[libcamera-devel] [PATCH] libcamera: Auto-generate libcamera.h

[Laurent Pinchart]

Hi Kieran,

On Wed, May 22, 2019 at 02:25:59PM +0100, Kieran Bingham wrote:
> On 21/05/2019 17:45, Laurent Pinchart wrote:
> > As shown by two missing includes, keeping the libcamera.h file in sync
> > when adding or removing headers is an error-prone manual process.
> > Automate it by generating the header automatically.
> > 
> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> >  include/libcamera/gen-header.sh | 26 ++++++++++++++++++++++++++
> >  include/libcamera/libcamera.h   | 20 --------------------
> >  include/libcamera/meson.build   | 10 +++++++++-
> >  3 files changed, 35 insertions(+), 21 deletions(-)
> >  create mode 100755 include/libcamera/gen-header.sh
> >  delete mode 100644 include/libcamera/libcamera.h
> > 
> > diff --git a/include/libcamera/gen-header.sh b/include/libcamera/gen-header.sh
> > new file mode 100755
> > index 000000000000..ea5b79a62520
> > --- /dev/null
> > +++ b/include/libcamera/gen-header.sh
> > @@ -0,0 +1,26 @@
> > +#!/bin/sh
> > +
> > +src_dir=$1
> > +dst_file=$2
> > +
> > +cat <<EOF > $dst_file
> > +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> > +/* This file is auto-generated, do not edit! */
> > +/*
> > + * Copyright (C) 2018, Google Inc.
> > + *
> > + * libcamera.h - libcamera public API
> > + */
> > +#ifndef __LIBCAMERA_LIBCAMERA_H__
> > +#define __LIBCAMERA_LIBCAMERA_H__
> > +
> > +EOF
> > +
> > +for header in $src_dir/*.h ; do
> > +	echo "#include <libcamera/$(basename $header)>" >> $dst_file
> > +done
> > +
> > +cat <<EOF >> $dst_file
> > +
> > +#endif /* __LIBCAMERA_LIBCAMERA_H__ */
> > +EOF
> > diff --git a/include/libcamera/libcamera.h b/include/libcamera/libcamera.h
> > deleted file mode 100644
> > index dda576e906fb..000000000000
> > --- a/include/libcamera/libcamera.h
> > +++ /dev/null
> > @@ -1,20 +0,0 @@
> > -/* SPDX-License-Identifier: LGPL-2.1-or-later */
> > -/*
> > - * Copyright (C) 2018, Google Inc.
> > - *
> > - * libcamera.h - libcamera public API
> > - */
> > -#ifndef __LIBCAMERA_LIBCAMERA_H__
> > -#define __LIBCAMERA_LIBCAMERA_H__
> > -
> > -#include <libcamera/buffer.h>
> > -#include <libcamera/camera.h>
> > -#include <libcamera/camera_manager.h>
> > -#include <libcamera/event_dispatcher.h>
> > -#include <libcamera/event_notifier.h>
> > -#include <libcamera/request.h>
> > -#include <libcamera/signal.h>
> > -#include <libcamera/stream.h>
> > -#include <libcamera/timer.h>
> > -
> > -#endif /* __LIBCAMERA_LIBCAMERA_H__ */
> > diff --git a/include/libcamera/meson.build b/include/libcamera/meson.build
> > index 83d226ac5078..46aff0b6bc2f 100644
> > --- a/include/libcamera/meson.build
> > +++ b/include/libcamera/meson.build
> > @@ -5,7 +5,6 @@ libcamera_api = files([
> >      'event_dispatcher.h',
> >      'event_notifier.h',
> >      'geometry.h',
> > -    'libcamera.h',
> >      'object.h',
> >      'request.h',
> >      'signal.h',
> > @@ -13,5 +12,14 @@ libcamera_api = files([
> >      'timer.h',
> >  ])
> >  
> > +gen_header = join_paths(meson.current_source_dir(), 'gen-header.sh')
> > +
> > +custom_target('gen-header',
> > +	      input: meson.current_source_dir(),
> > +              output: 'libcamera.h',
> > +	      command: [gen_header, '@INPUT@', '@OUTPUT@'],
> > +	      install: true,
> > +	      install_dir: 'include/libcamera')
> > +
> 
> Hrm... should this rebuild if libcamera_api changes at all ?

It should, but from my tests this is already ensured indirectly.
Changing libcamera_api changes meson.build, which triggers a
regeneration of all the related ninja files. As the timestamp of the
ninja files changes, they rebuild all the rules they contain.

> Also - Note that the following warning has appeared in my build with
> this patch applied:
> 
> 
> WARNING: Custom target input '.../libcamera/include/libcamera' can't be
> converted to File object(s).
> This will become a hard error in the future.

Which version of meson are you using ?

> >  install_headers(libcamera_api,
> >                  subdir : 'libcamera')

-- 
Regards,

Laurent Pinchart