Add watching support for installation location package changes

Can be requested/stopped via BPackageRoster::{Start,Stop}Watching().
The notification message has the what code B_PACKAGE_UPDATE and contains
fields "event", "location", and "change count".

headers/os/app/AppDefs.h

@@ -48,6 +48,7 @@ enum {
 	B_MOUSE_UP 					= '_MUP',
 	B_MOUSE_WHEEL_CHANGED		= '_MWC',
 	B_OPEN_IN_WORKSPACE			= '_OWS',
+	B_PACKAGE_UPDATE			= '_PKU',
 	B_PRINTER_CHANGED			= '_PCH',
 	B_PULSE 					= '_PUL',
 	B_READY_TO_RUN 				= '_RTR',

headers/os/package/PackageRoster.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011, Haiku, Inc.
+ * Copyright 2011-2014, Haiku, Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef _PACKAGE__PACKAGE_ROSTER_H_
@@ -34,6 +34,23 @@ class BRepositoryCache;
 class BRepositoryConfig;
 
 
+// watchable events
+enum {
+	B_WATCH_PACKAGE_INSTALLATION_LOCATIONS	= 0x0001,
+		// de-/activation of packages in standard installation locations
+};
+
+// notification message "event" field values
+enum {
+	B_INSTALLATION_LOCATION_PACKAGES_CHANGED,
+		// "location": int32
+		//		the installation location
+		//		(B_PACKAGE_INSTALLATION_LOCATION_{SYSTEM,HOME}
+		// "change count": int64
+		//		the installation location change count
+};
+
+
 class BPackageRoster {
 public:
 								BPackageRoster();
@@ -68,6 +85,10 @@ class BPackageRoster {
 									BPackageInstallationLocation location,
 									BPackageInfoSet& packageInfos);
 
+			status_t			StartWatching(const BMessenger& target,
+									uint32 eventMask);
+			status_t			StopWatching(const BMessenger& target);
+
 private:
 			status_t			_GetRepositoryPath(BPath* path, bool create,
 									directory_which whichDir) const;

headers/private/app/RegistrarDefs.h

@@ -124,6 +124,10 @@ enum {
 	B_REG_DELETE_USER						= 'rdus',
 	B_REG_UPDATE_GROUP						= 'rugr',
 	B_REG_DELETE_GROUP						= 'rdgr',
+
+	// package watching requests
+	B_REG_PACKAGE_START_WATCHING			= 'rgPw',
+	B_REG_PACKAGE_STOP_WATCHING				= 'rgPx',
 };
 
 // B_REG_MIME_SET_PARAM "which" constants

src/kits/package/Jamfile

@@ -1,6 +1,7 @@
 SubDir HAIKU_TOP src kits package ;
 
 UsePrivateHeaders
+	app
 	kernel
 	shared
 	storage

src/kits/package/PackageRoster.cpp

@@ -31,6 +31,8 @@
 
 #if defined(__HAIKU__) && !defined(HAIKU_HOST_PLATFORM_HAIKU)
 #	include <package/DaemonClient.h>
+#	include <RegistrarDefs.h>
+#	include <RosterPrivate.h>
 #endif
 
 
@@ -225,6 +227,74 @@ BPackageRoster::GetActivePackages(BPackageInstallationLocation location,
 }
 
 
+status_t
+BPackageRoster::StartWatching(const BMessenger& target, uint32 eventMask)
+{
+// This method makes sense only on an installed Haiku, but not for the build
+// tools.
+#if defined(__HAIKU__) && !defined(HAIKU_HOST_PLATFORM_HAIKU)
+	// compose the registrar request
+	BMessage request(::BPrivate::B_REG_PACKAGE_START_WATCHING);
+	status_t error;
+	if ((error = request.AddMessenger("target", target)) != B_OK
+		|| (error = request.AddUInt32("events", eventMask)) != B_OK) {
+		return error;
+	}
+
+	// send it
+	BMessage reply;
+	error = BRoster::Private().SendTo(&request, &reply, false);
+	if (error != B_OK)
+		return error;
+
+	// get result
+	if (reply.what != ::BPrivate::B_REG_SUCCESS) {
+		int32 result;
+		if (reply.FindInt32("error", &result) != B_OK)
+			result = B_ERROR;
+		return (status_t)error;
+	}
+
+	return B_OK;
+#else
+	return B_NOT_SUPPORTED;
+#endif
+}
+
+
+status_t
+BPackageRoster::StopWatching(const BMessenger& target)
+{
+// This method makes sense only on an installed Haiku, but not for the build
+// tools.
+#if defined(__HAIKU__) && !defined(HAIKU_HOST_PLATFORM_HAIKU)
+	// compose the registrar request
+	BMessage request(::BPrivate::B_REG_PACKAGE_STOP_WATCHING);
+	status_t error = request.AddMessenger("target", target);
+	if (error  != B_OK)
+		return error;
+
+	// send it
+	BMessage reply;
+	error = BRoster::Private().SendTo(&request, &reply, false);
+	if (error != B_OK)
+		return error;
+
+	// get result
+	if (reply.what != ::BPrivate::B_REG_SUCCESS) {
+		int32 result;
+		if (reply.FindInt32("error", &result) != B_OK)
+			result = B_ERROR;
+		return (status_t)error;
+	}
+
+	return B_OK;
+#else
+	return B_NOT_SUPPORTED;
+#endif
+}
+
+
 status_t
 BPackageRoster::_GetRepositoryPath(BPath* path, bool create,
 	directory_which whichDir) const

src/servers/package/Volume.cpp

@@ -22,8 +22,10 @@
 #include <MessageRunner.h>
 #include <NodeMonitor.h>
 #include <Path.h>
+#include <Roster.h>
 
 #include <package/CommitTransactionResult.h>
+#include <package/PackageRoster.h>
 #include <package/solver/Solver.h>
 #include <package/solver/SolverPackage.h>
 #include <package/solver/SolverProblem.h>
@@ -35,12 +37,14 @@
 #include <AutoLocker.h>
 #include <NotOwningEntryRef.h>
 #include <package/DaemonDefs.h>
+#include <RosterPrivate.h>
 
 #include "CommitTransactionHandler.h"
 #include "Constants.h"
 #include "DebugSupport.h"
 #include "Exception.h"
 #include "PackageFileManager.h"
+#include "Root.h"
 #include "VolumeState.h"
 
 
@@ -1193,6 +1197,19 @@ Volume::_SetLatestState(VolumeState* state, bool isActive)
 	delete fLatestState;
 	fLatestState = state;
 	fChangeCount++;
+
+	locker.Unlock();
+
+	// Send a notification, if this is a system root volume.
+	if (fRoot->IsSystemRoot()) {
+		BMessage message(B_PACKAGE_UPDATE);
+		if (message.AddInt32("event",
+				(int32)B_INSTALLATION_LOCATION_PACKAGES_CHANGED) == B_OK
+			&& message.AddInt32("location", (int32)Location()) == B_OK
+			&& message.AddInt64("change count", fChangeCount) == B_OK) {
+			BRoster::Private().SendTo(&message, NULL, false);
+		}
+	}
 }
 
 

src/servers/registrar/Jamfile

@@ -27,6 +27,7 @@ Server registrar
 	MessageRunnerManager.cpp
 	MessagingService.cpp
 	MIMEManager.cpp
+	PackageWatchingManager.cpp
 	PriorityMessageQueue.cpp
 	RecentApps.cpp
 	RecentEntries.cpp

src/servers/registrar/PackageWatchingManager.cpp

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2014, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "PackageWatchingManager.h"
+
+#include <new>
+
+#include <package/PackageRoster.h>
+
+#include <RegistrarDefs.h>
+
+#include "Debug.h"
+#include "EventMaskWatcher.h"
+
+
+using namespace BPackageKit;
+using namespace BPrivate;
+
+
+PackageWatchingManager::PackageWatchingManager()
+{
+}
+
+
+PackageWatchingManager::~PackageWatchingManager()
+{
+}
+
+
+void
+PackageWatchingManager::HandleStartStopWatching(BMessage* request)
+{
+	status_t error = request->what == B_REG_PACKAGE_START_WATCHING
+		? _AddWatcher(request) : _RemoveWatcher(request);
+
+	if (error == B_OK) {
+		BMessage reply(B_REG_SUCCESS);
+		request->SendReply(&reply);
+	} else {
+		BMessage reply(B_REG_ERROR);
+		reply.AddInt32("error", error);
+		request->SendReply(&reply);
+	}
+}
+
+
+void
+PackageWatchingManager::NotifyWatchers(BMessage* message)
+{
+	int32 event;
+	if (message->FindInt32("event", &event) != B_OK) {
+		WARNING("No event field in notification message\n");
+		return;
+	}
+
+	uint32 eventMask;
+	switch (event) {
+		case B_INSTALLATION_LOCATION_PACKAGES_CHANGED:
+			eventMask = B_WATCH_PACKAGE_INSTALLATION_LOCATIONS;
+			break;
+		default:
+			WARNING("Invalid event: %" B_PRId32 "\n", event);
+			return;
+	}
+
+	EventMaskWatcherFilter filter(eventMask);
+    fWatchingService.NotifyWatchers(message, &filter);
+}
+
+
+status_t
+PackageWatchingManager::_AddWatcher(const BMessage* request)
+{
+	BMessenger target;
+	uint32 eventMask;
+	status_t error;
+	if ((error = request->FindMessenger("target", &target)) != B_OK
+		|| (error = request->FindUInt32("events", &eventMask)) != B_OK) {
+		return error;
+	}
+
+	Watcher* watcher = new(std::nothrow) EventMaskWatcher(target, eventMask);
+	if (watcher == NULL || !fWatchingService.AddWatcher(watcher)) {
+		delete watcher;
+		return B_NO_MEMORY;
+	}
+
+	return B_OK;
+}
+
+
+status_t
+PackageWatchingManager::_RemoveWatcher(const BMessage* request)
+{
+	BMessenger target;
+	status_t error;
+	if ((error = request->FindMessenger("target", &target)) != B_OK)
+		return error;
+
+	if (!fWatchingService.RemoveWatcher(target))
+		return B_BAD_VALUE;
+
+	return B_OK;
+}

src/servers/registrar/PackageWatchingManager.h

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2014, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef PACKAGE_WATCHING_MANAGER_H
+#define PACKAGE_WATCHING_MANAGER_H
+
+
+#include "WatchingService.h"
+
+
+class PackageWatchingManager {
+public:
+								PackageWatchingManager();
+								~PackageWatchingManager();
+
+			void				HandleStartStopWatching(BMessage* request);
+			void				NotifyWatchers(BMessage* message);
+
+private:
+			status_t			_AddWatcher(const BMessage* request);
+			status_t			_RemoveWatcher(const BMessage* request);
+
+private:
+			WatchingService		fWatchingService;
+};
+
+
+#endif	// PACKAGE_WATCHING_MANAGER_H