wayland: generalize wayland-protocols code generation

Make it easy to add a new protocol to the list without duplicating
logic.

Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Eric Engestrom <eric@igalia.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22682>

meson.build

@@ -1913,10 +1913,6 @@ if with_platform_wayland
     dep_wayland_egl = dependency('wayland-egl-backend', version : '>= 3')
     dep_wayland_egl_headers = dep_wayland_egl.partial_dependency(compile_args : true)
   endif
-  wayland_dmabuf_xml = join_paths(
-    dep_wl_protocols.get_variable(pkgconfig : 'pkgdatadir'), 'unstable',
-    'linux-dmabuf', 'linux-dmabuf-unstable-v1.xml'
-  )
   pre_args += '-DWL_HIDE_DEPRECATED'
 endif
 

src/egl/meson.build

@@ -129,11 +129,8 @@ if with_dri2
     deps_for_egl += [dep_wayland_client, dep_wayland_server, dep_wayland_egl_headers]
     link_for_egl += libwayland_drm
     files_egl += files('drivers/dri2/platform_wayland.c')
-    files_egl += [
-      linux_dmabuf_unstable_v1_protocol_c,
-      linux_dmabuf_unstable_v1_client_protocol_h,
-      wayland_drm_client_protocol_h,
-    ]
+    files_egl += wp_files['linux-dmabuf-unstable-v1']
+    files_egl += [wayland_drm_client_protocol_h]
     incs_for_egl += include_directories('wayland/wayland-drm')
   endif
   if with_platform_android

src/egl/wayland/wayland-drm/meson.build

@@ -57,16 +57,23 @@ libwayland_drm = static_library(
 #
 # Moving these to a src/wsi/ was suggested but shot down, so put these
 # here for now as the maybe-least-bad solution.
-linux_dmabuf_unstable_v1_protocol_c = custom_target(
-  'linux-dmabuf-unstable-v1-protocol.c',
-  input : wayland_dmabuf_xml,
-  output : 'linux-dmabuf-unstable-v1-protocol.c',
-  command : [prog_wl_scanner, wl_scanner_arg, '@INPUT@', '@OUTPUT@'],
-)
-
-linux_dmabuf_unstable_v1_client_protocol_h = custom_target(
-  'linux-dmabuf-unstable-v1-client-protocol.h',
-  input : wayland_dmabuf_xml,
-  output : 'linux-dmabuf-unstable-v1-client-protocol.h',
-  command : [prog_wl_scanner, 'client-header', '@INPUT@', '@OUTPUT@'],
-)
+wp_dir = dep_wl_protocols.get_variable(pkgconfig : 'pkgdatadir')
+wp_protos = {
+  'linux-dmabuf-unstable-v1': 'unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml',
+}
+wp_files = {}
+foreach name, xml : wp_protos
+  code = custom_target(
+    name + '-protocol.c',
+    input : join_paths(wp_dir, xml),
+    output : name + '-protocol.c',
+    command : [prog_wl_scanner, wl_scanner_arg, '@INPUT@', '@OUTPUT@'],
+  )
+  header = custom_target(
+    name + '-client-protocol.h',
+    input : join_paths(wp_dir, xml),
+    output : name + '-client-protocol.h',
+    command : [prog_wl_scanner, 'client-header', '@INPUT@', '@OUTPUT@'],
+  )
+  wp_files += { name: [code, header] }
+endforeach

src/vulkan/wsi/meson.build

@@ -31,10 +31,7 @@ endif
 
 if with_platform_wayland
   files_vulkan_wsi += files('wsi_common_wayland.c')
-  files_vulkan_wsi += [
-    linux_dmabuf_unstable_v1_client_protocol_h,
-    linux_dmabuf_unstable_v1_protocol_c,
-  ]
+  files_vulkan_wsi += wp_files['linux-dmabuf-unstable-v1']
 endif
 
 if with_platform_windows