Merge pull request #937 from emersion/reorder-data-device

data-device: split into multiple files

7 files changed, 1270 insertions, 1204 deletions

diff --git a/include/types/wlr_data_device.h b/include/types/wlr_data_device.h
new file mode 100644
index 00000000..4aa53dc0
--- /dev/null
+++ b/include/types/wlr_data_device.h
@@ -0,0 +1,32 @@
+#ifndef TYPES_WLR_DATA_DEVICE_H
+#define TYPES_WLR_DATA_DEVICE_H
+
+#include <wayland-server.h>
+
+#define DATA_DEVICE_ALL_ACTIONS (WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY | \
+	WL_DATA_DEVICE_MANAGER_DND_ACTION_MOVE | \
+	WL_DATA_DEVICE_MANAGER_DND_ACTION_ASK)
+
+struct wlr_client_data_source {
+	struct wlr_data_source source;
+	struct wlr_data_source_impl impl;
+	struct wl_resource *resource;
+};
+
+struct wlr_data_offer *data_offer_create(struct wl_client *client,
+	struct wlr_data_source *source, uint32_t version);
+void data_offer_update_action(struct wlr_data_offer *offer);
+
+struct wlr_client_data_source *client_data_source_create(
+	struct wl_client *client, uint32_t version, uint32_t id);
+struct wlr_client_data_source *client_data_source_from_resource(
+	struct wl_resource *resource);
+struct wlr_data_offer *data_source_send_offer(struct wlr_data_source *source,
+	struct wlr_seat_client *target);
+void data_source_notify_finish(struct wlr_data_source *source);
+
+bool seat_client_start_drag(struct wlr_seat_client *client,
+	struct wlr_data_source *source, struct wlr_surface *icon_surface,
+	struct wlr_surface *origin, uint32_t serial);
+
+#endif
diff --git a/types/data_device/wlr_data_device.c b/types/data_device/wlr_data_device.c
new file mode 100644
index 00000000..fffb2f1b
--- /dev/null
+++ b/types/data_device/wlr_data_device.c
@@ -0,0 +1,248 @@
+#define _XOPEN_SOURCE 700
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <wayland-server.h>
+#include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/util/log.h>
+#include "types/wlr_data_device.h"
+#include "util/signal.h"
+
+static const struct wl_data_device_interface data_device_impl;
+
+static struct wlr_seat_client *seat_client_from_data_device_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource, &wl_data_device_interface,
+		&data_device_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static void data_device_set_selection(struct wl_client *client,
+		struct wl_resource *device_resource,
+		struct wl_resource *source_resource, uint32_t serial) {
+	struct wlr_client_data_source *source = NULL;
+	if (source_resource != NULL) {
+		source = client_data_source_from_resource(source_resource);
+	}
+
+	struct wlr_seat_client *seat_client =
+		seat_client_from_data_device_resource(device_resource);
+
+	struct wlr_data_source *wlr_source = (struct wlr_data_source *)source;
+	wlr_seat_set_selection(seat_client->seat, wlr_source, serial);
+}
+
+static void data_device_start_drag(struct wl_client *client,
+		struct wl_resource *device_resource,
+		struct wl_resource *source_resource,
+		struct wl_resource *origin_resource, struct wl_resource *icon_resource,
+		uint32_t serial) {
+	struct wlr_seat_client *seat_client =
+		seat_client_from_data_device_resource(device_resource);
+	struct wlr_surface *origin = wlr_surface_from_resource(origin_resource);
+	struct wlr_data_source *source = NULL;
+	struct wlr_surface *icon = NULL;
+
+	if (source_resource) {
+		struct wlr_client_data_source *client_source =
+			client_data_source_from_resource(source_resource);
+		source = (struct wlr_data_source *)client_source;
+	}
+
+	if (icon_resource) {
+		icon = wlr_surface_from_resource(icon_resource);
+	}
+	if (icon) {
+		if (wlr_surface_set_role(icon, "wl_data_device-icon",
+					icon_resource, WL_DATA_DEVICE_ERROR_ROLE) < 0) {
+			return;
+		}
+	}
+
+	if (!seat_client_start_drag(seat_client, source, icon, origin, serial)) {
+		wl_resource_post_no_memory(device_resource);
+		return;
+	}
+
+	if (source) {
+		source->seat_client = seat_client;
+	}
+}
+
+static void data_device_release(struct wl_client *client,
+		struct wl_resource *resource) {
+	wl_resource_destroy(resource);
+}
+
+static const struct wl_data_device_interface data_device_impl = {
+	.start_drag = data_device_start_drag,
+	.set_selection = data_device_set_selection,
+	.release = data_device_release,
+};
+
+static void data_device_destroy(struct wl_resource *resource) {
+	wl_list_remove(wl_resource_get_link(resource));
+}
+
+
+void wlr_seat_client_send_selection(struct wlr_seat_client *seat_client) {
+	if (wl_list_empty(&seat_client->data_devices)) {
+		return;
+	}
+
+	if (seat_client->seat->selection_source) {
+		struct wlr_data_offer *offer = data_source_send_offer(
+			seat_client->seat->selection_source, seat_client);
+		if (offer == NULL) {
+			return;
+		}
+
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &seat_client->data_devices) {
+			wl_data_device_send_selection(resource, offer->resource);
+		}
+	} else {
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &seat_client->data_devices) {
+			wl_data_device_send_selection(resource, NULL);
+		}
+	}
+}
+
+static void seat_client_selection_source_destroy(
+		struct wl_listener *listener, void *data) {
+	struct wlr_seat *seat =
+		wl_container_of(listener, seat, selection_source_destroy);
+	struct wlr_seat_client *seat_client = seat->keyboard_state.focused_client;
+
+	if (seat_client && seat->keyboard_state.focused_surface) {
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &seat_client->data_devices) {
+			wl_data_device_send_selection(resource, NULL);
+		}
+	}
+
+	seat->selection_source = NULL;
+
+	wlr_signal_emit_safe(&seat->events.selection, seat);
+}
+
+void wlr_seat_set_selection(struct wlr_seat *seat,
+		struct wlr_data_source *source, uint32_t serial) {
+	if (seat->selection_source &&
+			seat->selection_serial - serial < UINT32_MAX / 2) {
+		return;
+	}
+
+	if (seat->selection_source) {
+		wl_list_remove(&seat->selection_source_destroy.link);
+		wlr_data_source_cancel(seat->selection_source);
+		seat->selection_source = NULL;
+	}
+
+	seat->selection_source = source;
+	seat->selection_serial = serial;
+
+	struct wlr_seat_client *focused_client =
+		seat->keyboard_state.focused_client;
+
+	if (focused_client) {
+		wlr_seat_client_send_selection(focused_client);
+	}
+
+	wlr_signal_emit_safe(&seat->events.selection, seat);
+
+	if (source) {
+		seat->selection_source_destroy.notify =
+			seat_client_selection_source_destroy;
+		wl_signal_add(&source->events.destroy,
+			&seat->selection_source_destroy);
+	}
+}
+
+
+static void data_device_manager_get_data_device(struct wl_client *client,
+		struct wl_resource *manager_resource, uint32_t id,
+		struct wl_resource *seat_resource) {
+	struct wlr_seat_client *seat_client =
+		wlr_seat_client_from_resource(seat_resource);
+
+	struct wl_resource *resource = wl_resource_create(client,
+		&wl_data_device_interface, wl_resource_get_version(manager_resource),
+		id);
+	if (resource == NULL) {
+		wl_resource_post_no_memory(manager_resource);
+		return;
+	}
+	wl_resource_set_implementation(resource, &data_device_impl, seat_client,
+		&data_device_destroy);
+	wl_list_insert(&seat_client->data_devices, wl_resource_get_link(resource));
+}
+
+static void data_device_manager_create_data_source(struct wl_client *client,
+		struct wl_resource *resource, uint32_t id) {
+	client_data_source_create(client, wl_resource_get_version(resource), id);
+}
+
+static const struct wl_data_device_manager_interface
+		data_device_manager_impl = {
+	.create_data_source = data_device_manager_create_data_source,
+	.get_data_device = data_device_manager_get_data_device,
+};
+
+static void data_device_manager_bind(struct wl_client *client,
+		void *data, uint32_t version, uint32_t id) {
+	struct wl_resource *resource = wl_resource_create(client,
+		&wl_data_device_manager_interface,
+		version, id);
+	if (resource == NULL) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	wl_resource_set_implementation(resource, &data_device_manager_impl,
+		NULL, NULL);
+}
+
+void wlr_data_device_manager_destroy(struct wlr_data_device_manager *manager) {
+	if (!manager) {
+		return;
+	}
+	wl_list_remove(&manager->display_destroy.link);
+	// TODO: free wl_resources
+	wl_global_destroy(manager->global);
+	free(manager);
+}
+
+static void handle_display_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_data_device_manager *manager =
+		wl_container_of(listener, manager, display_destroy);
+	wlr_data_device_manager_destroy(manager);
+}
+
+struct wlr_data_device_manager *wlr_data_device_manager_create(
+		struct wl_display *display) {
+	struct wlr_data_device_manager *manager =
+		calloc(1, sizeof(struct wlr_data_device_manager));
+	if (manager == NULL) {
+		wlr_log(L_ERROR, "could not create data device manager");
+		return NULL;
+	}
+
+	manager->global =
+		wl_global_create(display, &wl_data_device_manager_interface,
+			3, NULL, data_device_manager_bind);
+	if (!manager->global) {
+		wlr_log(L_ERROR, "could not create data device manager wl global");
+		free(manager);
+		return NULL;
+	}
+
+	manager->display_destroy.notify = handle_display_destroy;
+	wl_display_add_destroy_listener(display, &manager->display_destroy);
+
+	return manager;
+}
diff --git a/types/data_device/wlr_data_offer.c b/types/data_device/wlr_data_offer.c
new file mode 100644
index 00000000..dfaf054c
--- /dev/null
+++ b/types/data_device/wlr_data_offer.c
@@ -0,0 +1,217 @@
+#define _XOPEN_SOURCE 700
+#include <assert.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <unistd.h>
+#include <wayland-server.h>
+#include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/util/log.h>
+#include "types/wlr_data_device.h"
+#include "util/signal.h"
+
+static const struct wl_data_offer_interface data_offer_impl;
+
+static struct wlr_data_offer *data_offer_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource, &wl_data_offer_interface,
+		&data_offer_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static uint32_t data_offer_choose_action(struct wlr_data_offer *offer) {
+	uint32_t offer_actions, preferred_action = 0;
+	if (wl_resource_get_version(offer->resource) >=
+			WL_DATA_OFFER_ACTION_SINCE_VERSION) {
+		offer_actions = offer->actions;
+		preferred_action = offer->preferred_action;
+	} else {
+		offer_actions = WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY;
+	}
+
+	uint32_t source_actions;
+	if (offer->source->actions >= 0) {
+		source_actions = offer->source->actions;
+	} else {
+		source_actions = WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY;
+	}
+
+	uint32_t available_actions = offer_actions & source_actions;
+	if (!available_actions) {
+		return WL_DATA_DEVICE_MANAGER_DND_ACTION_NONE;
+	}
+
+	if (offer->source->seat_client &&
+			offer->source->compositor_action & available_actions) {
+		return offer->source->compositor_action;
+	}
+
+	// If the dest side has a preferred DnD action, use it
+	if ((preferred_action & available_actions) != 0) {
+		return preferred_action;
+	}
+
+	// Use the first found action, in bit order
+	return 1 << (ffs(available_actions) - 1);
+}
+
+void data_offer_update_action(struct wlr_data_offer *offer) {
+	if (!offer->source) {
+		return;
+	}
+
+	uint32_t action = data_offer_choose_action(offer);
+	if (offer->source->current_dnd_action == action) {
+		return;
+	}
+
+	offer->source->current_dnd_action = action;
+
+	if (offer->in_ask) {
+		return;
+	}
+
+	wlr_data_source_dnd_action(offer->source, action);
+
+	if (wl_resource_get_version(offer->resource) >=
+			WL_DATA_OFFER_ACTION_SINCE_VERSION) {
+		wl_data_offer_send_action(offer->resource, action);
+	}
+}
+
+static void data_offer_accept(struct wl_client *client,
+		struct wl_resource *resource, uint32_t serial, const char *mime_type) {
+	struct wlr_data_offer *offer = data_offer_from_resource(resource);
+
+	if (!offer->source || offer != offer->source->offer) {
+		return;
+	}
+
+	// TODO check that client is currently focused by the input device
+
+	wlr_data_source_accept(offer->source, serial, mime_type);
+}
+
+static void data_offer_receive(struct wl_client *client,
+		struct wl_resource *resource, const char *mime_type, int32_t fd) {
+	struct wlr_data_offer *offer = data_offer_from_resource(resource);
+
+	if (offer->source && offer == offer->source->offer) {
+		wlr_data_source_send(offer->source, mime_type, fd);
+	} else {
+		close(fd);
+	}
+}
+
+static void data_offer_destroy(struct wl_client *client,
+		struct wl_resource *resource) {
+	wl_resource_destroy(resource);
+}
+
+static void data_offer_finish(struct wl_client *client,
+		struct wl_resource *resource) {
+	struct wlr_data_offer *offer = data_offer_from_resource(resource);
+
+	if (!offer->source || offer->source->offer != offer) {
+		return;
+	}
+
+	data_source_notify_finish(offer->source);
+}
+
+static void data_offer_set_actions(struct wl_client *client,
+		struct wl_resource *resource, uint32_t actions,
+		uint32_t preferred_action) {
+	struct wlr_data_offer *offer = data_offer_from_resource(resource);
+
+	if (actions & ~DATA_DEVICE_ALL_ACTIONS) {
+		wl_resource_post_error(offer->resource,
+			WL_DATA_OFFER_ERROR_INVALID_ACTION_MASK,
+			"invalid action mask %x", actions);
+		return;
+	}
+
+	if (preferred_action && (!(preferred_action & actions) ||
+			__builtin_popcount(preferred_action) > 1)) {
+		wl_resource_post_error(offer->resource,
+			WL_DATA_OFFER_ERROR_INVALID_ACTION,
+			"invalid action %x", preferred_action);
+		return;
+	}
+
+	offer->actions = actions;
+	offer->preferred_action = preferred_action;
+
+	data_offer_update_action(offer);
+}
+
+static void data_offer_resource_destroy(struct wl_resource *resource) {
+	struct wlr_data_offer *offer = data_offer_from_resource(resource);
+
+	if (!offer->source) {
+		goto out;
+	}
+
+	wl_list_remove(&offer->source_destroy.link);
+
+	if (offer->source->offer != offer) {
+		goto out;
+	}
+
+	// If the drag destination has version < 3, wl_data_offer.finish
+	// won't be called, so do this here as a safety net, because
+	// we still want the version >= 3 drag source to be happy.
+	if (wl_resource_get_version(offer->resource) <
+			WL_DATA_OFFER_ACTION_SINCE_VERSION) {
+		data_source_notify_finish(offer->source);
+		offer->source->offer = NULL;
+	} else if (offer->source->impl->dnd_finish) {
+		// source->cancel can free the source
+		offer->source->offer = NULL;
+		wlr_data_source_cancel(offer->source);
+	} else {
+		offer->source->offer = NULL;
+	}
+
+out:
+	free(offer);
+}
+
+static const struct wl_data_offer_interface data_offer_impl = {
+	.accept = data_offer_accept,
+	.receive = data_offer_receive,
+	.destroy = data_offer_destroy,
+	.finish = data_offer_finish,
+	.set_actions = data_offer_set_actions,
+};
+
+static void handle_offer_source_destroyed(struct wl_listener *listener,
+		void *data) {
+	struct wlr_data_offer *offer =
+		wl_container_of(listener, offer, source_destroy);
+
+	offer->source = NULL;
+}
+
+struct wlr_data_offer *data_offer_create(struct wl_client *client,
+		struct wlr_data_source *source, uint32_t version) {
+	struct wlr_data_offer *offer = calloc(1, sizeof(struct wlr_data_offer));
+	if (offer == NULL) {
+		return NULL;
+	}
+	offer->source = source;
+
+	offer->resource = wl_resource_create(client,
+		&wl_data_offer_interface, version, 0);
+	if (offer->resource == NULL) {
+		free(offer);
+		return NULL;
+	}
+	wl_resource_set_implementation(offer->resource, &data_offer_impl, offer,
+		data_offer_resource_destroy);
+
+	offer->source_destroy.notify = handle_offer_source_destroyed;
+	wl_signal_add(&source->events.destroy, &offer->source_destroy);
+
+	return offer;
+}
diff --git a/types/data_device/wlr_data_source.c b/types/data_device/wlr_data_source.c
new file mode 100644
index 00000000..7c554d35
--- /dev/null
+++ b/types/data_device/wlr_data_source.c
@@ -0,0 +1,288 @@
+#define _XOPEN_SOURCE 700
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <wayland-server.h>
+#include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/util/log.h>
+#include "types/wlr_data_device.h"
+#include "util/signal.h"
+
+void data_source_notify_finish(struct wlr_data_source *source) {
+	assert(source->offer);
+	if (source->actions < 0) {
+		return;
+	}
+
+	if (source->offer->in_ask) {
+		wlr_data_source_dnd_action(source, source->current_dnd_action);
+	}
+
+	source->offer = NULL;
+	wlr_data_source_dnd_finish(source);
+}
+
+struct wlr_data_offer *data_source_send_offer(struct wlr_data_source *source,
+		struct wlr_seat_client *target) {
+	if (wl_list_empty(&target->data_devices)) {
+		return NULL;
+	}
+
+	uint32_t version = wl_resource_get_version(
+		wl_resource_from_link(target->data_devices.next));
+
+	struct wlr_data_offer *offer =
+		data_offer_create(target->client, source, version);
+	if (offer == NULL) {
+		return NULL;
+	}
+
+	struct wl_resource *target_resource;
+	wl_resource_for_each(target_resource, &target->data_devices) {
+		wl_data_device_send_data_offer(target_resource, offer->resource);
+	}
+
+	char **p;
+	wl_array_for_each(p, &source->mime_types) {
+		wl_data_offer_send_offer(offer->resource, *p);
+	}
+
+	source->offer = offer;
+	source->accepted = false;
+	return offer;
+}
+
+void wlr_data_source_init(struct wlr_data_source *source,
+		const struct wlr_data_source_impl *impl) {
+	assert(impl->send);
+
+	source->impl = impl;
+	wl_array_init(&source->mime_types);
+	wl_signal_init(&source->events.destroy);
+	source->actions = -1;
+}
+
+void wlr_data_source_finish(struct wlr_data_source *source) {
+	if (source == NULL) {
+		return;
+	}
+
+	wlr_signal_emit_safe(&source->events.destroy, source);
+
+	char **p;
+	wl_array_for_each(p, &source->mime_types) {
+		free(*p);
+	}
+	wl_array_release(&source->mime_types);
+}
+
+void wlr_data_source_send(struct wlr_data_source *source, const char *mime_type,
+		int32_t fd) {
+	source->impl->send(source, mime_type, fd);
+}
+
+void wlr_data_source_accept(struct wlr_data_source *source, uint32_t serial,
+		const char *mime_type) {
+	source->accepted = (mime_type != NULL);
+	if (source->impl->accept) {
+		source->impl->accept(source, serial, mime_type);
+	}
+}
+
+void wlr_data_source_cancel(struct wlr_data_source *source) {
+	if (source->impl->cancel) {
+		source->impl->cancel(source);
+	}
+}
+
+void wlr_data_source_dnd_drop(struct wlr_data_source *source) {
+	if (source->impl->dnd_drop) {
+		source->impl->dnd_drop(source);
+	}
+}
+
+void wlr_data_source_dnd_finish(struct wlr_data_source *source) {
+	if (source->impl->dnd_finish) {
+		source->impl->dnd_finish(source);
+	}
+}
+
+void wlr_data_source_dnd_action(struct wlr_data_source *source,
+		enum wl_data_device_manager_dnd_action action) {
+	source->current_dnd_action = action;
+	if (source->impl->dnd_action) {
+		source->impl->dnd_action(source, action);
+	}
+}
+
+
+static const struct wl_data_source_interface data_source_impl;
+
+struct wlr_client_data_source *client_data_source_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource, &wl_data_source_interface,
+		&data_source_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static void client_data_source_accept(struct wlr_data_source *wlr_source,
+	uint32_t serial, const char *mime_type);
+
+static struct wlr_client_data_source *client_data_source_from_wlr_data_source(
+		struct wlr_data_source *wlr_source) {
+	assert(wlr_source->impl->accept == client_data_source_accept);
+	return (struct wlr_client_data_source *)wlr_source;
+}
+
+static void client_data_source_accept(struct wlr_data_source *wlr_source,
+		uint32_t serial, const char *mime_type) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_wlr_data_source(wlr_source);
+	wl_data_source_send_target(source->resource, mime_type);
+}
+
+static void client_data_source_send(struct wlr_data_source *wlr_source,
+		const char *mime_type, int32_t fd) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_wlr_data_source(wlr_source);
+	wl_data_source_send_send(source->resource, mime_type, fd);
+	close(fd);
+}
+
+static void client_data_source_cancel(struct wlr_data_source *wlr_source) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_wlr_data_source(wlr_source);
+	wl_data_source_send_cancelled(source->resource);
+}
+
+static void client_data_source_dnd_drop(struct wlr_data_source *wlr_source) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_wlr_data_source(wlr_source);
+	assert(wl_resource_get_version(source->resource) >=
+		WL_DATA_SOURCE_DND_DROP_PERFORMED_SINCE_VERSION);
+	wl_data_source_send_dnd_drop_performed(source->resource);
+}
+
+static void client_data_source_dnd_finish(struct wlr_data_source *wlr_source) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_wlr_data_source(wlr_source);
+	assert(wl_resource_get_version(source->resource) >=
+		WL_DATA_SOURCE_DND_FINISHED_SINCE_VERSION);
+	wl_data_source_send_dnd_finished(source->resource);
+}
+
+static void client_data_source_dnd_action(struct wlr_data_source *wlr_source,
+		enum wl_data_device_manager_dnd_action action) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_wlr_data_source(wlr_source);
+	assert(wl_resource_get_version(source->resource) >=
+		WL_DATA_SOURCE_ACTION_SINCE_VERSION);
+	wl_data_source_send_action(source->resource, action);
+}
+
+static void data_source_destroy(struct wl_client *client,
+		struct wl_resource *resource) {
+	wl_resource_destroy(resource);
+}
+
+static void data_source_set_actions(struct wl_client *client,
+		struct wl_resource *resource, uint32_t dnd_actions) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_resource(resource);
+
+	if (source->source.actions >= 0) {
+		wl_resource_post_error(source->resource,
+			WL_DATA_SOURCE_ERROR_INVALID_ACTION_MASK,
+			"cannot set actions more than once");
+		return;
+	}
+
+	if (dnd_actions & ~DATA_DEVICE_ALL_ACTIONS) {
+		wl_resource_post_error(source->resource,
+			WL_DATA_SOURCE_ERROR_INVALID_ACTION_MASK,
+			"invalid action mask %x", dnd_actions);
+		return;
+	}
+
+	if (source->source.seat_client) {
+		wl_resource_post_error(source->resource,
+			WL_DATA_SOURCE_ERROR_INVALID_ACTION_MASK,
+			"invalid action change after "
+			"wl_data_device.start_drag");
+		return;
+	}
+
+	source->source.actions = dnd_actions;
+}
+
+static void data_source_offer(struct wl_client *client,
+		struct wl_resource *resource, const char *mime_type) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_resource(resource);
+
+	char **p = wl_array_add(&source->source.mime_types, sizeof(*p));
+	if (p) {
+		*p = strdup(mime_type);
+	}
+	if (!p || !*p) {
+		if (p) {
+			source->source.mime_types.size -= sizeof(*p);
+		}
+		wl_resource_post_no_memory(resource);
+	}
+}
+
+static const struct wl_data_source_interface data_source_impl = {
+	.offer = data_source_offer,
+	.destroy = data_source_destroy,
+	.set_actions = data_source_set_actions,
+};
+
+static void data_source_handle_resource_destroy(struct wl_resource *resource) {
+	struct wlr_client_data_source *source =
+		client_data_source_from_resource(resource);
+	wlr_data_source_finish(&source->source);
+	free(source);
+}
+
+struct wlr_client_data_source *client_data_source_create(
+		struct wl_client *client, uint32_t version, uint32_t id) {
+	struct wlr_client_data_source *source =
+		calloc(1, sizeof(struct wlr_client_data_source));
+	if (source == NULL) {
+		return NULL;
+	}
+
+	source->resource = wl_resource_create(client, &wl_data_source_interface,
+		version, id);
+	if (source->resource == NULL) {
+		wl_resource_post_no_memory(source->resource);
+		free(source);
+		return NULL;
+	}
+	wl_resource_set_implementation(source->resource, &data_source_impl,
+		source, data_source_handle_resource_destroy);
+
+	source->impl.accept = client_data_source_accept;
+	source->impl.send = client_data_source_send;
+	source->impl.cancel = client_data_source_cancel;
+
+	if (wl_resource_get_version(source->resource) >=
+			WL_DATA_SOURCE_DND_DROP_PERFORMED_SINCE_VERSION) {
+		source->impl.dnd_drop = client_data_source_dnd_drop;
+	}
+	if (wl_resource_get_version(source->resource) >=
+			WL_DATA_SOURCE_DND_FINISHED_SINCE_VERSION) {
+		source->impl.dnd_finish = client_data_source_dnd_finish;
+	}
+	if (wl_resource_get_version(source->resource) >=
+			WL_DATA_SOURCE_ACTION_SINCE_VERSION) {
+		source->impl.dnd_action = client_data_source_dnd_action;
+	}
+
+	wlr_data_source_init(&source->source, &source->impl);
+	return source;
+}
diff --git a/types/data_device/wlr_drag.c b/types/data_device/wlr_drag.c
new file mode 100644
index 00000000..72a5bc41
--- /dev/null
+++ b/types/data_device/wlr_drag.c
@@ -0,0 +1,481 @@
+#define _XOPEN_SOURCE 700
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <wayland-server.h>
+#include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/util/log.h>
+#include "types/wlr_data_device.h"
+#include "util/signal.h"
+
+static void drag_handle_seat_client_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_drag *drag =
+		wl_container_of(listener, drag, seat_client_destroy);
+
+	drag->focus_client = NULL;
+	wl_list_remove(&drag->seat_client_destroy.link);
+}
+
+static void drag_set_focus(struct wlr_drag *drag,
+		struct wlr_surface *surface, double sx, double sy) {
+	if (drag->focus == surface) {
+		return;
+	}
+
+	if (drag->focus_client) {
+		wl_list_remove(&drag->seat_client_destroy.link);
+
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
+			wl_data_device_send_leave(resource);
+		}
+
+		drag->focus_client = NULL;
+		drag->focus = NULL;
+	}
+
+	if (!surface || !surface->resource) {
+		return;
+	}
+
+	if (!drag->source &&
+			wl_resource_get_client(surface->resource) !=
+			wl_resource_get_client(drag->seat_client->wl_resource)) {
+		return;
+	}
+
+	if (drag->source && drag->source->offer) {
+		// unlink the offer from the source
+		wl_list_remove(&drag->source->offer->source_destroy.link);
+		drag->source->offer->source = NULL;
+		drag->source->offer = NULL;
+	}
+
+	struct wlr_seat_client *focus_client = wlr_seat_client_for_wl_client(
+		drag->seat_client->seat, wl_resource_get_client(surface->resource));
+	if (!focus_client) {
+		return;
+	}
+
+	struct wl_resource *offer_resource = NULL;
+	if (drag->source) {
+		drag->source->accepted = false;
+		struct wlr_data_offer *offer = data_source_send_offer(drag->source,
+			focus_client);
+		if (offer != NULL) {
+			data_offer_update_action(offer);
+
+			if (wl_resource_get_version(offer->resource) >=
+					WL_DATA_OFFER_SOURCE_ACTIONS_SINCE_VERSION) {
+				wl_data_offer_send_source_actions(offer->resource,
+					drag->source->actions);
+			}
+
+			offer_resource = offer->resource;
+		}
+	}
+
+	if (!wl_list_empty(&focus_client->data_devices)) {
+		uint32_t serial =
+			wl_display_next_serial(drag->seat_client->seat->display);
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &focus_client->data_devices) {
+			wl_data_device_send_enter(resource, serial, surface->resource,
+				wl_fixed_from_double(sx), wl_fixed_from_double(sy),
+				offer_resource);
+		}
+	}
+
+	drag->focus = surface;
+	drag->focus_client = focus_client;
+	drag->seat_client_destroy.notify = drag_handle_seat_client_destroy;
+	wl_signal_add(&focus_client->events.destroy, &drag->seat_client_destroy);
+
+	wlr_signal_emit_safe(&drag->events.focus, drag);
+}
+
+static void drag_end(struct wlr_drag *drag) {
+	if (!drag->cancelling) {
+		drag->cancelling = true;
+		if (drag->is_pointer_grab) {
+			wlr_seat_pointer_end_grab(drag->seat);
+		} else {
+			wlr_seat_touch_end_grab(drag->seat);
+		}
+		wlr_seat_keyboard_end_grab(drag->seat);
+
+		if (drag->source) {
+			wl_list_remove(&drag->source_destroy.link);
+		}
+
+		drag_set_focus(drag, NULL, 0, 0);
+
+		if (drag->icon) {
+			drag->icon->mapped = false;
+			wl_list_remove(&drag->icon_destroy.link);
+			wlr_signal_emit_safe(&drag->icon->events.map, drag->icon);
+		}
+
+		wlr_signal_emit_safe(&drag->events.destroy, drag);
+		free(drag);
+	}
+}
+
+static void drag_handle_pointer_enter(struct wlr_seat_pointer_grab *grab,
+		struct wlr_surface *surface, double sx, double sy) {
+	struct wlr_drag *drag = grab->data;
+	drag_set_focus(drag, surface, sx, sy);
+}
+
+static void drag_handle_pointer_motion(struct wlr_seat_pointer_grab *grab,
+		uint32_t time, double sx, double sy) {
+	struct wlr_drag *drag = grab->data;
+	if (drag->focus != NULL && drag->focus_client != NULL) {
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
+			wl_data_device_send_motion(resource, time, wl_fixed_from_double(sx),
+				wl_fixed_from_double(sy));
+		}
+
+		struct wlr_drag_motion_event event = {
+			.drag = drag,
+			.time = time,
+			.sx = sx,
+			.sy = sy,
+		};
+		wlr_signal_emit_safe(&drag->events.motion, &event);
+	}
+}
+
+static uint32_t drag_handle_pointer_button(struct wlr_seat_pointer_grab *grab,
+		uint32_t time, uint32_t button, uint32_t state) {
+	struct wlr_drag *drag = grab->data;
+
+	if (drag->source &&
+			grab->seat->pointer_state.grab_button == button &&
+			state == WL_POINTER_BUTTON_STATE_RELEASED) {
+		if (drag->focus_client && drag->source->current_dnd_action &&
+				drag->source->accepted) {
+			struct wl_resource *resource;
+			wl_resource_for_each(resource, &drag->focus_client->data_devices) {
+				wl_data_device_send_drop(resource);
+			}
+			wlr_data_source_dnd_drop(drag->source);
+
+			if (drag->source->offer != NULL) {
+				drag->source->offer->in_ask =
+					drag->source->current_dnd_action ==
+					WL_DATA_DEVICE_MANAGER_DND_ACTION_ASK;
+			}
+
+			struct wlr_drag_drop_event event = {
+				.drag = drag,
+				.time = time,
+			};
+			wlr_signal_emit_safe(&drag->events.drop, &event);
+		} else if (drag->source->impl->dnd_finish) {
+			wlr_data_source_cancel(drag->source);
+		}
+	}
+
+	if (grab->seat->pointer_state.button_count == 0 &&
+			state == WL_POINTER_BUTTON_STATE_RELEASED) {
+		drag_end(drag);
+	}
+
+	return 0;
+}
+
+static void drag_handle_pointer_axis(struct wlr_seat_pointer_grab *grab,
+		uint32_t time, enum wlr_axis_orientation orientation, double value) {
+	// This space is intentionally left blank
+}
+
+static void drag_handle_pointer_cancel(struct wlr_seat_pointer_grab *grab) {
+	struct wlr_drag *drag = grab->data;
+	drag_end(drag);
+}
+
+static const struct wlr_pointer_grab_interface
+		data_device_pointer_drag_interface = {
+	.enter = drag_handle_pointer_enter,
+	.motion = drag_handle_pointer_motion,
+	.button = drag_handle_pointer_button,
+	.axis = drag_handle_pointer_axis,
+	.cancel = drag_handle_pointer_cancel,
+};
+
+uint32_t drag_handle_touch_down(struct wlr_seat_touch_grab *grab,
+		uint32_t time, struct wlr_touch_point *point) {
+	// eat the event
+	return 0;
+}
+
+static void drag_handle_touch_up(struct wlr_seat_touch_grab *grab,
+		uint32_t time, struct wlr_touch_point *point) {
+	struct wlr_drag *drag = grab->data;
+	if (drag->grab_touch_id != point->touch_id) {
+		return;
+	}
+
+	if (drag->focus_client) {
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
+			wl_data_device_send_drop(resource);
+		}
+	}
+
+	drag_end(drag);
+}
+
+static void drag_handle_touch_motion(struct wlr_seat_touch_grab *grab,
+		uint32_t time, struct wlr_touch_point *point) {
+	struct wlr_drag *drag = grab->data;
+	if (drag->focus && drag->focus_client) {
+		struct wl_resource *resource;
+		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
+			wl_data_device_send_motion(resource, time,
+				wl_fixed_from_double(point->sx),
+				wl_fixed_from_double(point->sy));
+		}
+	}
+}
+
+static void drag_handle_touch_enter(struct wlr_seat_touch_grab *grab,
+		uint32_t time, struct wlr_touch_point *point) {
+	struct wlr_drag *drag = grab->data;
+	drag_set_focus(drag, point->focus_surface, point->sx, point->sy);
+}
+
+static void drag_handle_touch_cancel(struct wlr_seat_touch_grab *grab) {
+	struct wlr_drag *drag = grab->data;
+	drag_end(drag);
+}
+
+static const struct wlr_touch_grab_interface
+		data_device_touch_drag_interface = {
+	.down = drag_handle_touch_down,
+	.up = drag_handle_touch_up,
+	.motion = drag_handle_touch_motion,
+	.enter = drag_handle_touch_enter,
+	.cancel = drag_handle_touch_cancel,
+};
+
+static void drag_handle_keyboard_enter(struct wlr_seat_keyboard_grab *grab,
+		struct wlr_surface *surface, uint32_t keycodes[], size_t num_keycodes,
+		struct wlr_keyboard_modifiers *modifiers) {
+	// nothing has keyboard focus during drags
+}
+
+static void drag_handle_keyboard_key(struct wlr_seat_keyboard_grab *grab,
+		uint32_t time, uint32_t key, uint32_t state) {
+	// no keyboard input during drags
+}
+
+static void drag_handle_keyboard_modifiers(struct wlr_seat_keyboard_grab *grab,
+		struct wlr_keyboard_modifiers *modifiers) {
+	//struct wlr_keyboard *keyboard = grab->seat->keyboard_state.keyboard;
+	// TODO change the dnd action based on what modifier is pressed on the
+	// keyboard
+}
+
+static void drag_handle_keyboard_cancel(struct wlr_seat_keyboard_grab *grab) {
+	struct wlr_drag *drag = grab->data;
+	drag_end(drag);
+}
+
+static const struct wlr_keyboard_grab_interface
+		data_device_keyboard_drag_interface = {
+	.enter = drag_handle_keyboard_enter,
+	.key = drag_handle_keyboard_key,
+	.modifiers = drag_handle_keyboard_modifiers,
+	.cancel = drag_handle_keyboard_cancel,
+};
+
+static void drag_handle_icon_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_drag *drag = wl_container_of(listener, drag, icon_destroy);
+	drag->icon = NULL;
+}
+
+static void drag_handle_drag_source_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_drag *drag = wl_container_of(listener, drag, source_destroy);
+	drag_end(drag);
+}
+
+
+static void drag_icon_destroy(struct wlr_drag_icon *icon) {
+	if (!icon) {
+		return;
+	}
+	wlr_signal_emit_safe(&icon->events.destroy, icon);
+	wlr_surface_set_role_committed(icon->surface, NULL, NULL);
+	wl_list_remove(&icon->surface_destroy.link);
+	wl_list_remove(&icon->seat_client_destroy.link);
+	wl_list_remove(&icon->link);
+	free(icon);
+}
+
+static void drag_icon_handle_surface_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_drag_icon *icon =
+		wl_container_of(listener, icon, surface_destroy);
+	drag_icon_destroy(icon);
+}
+
+static void drag_icon_handle_surface_commit(struct wlr_surface *surface,
+		void *role_data) {
+	struct wlr_drag_icon *icon = role_data;
+	icon->sx += icon->surface->current->sx;
+	icon->sy += icon->surface->current->sy;
+}
+
+static void drag_icon_handle_seat_client_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_drag_icon *icon =
+		wl_container_of(listener, icon, seat_client_destroy);
+
+	drag_icon_destroy(icon);
+}
+
+static struct wlr_drag_icon *drag_icon_create(
+		struct wlr_surface *icon_surface, struct wlr_seat_client *client,
+		bool is_pointer, int32_t touch_id) {
+	struct wlr_drag_icon *icon = calloc(1, sizeof(struct wlr_drag_icon));
+	if (!icon) {
+		return NULL;
+	}
+
+	icon->surface = icon_surface;
+	icon->client = client;
+	icon->is_pointer = is_pointer;
+	icon->touch_id = touch_id;
+	icon->mapped = true;
+
+	wl_signal_init(&icon->events.map);
+	wl_signal_init(&icon->events.destroy);
+
+	wl_signal_add(&icon->surface->events.destroy, &icon->surface_destroy);
+	icon->surface_destroy.notify = drag_icon_handle_surface_destroy;
+
+	wlr_surface_set_role_committed(icon->surface,
+		drag_icon_handle_surface_commit, icon);
+
+	wl_signal_add(&client->events.destroy, &icon->seat_client_destroy);
+	icon->seat_client_destroy.notify = drag_icon_handle_seat_client_destroy;
+
+	wl_list_insert(&client->seat->drag_icons, &icon->link);
+	wlr_signal_emit_safe(&client->seat->events.new_drag_icon, icon);
+
+	return icon;
+}
+
+
+static void seat_handle_drag_source_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_seat *seat =
+		wl_container_of(listener, seat, drag_source_destroy);
+	wl_list_remove(&seat->drag_source_destroy.link);
+	seat->drag_source = NULL;
+}
+
+bool seat_client_start_drag(struct wlr_seat_client *client,
+		struct wlr_data_source *source, struct wlr_surface *icon_surface,
+		struct wlr_surface *origin, uint32_t serial) {
+	struct wlr_drag *drag = calloc(1, sizeof(struct wlr_drag));
+	if (drag == NULL) {
+		return false;
+	}
+
+	wl_signal_init(&drag->events.focus);
+	wl_signal_init(&drag->events.motion);
+	wl_signal_init(&drag->events.drop);
+	wl_signal_init(&drag->events.destroy);
+
+	struct wlr_seat *seat = client->seat;
+	drag->seat = seat;
+
+	drag->is_pointer_grab = !wl_list_empty(&client->pointers) &&
+		seat->pointer_state.button_count == 1 &&
+		seat->pointer_state.grab_serial == serial &&
+		seat->pointer_state.focused_surface &&
+		seat->pointer_state.focused_surface == origin;
+
+	bool is_touch_grab = !wl_list_empty(&client->touches) &&
+		wlr_seat_touch_num_points(seat) == 1 &&
+		seat->touch_state.grab_serial == serial;
+
+	// set in the iteration
+	struct wlr_touch_point *point = NULL;
+	if (is_touch_grab) {
+		wl_list_for_each(point, &seat->touch_state.touch_points, link) {
+			is_touch_grab = point->surface && point->surface == origin;
+			break;
+		}
+	}
+
+	if (!drag->is_pointer_grab && !is_touch_grab) {
+		free(drag);
+		return true;
+	}
+
+	if (icon_surface) {
+		int32_t touch_id = (point ? point->touch_id : 0);
+		struct wlr_drag_icon *icon =
+			drag_icon_create(icon_surface, client, drag->is_pointer_grab,
+				touch_id);
+		if (!icon) {
+			free(drag);
+			return false;
+		}
+
+		drag->icon = icon;
+		drag->icon_destroy.notify = drag_handle_icon_destroy;
+		wl_signal_add(&icon->events.destroy, &drag->icon_destroy);
+	}
+
+	drag->source = source;
+	if (source != NULL) {
+		drag->source_destroy.notify = drag_handle_drag_source_destroy;
+		wl_signal_add(&source->events.destroy, &drag->source_destroy);
+	}
+
+	drag->seat_client = client;
+	drag->pointer_grab.data = drag;
+	drag->pointer_grab.interface = &data_device_pointer_drag_interface;
+
+	drag->touch_grab.data = drag;
+	drag->touch_grab.interface = &data_device_touch_drag_interface;
+	drag->grab_touch_id = seat->touch_state.grab_id;
+
+	drag->keyboard_grab.data = drag;
+	drag->keyboard_grab.interface = &data_device_keyboard_drag_interface;
+
+	wlr_seat_keyboard_start_grab(seat, &drag->keyboard_grab);
+
+	if (drag->is_pointer_grab) {
+		wlr_seat_pointer_clear_focus(seat);
+		wlr_seat_pointer_start_grab(seat, &drag->pointer_grab);
+	} else {
+		assert(point);
+		wlr_seat_touch_start_grab(seat, &drag->touch_grab);
+		drag_set_focus(drag, point->surface, point->sx, point->sy);
+	}
+
+	seat->drag = drag; // TODO: unset this thing somewhere
+	seat->drag_serial = serial;
+
+	seat->drag_source = source;
+	if (source != NULL) {
+		seat->drag_source_destroy.notify = seat_handle_drag_source_destroy;
+		wl_signal_add(&source->events.destroy, &seat->drag_source_destroy);
+	}
+
+	wlr_signal_emit_safe(&seat->events.start_drag, drag);
+
+	return true;
+}
diff --git a/types/meson.build b/types/meson.build
index 7e089d03..f06bba30 100644
--- a/types/meson.build
+++ b/types/meson.build
@@ -1,10 +1,13 @@
 lib_wlr_types = static_library(
 	'wlr_types',
 	files(
+		'data_device/wlr_data_device.c',
+		'data_device/wlr_data_offer.c',
+		'data_device/wlr_data_source.c',
+		'data_device/wlr_drag.c',
 		'wlr_box.c',
 		'wlr_compositor.c',
 		'wlr_cursor.c',
-		'wlr_data_device.c',
 		'wlr_gamma_control.c',
 		'wlr_idle_inhibit_v1.c',
 		'wlr_idle.c',
diff --git a/types/wlr_data_device.c b/types/wlr_data_device.c
deleted file mode 100644
index 23e54809..00000000
--- a/types/wlr_data_device.c
+++ /dev/null
@@ -1,1203 +0,0 @@
-#define _XOPEN_SOURCE 700
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-#include <strings.h>
-#include <unistd.h>
-#include <wayland-server.h>
-#include <wlr/types/wlr_data_device.h>
-#include <wlr/types/wlr_seat.h>
-#include <wlr/util/log.h>
-#include "util/signal.h"
-
-#define ALL_ACTIONS (WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY | \
-		WL_DATA_DEVICE_MANAGER_DND_ACTION_MOVE | \
-		WL_DATA_DEVICE_MANAGER_DND_ACTION_ASK)
-
-static const struct wl_data_offer_interface data_offer_impl;
-
-static struct wlr_data_offer *data_offer_from_resource(
-		struct wl_resource *resource) {
-	assert(wl_resource_instance_of(resource, &wl_data_offer_interface,
-		&data_offer_impl));
-	return wl_resource_get_user_data(resource);
-}
-
-static const struct wl_data_source_interface data_source_impl;
-
-static struct client_data_source *client_data_source_from_resource(
-		struct wl_resource *resource) {
-	assert(wl_resource_instance_of(resource, &wl_data_source_interface,
-		&data_source_impl));
-	return wl_resource_get_user_data(resource);
-}
-
-static uint32_t data_offer_choose_action(struct wlr_data_offer *offer) {
-	uint32_t offer_actions, preferred_action = 0;
-	if (wl_resource_get_version(offer->resource) >=
-			WL_DATA_OFFER_ACTION_SINCE_VERSION) {
-		offer_actions = offer->actions;
-		preferred_action = offer->preferred_action;
-	} else {
-		offer_actions = WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY;
-	}
-
-	uint32_t source_actions;
-	if (offer->source->actions >= 0) {
-		source_actions = offer->source->actions;
-	} else {
-		source_actions = WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY;
-	}
-
-	uint32_t available_actions = offer_actions & source_actions;
-	if (!available_actions) {
-		return WL_DATA_DEVICE_MANAGER_DND_ACTION_NONE;
-	}
-
-	if (offer->source->seat_client &&
-			offer->source->compositor_action & available_actions) {
-		return offer->source->compositor_action;
-	}
-
-	// If the dest side has a preferred DnD action, use it
-	if ((preferred_action & available_actions) != 0) {
-		return preferred_action;
-	}
-
-	// Use the first found action, in bit order
-	return 1 << (ffs(available_actions) - 1);
-}
-
-static void data_offer_update_action(struct wlr_data_offer *offer) {
-	if (!offer->source) {
-		return;
-	}
-
-	uint32_t action = data_offer_choose_action(offer);
-	if (offer->source->current_dnd_action == action) {
-		return;
-	}
-
-	offer->source->current_dnd_action = action;
-
-	if (offer->in_ask) {
-		return;
-	}
-
-	wlr_data_source_dnd_action(offer->source, action);
-
-	if (wl_resource_get_version(offer->resource) >=
-			WL_DATA_OFFER_ACTION_SINCE_VERSION) {
-		wl_data_offer_send_action(offer->resource, action);
-	}
-}
-
-static void data_offer_accept(struct wl_client *client,
-		struct wl_resource *resource, uint32_t serial, const char *mime_type) {
-	struct wlr_data_offer *offer = data_offer_from_resource(resource);
-
-	if (!offer->source || offer != offer->source->offer) {
-		return;
-	}
-
-	// TODO check that client is currently focused by the input device
-
-	wlr_data_source_accept(offer->source, serial, mime_type);
-}
-
-static void data_offer_receive(struct wl_client *client,
-		struct wl_resource *resource, const char *mime_type, int32_t fd) {
-	struct wlr_data_offer *offer = data_offer_from_resource(resource);
-
-	if (offer->source && offer == offer->source->offer) {
-		wlr_data_source_send(offer->source, mime_type, fd);
-	} else {
-		close(fd);
-	}
-}
-static void data_offer_destroy(struct wl_client *client,
-		struct wl_resource *resource) {
-	wl_resource_destroy(resource);
-}
-
-static void data_source_notify_finish(struct wlr_data_source *source) {
-	assert(source->offer);
-	if (source->actions < 0) {
-		return;
-	}
-
-	if (source->offer->in_ask) {
-		wlr_data_source_dnd_action(source, source->current_dnd_action);
-	}
-
-	source->offer = NULL;
-	wlr_data_source_dnd_finish(source);
-}
-
-static void data_offer_finish(struct wl_client *client,
-		struct wl_resource *resource) {
-	struct wlr_data_offer *offer = data_offer_from_resource(resource);
-
-	if (!offer->source || offer->source->offer != offer) {
-		return;
-	}
-
-	data_source_notify_finish(offer->source);
-}
-
-static void data_offer_set_actions(struct wl_client *client,
-		struct wl_resource *resource, uint32_t actions,
-		uint32_t preferred_action) {
-	struct wlr_data_offer *offer = data_offer_from_resource(resource);
-
-	if (actions & ~ALL_ACTIONS) {
-		wl_resource_post_error(offer->resource,
-			WL_DATA_OFFER_ERROR_INVALID_ACTION_MASK,
-			"invalid action mask %x", actions);
-		return;
-	}
-
-	if (preferred_action && (!(preferred_action & actions) ||
-			__builtin_popcount(preferred_action) > 1)) {
-		wl_resource_post_error(offer->resource,
-			WL_DATA_OFFER_ERROR_INVALID_ACTION,
-			"invalid action %x", preferred_action);
-		return;
-	}
-
-	offer->actions = actions;
-	offer->preferred_action = preferred_action;
-
-	data_offer_update_action(offer);
-}
-
-static void data_offer_resource_destroy(struct wl_resource *resource) {
-	struct wlr_data_offer *offer = data_offer_from_resource(resource);
-
-	if (!offer->source) {
-		goto out;
-	}
-
-	wl_list_remove(&offer->source_destroy.link);
-
-	if (offer->source->offer != offer) {
-		goto out;
-	}
-
-	// If the drag destination has version < 3, wl_data_offer.finish
-	// won't be called, so do this here as a safety net, because
-	// we still want the version >= 3 drag source to be happy.
-	if (wl_resource_get_version(offer->resource) <
-			WL_DATA_OFFER_ACTION_SINCE_VERSION) {
-		data_source_notify_finish(offer->source);
-		offer->source->offer = NULL;
-	} else if (offer->source->impl->dnd_finish) {
-		// source->cancel can free the source
-		offer->source->offer = NULL;
-		wlr_data_source_cancel(offer->source);
-	} else {
-		offer->source->offer = NULL;
-	}
-
-out:
-	free(offer);
-}
-
-static const struct wl_data_offer_interface data_offer_impl = {
-	.accept = data_offer_accept,
-	.receive = data_offer_receive,
-	.destroy = data_offer_destroy,
-	.finish = data_offer_finish,
-	.set_actions = data_offer_set_actions,
-};
-
-static void handle_offer_source_destroyed(struct wl_listener *listener,
-		void *data) {
-	struct wlr_data_offer *offer =
-		wl_container_of(listener, offer, source_destroy);
-
-	offer->source = NULL;
-}
-
-static struct wlr_data_offer *data_source_send_offer(
-		struct wlr_data_source *source,
-		struct wlr_seat_client *target) {
-	if (wl_list_empty(&target->data_devices)) {
-		return NULL;
-	}
-
-	struct wlr_data_offer *offer = calloc(1, sizeof(struct wlr_data_offer));
-	if (offer == NULL) {
-		return NULL;
-	}
-
-	uint32_t version = wl_resource_get_version(
-		wl_resource_from_link(target->data_devices.next));
-	offer->resource = wl_resource_create(target->client,
-		&wl_data_offer_interface, version, 0);
-	if (offer->resource == NULL) {
-		free(offer);
-		return NULL;
-	}
-	wl_resource_set_implementation(offer->resource, &data_offer_impl, offer,
-		data_offer_resource_destroy);
-
-	offer->source_destroy.notify = handle_offer_source_destroyed;
-	wl_signal_add(&source->events.destroy, &offer->source_destroy);
-
-	struct wl_resource *target_resource;
-	wl_resource_for_each(target_resource, &target->data_devices) {
-		wl_data_device_send_data_offer(target_resource, offer->resource);
-	}
-
-	char **p;
-	wl_array_for_each(p, &source->mime_types) {
-		wl_data_offer_send_offer(offer->resource, *p);
-	}
-
-	offer->source = source;
-	source->offer = offer;
-	source->accepted = false;
-
-	return offer;
-}
-
-void wlr_seat_client_send_selection(struct wlr_seat_client *seat_client) {
-	if (wl_list_empty(&seat_client->data_devices)) {
-		return;
-	}
-
-	if (seat_client->seat->selection_source) {
-		struct wlr_data_offer *offer = data_source_send_offer(
-			seat_client->seat->selection_source, seat_client);
-		if (offer == NULL) {
-			return;
-		}
-
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &seat_client->data_devices) {
-			wl_data_device_send_selection(resource, offer->resource);
-		}
-	} else {
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &seat_client->data_devices) {
-			wl_data_device_send_selection(resource, NULL);
-		}
-	}
-}
-
-static void seat_client_selection_source_destroy(
-		struct wl_listener *listener, void *data) {
-	struct wlr_seat *seat =
-		wl_container_of(listener, seat, selection_source_destroy);
-	struct wlr_seat_client *seat_client = seat->keyboard_state.focused_client;
-
-	if (seat_client && seat->keyboard_state.focused_surface) {
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &seat_client->data_devices) {
-			wl_data_device_send_selection(resource, NULL);
-		}
-	}
-
-	seat->selection_source = NULL;
-
-	wlr_signal_emit_safe(&seat->events.selection, seat);
-}
-
-void wlr_seat_set_selection(struct wlr_seat *seat,
-		struct wlr_data_source *source, uint32_t serial) {
-	if (seat->selection_source &&
-			seat->selection_serial - serial < UINT32_MAX / 2) {
-		return;
-	}
-
-	if (seat->selection_source) {
-		wl_list_remove(&seat->selection_source_destroy.link);
-		wlr_data_source_cancel(seat->selection_source);
-		seat->selection_source = NULL;
-	}
-
-	seat->selection_source = source;
-	seat->selection_serial = serial;
-
-	struct wlr_seat_client *focused_client =
-		seat->keyboard_state.focused_client;
-
-	if (focused_client) {
-		wlr_seat_client_send_selection(focused_client);
-	}
-
-	wlr_signal_emit_safe(&seat->events.selection, seat);
-
-	if (source) {
-		seat->selection_source_destroy.notify =
-			seat_client_selection_source_destroy;
-		wl_signal_add(&source->events.destroy,
-			&seat->selection_source_destroy);
-	}
-}
-
-static const struct wl_data_device_interface data_device_impl;
-
-static struct wlr_seat_client *seat_client_from_data_device_resource(
-		struct wl_resource *resource) {
-	assert(wl_resource_instance_of(resource, &wl_data_device_interface,
-		&data_device_impl));
-	return wl_resource_get_user_data(resource);
-}
-
-static void data_device_set_selection(struct wl_client *client,
-		struct wl_resource *device_resource,
-		struct wl_resource *source_resource, uint32_t serial) {
-	struct client_data_source *source = NULL;
-	if (source_resource != NULL) {
-		source = client_data_source_from_resource(source_resource);
-	}
-
-	struct wlr_seat_client *seat_client =
-		seat_client_from_data_device_resource(device_resource);
-
-	struct wlr_data_source *wlr_source = (struct wlr_data_source *)source;
-	wlr_seat_set_selection(seat_client->seat, wlr_source, serial);
-}
-
-static void data_device_release(struct wl_client *client,
-		struct wl_resource *resource) {
-	wl_resource_destroy(resource);
-}
-
-static void handle_drag_seat_client_destroy(struct wl_listener *listener,
-		void *data) {
-	struct wlr_drag *drag =
-		wl_container_of(listener, drag, seat_client_destroy);
-
-	drag->focus_client = NULL;
-	wl_list_remove(&drag->seat_client_destroy.link);
-}
-
-static void drag_set_focus(struct wlr_drag *drag,
-		struct wlr_surface *surface, double sx, double sy) {
-	if (drag->focus == surface) {
-		return;
-	}
-
-	if (drag->focus_client) {
-		wl_list_remove(&drag->seat_client_destroy.link);
-
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
-			wl_data_device_send_leave(resource);
-		}
-
-		drag->focus_client = NULL;
-		drag->focus = NULL;
-	}
-
-	if (!surface || !surface->resource) {
-		return;
-	}
-
-	if (!drag->source &&
-			wl_resource_get_client(surface->resource) !=
-			wl_resource_get_client(drag->seat_client->wl_resource)) {
-		return;
-	}
-
-	if (drag->source && drag->source->offer) {
-		// unlink the offer from the source
-		wl_list_remove(&drag->source->offer->source_destroy.link);
-		drag->source->offer->source = NULL;
-		drag->source->offer = NULL;
-	}
-
-	struct wlr_seat_client *focus_client =
-		wlr_seat_client_for_wl_client(drag->seat_client->seat,
-			wl_resource_get_client(surface->resource));
-	if (!focus_client) {
-		return;
-	}
-
-	struct wl_resource *offer_resource = NULL;
-	if (drag->source) {
-		drag->source->accepted = false;
-		struct wlr_data_offer *offer = data_source_send_offer(drag->source,
-			focus_client);
-		if (offer != NULL) {
-			data_offer_update_action(offer);
-
-			if (wl_resource_get_version(offer->resource) >=
-					WL_DATA_OFFER_SOURCE_ACTIONS_SINCE_VERSION) {
-				wl_data_offer_send_source_actions(offer->resource,
-					drag->source->actions);
-			}
-
-			offer_resource = offer->resource;
-		}
-	}
-
-	if (!wl_list_empty(&focus_client->data_devices)) {
-		uint32_t serial =
-			wl_display_next_serial(drag->seat_client->seat->display);
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &focus_client->data_devices) {
-			wl_data_device_send_enter(resource, serial, surface->resource,
-				wl_fixed_from_double(sx), wl_fixed_from_double(sy),
-				offer_resource);
-		}
-	}
-
-	drag->focus = surface;
-	drag->focus_client = focus_client;
-	drag->seat_client_destroy.notify = handle_drag_seat_client_destroy;
-	wl_signal_add(&focus_client->events.destroy, &drag->seat_client_destroy);
-
-	wlr_signal_emit_safe(&drag->events.focus, drag);
-}
-
-static void drag_end(struct wlr_drag *drag) {
-	if (!drag->cancelling) {
-		drag->cancelling = true;
-		if (drag->is_pointer_grab) {
-			wlr_seat_pointer_end_grab(drag->seat);
-		} else {
-			wlr_seat_touch_end_grab(drag->seat);
-		}
-		wlr_seat_keyboard_end_grab(drag->seat);
-
-		if (drag->source) {
-			wl_list_remove(&drag->source_destroy.link);
-		}
-
-		drag_set_focus(drag, NULL, 0, 0);
-
-		if (drag->icon) {
-			drag->icon->mapped = false;
-			wl_list_remove(&drag->icon_destroy.link);
-			wlr_signal_emit_safe(&drag->icon->events.map, drag->icon);
-		}
-
-		wlr_signal_emit_safe(&drag->events.destroy, drag);
-		free(drag);
-	}
-}
-
-static void pointer_drag_enter(struct wlr_seat_pointer_grab *grab,
-		struct wlr_surface *surface, double sx, double sy) {
-	struct wlr_drag *drag = grab->data;
-	drag_set_focus(drag, surface, sx, sy);
-}
-
-static void pointer_drag_motion(struct wlr_seat_pointer_grab *grab,
-		uint32_t time, double sx, double sy) {
-	struct wlr_drag *drag = grab->data;
-	if (drag->focus != NULL && drag->focus_client != NULL) {
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
-			wl_data_device_send_motion(resource, time, wl_fixed_from_double(sx),
-				wl_fixed_from_double(sy));
-		}
-
-		struct wlr_drag_motion_event event = {
-			.drag = drag,
-			.time = time,
-			.sx = sx,
-			.sy = sy,
-		};
-		wlr_signal_emit_safe(&drag->events.motion, &event);
-	}
-}
-
-static uint32_t pointer_drag_button(struct wlr_seat_pointer_grab *grab,
-		uint32_t time, uint32_t button, uint32_t state) {
-	struct wlr_drag *drag = grab->data;
-
-	if (drag->source &&
-			grab->seat->pointer_state.grab_button == button &&
-			state == WL_POINTER_BUTTON_STATE_RELEASED) {
-		if (drag->focus_client && drag->source->current_dnd_action &&
-				drag->source->accepted) {
-			struct wl_resource *resource;
-			wl_resource_for_each(resource, &drag->focus_client->data_devices) {
-				wl_data_device_send_drop(resource);
-			}
-			wlr_data_source_dnd_drop(drag->source);
-
-			if (drag->source->offer != NULL) {
-				drag->source->offer->in_ask =
-					drag->source->current_dnd_action ==
-					WL_DATA_DEVICE_MANAGER_DND_ACTION_ASK;
-			}
-
-			struct wlr_drag_drop_event event = {
-				.drag = drag,
-				.time = time,
-			};
-			wlr_signal_emit_safe(&drag->events.drop, &event);
-		} else if (drag->source->impl->dnd_finish) {
-			wlr_data_source_cancel(drag->source);
-		}
-	}
-
-	if (grab->seat->pointer_state.button_count == 0 &&
-			state == WL_POINTER_BUTTON_STATE_RELEASED) {
-		drag_end(drag);
-	}
-
-	return 0;
-}
-
-static void pointer_drag_axis(struct wlr_seat_pointer_grab *grab, uint32_t time,
-		enum wlr_axis_orientation orientation, double value) {
-	// This space is intentionally left blank
-}
-
-static void pointer_drag_cancel(struct wlr_seat_pointer_grab *grab) {
-	struct wlr_drag *drag = grab->data;
-	drag_end(drag);
-}
-
-static const struct wlr_pointer_grab_interface
-		data_device_pointer_drag_interface = {
-	.enter = pointer_drag_enter,
-	.motion = pointer_drag_motion,
-	.button = pointer_drag_button,
-	.axis = pointer_drag_axis,
-	.cancel = pointer_drag_cancel,
-};
-
-uint32_t touch_drag_down(struct wlr_seat_touch_grab *grab,
-		uint32_t time, struct wlr_touch_point *point) {
-	// eat the event
-	return 0;
-}
-
-static void touch_drag_up(struct wlr_seat_touch_grab *grab, uint32_t time,
-		struct wlr_touch_point *point) {
-	struct wlr_drag *drag = grab->data;
-	if (drag->grab_touch_id != point->touch_id) {
-		return;
-	}
-
-	if (drag->focus_client) {
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
-			wl_data_device_send_drop(resource);
-		}
-	}
-
-	drag_end(drag);
-}
-
-static void touch_drag_motion(struct wlr_seat_touch_grab *grab, uint32_t time,
-		struct wlr_touch_point *point) {
-	struct wlr_drag *drag = grab->data;
-	if (drag->focus && drag->focus_client) {
-		struct wl_resource *resource;
-		wl_resource_for_each(resource, &drag->focus_client->data_devices) {
-			wl_data_device_send_motion(resource, time,
-				wl_fixed_from_double(point->sx),
-				wl_fixed_from_double(point->sy));
-		}
-	}
-}
-
-static void touch_drag_enter(struct wlr_seat_touch_grab *grab, uint32_t time,
-		struct wlr_touch_point *point) {
-	struct wlr_drag *drag = grab->data;
-	drag_set_focus(drag, point->focus_surface, point->sx, point->sy);
-}
-
-static void touch_drag_cancel(struct wlr_seat_touch_grab *grab) {
-	struct wlr_drag *drag = grab->data;
-	drag_end(drag);
-}
-
-static const struct wlr_touch_grab_interface
-		data_device_touch_drag_interface = {
-	.down = touch_drag_down,
-	.up = touch_drag_up,
-	.motion = touch_drag_motion,
-	.enter = touch_drag_enter,
-	.cancel = touch_drag_cancel,
-};
-
-static void keyboard_drag_enter(struct wlr_seat_keyboard_grab *grab,
-		struct wlr_surface *surface, uint32_t keycodes[], size_t num_keycodes,
-		struct wlr_keyboard_modifiers *modifiers) {
-	// nothing has keyboard focus during drags
-}
-
-static void keyboard_drag_key(struct wlr_seat_keyboard_grab *grab,
-		uint32_t time, uint32_t key, uint32_t state) {
-	// no keyboard input during drags
-}
-
-static void keyboard_drag_modifiers(struct wlr_seat_keyboard_grab *grab,
-		struct wlr_keyboard_modifiers *modifiers) {
-	//struct wlr_keyboard *keyboard = grab->seat->keyboard_state.keyboard;
-	// TODO change the dnd action based on what modifier is pressed on the
-	// keyboard
-}
-
-static void keyboard_drag_cancel(struct wlr_seat_keyboard_grab *grab) {
-	struct wlr_drag *drag = grab->data;
-	drag_end(drag);
-}
-
-static const struct wlr_keyboard_grab_interface
-		data_device_keyboard_drag_interface = {
-	.enter = keyboard_drag_enter,
-	.key = keyboard_drag_key,
-	.modifiers = keyboard_drag_modifiers,
-	.cancel = keyboard_drag_cancel,
-};
-
-static void drag_handle_icon_destroy(struct wl_listener *listener, void *data) {
-	struct wlr_drag *drag = wl_container_of(listener, drag, icon_destroy);
-	drag->icon = NULL;
-}
-
-static void drag_handle_drag_source_destroy(struct wl_listener *listener,
-		void *data) {
-	struct wlr_drag *drag = wl_container_of(listener, drag, source_destroy);
-	drag_end(drag);
-}
-
-static void drag_icon_destroy(struct wlr_drag_icon *icon) {
-	if (!icon) {
-		return;
-	}
-	wlr_signal_emit_safe(&icon->events.destroy, icon);
-	wlr_surface_set_role_committed(icon->surface, NULL, NULL);
-	wl_list_remove(&icon->surface_destroy.link);
-	wl_list_remove(&icon->seat_client_destroy.link);
-	wl_list_remove(&icon->link);
-	free(icon);
-}
-
-static void handle_drag_icon_surface_destroy(struct wl_listener *listener,
-		void *data) {
-	struct wlr_drag_icon *icon =
-		wl_container_of(listener, icon, surface_destroy);
-	drag_icon_destroy(icon);
-}
-
-static void handle_drag_icon_surface_commit(struct wlr_surface *surface,
-		void *role_data) {
-	struct wlr_drag_icon *icon = role_data;
-	icon->sx += icon->surface->current->sx;
-	icon->sy += icon->surface->current->sy;
-}
-
-static void handle_drag_icon_seat_client_destroy(struct wl_listener *listener,
-		void *data) {
-	struct wlr_drag_icon *icon =
-		wl_container_of(listener, icon, seat_client_destroy);
-
-	drag_icon_destroy(icon);
-}
-
-static struct wlr_drag_icon *drag_icon_create(
-		struct wlr_surface *icon_surface, struct wlr_seat_client *client,
-		bool is_pointer, int32_t touch_id) {
-	struct wlr_drag_icon *icon = calloc(1, sizeof(struct wlr_drag_icon));
-	if (!icon) {
-		return NULL;
-	}
-
-	icon->surface = icon_surface;
-	icon->client = client;
-	icon->is_pointer = is_pointer;
-	icon->touch_id = touch_id;
-	icon->mapped = true;
-
-	wl_signal_init(&icon->events.map);
-	wl_signal_init(&icon->events.destroy);
-
-	wl_signal_add(&icon->surface->events.destroy, &icon->surface_destroy);
-	icon->surface_destroy.notify = handle_drag_icon_surface_destroy;
-
-	wlr_surface_set_role_committed(icon->surface,
-		handle_drag_icon_surface_commit, icon);
-
-	wl_signal_add(&client->events.destroy, &icon->seat_client_destroy);
-	icon->seat_client_destroy.notify = handle_drag_icon_seat_client_destroy;
-
-	wl_list_insert(&client->seat->drag_icons, &icon->link);
-	wlr_signal_emit_safe(&client->seat->events.new_drag_icon, icon);
-
-	return icon;
-}
-
-static void seat_handle_drag_source_destroy(struct wl_listener *listener,
-		void *data) {
-	struct wlr_seat *seat =
-		wl_container_of(listener, seat, drag_source_destroy);
-	wl_list_remove(&seat->drag_source_destroy.link);
-	seat->drag_source = NULL;
-}
-
-static bool seat_client_start_drag(struct wlr_seat_client *client,
-		struct wlr_data_source *source, struct wlr_surface *icon_surface,
-		struct wlr_surface *origin, uint32_t serial) {
-	struct wlr_drag *drag = calloc(1, sizeof(struct wlr_drag));
-	if (drag == NULL) {
-		return false;
-	}
-
-	wl_signal_init(&drag->events.focus);
-	wl_signal_init(&drag->events.motion);
-	wl_signal_init(&drag->events.drop);
-	wl_signal_init(&drag->events.destroy);
-
-	struct wlr_seat *seat = client->seat;
-	drag->seat = seat;
-
-	drag->is_pointer_grab = !wl_list_empty(&client->pointers) &&
-		seat->pointer_state.button_count == 1 &&
-		seat->pointer_state.grab_serial == serial &&
-		seat->pointer_state.focused_surface &&
-		seat->pointer_state.focused_surface == origin;
-
-	bool is_touch_grab = !wl_list_empty(&client->touches) &&
-		wlr_seat_touch_num_points(seat) == 1 &&
-		seat->touch_state.grab_serial == serial;
-
-	// set in the iteration
-	struct wlr_touch_point *point = NULL;
-	if (is_touch_grab) {
-		wl_list_for_each(point, &seat->touch_state.touch_points, link) {
-			is_touch_grab = point->surface && point->surface == origin;
-			break;
-		}
-	}
-
-	if (!drag->is_pointer_grab && !is_touch_grab) {
-		free(drag);
-		return true;
-	}
-
-	if (icon_surface) {
-		int32_t touch_id = (point ? point->touch_id : 0);
-		struct wlr_drag_icon *icon =
-			drag_icon_create(icon_surface, client, drag->is_pointer_grab,
-				touch_id);
-		if (!icon) {
-			free(drag);
-			return false;
-		}
-
-		drag->icon = icon;
-		drag->icon_destroy.notify = drag_handle_icon_destroy;
-		wl_signal_add(&icon->events.destroy, &drag->icon_destroy);
-	}
-
-	drag->source = source;
-	if (source != NULL) {
-		drag->source_destroy.notify = drag_handle_drag_source_destroy;
-		wl_signal_add(&source->events.destroy, &drag->source_destroy);
-	}
-
-	drag->seat_client = client;
-	drag->pointer_grab.data = drag;
-	drag->pointer_grab.interface = &data_device_pointer_drag_interface;
-
-	drag->touch_grab.data = drag;
-	drag->touch_grab.interface = &data_device_touch_drag_interface;
-	drag->grab_touch_id = seat->touch_state.grab_id;
-
-	drag->keyboard_grab.data = drag;
-	drag->keyboard_grab.interface = &data_device_keyboard_drag_interface;
-
-	wlr_seat_keyboard_start_grab(seat, &drag->keyboard_grab);
-
-	if (drag->is_pointer_grab) {
-		wlr_seat_pointer_clear_focus(seat);
-		wlr_seat_pointer_start_grab(seat, &drag->pointer_grab);
-	} else {
-		assert(point);
-		wlr_seat_touch_start_grab(seat, &drag->touch_grab);
-		drag_set_focus(drag, point->surface, point->sx, point->sy);
-	}
-
-	seat->drag = drag; // TODO: unset this thing somewhere
-	seat->drag_serial = serial;
-
-	seat->drag_source = source;
-	if (source != NULL) {
-		seat->drag_source_destroy.notify = seat_handle_drag_source_destroy;
-		wl_signal_add(&source->events.destroy, &seat->drag_source_destroy);
-	}
-
-	wlr_signal_emit_safe(&seat->events.start_drag, drag);
-
-	return true;
-}
-
-static void data_device_start_drag(struct wl_client *client,
-		struct wl_resource *device_resource,
-		struct wl_resource *source_resource,
-		struct wl_resource *origin_resource, struct wl_resource *icon_resource,
-		uint32_t serial) {
-	struct wlr_seat_client *seat_client =
-		seat_client_from_data_device_resource(device_resource);
-	struct wlr_surface *origin = wlr_surface_from_resource(origin_resource);
-	struct wlr_data_source *source = NULL;
-	struct wlr_surface *icon = NULL;
-
-	if (source_resource) {
-		struct client_data_source *client_source =
-			client_data_source_from_resource(source_resource);
-		source = (struct wlr_data_source *)client_source;
-	}
-
-	if (icon_resource) {
-		icon = wlr_surface_from_resource(icon_resource);
-	}
-	if (icon) {
-		if (wlr_surface_set_role(icon, "wl_data_device-icon",
-					icon_resource, WL_DATA_DEVICE_ERROR_ROLE) < 0) {
-			return;
-		}
-	}
-
-	if (!seat_client_start_drag(seat_client, source, icon, origin, serial)) {
-		wl_resource_post_no_memory(device_resource);
-		return;
-	}
-
-	if (source) {
-		source->seat_client = seat_client;
-	}
-}
-
-static const struct wl_data_device_interface data_device_impl = {
-	.start_drag = data_device_start_drag,
-	.set_selection = data_device_set_selection,
-	.release = data_device_release,
-};
-
-static void data_device_destroy(struct wl_resource *resource) {
-	wl_list_remove(wl_resource_get_link(resource));
-}
-
-
-struct client_data_source {
-	struct wlr_data_source source;
-	struct wlr_data_source_impl impl;
-	struct wl_resource *resource;
-};
-
-static void client_data_source_accept(struct wlr_data_source *wlr_source,
-	uint32_t serial, const char *mime_type);
-
-static struct client_data_source *client_data_source_from_wlr_data_source(
-		struct wlr_data_source *wlr_source) {
-	assert(wlr_source->impl->accept == client_data_source_accept);
-	return (struct client_data_source *)wlr_source;
-}
-
-static void client_data_source_accept(struct wlr_data_source *wlr_source,
-		uint32_t serial, const char *mime_type) {
-	struct client_data_source *source =
-		client_data_source_from_wlr_data_source(wlr_source);
-	wl_data_source_send_target(source->resource, mime_type);
-}
-
-static void client_data_source_send(struct wlr_data_source *wlr_source,
-		const char *mime_type, int32_t fd) {
-	struct client_data_source *source =
-		client_data_source_from_wlr_data_source(wlr_source);
-	wl_data_source_send_send(source->resource, mime_type, fd);
-	close(fd);
-}
-
-static void client_data_source_cancel(struct wlr_data_source *wlr_source) {
-	struct client_data_source *source =
-		client_data_source_from_wlr_data_source(wlr_source);
-	wl_data_source_send_cancelled(source->resource);
-}
-
-static void client_data_source_dnd_drop(struct wlr_data_source *wlr_source) {
-	struct client_data_source *source =
-		client_data_source_from_wlr_data_source(wlr_source);
-	assert(wl_resource_get_version(source->resource) >=
-		WL_DATA_SOURCE_DND_DROP_PERFORMED_SINCE_VERSION);
-	wl_data_source_send_dnd_drop_performed(source->resource);
-}
-
-static void client_data_source_dnd_finish(struct wlr_data_source *wlr_source) {
-	struct client_data_source *source =
-		client_data_source_from_wlr_data_source(wlr_source);
-	assert(wl_resource_get_version(source->resource) >=
-		WL_DATA_SOURCE_DND_FINISHED_SINCE_VERSION);
-	wl_data_source_send_dnd_finished(source->resource);
-}
-
-static void client_data_source_dnd_action(struct wlr_data_source *wlr_source,
-		enum wl_data_device_manager_dnd_action action) {
-	struct client_data_source *source =
-		client_data_source_from_wlr_data_source(wlr_source);
-	assert(wl_resource_get_version(source->resource) >=
-		WL_DATA_SOURCE_ACTION_SINCE_VERSION);
-	wl_data_source_send_action(source->resource, action);
-}
-
-static void data_source_destroy(struct wl_client *client,
-		struct wl_resource *resource) {
-	wl_resource_destroy(resource);
-}
-
-static struct client_data_source *client_data_source_create(
-		struct wl_resource *source_resource) {
-	struct client_data_source *source =
-		calloc(1, sizeof(struct client_data_source));
-	if (source == NULL) {
-		return NULL;
-	}
-
-	source->resource = source_resource;
-
-	source->impl.accept = client_data_source_accept;
-	source->impl.send = client_data_source_send;
-	source->impl.cancel = client_data_source_cancel;
-
-	if (wl_resource_get_version(source->resource) >=
-			WL_DATA_SOURCE_DND_DROP_PERFORMED_SINCE_VERSION) {
-		source->impl.dnd_drop = client_data_source_dnd_drop;
-	}
-	if (wl_resource_get_version(source->resource) >=
-			WL_DATA_SOURCE_DND_FINISHED_SINCE_VERSION) {
-		source->impl.dnd_finish = client_data_source_dnd_finish;
-	}
-	if (wl_resource_get_version(source->resource) >=
-			WL_DATA_SOURCE_ACTION_SINCE_VERSION) {
-		source->impl.dnd_action = client_data_source_dnd_action;
-	}
-
-	wlr_data_source_init(&source->source, &source->impl);
-	return source;
-}
-
-static void data_source_set_actions(struct wl_client *client,
-		struct wl_resource *resource, uint32_t dnd_actions) {
-	struct client_data_source *source =
-		client_data_source_from_resource(resource);
-
-	if (source->source.actions >= 0) {
-		wl_resource_post_error(source->resource,
-			WL_DATA_SOURCE_ERROR_INVALID_ACTION_MASK,
-			"cannot set actions more than once");
-		return;
-	}
-
-	if (dnd_actions & ~ALL_ACTIONS) {
-		wl_resource_post_error(source->resource,
-			WL_DATA_SOURCE_ERROR_INVALID_ACTION_MASK,
-			"invalid action mask %x", dnd_actions);
-		return;
-	}
-
-	if (source->source.seat_client) {
-		wl_resource_post_error(source->resource,
-			WL_DATA_SOURCE_ERROR_INVALID_ACTION_MASK,
-			"invalid action change after "
-			"wl_data_device.start_drag");
-		return;
-	}
-
-	source->source.actions = dnd_actions;
-}
-
-static void data_source_offer(struct wl_client *client,
-		struct wl_resource *resource, const char *mime_type) {
-	struct client_data_source *source =
-		client_data_source_from_resource(resource);
-
-	char **p = wl_array_add(&source->source.mime_types, sizeof(*p));
-	if (p) {
-		*p = strdup(mime_type);
-	}
-	if (!p || !*p) {
-		if (p) {
-			source->source.mime_types.size -= sizeof(*p);
-		}
-		wl_resource_post_no_memory(resource);
-	}
-}
-
-static const struct wl_data_source_interface data_source_impl = {
-	.offer = data_source_offer,
-	.destroy = data_source_destroy,
-	.set_actions = data_source_set_actions,
-};
-
-static void data_source_resource_handle_destroy(struct wl_resource *resource) {
-	struct client_data_source *source =
-		client_data_source_from_resource(resource);
-	wlr_data_source_finish(&source->source);
-	free(source);
-}
-
-void wlr_data_source_init(struct wlr_data_source *source,
-		const struct wlr_data_source_impl *impl) {
-	assert(impl->send);
-
-	source->impl = impl;
-	wl_array_init(&source->mime_types);
-	wl_signal_init(&source->events.destroy);
-	source->actions = -1;
-}
-
-void wlr_data_source_finish(struct wlr_data_source *source) {
-	if (source == NULL) {
-		return;
-	}
-
-	wlr_signal_emit_safe(&source->events.destroy, source);
-
-	char **p;
-	wl_array_for_each(p, &source->mime_types) {
-		free(*p);
-	}
-	wl_array_release(&source->mime_types);
-}
-
-void wlr_data_source_send(struct wlr_data_source *source, const char *mime_type,
-		int32_t fd) {
-	source->impl->send(source, mime_type, fd);
-}
-
-void wlr_data_source_accept(struct wlr_data_source *source, uint32_t serial,
-		const char *mime_type) {
-	source->accepted = (mime_type != NULL);
-	if (source->impl->accept) {
-		source->impl->accept(source, serial, mime_type);
-	}
-}
-
-void wlr_data_source_cancel(struct wlr_data_source *source) {
-	if (source->impl->cancel) {
-		source->impl->cancel(source);
-	}
-}
-
-void wlr_data_source_dnd_drop(struct wlr_data_source *source) {
-	if (source->impl->dnd_drop) {
-		source->impl->dnd_drop(source);
-	}
-}
-
-void wlr_data_source_dnd_finish(struct wlr_data_source *source) {
-	if (source->impl->dnd_finish) {
-		source->impl->dnd_finish(source);
-	}
-}
-
-void wlr_data_source_dnd_action(struct wlr_data_source *source,
-		enum wl_data_device_manager_dnd_action action) {
-	source->current_dnd_action = action;
-	if (source->impl->dnd_action) {
-		source->impl->dnd_action(source, action);
-	}
-}
-
-
-void data_device_manager_get_data_device(struct wl_client *client,
-		struct wl_resource *manager_resource, uint32_t id,
-		struct wl_resource *seat_resource) {
-	struct wlr_seat_client *seat_client =
-		wlr_seat_client_from_resource(seat_resource);
-
-	struct wl_resource *resource = wl_resource_create(client,
-		&wl_data_device_interface, wl_resource_get_version(manager_resource),
-		id);
-	if (resource == NULL) {
-		wl_resource_post_no_memory(manager_resource);
-		return;
-	}
-	wl_resource_set_implementation(resource, &data_device_impl, seat_client,
-		&data_device_destroy);
-	wl_list_insert(&seat_client->data_devices, wl_resource_get_link(resource));
-}
-
-static void data_device_manager_create_data_source(struct wl_client *client,
-		struct wl_resource *resource, uint32_t id) {
-	struct wl_resource *source_resource = wl_resource_create(client,
-		&wl_data_source_interface, wl_resource_get_version(resource), id);
-	if (source_resource == NULL) {
-		wl_resource_post_no_memory(resource);
-		return;
-	}
-
-	struct client_data_source *source =
-		client_data_source_create(source_resource);
-	if (source == NULL) {
-		wl_resource_destroy(source_resource);
-		wl_resource_post_no_memory(resource);
-		return;
-	}
-
-	wl_resource_set_implementation(source_resource, &data_source_impl,
-		source, data_source_resource_handle_destroy);
-}
-
-static const struct wl_data_device_manager_interface
-		data_device_manager_impl = {
-	.create_data_source = data_device_manager_create_data_source,
-	.get_data_device = data_device_manager_get_data_device,
-};
-
-static void data_device_manager_bind(struct wl_client *client,
-		void *data, uint32_t version, uint32_t id) {
-	struct wl_resource *resource = wl_resource_create(client,
-		&wl_data_device_manager_interface,
-		version, id);
-	if (resource == NULL) {
-		wl_client_post_no_memory(client);
-		return;
-	}
-
-	wl_resource_set_implementation(resource, &data_device_manager_impl,
-		NULL, NULL);
-}
-
-void wlr_data_device_manager_destroy(struct wlr_data_device_manager *manager) {
-	if (!manager) {
-		return;
-	}
-	wl_list_remove(&manager->display_destroy.link);
-	// TODO: free wl_resources
-	wl_global_destroy(manager->global);
-	free(manager);
-}
-
-static void handle_display_destroy(struct wl_listener *listener, void *data) {
-	struct wlr_data_device_manager *manager =
-		wl_container_of(listener, manager, display_destroy);
-	wlr_data_device_manager_destroy(manager);
-}
-
-struct wlr_data_device_manager *wlr_data_device_manager_create(
-		struct wl_display *display) {
-	struct wlr_data_device_manager *manager =
-		calloc(1, sizeof(struct wlr_data_device_manager));
-	if (manager == NULL) {
-		wlr_log(L_ERROR, "could not create data device manager");
-		return NULL;
-	}
-
-	manager->global =
-		wl_global_create(display, &wl_data_device_manager_interface,
-			3, NULL, data_device_manager_bind);
-	if (!manager->global) {
-		wlr_log(L_ERROR, "could not create data device manager wl global");
-		free(manager);
-		return NULL;
-	}
-
-	manager->display_destroy.notify = handle_display_destroy;
-	wl_display_add_destroy_listener(display, &manager->display_destroy);
-
-	return manager;
-}