• Allison Karlitskaya's avatar
    glocalfile: add private worker monitor APIs · 33762a41
    Allison Karlitskaya authored
    Add a convenient and race-free method of watching local files from the
    GLib worker thread.
    
    Without this, the race-free way to create a monitor that dispatches
    events to the worker thread looked something like this:
    
     - dispatch an idle to the worker thread
     - from the idle, create the monitor and connect signals
     - from the original thread, wait (on a cond?) until the worker thread
       has finished setting up the monitor
     - read the file that you were monitoring
    
    which is just ridiculously complicated...
    
    To use the new API:
    
      monitor = g_local_file_monitor_new_in_worker ("/path/to/some/file",
                                                    G_FILE_MONITOR_NONE,
                                                    &error);
      g_assert_no_error (error);
    
      g_signal_connect (monitor, "changed", G_CALLBACK (callback), NULL);
    
      g_local_file_monitor_start (monitor);
    
    'callback' will run from the GLib worker thread.
    
    This is the reason that the start() call was introduced in the previous
    commit.  The backends that don't use the start() call will have a very
    thin race between creating the monitor and connecting the signal, but
    hopefully they will be fixed soon.
    
    These new APIs will be used (at least) from gdesktopappinfo to watch for
    changes in the desktop file directories.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=704887
    33762a41
glocaldirectorymonitor.h 3.49 KB