BQuery: Make SetFlags() behave like other Set..() methods & add documentation.

docs/user/storage/Query.dox

@@ -330,6 +330,27 @@
 */
 
 
+/*!
+	\fn status_t BQuery::SetFlags(uint32 flags)
+	\brief Sets the flags the query will be opened with.
+
+	The possible flags to set are defined in \file fs_query.h.
+
+	This methods fails if called after Fetch(). To reuse the BQuery object it
+	must first be reset via Clear().
+
+	\note The \c B_LIVE_QUERY flag will be ignored; BQuery always sets it automatically if necessary.
+
+	\param flags The flags to set.
+
+	\return A status code.
+	\retval B_OK Everything went fine.
+	\retval B_NOT_ALLOWED SetFlags() was called after Fetch().
+
+	\since Haiku R1
+*/
+
+
 //! @}
 
 

headers/os/storage/Query.h

@@ -63,7 +63,7 @@ public:
 			status_t		SetVolume(const BVolume* volume);
 			status_t		SetPredicate(const char* expression);
 			status_t		SetTarget(BMessenger messenger);
-			void			SetFlags(uint32 flags);
+			status_t		SetFlags(uint32 flags);
 
 			bool			IsLive() const;
 

src/kits/storage/Query.cpp

@@ -231,10 +231,14 @@ BQuery::SetTarget(BMessenger messenger)
 }
 
 
-void
+status_t
 BQuery::SetFlags(uint32 flags)
 {
-	fFlags = flags;
+	if (_HasFetched())
+		return B_NOT_ALLOWED;
+
+	fFlags = (flags & ~B_LIVE_QUERY);
+	return B_OK;
 }