Merge branch 'mauro' into docs-mw

Another build series from Mauro:

The goal of this series is to drop one of the most ancient and ugliest
hack from the documentation build system. Before migrating to Sphinx,
the media subsystem already had a very comprehensive uAPI book, together
with a build time system to detect and point for any documentation gaps.

When migrating to Sphinx, we ported the logic to a Perl script
(parse-headers.pl) and Markus came up with a Sphinx extension
(kernel_include.py). We also added some files to control how parse-headers
produce results, and a Makefile.

At the initial Sphinx versions (1.4.1 if I recall correctly), when
a new symbol is added to videodev2.h, a new warning were
produced at documentatiion time, it the patchset didn't have
the corresponding documentation path.

While kernel-include is generic, the only user at the moment is the media
subsystem.

This series gets rid of the Python script, replacing it by a command
line script and a class. The parse header class can optionally be used by
kernel-include to produce an enriched code that will contain cross-references.

As the other conversions, it starts with a bug-compatible version of
parse-headers, but the subsequent patches add more functionalities and
fix bugs.

It should be noticed that modern of Sphinx disabled the cross-reference
warnings. So, at the next series, I'll be re-adding it in a controlled way
(e.g. just for the references from kernel-include that has an special
argument).

The script also supports now generating a "toc" output, which will be used
at the next series.

1 files changed, 60 insertions, 0 deletions

diff --git a/tools/docs/parse-headers.py b/tools/docs/parse-headers.py
new file mode 100755
index 000000000000..bfa4e46a53e3
--- /dev/null
+++ b/tools/docs/parse-headers.py
@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2016, 2025 by Mauro Carvalho Chehab <mchehab@kernel.org>.
+# pylint: disable=C0103
+
+"""
+Convert a C header or source file ``FILE_IN``, into a ReStructured Text
+included via ..parsed-literal block with cross-references for the
+documentation files that describe the API. It accepts an optional
+``FILE_RULES`` file to describes what elements will be either ignored or
+be pointed to a non-default reference type/name.
+
+The output is written at ``FILE_OUT``.
+
+It is capable of identifying defines, functions, structs, typedefs,
+enums and enum symbols and create cross-references for all of them.
+It is also capable of distinguish #define used for specifying a Linux
+ioctl.
+
+The optional ``FILE_RULES`` contains a set of rules like:
+
+    ignore ioctl VIDIOC_ENUM_FMT
+    replace ioctl VIDIOC_DQBUF vidioc_qbuf
+    replace define V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ :c:type:`v4l2_event_motion_det`
+"""
+
+import argparse
+
+from lib.parse_data_structs import ParseDataStructs
+from lib.enrich_formatter import EnrichFormatter
+
+def main():
+    """Main function"""
+    parser = argparse.ArgumentParser(description=__doc__,
+                                     formatter_class=EnrichFormatter)
+
+    parser.add_argument("-d", "--debug", action="count", default=0,
+                        help="Increase debug level. Can be used multiple times")
+    parser.add_argument("-t", "--toc", action="store_true",
+                        help="instead of a literal block, outputs a TOC table at the RST file")
+
+    parser.add_argument("file_in", help="Input C file")
+    parser.add_argument("file_out", help="Output RST file")
+    parser.add_argument("file_rules", nargs="?",
+                        help="Exceptions file (optional)")
+
+    args = parser.parse_args()
+
+    parser = ParseDataStructs(debug=args.debug)
+    parser.parse_file(args.file_in)
+
+    if args.file_rules:
+        parser.process_exceptions(args.file_rules)
+
+    parser.debug_print()
+    parser.write_output(args.file_in, args.file_out, args.toc)
+
+
+if __name__ == "__main__":
+    main()