* The SharedBufferList is now only cloned once in a team, no longer once for

each buffer, and once for each buffer group.
* Also, SharedBufferList::Get() now gets the area to clone from itself, if
  necessary, the caller no longer has to provide it.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@34502 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/media/SharedBufferList.h

@@ -16,7 +16,8 @@ namespace BPrivate {
 class SharedBufferList {
 public:
 	static	area_id				Create(SharedBufferList** _list);
-	static	SharedBufferList*	Get(area_id area);
+	static	SharedBufferList*	Get();
+	static	void				Invalidate();
 
 			void				Put();
 			void 				DeleteGroupAndPut(sem_id groupReclaimSem);

src/kits/media/Buffer.cpp

@@ -201,16 +201,7 @@ BBuffer::BBuffer(const buffer_clone_info& info)
 	if (info.area == 0 && info.buffer == 0)
 		return;
 
-	// ask media_server to get the area_id of the shared buffer list
-	server_get_shared_buffer_area_request areaRequest;
-	server_get_shared_buffer_area_reply areaReply;
-	if (QueryServer(SERVER_GET_SHARED_BUFFER_AREA, &areaRequest,
-			sizeof(areaRequest), &areaReply, sizeof(areaReply)) != B_OK) {
-		ERROR("BBuffer::BBuffer: SERVER_GET_SHARED_BUFFER_AREA failed\n");
-		return;
-	}
-
-	fBufferList = BPrivate::SharedBufferList::Get(areaReply.area);
+	fBufferList = BPrivate::SharedBufferList::Get();
 	if (fBufferList == NULL) {
 		ERROR("BBuffer::BBuffer: _shared_buffer_list::Clone() failed\n");
 		return;

src/kits/media/BufferGroup.cpp

@@ -393,18 +393,7 @@ BBufferGroup::_Init()
 		return fInitError;
 	}
 
-	// ask media_server to get the area_id of the shared buffer list
-	server_get_shared_buffer_area_request areaRequest;
-	server_get_shared_buffer_area_reply areaReply;
-	if (QueryServer(SERVER_GET_SHARED_BUFFER_AREA, &areaRequest,
-			sizeof(areaRequest), &areaReply, sizeof(areaReply)) != B_OK) {
-		ERROR("BBufferGroup::InitBufferGroup: SERVER_GET_SHARED_BUFFER_AREA "
-			"failed\n");
-		fInitError = B_ERROR;
-		return fInitError;
-	}
-
-	fBufferList = BPrivate::SharedBufferList::Get(areaReply.area);
+	fBufferList = BPrivate::SharedBufferList::Get();
 	if (fBufferList == NULL) {
 		ERROR("BBufferGroup::InitBufferGroup: SharedBufferList::Get() "
 			"failed\n");

src/kits/media/MediaRoster.cpp

@@ -57,16 +57,19 @@ char __dont_remove_copyright_from_binary[] = "Copyright (c) 2002-2006 Marcus "
 
 #include <AppMisc.h>
 
-#include "debug.h"
-#include "MediaRosterEx.h"
-#include "MediaMisc.h"
-#include "PortPool.h"
-#include "ServerInterface.h"
-#include "DataExchange.h"
-#include "DormantNodeManager.h"
-#include "Notifications.h"
+#include <debug.h>
+#include <DataExchange.h>
+#include <DormantNodeManager.h>
+#include <MediaRosterEx.h>
+#include <MediaMisc.h>
+#include <Notifications.h>
+#include <PortPool.h>
+#include <ServerInterface.h>
+#include <SharedBufferList.h>
+
 #include "TimeSourceObjectManager.h"
 
+
 namespace BPrivate { namespace media {
 
 // the BMediaRoster destructor is private,
@@ -3206,6 +3209,8 @@ BMediaRoster::~BMediaRoster()
 	QueryServer(SERVER_UNREGISTER_APP, &request, sizeof(request), &reply,
 		sizeof(reply));
 
+	BPrivate::SharedBufferList::Invalidate();
+
 	// Unset the global instance pointer, the destructor is also called
 	// if a client app calls Lock(); and Quit(); directly.
 	sDefaultInstance = NULL;
@@ -3238,7 +3243,8 @@ status_t BMediaRoster::_Reserved_MediaRoster_7(void *) { return B_ERROR; }
 
 
 BMediaRoster::BMediaRoster()
-	: BLooper("_BMediaRoster_", B_URGENT_DISPLAY_PRIORITY,
+	:
+	BLooper("_BMediaRoster_", B_URGENT_DISPLAY_PRIORITY,
 		B_LOOPER_PORT_DEFAULT_CAPACITY)
 {
 	CALLED();

src/kits/media/SharedBufferList.cpp

@@ -17,9 +17,18 @@
 
 #include <string.h>
 
+#include <Autolock.h>
 #include <Buffer.h>
+#include <Locker.h>
 
-#include "debug.h"
+#include <debug.h>
+#include <DataExchange.h>
+
+
+static BPrivate::SharedBufferList* sList;
+static area_id sArea;
+static int32 sRefCount;
+static BLocker sLocker("shared buffer list");
 
 
 namespace BPrivate {
@@ -50,21 +59,41 @@ SharedBufferList::Create(SharedBufferList** _list)
 
 
 /*static*/ SharedBufferList*
-SharedBufferList::Get(area_id id)
+SharedBufferList::Get()
 {
 	CALLED();
-	// TODO: map this only once per team!
 
-	SharedBufferList* list;
-	area_id area = clone_area("shared buffer list clone", (void**)&list,
-		B_ANY_ADDRESS, B_READ_AREA | B_WRITE_AREA, id);
-	if (area < 0) {
-		ERROR("SharedBufferList::Clone() clone area: %ld err = %s\n", id,
-			strerror(area));
+	BAutolock _(sLocker);
+
+	if (atomic_add(&sRefCount, 1) > 0 && sList != NULL)
+		return sList;
+
+	// ask media_server to get the area_id of the shared buffer list
+	server_get_shared_buffer_area_request areaRequest;
+	server_get_shared_buffer_area_reply areaReply;
+	if (QueryServer(SERVER_GET_SHARED_BUFFER_AREA, &areaRequest,
+			sizeof(areaRequest), &areaReply, sizeof(areaReply)) != B_OK) {
+		ERROR("SharedBufferList::Get() SERVER_GET_SHARED_BUFFER_AREA failed\n");
 		return NULL;
 	}
 
-	return list;
+	sArea = clone_area("shared buffer list clone", (void**)&sList,
+		B_ANY_ADDRESS, B_READ_AREA | B_WRITE_AREA, areaReply.area);
+	if (sArea < 0) {
+		ERROR("SharedBufferList::Get() clone area %ld: %s\n",
+			areaReply.area, strerror(sArea));
+		return NULL;
+	}
+
+	return sList;
+}
+
+
+/*static*/ void
+SharedBufferList::Invalidate()
+{
+	delete_area(sArea);
+	sList = NULL;
 }
 
 
@@ -72,10 +101,10 @@ void
 SharedBufferList::Put()
 {
 	CALLED();
+	BAutolock _(sLocker);
 
-	area_id area = area_for(this);
-	if (area >= 0)
-		delete_area(area);
+	if (atomic_add(&sRefCount, -1) == 1)
+		Invalidate();
 }