From 9e4096146fa5a20df2fc06301683853029851163 Mon Sep 17 00:00:00 2001
From: Ingo Weinhold <ingo_weinhold@gmx.de>
Date: Mon, 8 Apr 2013 15:19:11 +0200
Subject: [PATCH] package daemon: Add a Listener interface for Volume

* This way, Volume doesn't have to know Root.
* Suppress listener notifications for node monitoring events when there
  are were already events pending.
---
 src/servers/package/Root.cpp   |  6 ++----
 src/servers/package/Root.h     | 12 +++++++-----
 src/servers/package/Volume.cpp | 29 +++++++++++++++++++++++++----
 src/servers/package/Volume.h   | 15 ++++++++++++++-
 4 files changed, 48 insertions(+), 14 deletions(-)

diff --git a/src/servers/package/Root.cpp b/src/servers/package/Root.cpp
index 6553f4bba7..f05dcc66cb 100644
--- a/src/servers/package/Root.cpp
+++ b/src/servers/package/Root.cpp
@@ -14,7 +14,6 @@
 #include <Path.h>
 
 #include "DebugSupport.h"
-#include "Volume.h"
 
 
 // #pragma mark - InitVolumePackagesJob
@@ -29,7 +28,7 @@ struct Root::InitPackagesJob : public Job {
 
 	virtual void Do()
 	{
-		fVolume->InitPackages();
+		fVolume->InitPackages(fVolume->GetRoot());
 	}
 
 private:
@@ -210,9 +209,8 @@ Root::FindVolume(dev_t deviceID) const
 
 
 void
-Root::HandleNodeMonitorEvents(Volume* volume)
+Root::VolumeNodeMonitorEventOccurred(Volume* volume)
 {
-// TODO: Don't push a new one, if one is already pending!
 	_QueueJob(new(std::nothrow) HandleNodeMonitorEventsJob(volume));
 }
 
diff --git a/src/servers/package/Root.h b/src/servers/package/Root.h
index 288f5088e9..2c7f328f08 100644
--- a/src/servers/package/Root.h
+++ b/src/servers/package/Root.h
@@ -19,12 +19,10 @@
 #include <packagefs.h>
 
 #include "JobQueue.h"
+#include "Volume.h"
 
 
-class Volume;
-
-
-class Root : public BReferenceable {
+class Root : public BReferenceable, private Volume::Listener {
 public:
 								Root();
 	virtual						~Root();
@@ -42,7 +40,9 @@ public:
 
 			Volume*				FindVolume(dev_t deviceID) const;
 
-			void				HandleNodeMonitorEvents(Volume* volume);
+private:
+	// Volume::Listener
+	virtual	void				VolumeNodeMonitorEventOccurred(Volume* volume);
 
 protected:
 	virtual	void				LastReferenceReleased();
@@ -52,6 +52,8 @@ private:
 			struct DeleteVolumeJob;
 			struct HandleNodeMonitorEventsJob;
 
+			friend struct InitPackagesJob;
+
 private:
 			Volume**			_GetVolume(PackageFSMountType mountType);
 
diff --git a/src/servers/package/Volume.cpp b/src/servers/package/Volume.cpp
index 8c330847fd..a1945c1e77 100644
--- a/src/servers/package/Volume.cpp
+++ b/src/servers/package/Volume.cpp
@@ -24,7 +24,14 @@
 #include <AutoLocker.h>
 
 #include "DebugSupport.h"
-#include "Root.h"
+
+
+// #pragma mark - Listener
+
+
+Volume::Listener::~Listener()
+{
+}
 
 
 // #pragma mark - NodeMonitorEvent
@@ -67,6 +74,7 @@ Volume::Volume(BLooper* looper)
 	fRootDirectoryRef(),
 	fPackagesDirectoryRef(),
 	fRoot(NULL),
+	fListener(NULL),
 	fPackagesByFileName(),
 	fPackagesByNodeRef(),
 	fPendingNodeMonitorEventsLock("pending node monitor events"),
@@ -78,6 +86,9 @@ Volume::Volume(BLooper* looper)
 
 Volume::~Volume()
 {
+	Unmounted();
+		// need for error case in InitPackages()
+
 	fPackagesByFileName.Clear();
 
 	Package* package = fPackagesByNodeRef.Clear(true);
@@ -153,7 +164,7 @@ Volume::Init(const node_ref& rootDirectoryRef, node_ref& _packageRootRef)
 
 
 status_t
-Volume::InitPackages()
+Volume::InitPackages(Listener* listener)
 {
 	// node-monitor the volume's packages directory
 	status_t error = watch_node(&fPackagesDirectoryRef, B_WATCH_DIRECTORY,
@@ -166,6 +177,8 @@ Volume::InitPackages()
 		// packages directory won't work correctly.
 	}
 
+	fListener = listener;
+
 	// read the packages directory and get the active packages
 	int fd = OpenRootDirectory();
 	if (fd < 0) {
@@ -190,7 +203,13 @@ Volume::InitPackages()
 void
 Volume::Unmounted()
 {
-	stop_watching(BMessenger(this));
+	if (fListener != NULL) {
+		stop_watching(BMessenger(this));
+		fListener = NULL;
+	}
+
+	if (BLooper* looper = Looper())
+		looper->RemoveHandler(this);
 }
 
 
@@ -324,10 +343,12 @@ Volume::_QueueNodeMonitorEvent(const BString& name, bool wasCreated)
 	}
 
 	AutoLocker<BLocker> eventsLock(fPendingNodeMonitorEventsLock);
+	bool firstEvent = fPendingNodeMonitorEvents.IsEmpty();
 	fPendingNodeMonitorEvents.Add(event);
 	eventsLock.Unlock();
 
-	fRoot->HandleNodeMonitorEvents(this);
+	if (firstEvent && fListener != NULL)
+		fListener->VolumeNodeMonitorEventOccurred(this);
 }
 
 
diff --git a/src/servers/package/Volume.h b/src/servers/package/Volume.h
index c791cae258..24eab04c6d 100644
--- a/src/servers/package/Volume.h
+++ b/src/servers/package/Volume.h
@@ -25,13 +25,16 @@ class Root;
 
 
 class Volume : public BHandler {
+public:
+			class Listener;
+
 public:
 								Volume(BLooper* looper);
 	virtual						~Volume();
 
 			status_t			Init(const node_ref& rootDirectoryRef,
 									node_ref& _packageRootRef);
-			status_t			InitPackages();
+			status_t			InitPackages(Listener* listener);
 
 			void				Unmounted();
 
@@ -88,6 +91,7 @@ private:
 			node_ref			fRootDirectoryRef;
 			node_ref			fPackagesDirectoryRef;
 			Root*				fRoot;
+			Listener*			fListener;
 			PackageFileNameHashTable fPackagesByFileName;
 			PackageNodeRefHashTable fPackagesByNodeRef;
 			BLocker				fPendingNodeMonitorEventsLock;
@@ -95,4 +99,13 @@ private:
 };
 
 
+class Volume::Listener {
+public:
+	virtual						~Listener();
+
+	virtual	void				VolumeNodeMonitorEventOccurred(Volume* volume)
+									= 0;
+};
+
+
 #endif	// VOLUME_H