gl-renderer: Replace display-create args with struct

gl_rendererer's output_create has a lot of arguments now. Add a
structure for the options to make it more clear what is what.
This is in preparation for adding bare-integer arguments which are ripe
for confusion when passing positional arguments.

Signed-off-by: Daniel Stone <daniels@collabora.com>

libweston/backend-drm/drm-gbm.c

@@ -98,18 +98,19 @@ drm_backend_create_gl_renderer(struct drm_backend *b)
 		fallback_format_for(b->gbm_format),
 		0,
 	};
-	unsigned n_formats = 2;
+	struct gl_renderer_display_options options = {
+		.egl_platform = EGL_PLATFORM_GBM_KHR,
+		.egl_native_display = b->gbm,
+		.egl_surface_type = EGL_WINDOW_BIT,
+		.drm_formats = format,
+		.drm_formats_count = 2,
+	};
 
 	if (format[1])
-		n_formats = 3;
-	if (gl_renderer->display_create(b->compositor,
-					EGL_PLATFORM_GBM_KHR,
-					(void *)b->gbm,
-					EGL_WINDOW_BIT,
-					format,
-					n_formats) < 0) {
+		options.drm_formats_count = 3;
+
+	if (gl_renderer->display_create(b->compositor, &options) < 0)
 		return -1;
-	}
 
 	return 0;
 }

libweston/backend-headless/headless.c

@@ -387,20 +387,19 @@ headless_destroy(struct weston_compositor *ec)
 static int
 headless_gl_renderer_init(struct headless_backend *b)
 {
+	const struct gl_renderer_display_options options = {
+		.egl_platform = EGL_PLATFORM_SURFACELESS_MESA,
+		.egl_native_display = EGL_DEFAULT_DISPLAY,
+		.egl_surface_type = EGL_PBUFFER_BIT,
+		.drm_formats = headless_formats,
+		.drm_formats_count = ARRAY_LENGTH(headless_formats),
+	};
+
 	b->glri = weston_load_module("gl-renderer.so", "gl_renderer_interface");
 	if (!b->glri)
 		return -1;
 
-	if (b->glri->display_create(b->compositor,
-				    EGL_PLATFORM_SURFACELESS_MESA,
-				    EGL_DEFAULT_DISPLAY,
-				    EGL_PBUFFER_BIT,
-				    headless_formats,
-				    ARRAY_LENGTH(headless_formats)) < 0) {
-		return -1;
-	}
-
-	return 0;
+	return b->glri->display_create(b->compositor, &options);
 }
 
 static const struct weston_windowed_output_api api = {

libweston/backend-wayland/wayland.c

@@ -2773,12 +2773,14 @@ wayland_backend_create(struct weston_compositor *compositor,
 	}
 
 	if (!b->use_pixman) {
-		if (gl_renderer->display_create(compositor,
-						EGL_PLATFORM_WAYLAND_KHR,
-						b->parent.wl_display,
-						EGL_WINDOW_BIT,
-						wayland_formats,
-						ARRAY_LENGTH(wayland_formats)) < 0) {
+		const struct gl_renderer_display_options options = {
+			.egl_platform = EGL_PLATFORM_WAYLAND_KHR,
+			.egl_native_display = b->parent.wl_display,
+			.egl_surface_type = EGL_WINDOW_BIT,
+			.drm_formats = wayland_formats,
+			.drm_formats_count = ARRAY_LENGTH(wayland_formats),
+		};
+		if (gl_renderer->display_create(compositor, &options) < 0) {
 			weston_log("Failed to initialize the GL renderer; "
 				   "falling back to pixman.\n");
 			b->use_pixman = true;

libweston/backend-x11/x11.c

@@ -1794,20 +1794,20 @@ x11_destroy(struct weston_compositor *ec)
 static int
 init_gl_renderer(struct x11_backend *b)
 {
-	int ret;
+	const struct gl_renderer_display_options options = {
+		.egl_platform = EGL_PLATFORM_X11_KHR,
+		.egl_native_display = b->dpy,
+		.egl_surface_type = EGL_WINDOW_BIT,
+		.drm_formats = x11_formats,
+		.drm_formats_count = ARRAY_LENGTH(x11_formats),
+	};
 
 	gl_renderer = weston_load_module("gl-renderer.so",
 					 "gl_renderer_interface");
 	if (!gl_renderer)
 		return -1;
 
-	ret = gl_renderer->display_create(b->compositor, EGL_PLATFORM_X11_KHR,
-					  (void *) b->dpy,
-					  EGL_WINDOW_BIT,
-					  x11_formats,
-					  ARRAY_LENGTH(x11_formats));
-
-	return ret;
+	return gl_renderer->display_create(b->compositor, &options);
 }
 
 static const struct weston_windowed_output_api api = {

libweston/renderer-gl/gl-renderer.c

@@ -3374,11 +3374,7 @@ gl_renderer_create_pbuffer_surface(struct gl_renderer *gr) {
 
 static int
 gl_renderer_display_create(struct weston_compositor *ec,
-			   EGLenum platform,
-			   void *native_display,
-			   EGLint egl_surface_type,
-			   const uint32_t *drm_formats,
-			   unsigned drm_formats_count)
+			   const struct gl_renderer_display_options *options)
 {
 	struct gl_renderer *gr;
 
@@ -3386,7 +3382,7 @@ gl_renderer_display_create(struct weston_compositor *ec,
 	if (gr == NULL)
 		return -1;
 
-	gr->platform = platform;
+	gr->platform = options->egl_platform;
 
 	if (gl_renderer_setup_egl_client_extensions(gr) < 0)
 		goto fail;
@@ -3401,7 +3397,7 @@ gl_renderer_display_create(struct weston_compositor *ec,
 		gl_renderer_surface_get_content_size;
 	gr->base.surface_copy_content = gl_renderer_surface_copy_content;
 
-	if (gl_renderer_setup_egl_display(gr, native_display) < 0)
+	if (gl_renderer_setup_egl_display(gr, options->egl_native_display) < 0)
 		goto fail;
 
 	log_egl_info(gr->egl_display);
@@ -3412,13 +3408,16 @@ gl_renderer_display_create(struct weston_compositor *ec,
 		goto fail_with_error;
 
 	if (!gr->has_configless_context) {
+		EGLint egl_surface_type = options->egl_surface_type;
+
 		if (!gr->has_surfaceless_context)
 			egl_surface_type |= EGL_PBUFFER_BIT;
 
-		gr->egl_config = gl_renderer_get_egl_config(gr,
+		gr->egl_config =
+			gl_renderer_get_egl_config(gr,
 						   egl_surface_type,
-							    drm_formats,
-							    drm_formats_count);
+						   options->drm_formats,
+						   options->drm_formats_count);
 		if (gr->egl_config == EGL_NO_CONFIG_KHR) {
 			weston_log("failed to choose EGL config\n");
 			goto fail_terminate;

libweston/renderer-gl/gl-renderer.h

@@ -58,18 +58,30 @@ enum gl_renderer_border_side {
 	GL_RENDERER_BORDER_BOTTOM = 3,
 };
 
+/**
+ * Options passed to the \c display_create method of the GL renderer interface.
+ *
+ * \see struct gl_renderer_interface
+ */
+struct gl_renderer_display_options {
+	/** The EGL platform identifier */
+	EGLenum egl_platform;
+	/** The native display corresponding to the given EGL platform */
+	void *egl_native_display;
+	/** EGL_SURFACE_TYPE bits for the base EGLConfig */
+	EGLint egl_surface_type;
+	/** Array of DRM pixel formats acceptable for the base EGLConfig */
+	const uint32_t *drm_formats;
+	/** The \c drm_formats array length */
+	unsigned drm_formats_count;
+};
+
 struct gl_renderer_interface {
 	/**
 	 * Initialize GL-renderer with the given EGL platform and native display
 	 *
 	 * \param ec The weston_compositor where to initialize.
-	 * \param platform The EGL platform identifier.
-	 * \param native_display The native display corresponding to the given
-	 * EGL platform.
-	 * \param egl_surface_type EGL_SURFACE_TYPE bits for the base EGLConfig.
-	 * \param drm_formats Array of DRM pixel formats that are acceptable
-	 * for the base EGLConfig.
-	 * \param drm_formats_count The drm_formats array length.
+	 * \param options The options struct describing display configuration
 	 * \return 0 on success, -1 on failure.
 	 *
 	 * This function creates an EGLDisplay and initializes it. It also
@@ -96,11 +108,7 @@ struct gl_renderer_interface {
 	 * DRM format.
 	 */
 	int (*display_create)(struct weston_compositor *ec,
-			      EGLenum platform,
-			      void *native_display,
-			      EGLint egl_surface_type,
-			      const uint32_t *drm_formats,
-			      unsigned drm_formats_count);
+			      const struct gl_renderer_display_options *options);
 
 	/**
 	 * Attach GL-renderer to the output with a native window