diff options
Diffstat (limited to 'Documentation/kernel-doc-nano-HOWTO.txt')
| -rw-r--r-- | Documentation/kernel-doc-nano-HOWTO.txt | 97 |
1 files changed, 76 insertions, 21 deletions
diff --git a/Documentation/kernel-doc-nano-HOWTO.txt b/Documentation/kernel-doc-nano-HOWTO.txt index 0bd32748a46..acbc1a3d0d9 100644 --- a/Documentation/kernel-doc-nano-HOWTO.txt +++ b/Documentation/kernel-doc-nano-HOWTO.txt @@ -43,7 +43,8 @@ Only comments so marked will be considered by the kernel-doc scripts, and any comment so marked must be in kernel-doc format. Do not use "/**" to be begin a comment block unless the comment block contains kernel-doc formatted comments. The closing comment marker for -kernel-doc comments can be either "*/" or "**/". +kernel-doc comments can be either "*/" or "**/", but "*/" is +preferred in the Linux kernel tree. Kernel-doc comments should be placed just before the function or data structure being described. @@ -63,14 +64,25 @@ Example kernel-doc function comment: * comment lines. * * The longer description can have multiple paragraphs. - **/ + * + * Return: Describe the return value of foobar. + */ -The first line, with the short description, must be on a single line. +The short description following the subject can span multiple lines +and ends with an @argument description, an empty line or the end of +the comment block. The @argument descriptions must begin on the very next line following this opening short function description line, with no intervening empty comment lines. +If a function parameter is "..." (varargs), it should be listed in +kernel-doc notation as: + * @...: description + +The return value, if any, should be described in a dedicated section +named "Return". + Example kernel-doc data structure comment. /** @@ -80,7 +92,7 @@ Example kernel-doc data structure comment. * perhaps with more lines and words. * * Longer description of this structure. - **/ + */ The kernel-doc function comments describe each parameter to the function, in order, with the @name lines. @@ -130,9 +142,10 @@ are: - Makefile - The targets 'sgmldocs', 'psdocs', 'pdfdocs', and 'htmldocs' are used - to build DocBook files, PostScript files, PDF files, and html files - in Documentation/DocBook. + The targets 'xmldocs', 'psdocs', 'pdfdocs', and 'htmldocs' are used + to build XML DocBook files, PostScript files, PDF files, and html files + in Documentation/DocBook. The older target 'sgmldocs' is equivalent + to 'xmldocs'. - Documentation/DocBook/Makefile @@ -146,8 +159,8 @@ If you just want to read the ready-made books on the various subsystems (see Documentation/DocBook/*.tmpl), just type 'make psdocs', or 'make pdfdocs', or 'make htmldocs', depending on your preference. If you would rather read a different format, you can type -'make sgmldocs' and then use DocBook tools to convert -Documentation/DocBook/*.sgml to a format of your choice (for example, +'make xmldocs' and then use DocBook tools to convert +Documentation/DocBook/*.xml to a format of your choice (for example, 'db2html ...' if 'make htmldocs' was not defined). If you want to see man pages instead, you can do this: @@ -168,10 +181,10 @@ if ($#ARGV < 0) { mkdir $ARGV[0],0777; $state = 0; while (<STDIN>) { - if (/^\.TH \"[^\"]*\" 4 \"([^\"]*)\"/) { + if (/^\.TH \"[^\"]*\" 9 \"([^\"]*)\"/) { if ($state == 1) { close OUT } $state = 1; - $fn = "$ARGV[0]/$1.4"; + $fn = "$ARGV[0]/$1.9"; print STDERR "Creating $fn\n"; open OUT, ">$fn" or die "can't open $fn: $!\n"; print OUT $_; @@ -206,11 +219,16 @@ The format of the block comment is like this: * (section header: (section description)? )* (*)?*/ -The short function description ***cannot be multiline***, but the other -descriptions can be (and they can contain blank lines). If you continue -that initial short description onto a second line, that second line will -appear further down at the beginning of the description section, which is -almost certainly not what you had in mind. +All "description" text can span multiple lines, although the +function_name & its short description are traditionally on a single line. +Description text may also contain blank lines (i.e., lines that contain +only a "*"). + +"section header:" names must be unique per function (or struct, +union, typedef, enum). + +Use the section header "Return" for sections describing the return value +of a function. Avoid putting a spurious blank line after the function name, or else the description will be repeated! @@ -227,21 +245,21 @@ patterns, which are highlighted appropriately. NOTE 1: The multi-line descriptive text you provide does *not* recognize line breaks, so if you try to format some text nicely, as in: - Return codes + Return: 0 - cool 1 - invalid arg 2 - out of memory this will all run together and produce: - Return codes 0 - cool 1 - invalid arg 2 - out of memory + Return: 0 - cool 1 - invalid arg 2 - out of memory NOTE 2: If the descriptive text you provide has lines that begin with some phrase followed by a colon, each of those phrases will be taken as a new section heading, which means you should similarly try to avoid text like: - Return codes: + Return: 0: cool 1: invalid arg 2: out of memory @@ -263,7 +281,10 @@ Use the argument mechanism to document members or constants. Inside a struct description, you can use the "private:" and "public:" comment tags. Structure fields that are inside a "private:" area -are not listed in the generated output documentation. +are not listed in the generated output documentation. The "private:" +and "public:" tags must begin immediately following a "/*" comment +marker. They may optionally include comments between the ":" and the +ending "*/" marker. Example: @@ -277,11 +298,37 @@ Example: struct my_struct { int a; int b; -/* private: */ +/* private: internal use only */ int c; }; +Including documentation blocks in source files +---------------------------------------------- + +To facilitate having source code and comments close together, you can +include kernel-doc documentation blocks that are free-form comments +instead of being kernel-doc for functions, structures, unions, +enums, or typedefs. This could be used for something like a +theory of operation for a driver or library code, for example. + +This is done by using a DOC: section keyword with a section title. E.g.: + +/** + * DOC: Theory of Operation + * + * The whizbang foobar is a dilly of a gizmo. It can do whatever you + * want it to do, at any time. It reads your mind. Here's how it works. + * + * foo bar splat + * + * The only drawback to this gizmo is that is can sometimes damage + * hardware, software, or its subject(s). + */ + +DOC: sections are used in SGML templates files as indicated below. + + How to make new SGML template files ----------------------------------- @@ -302,6 +349,14 @@ exported using EXPORT_SYMBOL. !F<filename> <function [functions...]> is replaced by the documentation, in <filename>, for the functions listed. +!P<filename> <section title> is replaced by the contents of the DOC: +section titled <section title> from <filename>. +Spaces are allowed in <section title>; do not quote the <section title>. + +!C<filename> is replaced by nothing, but makes the tools check that +all DOC: sections and documented functions, symbols, etc. are used. +This makes sense to use when you use !F/!P only and want to verify +that all documentation is included. Tim. */ <twaugh@redhat.com> |