scripts/kernel-doc: Add support for named variable macro arguments
Currently, when kernel-doc encounters a macro with a named variable
argument[1], such as this:
#define hlist_for_each_entry_rcu(pos, head, member, cond...)
... it expects the variable argument to be documented as `cond...`,
rather than `cond`. This is semantically wrong, because the name (as
used in the macro body) is actually `cond`.
With this patch, kernel-doc will accept the name without dots (`cond`
in the example above) in doc comments, and warn if the name with dots
(`cond...`) is used and verbose mode[2] is enabled.
The support for the `cond...` syntax can be removed later, when the
documentation of all such macros has been switched to the new syntax.
Testing this patch on top of v5.4-rc6, `make htmldocs` shows a few
changes in log output and HTML output:
1) The following warnings[3] are eliminated:
./include/linux/rculist.h:374: warning:
Excess function parameter 'cond' description in 'list_for_each_entry_rcu'
./include/linux/rculist.h:651: warning:
Excess function parameter 'cond' description in 'hlist_for_each_entry_rcu'
2) For list_for_each_entry_rcu and hlist_for_each_entry_rcu, the
correct description is shown
3) Named variable arguments are shown without dots
[1]: https://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html
[2]: scripts/kernel-doc -v
[3]: See also https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?h=dev&id=5bc4bc0d6153617eabde275285b7b5a8137fdf3c
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index a529375..f2d73f0 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -1450,6 +1450,10 @@
# handles unnamed variable parameters
$param = "...";
}
+ elsif ($param =~ /\w\.\.\.$/) {
+ # for named variable parameters of the form `x...`, remove the dots
+ $param =~ s/\.\.\.$//;
+ }
if (!defined $parameterdescs{$param} || $parameterdescs{$param} eq "") {
$parameterdescs{$param} = "variable arguments";
}
@@ -1937,6 +1941,18 @@
sub process_body($$) {
my $file = shift;
+ # Until all named variable macro parameters are
+ # documented using the bare name (`x`) rather than with
+ # dots (`x...`), strip the dots:
+ if ($section =~ /\w\.\.\.$/) {
+ $section =~ s/\.\.\.$//;
+
+ if ($verbose) {
+ print STDERR "${file}:$.: warning: Variable macro arguments should be documented without dots\n";
+ ++$warnings;
+ }
+ }
+
if (/$doc_sect/i) { # case insensitive for supported section names
$newsection = $1;
$newcontents = $2;