notify_inotify: Map inotify mask back to filter

Instead of reporting that an inotify event triggered all possible filter
masks, map the inotify event back to the filter mask. This is slightly
more accurate, although there can still be mismatches due to the
mapping.

Signed-off-by: Christof Schmitt <cs@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>

Autobuild-User(master): Volker Lendecke <vl@samba.org>
Autobuild-Date(master): Mon Jul 18 18:50:55 CEST 2016 on sn-devel-144

1 files changed, 31 insertions, 4 deletions

diff --git a/source3/smbd/notify_inotify.c b/source3/smbd/notify_inotify.c
index f7034f1f355..3848dd67056 100644
--- a/source3/smbd/notify_inotify.c
+++ b/source3/smbd/notify_inotify.c
@@ -88,6 +88,30 @@ static uint32_t inotify_map(uint32_t *filter)
 }
 
 /*
+ * Map inotify mask back to filter. This returns all filters that
+ * could have created the inotify watch.
+ */
+static uint32_t inotify_map_mask_to_filter(uint32_t mask)
+{
+	int i;
+	uint32_t filter = 0;
+
+	for (i = 0; i < ARRAY_SIZE(inotify_mapping); i++) {
+		if (inotify_mapping[0].inotify_mask & mask) {
+			filter |= inotify_mapping[i].notify_mask;
+		}
+	}
+
+	if (mask & IN_ISDIR) {
+		filter &= ~FILE_NOTIFY_CHANGE_FILE_NAME;
+	} else {
+		filter &= ~FILE_NOTIFY_CHANGE_DIR_NAME;
+	}
+
+	return filter;
+}
+
+/*
   destroy the inotify private context
 */
 static int inotify_destructor(struct inotify_private *in)
@@ -153,6 +177,7 @@ static void inotify_dispatch(struct inotify_private *in,
 {
 	struct inotify_watch_context *w, *next;
 	struct notify_event ne;
+	uint32_t filter;
 
 	DEBUG(10, ("inotify_dispatch called with mask=%x, name=[%s]\n",
 		   e->mask, e->len ? e->name : ""));
@@ -187,15 +212,17 @@ static void inotify_dispatch(struct inotify_private *in,
 	}
 	ne.path = e->name;
 
-	DEBUG(10, ("inotify_dispatch: ne.action = %d, ne.path = %s\n",
-		   ne.action, ne.path));
+	filter = inotify_map_mask_to_filter(e->mask);
+
+	DBG_DEBUG("ne.action = %d, ne.path = %s, filter = %d\n",
+		  ne.action, ne.path, filter);
 
 	/* find any watches that have this watch descriptor */
 	for (w=in->watches;w;w=next) {
 		next = w->next;
 		if (w->wd == e->wd && filter_match(w, e)) {
 			ne.dir = w->path;
-			w->callback(in->ctx, w->private_data, &ne, UINT32_MAX);
+			w->callback(in->ctx, w->private_data, &ne, filter);
 		}
 	}
 
@@ -217,7 +244,7 @@ static void inotify_dispatch(struct inotify_private *in,
 			    !(w->filter & FILE_NOTIFY_CHANGE_CREATION)) {
 				ne.dir = w->path;
 				w->callback(in->ctx, w->private_data, &ne,
-					    UINT32_MAX);
+					    filter);
 			}
 		}
 	}