Clean up inotify watch handling

Substantially based on a patch by Matthias Clasen <mclasen@redhat.com>
kqueue implementation by Joe Marcus Clarke <marcus@freebsd.org>

Previously, when we detected a configuration change (which included
the set of config directories to monitor for changes), we would
simply drop all watches, then readd them.

The problem with this is that it introduced a race condition where
we might not be watching one of the config directories for changes.

Rather than dropping and readding, change the OS-dependent monitoring
API to simply take a new set of directories to monitor.  Implicit
in this is that the OS-specific layer needs to keep track of the
previously monitored set.

1 files changed, 10 insertions, 5 deletions

diff --git a/bus/dir-watch.h b/bus/dir-watch.h
index 8e322a6e..b44529e5 100644
--- a/bus/dir-watch.h
+++ b/bus/dir-watch.h
@@ -26,10 +26,15 @@
 #ifndef DIR_WATCH_H
 #define DIR_WATCH_H
 
-/* setup a watch on a directory (OS dependent, may be a NOP) */
-void bus_watch_directory (const char *directory, BusContext *context);
-
-/* drop all the watches previously set up by bus_config_watch_directory (OS dependent, may be a NOP) */
-void bus_drop_all_directory_watches (void);
+/**
+ * Update the set of directories to monitor for changes.  The
+ * operating-system-specific implementation of this function should
+ * avoid creating a window where a directory in both the
+ * old and new set isn't monitored.
+ *
+ * @param context The bus context
+ * @param dirs List of strings which are directory paths
+ */
+void bus_set_watched_dirs (BusContext *context, DBusList **dirs);
 
 #endif /* DIR_WATCH_H */