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Diffstat (limited to 'Documentation/CodingStyle')
| -rw-r--r-- | Documentation/CodingStyle | 66 |
1 files changed, 46 insertions, 20 deletions
diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index 9069189e78ef..b49b92edb396 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -160,6 +160,21 @@ supply of new-lines on your screen is not a renewable resource (think 25-line terminal screens here), you have more empty lines to put comments on. +Do not unnecessarily use braces where a single statement will do. + +if (condition) + action(); + +This does not apply if one branch of a conditional statement is a single +statement. Use braces in both branches. + +if (condition) { + do_this(); + do_that(); +} else { + otherwise(); +} + 3.1: Spaces Linux kernel style for use of spaces depends (mostly) on @@ -480,29 +495,40 @@ re-formatting you may want to take a look at the man page. But remember: "indent" is not a fix for bad programming. - Chapter 10: Configuration-files - -For configuration options (arch/xxx/Kconfig, and all the Kconfig files), -somewhat different indentation is used. + Chapter 10: Kconfig configuration files -Help text is indented with 2 spaces. +For all of the Kconfig* configuration files throughout the source tree, +the indentation is somewhat different. Lines under a "config" definition +are indented with one tab, while help text is indented an additional two +spaces. Example: -if CONFIG_EXPERIMENTAL - tristate CONFIG_BOOM - default n - help - Apply nitroglycerine inside the keyboard (DANGEROUS) - bool CONFIG_CHEER - depends on CONFIG_BOOM - default y +config AUDIT + bool "Auditing support" + depends on NET help - Output nice messages when you explode -endif + Enable auditing infrastructure that can be used with another + kernel subsystem, such as SELinux (which requires this for + logging of avc messages output). Does not do system-call + auditing without CONFIG_AUDITSYSCALL. + +Features that might still be considered unstable should be defined as +dependent on "EXPERIMENTAL": + +config SLUB + depends on EXPERIMENTAL && !ARCH_USES_SLAB_PAGE_STRUCT + bool "SLUB (Unqueued Allocator)" + ... + +while seriously dangerous features (such as write support for certain +filesystems) should advertise this prominently in their prompt string: + +config ADFS_FS_RW + bool "ADFS write support (DANGEROUS)" + depends on ADFS_FS + ... -Generally, CONFIG_EXPERIMENTAL should surround all options not considered -stable. All options that are known to trash data (experimental write- -support for file-systems, for instance) should be denoted (DANGEROUS), other -experimental options should be denoted (EXPERIMENTAL). +For full documentation on the configuration files, see the file +Documentation/kbuild/kconfig-language.txt. Chapter 11: Data structures @@ -625,7 +651,7 @@ language. There appears to be a common misperception that gcc has a magic "make me faster" speedup option called "inline". While the use of inlines can be -appropriate (for example as a means of replacing macros, see Chapter 11), it +appropriate (for example as a means of replacing macros, see Chapter 12), it very often is not. Abundant use of the inline keyword leads to a much bigger kernel, which in turn slows the system as a whole down, due to a bigger icache footprint for the CPU and simply because there is less memory |