[libcamera-devel] [PATCH v3 17/18] py: generate pixel formats list

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Wed, May 18, 2022 at 04:13:28PM +0300, Tomi Valkeinen wrote:
> Generate a list of pixel formats under "libcamera.formats".
> 
> I'm not super happy about this solution, as the user can change the
> formats (libcamera.formats.XRGB8888 = None) and, for some reason,

I won't make it a blocker for this patch, but is there a way this could
be fixed ?

> pybind11-stubgen doesn't produce stubs for this.
> 
> However, other than the two issues above, it works, and I haven't
> figured out a better way.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ideasonboard.com>
> ---
>  src/py/libcamera/gen-py-formats.py           | 56 ++++++++++++++++++++
>  src/py/libcamera/meson.build                 | 12 +++++
>  src/py/libcamera/py_formats_generated.cpp.in | 21 ++++++++
>  src/py/libcamera/py_main.cpp                 |  3 ++
>  4 files changed, 92 insertions(+)
>  create mode 100755 src/py/libcamera/gen-py-formats.py
>  create mode 100644 src/py/libcamera/py_formats_generated.cpp.in
> 
> diff --git a/src/py/libcamera/gen-py-formats.py b/src/py/libcamera/gen-py-formats.py
> new file mode 100755
> index 00000000..72565a25
> --- /dev/null
> +++ b/src/py/libcamera/gen-py-formats.py
> @@ -0,0 +1,56 @@
> +#!/usr/bin/env python3
> +# SPDX-License-Identifier: GPL-2.0-or-later
> +#
> +# Generate Python format definitions from YAML
> +
> +import argparse
> +import string
> +import sys
> +import yaml
> +
> +
> +def generate(formats):
> +    fmts = []
> +
> +    for format in formats:
> +        name, format = format.popitem()
> +        fmts.append(f'formats.attr("{name}") = &libcamera::formats::{name};')
> +
> +    return {'formats': '\n'.join(fmts)}
> +
> +
> +def fill_template(template, data):
> +    with open(template, encoding='utf-8') as f:
> +        template = f.read()
> +
> +    template = string.Template(template)
> +    return template.substitute(data)
> +
> +
> +def main(argv):
> +    parser = argparse.ArgumentParser()
> +    parser.add_argument('-o', dest='output', metavar='file', type=str,
> +                        help='Output file name. Defaults to standard output if not specified.')
> +    parser.add_argument('input', type=str,
> +                        help='Input file name.')
> +    parser.add_argument('template', type=str,
> +                        help='Template file name.')
> +    args = parser.parse_args(argv[1:])
> +
> +    with open(args.input, encoding='utf-8') as f:
> +        formats = yaml.safe_load(f)['formats']
> +
> +    data = generate(formats)
> +    data = fill_template(args.template, data)
> +
> +    if args.output:
> +        with open(args.output, 'w', encoding='utf-8') as f:
> +            f.write(data)
> +    else:
> +        sys.stdout.write(data)
> +
> +    return 0
> +
> +
> +if __name__ == '__main__':
> +    sys.exit(main(sys.argv))
> diff --git a/src/py/libcamera/meson.build b/src/py/libcamera/meson.build
> index a3388c63..0a7b65f3 100644
> --- a/src/py/libcamera/meson.build
> +++ b/src/py/libcamera/meson.build
> @@ -30,6 +30,18 @@ pycamera_sources += custom_target('py_gen_controls',
>                                    output : ['py_control_enums_generated.cpp'],
>                                    command : [gen_py_control_enums, '-o', '@OUTPUT@', '@INPUT@'])
>  
> +gen_py_formats_input_files = files([
> +    '../../libcamera/formats.yaml',
> +    'py_formats_generated.cpp.in',
> +])
> +
> +gen_py_formats = files('gen-py-formats.py')
> +
> +pycamera_sources += custom_target('py_gen_formats',
> +                                  input : gen_py_formats_input_files,
> +                                  output : ['py_formats_generated.cpp'],
> +                                  command : [gen_py_formats, '-o', '@OUTPUT@', '@INPUT@'])
> +
>  pycamera_deps = [
>      libcamera_public,
>      py3_dep,
> diff --git a/src/py/libcamera/py_formats_generated.cpp.in b/src/py/libcamera/py_formats_generated.cpp.in
> new file mode 100644
> index 00000000..1100c024
> --- /dev/null
> +++ b/src/py/libcamera/py_formats_generated.cpp.in
> @@ -0,0 +1,21 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + * Copyright (C) 2022, Tomi Valkeinen <tomi.valkeinen at ideasonboard.com>
> + *
> + * Python bindings - Auto-generated formats
> + *
> + * This file is auto-generated. Do not edit.
> + */
> +
> +#include <libcamera/formats.h>
> +
> +#include <pybind11/smart_holder.h>
> +
> +namespace py = pybind11;
> +
> +void init_py_formats_generated(py::module& m)
> +{
> +auto formats = m.def_submodule("formats");
> +
> +${formats}

Could you indent this ? It's nicer to keep generated files readable.

Apart from that,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> +}
> diff --git a/src/py/libcamera/py_main.cpp b/src/py/libcamera/py_main.cpp
> index 1d941160..e7066841 100644
> --- a/src/py/libcamera/py_main.cpp
> +++ b/src/py/libcamera/py_main.cpp
> @@ -132,6 +132,7 @@ static void handleRequestCompleted(Request *req)
>  
>  void init_py_enums(py::module &m);
>  void init_py_control_enums_generated(py::module &m);
> +void init_py_formats_generated(py::module &m);
>  void init_py_geometry(py::module &m);
>  
>  PYBIND11_MODULE(_libcamera, m)
> @@ -171,6 +172,8 @@ PYBIND11_MODULE(_libcamera, m)
>  	auto pyColorSpaceRange = py::enum_<ColorSpace::Range>(pyColorSpace, "Range");
>  	auto pyPixelFormat = py::class_<PixelFormat>(m, "PixelFormat");
>  
> +	init_py_formats_generated(m);
> +
>  	/* Global functions */
>  	m.def("log_set_level", &logSetLevel);
>  

-- 
Regards,

Laurent Pinchart