doc: Add a kdoc test for API docs

Even when we're not building docs, it would be handy to have an easy
check that the kernel-doc comments do not produce warnings or errors.

This change adds a test() defintion to docs/, which calls a simple
script, kernel-doc-check. This script invokes kernel-doc, looking for
error and/or warning output.

Signed-off-by: Jeremy Kerr <[email protected]>

Author: jk-ozlabs

doc/kernel-doc-check

@@ -0,0 +1,10 @@
+#!/bin/bash
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+kernel_doc=$(dirname $0)/kernel-doc
+
+"$kernel_doc" -none "$@" 2>&1 |
+  grep '\(warning\|error\)'
+
+# check that kernel-doc succeeded, but the grep failed
+[ ${PIPESTATUS[0]} -eq 0 -a ${PIPESTATUS[1]} -eq 1 ]

doc/meson.build

@@ -46,8 +46,12 @@ subdir('rst')
 
 want_docs = get_option('docs')
 want_docs_build = get_option('docs-build')
+kernel_doc = find_program('kernel-doc')
+kernel_doc_check = find_program('kernel-doc-check')
+
+test('kdoc', kernel_doc_check, args: api_paths)
+
 if want_docs != 'false'
-  kernel_doc = find_program('kernel-doc')
 
   conf = configuration_data()
   conf.set('SYSCONFDIR', sysconfdir)