export-dmabuf: add basic and incomplete implementation

include/wlr/types/wlr_export_dmabuf_v1.h

+#ifndef WLR_TYPES_WLR_EXPORT_DMABUF_V1_H
+#define WLR_TYPES_WLR_EXPORT_DMABUF_V1_H
+
+#include <wayland-server.h>
+
+struct wlr_export_dmabuf_manager_v1;
+
+struct wlr_export_dmabuf_frame_v1 {
+	struct wl_resource *resource;
+	struct wlr_export_dmabuf_manager_v1 *manager;
+	struct wl_list link;
+
+	struct wlr_output *output;
+};
+
+struct wlr_export_dmabuf_manager_v1 {
+	struct wl_global *global;
+	struct wl_list resources;
+	struct wl_list frames;
+
+	struct wl_listener display_destroy;
+
+	struct {
+		struct wl_signal destroy;
+	} events;
+};
+
+struct wlr_export_dmabuf_manager_v1 *wlr_export_dmabuf_manager_v1_create(
+	struct wl_display *display);
+void wlr_export_dmabuf_manager_v1_destroy(
+	struct wlr_export_dmabuf_manager_v1 *manager);
+
+#endif

protocol/meson.build

@@ -39,8 +39,9 @@ protocols = [
 	'screenshooter.xml',
 	'server-decoration.xml',
 	'virtual-keyboard-unstable-v1.xml',
-	'wlr-layer-shell-unstable-v1.xml',
+	'wlr-export-dmabuf-unstable-v1.xml',
 	'wlr-input-inhibitor-unstable-v1.xml',
+	'wlr-layer-shell-unstable-v1.xml',
 ]
 
 client_protocols = [

types/meson.build

@@ -22,6 +22,7 @@ lib_wlr_types = static_library(
 		'wlr_box.c',
 		'wlr_compositor.c',
 		'wlr_cursor.c',
+		'wlr_export_dmabuf_v1.c',
 		'wlr_gamma_control.c',
 		'wlr_idle_inhibit_v1.c',
 		'wlr_idle.c',

types/wlr_export_dmabuf_v1.c

+#include <assert.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <wlr/types/wlr_export_dmabuf_v1.h>
+#include <wlr/types/wlr_linux_dmabuf.h>
+#include <wlr/types/wlr_output.h>
+#include "wlr-export-dmabuf-unstable-v1-protocol.h"
+
+#define EXPORT_DMABUF_MANAGER_VERSION 1
+
+
+static const struct zwlr_export_dmabuf_frame_v1_interface frame_impl;
+
+static struct wlr_export_dmabuf_frame_v1 *frame_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&zwlr_export_dmabuf_frame_v1_interface, &frame_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static void frame_handle_destroy(struct wl_client *client,
+		struct wl_resource *resource) {
+	wl_resource_destroy(resource);
+}
+
+static const struct zwlr_export_dmabuf_frame_v1_interface frame_impl = {
+	.destroy = frame_handle_destroy,
+};
+
+static void frame_handle_resource_destroy(struct wl_resource *resource) {
+	struct wlr_export_dmabuf_frame_v1 *frame = frame_from_resource(resource);
+	wl_list_remove(&frame->link);
+	free(frame);
+}
+
+
+static const struct zwlr_export_dmabuf_manager_v1_interface manager_impl;
+
+static struct wlr_export_dmabuf_manager_v1 *manager_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&zwlr_export_dmabuf_manager_v1_interface, &manager_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static void manager_handle_capture_client(struct wl_client *client,
+		struct wl_resource *manager_resource, uint32_t id,
+		uint32_t client_id, int32_t overlay_cursor) {
+	// TODO
+}
+
+static void manager_handle_capture_output(struct wl_client *client,
+		struct wl_resource *manager_resource, uint32_t id,
+		struct wl_resource *output_resource) {
+	struct wlr_export_dmabuf_manager_v1 *manager =
+		manager_from_resource(manager_resource);
+	struct wlr_output *output = wlr_output_from_resource(output_resource);
+
+	struct wlr_export_dmabuf_frame_v1 *frame =
+		calloc(1, sizeof(struct wlr_export_dmabuf_frame_v1));
+	if (frame == NULL) {
+		wl_resource_post_no_memory(manager_resource);
+		return;
+	}
+	frame->manager = manager;
+	frame->output = output;
+
+	uint32_t version = wl_resource_get_version(manager_resource);
+	frame->resource = wl_resource_create(client,
+		&zwlr_export_dmabuf_frame_v1_interface, version, id);
+	if (frame->resource == NULL) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+	wl_resource_set_implementation(frame->resource, &frame_impl, frame,
+		frame_handle_resource_destroy);
+
+	wl_list_insert(&manager->frames, &frame->link);
+
+	struct wlr_dmabuf_buffer_attribs attribs;
+	if (!wlr_output_export_dmabuf(output, &attribs)) {
+		zwlr_export_dmabuf_frame_v1_send_abort(frame->resource);
+		return;
+	}
+
+	// TODO: multiple layers support
+
+	uint32_t frame_flags = 0;
+	uint32_t mod_high = attribs.modifier[0] >> 32;
+	uint32_t mod_low = attribs.modifier[0];
+
+	zwlr_export_dmabuf_frame_v1_send_frame(frame->resource,
+		output->width, output->height, output->scale, output->transform,
+		attribs.flags, frame_flags, mod_high, mod_low, attribs.n_planes, 1);
+
+	zwlr_export_dmabuf_frame_v1_send_dma_layer(frame->resource, 0,
+		attribs.format, 1);
+
+	for (int i = 0; i < attribs.n_planes; ++i) {
+		// TODO: what to do if the kernel doesn't support seek on buffer
+		off_t size = lseek(attribs.fd[i], 0, SEEK_END);
+
+		zwlr_export_dmabuf_frame_v1_send_dma_object(frame->resource, i,
+			attribs.fd[i], size);
+		zwlr_export_dmabuf_frame_v1_send_dma_plane(frame->resource, i, 0, i,
+			attribs.offset[i], attribs.stride[i]);
+	}
+
+	// TODO: wait for the frame to be ready
+	// TODO: timestamps
+	zwlr_export_dmabuf_frame_v1_send_ready(frame->resource, 0, 0, 0);
+}
+
+static const struct zwlr_export_dmabuf_manager_v1_interface manager_impl = {
+	.capture_client = manager_handle_capture_client,
+	.capture_output = manager_handle_capture_output,
+};
+
+static void manager_handle_resource_destroy(struct wl_resource *resource) {
+	wl_list_remove(wl_resource_get_link(resource));
+}
+
+static void manager_bind(struct wl_client *client, void *data, uint32_t version,
+		uint32_t id) {
+	struct wlr_export_dmabuf_manager_v1 *manager = data;
+
+	struct wl_resource *resource = wl_resource_create(client,
+		&zwlr_export_dmabuf_manager_v1_interface, version, id);
+	if (resource == NULL) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+	wl_resource_set_implementation(resource, &manager_impl, manager,
+		manager_handle_resource_destroy);
+
+	wl_list_insert(&manager->resources, wl_resource_get_link(resource));
+}
+
+static void handle_display_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_export_dmabuf_manager_v1 *manager =
+		wl_container_of(listener, manager, display_destroy);
+	wlr_export_dmabuf_manager_v1_destroy(manager);
+}
+
+struct wlr_export_dmabuf_manager_v1 *wlr_export_dmabuf_manager_v1_create(
+		struct wl_display *display) {
+	struct wlr_export_dmabuf_manager_v1 *manager =
+		calloc(1, sizeof(struct wlr_export_dmabuf_manager_v1));
+	if (manager == NULL) {
+		return NULL;
+	}
+	wl_list_init(&manager->resources);
+	wl_list_init(&manager->frames);
+
+	manager->global = wl_global_create(display,
+		&zwlr_export_dmabuf_manager_v1_interface, EXPORT_DMABUF_MANAGER_VERSION,
+		manager, manager_bind);
+	if (manager->global == NULL) {
+		free(manager);
+		return NULL;
+	}
+
+	manager->display_destroy.notify = handle_display_destroy;
+	wl_display_add_destroy_listener(display, &manager->display_destroy);
+
+	return manager;
+}
+
+void wlr_export_dmabuf_manager_v1_destroy(
+		struct wlr_export_dmabuf_manager_v1 *manager) {
+	if (manager == NULL) {
+		return;
+	}
+	wl_list_remove(&manager->display_destroy.link);
+	wl_global_destroy(manager->global);
+	struct wl_resource *resource, *resource_tmp;
+	wl_resource_for_each_safe(resource, resource_tmp, &manager->resources) {
+		wl_resource_destroy(resource);
+	}
+	struct wlr_export_dmabuf_frame_v1 *frame, *frame_tmp;
+	wl_list_for_each_safe(frame, frame_tmp, &manager->frames, link) {
+		wl_resource_destroy(frame->resource);
+	}
+	free(manager);
+}