[libcamera-devel] [RFC PATCH] ipa: meson: Install mojom generated headers to include paths

[Kieran Bingham]

Hi Umang,

On 28/04/2021 14:33, Umang Jain wrote:
> Generated IPA headers from mojom files need to be installed sy
> $INCLUDE_PATH in order to be available system-wide. Without this,
> out-of-tree IPAs won't be able to link and build themselves.
> 
> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
> ---
> Marked as RFC to discuss:
> - Whether it makes sense to provide -ipa_serializer.h
>   and -ipa_proxy.h system-wide too? I am not 100%s sure yet.

I don't think it makes sense to install the serializer and proxy
headers. Those are used as part of the IPC internals I believe.



> ---
>  include/libcamera/ipa/meson.build | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/include/libcamera/ipa/meson.build b/include/libcamera/ipa/meson.build
> index 2d72c1fc..096bd4dd 100644
> --- a/include/libcamera/ipa/meson.build
> +++ b/include/libcamera/ipa/meson.build
> @@ -11,6 +11,8 @@ install_headers(libcamera_ipa_headers,
>  
>  libcamera_generated_ipa_headers = []
>  
> +generated_ipa_headers_include_path = join_paths(get_option('prefix'),'include',
> +                                                libcamera_include_dir, 'ipa')

Where possible, this should be factored out so the common parts are
shared with the installation of the libcamera_ipa_headers.

However that uses install_headers() which we can't use directly on the
custom_target it seems.

I would create at the top of the file

libcamera_ipa_include_dir = libcamera_include_dir / 'ipa'

and use that for the install_headers.

Somewhat frustratingly we likely then have to use the following for the
install_dir, as 'install_headers' would otherwise have prefixed 'include':

	install : true,
	install_dir : 'include' / libcamera_ipa_include_dir


>  #
>  # Prepare IPA/IPC generation components
>  #
> @@ -31,6 +33,8 @@ libcamera_generated_ipa_headers += custom_target('core_ipa_interface_h',
>                    input : ipa_mojom_core,
>                    output : 'core_ipa_interface.h',
>                    depends : mojom_templates,
> +                  install: true,
> +                  install_dir: generated_ipa_headers_include_path,
>                    command : [
>                        mojom_generator, 'generate',
>                        '-g', 'libcamera',
> @@ -45,6 +49,8 @@ libcamera_generated_ipa_headers += custom_target('core_ipa_serializer_h',
>                    input : ipa_mojom_core,
>                    output : 'core_ipa_serializer.h',
>                    depends : mojom_templates,
> +                  install: true,
> +                  install_dir: generated_ipa_headers_include_path,
>                    command : [
>                        mojom_generator, 'generate',
>                        '-g', 'libcamera',
> @@ -93,6 +99,8 @@ foreach file : ipa_mojom_files
>                             input : mojom,
>                             output : name + '_ipa_interface.h',
>                             depends : mojom_templates,
> +                           install: true,
> +                           install_dir: generated_ipa_headers_include_path,


Make sure you have a space around both sides of the ':' to match the
existing styles.

Presumably, this is the only header that needs to actually be installed now?
But it will need checking.

--
Kieran


>                             command : [
>                                 mojom_generator, 'generate',
>                                 '-g', 'libcamera',
> @@ -107,6 +115,8 @@ foreach file : ipa_mojom_files
>                                 input : mojom,
>                                 output : name + '_ipa_serializer.h',
>                                 depends : mojom_templates,
> +                               install: true,
> +                               install_dir: generated_ipa_headers_include_path,
>                                 command : [
>                                     mojom_generator, 'generate',
>                                     '-g', 'libcamera',
> @@ -121,6 +131,8 @@ foreach file : ipa_mojom_files
>                                   input : mojom,
>                                   output : name + '_ipa_proxy.h',
>                                   depends : mojom_templates,
> +                                 install: true,
> +                                 install_dir: generated_ipa_headers_include_path,
>                                   command : [
>                                       mojom_generator, 'generate',
>                                       '-g', 'libcamera',
> 

-- 
Regards
--
Kieran