text: #include <assert.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <wlr/interfaces/wlr_output.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"
  #include <wlr/util/log.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);
  	wl_list_remove(&frame->output_swap_buffers.link);
  	wlr_dmabuf_attributes_finish(&frame->attribs);
  	free(frame);
  }
  
  static void frame_output_handle_swap_buffers(struct wl_listener *listener,
  		void *data) {
  	struct wlr_export_dmabuf_frame_v1 *frame =
  		wl_container_of(listener, frame, output_swap_buffers);
  	struct wlr_output_event_swap_buffers *event = data;
  
  	wl_list_remove(&frame->output_swap_buffers.link);
  	wl_list_init(&frame->output_swap_buffers.link);
  
  	time_t tv_sec = event->when->tv_sec;
  	uint32_t tv_sec_hi = (sizeof(tv_sec) > 4) ? tv_sec >> 32 : 0;
  	uint32_t tv_sec_lo = tv_sec & 0xFFFFFFFF;
  	zwlr_export_dmabuf_frame_v1_send_ready(frame->resource,
  		tv_sec_hi, tv_sec_lo, event->when->tv_nsec);
  }
  
  
  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_output(struct wl_client *client,
  		struct wl_resource *manager_resource, uint32_t id,
  		int32_t overlay_cursor, 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;
  	wl_list_init(&frame->output_swap_buffers.link);
  
  	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);
  		free(frame);
  		return;
  	}
  	wl_resource_set_implementation(frame->resource, &frame_impl, frame,
  		frame_handle_resource_destroy);
  
  	wl_list_insert(&manager->frames, &frame->link);
  
  	if (!output->impl->export_dmabuf) {
  		zwlr_export_dmabuf_frame_v1_send_cancel(frame->resource,
  			ZWLR_EXPORT_DMABUF_FRAME_V1_CANCEL_REASON_PERMANENT);
  		return;
  	}
  
  	struct wlr_dmabuf_attributes *attribs = &frame->attribs;
  	if (!wlr_output_export_dmabuf(output, attribs)) {
  		zwlr_export_dmabuf_frame_v1_send_cancel(frame->resource,
  			ZWLR_EXPORT_DMABUF_FRAME_V1_CANCEL_REASON_TEMPORARY);
  		return;
  	}
  
  	uint32_t frame_flags = ZWLR_EXPORT_DMABUF_FRAME_V1_FLAGS_TRANSIENT;
  	uint32_t mod_high = attribs->modifier >> 32;
  	uint32_t mod_low = attribs->modifier & 0xFFFFFFFF;
  
  	zwlr_export_dmabuf_frame_v1_send_frame(frame->resource,
  		output->width, output->height, 0, 0, attribs->flags, frame_flags,
  		attribs->format, mod_high, mod_low, attribs->n_planes);
  
  	for (int i = 0; i < attribs->n_planes; ++i) {
  		off_t size = lseek(attribs->fd[i], 0, SEEK_END);
  
  		zwlr_export_dmabuf_frame_v1_send_object(frame->resource, i,
  			attribs->fd[i], size, attribs->offset[i], attribs->stride[i], i);
  	}
  
  	wl_list_remove(&frame->output_swap_buffers.link);
  	wl_signal_add(&output->events.swap_buffers, &frame->output_swap_buffers);
  	frame->output_swap_buffers.notify = frame_output_handle_swap_buffers;
  }
  
  static const struct zwlr_export_dmabuf_manager_v1_interface manager_impl = {
  	.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);
  }
  