Merge pull request #760 from emersion/xwayland-dnd

xwayland: add drag'n'drop support

1 files changed, 319 insertions, 0 deletions

diff --git a/xwayland/selection/selection.c b/xwayland/selection/selection.c
new file mode 100644
index 00000000..39c47c45
--- /dev/null
+++ b/xwayland/selection/selection.c
@@ -0,0 +1,319 @@
+#define _XOPEN_SOURCE 700
+#include <assert.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <wlr/types/wlr_data_device.h>
+#include <wlr/types/wlr_primary_selection.h>
+#include <wlr/util/log.h>
+#include <xcb/xfixes.h>
+#include "xwayland/xwm.h"
+#include "xwayland/selection.h"
+
+void xwm_selection_transfer_remove_source(
+		struct wlr_xwm_selection_transfer *transfer) {
+	if (transfer->source != NULL) {
+		wl_event_source_remove(transfer->source);
+		transfer->source = NULL;
+	}
+}
+
+void xwm_selection_transfer_close_source_fd(
+		struct wlr_xwm_selection_transfer *transfer) {
+	if (transfer->source_fd >= 0) {
+		close(transfer->source_fd);
+		transfer->source_fd = -1;
+	}
+}
+
+void xwm_selection_transfer_destroy_property_reply(
+		struct wlr_xwm_selection_transfer *transfer) {
+	free(transfer->property_reply);
+	transfer->property_reply = NULL;
+}
+
+xcb_atom_t xwm_mime_type_to_atom(struct wlr_xwm *xwm, char *mime_type) {
+	if (strcmp(mime_type, "text/plain;charset=utf-8") == 0) {
+		return xwm->atoms[UTF8_STRING];
+	} else if (strcmp(mime_type, "text/plain") == 0) {
+		return xwm->atoms[TEXT];
+	}
+
+	xcb_intern_atom_cookie_t cookie =
+		xcb_intern_atom(xwm->xcb_conn, 0, strlen(mime_type), mime_type);
+	xcb_intern_atom_reply_t *reply =
+		xcb_intern_atom_reply(xwm->xcb_conn, cookie, NULL);
+	if (reply == NULL) {
+		return XCB_ATOM_NONE;
+	}
+	xcb_atom_t atom = reply->atom;
+	free(reply);
+	return atom;
+}
+
+char *xwm_mime_type_from_atom(struct wlr_xwm *xwm, xcb_atom_t atom) {
+	if (atom == xwm->atoms[UTF8_STRING]) {
+		return strdup("text/plain;charset=utf-8");
+	} else if (atom == xwm->atoms[TEXT]) {
+		return strdup("text/plain");
+	} else {
+		return xwm_get_atom_name(xwm, atom);
+	}
+}
+
+struct wlr_xwm_selection *xwm_get_selection(struct wlr_xwm *xwm,
+		xcb_atom_t selection_atom) {
+	if (selection_atom == xwm->atoms[CLIPBOARD]) {
+		return &xwm->clipboard_selection;
+	} else if (selection_atom == xwm->atoms[PRIMARY]) {
+		return &xwm->primary_selection;
+	} else if (selection_atom == xwm->atoms[DND_SELECTION]) {
+		return &xwm->dnd_selection;
+	} else {
+		return NULL;
+	}
+}
+
+static int xwm_handle_selection_property_notify(struct wlr_xwm *xwm,
+		xcb_property_notify_event_t *event) {
+	struct wlr_xwm_selection *selections[] = {
+		&xwm->clipboard_selection,
+		&xwm->primary_selection,
+		&xwm->dnd_selection,
+	};
+
+	for (size_t i = 0; i < sizeof(selections)/sizeof(selections[0]); ++i) {
+		struct wlr_xwm_selection *selection = selections[i];
+
+		if (event->window == selection->window) {
+			if (event->state == XCB_PROPERTY_NEW_VALUE &&
+					event->atom == xwm->atoms[WL_SELECTION] &&
+					selection->incoming.incr) {
+				xwm_get_incr_chunk(&selection->incoming);
+			}
+			return 1;
+		}
+
+		struct wlr_xwm_selection_transfer *outgoing;
+		wl_list_for_each(outgoing, &selection->outgoing, outgoing_link) {
+			if (event->window == outgoing->request.requestor) {
+				if (event->state == XCB_PROPERTY_DELETE &&
+						event->atom == outgoing->request.property &&
+						outgoing->incr) {
+					xwm_send_incr_chunk(outgoing);
+				}
+				return 1;
+			}
+		}
+	}
+
+	return 0;
+}
+
+int xwm_handle_selection_event(struct wlr_xwm *xwm,
+		xcb_generic_event_t *event) {
+	if (xwm->seat == NULL) {
+		wlr_log(L_DEBUG, "not handling selection events: "
+			"no seat assigned to xwayland");
+		return 0;
+	}
+
+	switch (event->response_type & XCB_EVENT_RESPONSE_TYPE_MASK) {
+	case XCB_SELECTION_NOTIFY:
+		xwm_handle_selection_notify(xwm, (xcb_selection_notify_event_t *)event);
+		return 1;
+	case XCB_PROPERTY_NOTIFY:
+		return xwm_handle_selection_property_notify(xwm,
+			(xcb_property_notify_event_t *)event);
+	case XCB_SELECTION_REQUEST:
+		xwm_handle_selection_request(xwm,
+			(xcb_selection_request_event_t *)event);
+		return 1;
+	}
+
+	switch (event->response_type - xwm->xfixes->first_event) {
+	case XCB_XFIXES_SELECTION_NOTIFY:
+		// an X11 window has copied something to the clipboard
+		return xwm_handle_xfixes_selection_notify(xwm,
+			(xcb_xfixes_selection_notify_event_t *)event);
+	}
+
+	return 0;
+}
+
+static void selection_init(struct wlr_xwm *xwm,
+		struct wlr_xwm_selection *selection, xcb_atom_t atom) {
+	selection->xwm = xwm;
+	selection->atom = atom;
+	selection->window = xwm->selection_window;
+	selection->incoming.selection = selection;
+	wl_list_init(&selection->outgoing);
+
+	uint32_t mask =
+		XCB_XFIXES_SELECTION_EVENT_MASK_SET_SELECTION_OWNER |
+		XCB_XFIXES_SELECTION_EVENT_MASK_SELECTION_WINDOW_DESTROY |
+		XCB_XFIXES_SELECTION_EVENT_MASK_SELECTION_CLIENT_CLOSE;
+	xcb_xfixes_select_selection_input(xwm->xcb_conn, selection->window,
+		selection->atom, mask);
+}
+
+void xwm_selection_init(struct wlr_xwm *xwm) {
+	// Clipboard and primary selection
+	uint32_t selection_values[] = {
+		XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY | XCB_EVENT_MASK_PROPERTY_CHANGE
+	};
+	xwm->selection_window = xcb_generate_id(xwm->xcb_conn);
+	xcb_create_window(xwm->xcb_conn,
+		XCB_COPY_FROM_PARENT,
+		xwm->selection_window,
+		xwm->screen->root,
+		0, 0,
+		10, 10,
+		0,
+		XCB_WINDOW_CLASS_INPUT_OUTPUT,
+		xwm->screen->root_visual,
+		XCB_CW_EVENT_MASK, selection_values);
+
+	xcb_set_selection_owner(xwm->xcb_conn,
+		xwm->selection_window,
+		xwm->atoms[CLIPBOARD_MANAGER],
+		XCB_TIME_CURRENT_TIME);
+
+	selection_init(xwm, &xwm->clipboard_selection, xwm->atoms[CLIPBOARD]);
+	selection_init(xwm, &xwm->primary_selection, xwm->atoms[PRIMARY]);
+
+	// Drag'n'drop
+	uint32_t dnd_values[] = {
+		XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY | XCB_EVENT_MASK_PROPERTY_CHANGE
+	};
+	xwm->dnd_window = xcb_generate_id(xwm->xcb_conn);
+	xcb_create_window(xwm->xcb_conn,
+		XCB_COPY_FROM_PARENT,
+		xwm->dnd_window,
+		xwm->screen->root,
+		0, 0,
+		8192, 8192,
+		0,
+		XCB_WINDOW_CLASS_INPUT_ONLY,
+		xwm->screen->root_visual,
+		XCB_CW_EVENT_MASK, dnd_values);
+
+	uint32_t version = XDND_VERSION;
+	xcb_change_property(xwm->xcb_conn,
+		XCB_PROP_MODE_REPLACE,
+		xwm->dnd_window,
+		xwm->atoms[DND_AWARE],
+		XCB_ATOM_ATOM,
+		32, // format
+		1, &version);
+
+	selection_init(xwm, &xwm->dnd_selection, xwm->atoms[DND_SELECTION]);
+}
+
+void xwm_selection_finish(struct wlr_xwm *xwm) {
+	if (!xwm) {
+		return;
+	}
+	if (xwm->selection_window) {
+		xcb_destroy_window(xwm->xcb_conn, xwm->selection_window);
+	}
+	if (xwm->dnd_window) {
+		xcb_destroy_window(xwm->xcb_conn, xwm->dnd_window);
+	}
+	if (xwm->seat) {
+		if (xwm->seat->selection_source &&
+				wlr_data_source_is_xwayland_data_source(
+					xwm->seat->selection_source)) {
+			wlr_seat_set_selection(xwm->seat, NULL,
+				wl_display_next_serial(xwm->xwayland->wl_display));
+		}
+		if (xwm->seat->primary_selection_source &&
+				wlr_primary_selection_source_is_xwayland_primary_selection_source(
+					xwm->seat->primary_selection_source)) {
+			wlr_seat_set_primary_selection(xwm->seat, NULL,
+				wl_display_next_serial(xwm->xwayland->wl_display));
+		}
+		wlr_xwayland_set_seat(xwm->xwayland, NULL);
+	}
+}
+
+static void xwm_selection_set_owner(struct wlr_xwm_selection *selection,
+		bool set) {
+	if (set) {
+		xcb_set_selection_owner(selection->xwm->xcb_conn,
+			selection->window,
+			selection->atom,
+			XCB_TIME_CURRENT_TIME);
+	} else {
+		if (selection->owner == selection->window) {
+			xcb_set_selection_owner(selection->xwm->xcb_conn,
+				XCB_WINDOW_NONE,
+				selection->atom,
+				selection->timestamp);
+		}
+	}
+}
+
+static void seat_handle_selection(struct wl_listener *listener,
+		void *data) {
+	struct wlr_seat *seat = data;
+	struct wlr_xwm *xwm =
+		wl_container_of(listener, xwm, seat_selection);
+	struct wlr_data_source *source = seat->selection_source;
+
+	if (source != NULL && wlr_data_source_is_xwayland_data_source(source)) {
+		return;
+	}
+
+	xwm_selection_set_owner(&xwm->clipboard_selection, source != NULL);
+}
+
+static void seat_handle_primary_selection(struct wl_listener *listener,
+		void *data) {
+	struct wlr_seat *seat = data;
+	struct wlr_xwm *xwm =
+		wl_container_of(listener, xwm, seat_primary_selection);
+	struct wlr_primary_selection_source *source = seat->primary_selection_source;
+
+	if (source != NULL &&
+			wlr_primary_selection_source_is_xwayland_primary_selection_source(
+				source)) {
+		return;
+	}
+
+	xwm_selection_set_owner(&xwm->primary_selection, source != NULL);
+}
+
+static void seat_handle_start_drag(struct wl_listener *listener, void *data) {
+	struct wlr_xwm *xwm = wl_container_of(listener, xwm, seat_start_drag);
+	struct wlr_drag *drag = data;
+
+	xwm_selection_set_owner(&xwm->dnd_selection, drag != NULL);
+	xwm_seat_handle_start_drag(xwm, drag);
+}
+
+void xwm_set_seat(struct wlr_xwm *xwm, struct wlr_seat *seat) {
+	if (xwm->seat != NULL) {
+		wl_list_remove(&xwm->seat_selection.link);
+		wl_list_remove(&xwm->seat_primary_selection.link);
+		wl_list_remove(&xwm->seat_start_drag.link);
+		xwm->seat = NULL;
+	}
+
+	if (seat == NULL) {
+		return;
+	}
+
+	xwm->seat = seat;
+
+	wl_signal_add(&seat->events.selection, &xwm->seat_selection);
+	xwm->seat_selection.notify = seat_handle_selection;
+	wl_signal_add(&seat->events.primary_selection, &xwm->seat_primary_selection);
+	xwm->seat_primary_selection.notify = seat_handle_primary_selection;
+	wl_signal_add(&seat->events.start_drag, &xwm->seat_start_drag);
+	xwm->seat_start_drag.notify = seat_handle_start_drag;
+
+	seat_handle_selection(&xwm->seat_selection, seat);
+	seat_handle_primary_selection(&xwm->seat_primary_selection, seat);
+}