kiosk-shell: Keep track of seats created and destroy them at end

kiosk_shell_destroy() will free up weston_desktop, but still keeping listeners set-up (keyboard/seat/caps), which will fire when the the compositor is stopped/shutdown by clients still connected.

This patch maintains a list of seats and uses it to remove any listeners when calling kiosk_shell_destroy(). desktop-shell and ivi-shell do not appear to be using weston_desktop_destroy() in their respective destroy parts.

This avoids an illegal access happening when calling one of the listeners, after weston_desktop has been free'ed, like the following:

==2002== at 0x10F3F8FD: weston_desktop_get_display (libweston-desktop.c:125) ==2002== by 0x10F450A7: weston_desktop_xdg_surface_schedule_configure (xdg-shell.c:1022) ==2002== by 0x10F44793: weston_desktop_xdg_toplevel_set_activated (xdg-shell.c:643) ==2002== by 0x10F41AA5: weston_desktop_surface_set_activated (surface.c:468) ==2002== by 0x10F32E7E: kiosk_shell_seat_handle_keyboard_focus (kiosk-shell.c:329) ==2002== by 0x4A726A7: wl_signal_emit (wayland-server-core.h:478) ==2002== by 0x4A75BD1: weston_keyboard_set_focus (input.c:1586) ==2002== by 0x4A776FE: notify_keyboard_focus_out (input.c:2314) ==2002== by 0x5902BC1: udev_seat_destroy (libinput-seat.c:469) ==2002== by 0x59028C5: udev_input_destroy (libinput-seat.c:375) ==2002== by 0x58F0449: drm_destroy (drm.c:2571) ==2002== by 0x4A6EE39: weston_compositor_destroy (compositor.c:7814) ==2002== Address 0x10bd1780 is 0 bytes inside a block of size 152 free'd ==2002== at 0x48399AB: free (vg_replace_malloc.c:538) ==2002== by 0x10F3F8DA: weston_desktop_destroy (libweston-desktop.c:112) ==2002== by 0x10F34357: kiosk_shell_destroy (kiosk-shell.c:1009) ==2002== by 0x4A5F618: wl_signal_emit (wayland-server-core.h:478) ==2002== by 0x4A6EE06: weston_compositor_destroy (compositor.c:7809) ==2002== by 0x4855548: wet_main (main.c:3420) ==2002== by 0x109154: main (executable.c:33) ==2002== Block was alloc'd at ==2002== at 0x483AB65: calloc (vg_replace_malloc.c:760) ==2002== by 0x10F3F681: zalloc (zalloc.h:38) ==2002== by 0x10F3F724: weston_desktop_create (libweston-desktop.c:65) ==2002== by 0x10F34458: wet_shell_init (kiosk-shell.c:1045) ==2002== by 0x484F83D: wet_load_shell (main.c:924) ==2002== by 0x48552D3: wet_main (main.c:3361) ==2002== by 0x109154: main (executable.c:33)

Signed-off-by: Marius Vlad marius.vlad@collabora.com

/cc @afrantzis