From dea94f2bad74bf3edf8ff9c44191c076b23efa23 Mon Sep 17 00:00:00 2001 From: Tudor Brindus Date: Mon, 25 Jan 2021 20:29:33 -0500 Subject: [PATCH] xwayland/selection: simplify incremental transfer control flow Previously, if the Wayland client died before an incremental transfer was complete, the logs would be spammed by "write error to target fd" as wlroots entered some control flow wherein it'd continually try scheduling further writes to the already-dead pipe. This commit contains no behavioral changes, but introduces explicit handling for draining the X11 selection in case of Wayland client death. --- xwayland/selection/incoming.c | 38 +++++++++++++++++++++++++---------- 1 file changed, 27 insertions(+), 11 deletions(-) diff --git a/xwayland/selection/incoming.c b/xwayland/selection/incoming.c index 1fae0df6..5088e9b2 100644 --- a/xwayland/selection/incoming.c +++ b/xwayland/selection/incoming.c @@ -11,12 +11,21 @@ #include "xwayland/selection.h" #include "xwayland/xwm.h" +static void xwm_notify_ready_for_next_incr_chunk( + struct wlr_xwm_selection_transfer *transfer) { + struct wlr_xwm *xwm = transfer->selection->xwm; + assert(transfer->incr); + wlr_log(WLR_DEBUG, "deleting property"); + xcb_delete_property(xwm->xcb_conn, transfer->selection->window, + xwm->atoms[WL_SELECTION]); + xcb_flush(xwm->xcb_conn); +} + /** * Write the X11 selection to a Wayland client. */ static int xwm_data_source_write(int fd, uint32_t mask, void *data) { struct wlr_xwm_selection_transfer *transfer = data; - struct wlr_xwm *xwm = transfer->selection->xwm; char *property = xcb_get_property_value(transfer->property_reply); int remainder = xcb_get_property_value_length(transfer->property_reply) - @@ -35,16 +44,14 @@ static int xwm_data_source_write(int fd, uint32_t mask, void *data) { transfer->property_start + len, len, xcb_get_property_value_length(transfer->property_reply)); - transfer->property_start += len; - if (len == remainder) { + if (len < remainder) { + transfer->property_start += len; + } else { xwm_selection_transfer_destroy_property_reply(transfer); xwm_selection_transfer_remove_event_source(transfer); if (transfer->incr) { - wlr_log(WLR_DEBUG, "deleting property"); - xcb_delete_property(xwm->xcb_conn, transfer->selection->window, - xwm->atoms[WL_SELECTION]); - xcb_flush(xwm->xcb_conn); + xwm_notify_ready_for_next_incr_chunk(transfer); } else { wlr_log(WLR_DEBUG, "transfer complete"); xwm_selection_transfer_close_wl_client_fd(transfer); @@ -97,11 +104,20 @@ void xwm_get_incr_chunk(struct wlr_xwm_selection_transfer *transfer) { //dump_property(xwm, xwm->atoms[WL_SELECTION], reply); if (xcb_get_property_value_length(reply) > 0) { - /* Reply's ownership is transferred to xwm, which is responsible - * for freeing it */ - xwm_write_property(transfer, reply); + // Reply's ownership is transferred to xwm, which is responsible + // for freeing it. + if (transfer->wl_client_fd >= 0) { + // Wayland client is alive, property will be freed once it has finished + // reading it. + xwm_write_property(transfer, reply); + } else { + // Wayland client closed its pipe prematurely (or died). Continue draining + // the X11 client. + xwm_notify_ready_for_next_incr_chunk(transfer); + free(reply); + } } else { - wlr_log(WLR_DEBUG, "transfer complete"); + wlr_log(WLR_DEBUG, "incremental transfer complete"); xwm_selection_transfer_close_wl_client_fd(transfer); free(reply); }