From 99f8c085594dba25006fa29fbfb09b60105bbaf9 Mon Sep 17 00:00:00 2001 From: Semi Malinen Date: Wed, 2 May 2018 11:10:32 +0200 Subject: [PATCH] desktop-shell: detect stale shell surface outputs When displays are hot (un)plugged, it may happen that a shell surface is left with a stale pointer to an output that has already been freed. Add an output destroy listener to catch such situations and set the output pointer to NULL. Signed-off-by: Semi Malinen Signed-off-by: Fabien Lahoudere Reviewed-by: Pekka Paalanen --- desktop-shell/shell.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/desktop-shell/shell.c b/desktop-shell/shell.c index 1e153cb53..64db89fc2 100644 --- a/desktop-shell/shell.c +++ b/desktop-shell/shell.c @@ -128,6 +128,7 @@ struct shell_surface { struct weston_output *fullscreen_output; struct weston_output *output; + struct wl_listener output_destroy_listener; struct surface_state { bool fullscreen; @@ -1933,6 +1934,17 @@ shell_surface_update_layer(struct shell_surface *shsurf) shell_surface_update_child_surface_layers(shsurf); } +static void +notify_output_destroy(struct wl_listener *listener, void *data) +{ + struct shell_surface *shsurf = + container_of(listener, + struct shell_surface, output_destroy_listener); + + shsurf->output = NULL; + shsurf->output_destroy_listener.notify = NULL; +} + static void shell_surface_set_output(struct shell_surface *shsurf, struct weston_output *output) @@ -1948,6 +1960,18 @@ shell_surface_set_output(struct shell_surface *shsurf, shsurf->output = es->output; else shsurf->output = get_default_output(es->compositor); + + if (shsurf->output_destroy_listener.notify) { + wl_list_remove(&shsurf->output_destroy_listener.link); + shsurf->output_destroy_listener.notify = NULL; + } + + if (!shsurf->output) + return; + + shsurf->output_destroy_listener.notify = notify_output_destroy; + wl_signal_add(&shsurf->output->destroy_signal, + &shsurf->output_destroy_listener); } static void @@ -1986,7 +2010,7 @@ unset_maximized(struct shell_surface *shsurf) weston_desktop_surface_get_surface(shsurf->desktop_surface); /* undo all maximized things here */ - shsurf->output = get_default_output(surface->compositor); + shell_surface_set_output(shsurf, get_default_output(surface->compositor)); if (shsurf->saved_position_valid) weston_view_set_position(shsurf->view, @@ -2348,7 +2372,8 @@ desktop_surface_added(struct weston_desktop_surface *desktop_surface, shsurf->fullscreen.black_view = NULL; wl_list_init(&shsurf->fullscreen.transform.link); - shsurf->output = get_default_output(shsurf->shell->compositor); + shell_surface_set_output( + shsurf, get_default_output(shsurf->shell->compositor)); wl_signal_init(&shsurf->destroy_signal);