Bugfix: use restore_conn, not conn

Using the wrong X11 connection breaks the libev event handling model:
xcb_flush() must be called immediately before handing control to libev.

Before this fix:

1. xcb_prepare_cb would read and flush conn
2. restore_xcb_prepare_cb would read and flush restore_conn,
   BUT also inadvertantly call xcb_flush(conn), resulting in new
   events being filled into the XCB event queue
3. libev waits for new events
4. after 1 minute, libev times out and the events are processed

Diagnosed using strace on testcases/complete-run.pl.

related to commit 0d8b6714e3

related to #3510
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Michael Stapelberg 2018-12-08 13:31:53 +01:00
parent 620e90bed8
commit 01c1b5dec2
1 changed files with 3 additions and 3 deletions

View File

@ -180,8 +180,8 @@ static void update_placeholder_contents(placeholder_state *state) {
int y = (state->rect.height / 2) - (config.font.height / 2);
draw_util_text(line, &(state->surface), foreground, background, x, y, text_width);
i3string_free(line);
xcb_flush(conn);
xcb_aux_sync(conn);
xcb_flush(restore_conn);
xcb_aux_sync(restore_conn);
}
static void open_placeholder_window(Con *con) {
@ -221,7 +221,7 @@ static void open_placeholder_window(Con *con) {
state->con = con;
state->rect = con->rect;
draw_util_surface_init(conn, &(state->surface), placeholder, get_visualtype(root_screen), state->rect.width, state->rect.height);
draw_util_surface_init(restore_conn, &(state->surface), placeholder, get_visualtype(root_screen), state->rect.width, state->rect.height);
update_placeholder_contents(state);
TAILQ_INSERT_TAIL(&state_head, state, state);