH] Add a new section to CodingStyle, promoting include/linux/kernel.h
Add a new section to the CodingStyle file, encouraging people not to
re-invent available kernel macros such as ARRAY_SIZE(), FIELD_SIZEOF(),
min() and max(), among others.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'Documentation/CodingStyle')
| -rw-r--r-- | Documentation/CodingStyle | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index 0ad6dcb5d45f..9069189e78ef 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -682,6 +682,24 @@ result. Typical examples would be functions that return pointers; they use NULL or the ERR_PTR mechanism to report failure. + Chapter 17: Don't re-invent the kernel macros + +The header file include/linux/kernel.h contains a number of macros that +you should use, rather than explicitly coding some variant of them yourself. +For example, if you need to calculate the length of an array, take advantage +of the macro + + #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +Similarly, if you need to calculate the size of some structure member, use + + #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) + +There are also min() and max() macros that do strict type checking if you +need them. Feel free to peruse that header file to see what else is already +defined that you shouldn't reproduce in your code. + + Appendix I: References |