From f748e2d460fd3b179aecd7092fb46ec5daf450f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Axel=20D=C3=B6rfler?= <axeld@pinc-software.de>
Date: Thu, 12 Feb 2004 03:00:56 +0000
Subject: [PATCH] Extended watching mechanism (it now works more like the
 BHandler watching mechanism) - it's not really used yet, though. Fixed some
 variable initialization bugs and missing return values.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@6566 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 src/apps/diskprobe/DataEditor.cpp | 81 +++++++++++++++++++++++++++++--
 src/apps/diskprobe/DataEditor.h   | 13 +++++
 2 files changed, 90 insertions(+), 4 deletions(-)

diff --git a/src/apps/diskprobe/DataEditor.cpp b/src/apps/diskprobe/DataEditor.cpp
index 5a38ec8fbf..a6b748ce7f 100644
--- a/src/apps/diskprobe/DataEditor.cpp
+++ b/src/apps/diskprobe/DataEditor.cpp
@@ -9,6 +9,8 @@
 #include <Autolock.h>
 #include <NodeMonitor.h>
 
+#include <string.h>
+
 
 class DataChange {
 	public:
@@ -170,7 +172,7 @@ status_t
 DataEditor::SetTo(const char *path, const char *attribute)
 {
 	BEntry entry(path);
-	SetTo(entry, attribute);
+	return SetTo(entry, attribute);
 }
 
 
@@ -178,7 +180,7 @@ status_t
 DataEditor::SetTo(entry_ref &ref, const char *attribute)
 {
 	BEntry entry(&ref);
-	SetTo(entry, attribute);
+	return SetTo(entry, attribute);
 }
 
 
@@ -195,18 +197,32 @@ DataEditor::SetTo(BEntry &entry, const char *attribute)
 		fIsReadOnly = true;
 	}
 
+	struct stat stat;
+	stat.st_mode = 0;
+
+	fFile.GetStat(&stat);
+	fIsDevice = (stat.st_mode & (S_IFBLK | S_IFCHR)) != 0;
+
+	// ToDo: add support for devices and attributes!
 	status = fFile.GetSize(&fSize);
 	if (status < B_OK) {
 		fFile.Unset();
 		return status;
 	}
 
+	if (attribute != NULL)
+		fAttribute = strdup(attribute);
+	else
+		fAttribute = NULL;
+
+	fView = NULL;
 	fBlockSize = 512;
-	fAttribute = attribute;
-	fRealViewOffset = -1;
+	fRealViewOffset = 0;
 	fViewOffset = 0;
 	fRealViewSize = fViewSize = fBlockSize;
 	fNeedsUpdate = true;
+
+	return B_OK;
 }
 
 
@@ -384,6 +400,7 @@ status_t
 DataEditor::SetFileSize(off_t size)
 {
 	fSize = size;
+	return B_OK;
 }
 
 
@@ -399,6 +416,8 @@ DataEditor::SetViewOffset(off_t offset)
 	fRealViewOffset = (offset / fBlockSize) * fBlockSize;
 	fViewOffset = offset;
 	fNeedsUpdate = true;
+
+	return B_OK;
 }
 
 
@@ -483,21 +502,75 @@ DataEditor::Unlock()
 }
 
 
+void 
+DataEditor::SendNotices(uint32 what, BMessage *message)
+{
+	if (fObservers.CountItems() == 0)
+		return;
+
+	BMessage *notice;
+	if (message) {
+		notice = new BMessage(*message);
+		notice->what = B_OBSERVER_NOTICE_CHANGE;
+		notice->AddInt32(B_OBSERVE_ORIGINAL_WHAT, message->what);
+	} else
+		notice = new BMessage(B_OBSERVER_NOTICE_CHANGE);
+
+	notice->AddInt32(B_OBSERVE_WHAT_CHANGE, what);
+
+	for (int32 i = fObservers.CountItems(); i-- > 0;) {
+		BMessenger *messenger = fObservers.ItemAt(i);
+		messenger->SendMessage(notice);
+	}
+
+	delete notice;
+}
+
+
 status_t 
 DataEditor::StartWatching(BMessenger target)
 {
+	BAutolock locker(fLock);
+
 	node_ref node;
 	status_t status = fFile.GetNodeRef(&node);
 	if (status < B_OK)
 		return status;
 
+	fObservers.AddItem(new BMessenger(target));
+
 	return watch_node(&node, B_WATCH_STAT | B_WATCH_ATTR, target);
 }
 
 
+status_t
+DataEditor::StartWatching(BHandler *handler, BLooper *looper)
+{
+	return StartWatching(BMessenger(handler, looper));
+}
+
+
 void 
 DataEditor::StopWatching(BMessenger target)
 {
+	BAutolock locker(fLock);
+
+	for (int32 i = fObservers.CountItems(); i-- > 0;) {
+		BMessenger *messenger = fObservers.ItemAt(i);
+		if (*messenger == target) {
+			fObservers.RemoveItemAt(i);
+			delete messenger;
+			break;
+		}
+	}
+
 	stop_watching(target);
 }
 
+
+void 
+DataEditor::StopWatching(BHandler *handler, BLooper *looper)
+{
+	StopWatching(BMessenger(handler, looper));
+}
+
diff --git a/src/apps/diskprobe/DataEditor.h b/src/apps/diskprobe/DataEditor.h
index 13021d9ab9..e84968bcd9 100644
--- a/src/apps/diskprobe/DataEditor.h
+++ b/src/apps/diskprobe/DataEditor.h
@@ -29,8 +29,11 @@ class DataEditor {
 
 		bool IsReadOnly() const { return fIsReadOnly; }
 		bool IsDevice() const { return fIsDevice; }
+		bool IsAttribute() const { return fAttribute != NULL; }
 		//bool IsModified() const { return fIsModified; }
 
+		const char *Attribute() const { return fAttribute; }
+
 		status_t InitCheck();
 
 		status_t Replace(off_t offset, const uint8 *data, size_t length);
@@ -65,16 +68,21 @@ class DataEditor {
 		void Unlock();
 
 		status_t StartWatching(BMessenger target);
+		status_t StartWatching(BHandler *handler, BLooper *looper = NULL);
 		void StopWatching(BMessenger target);
+		void StopWatching(BHandler *handler, BLooper *looper = NULL);
 
 		BFile &File() { return fFile; }
 
 	private:
+		void SendNotices(uint32 what, BMessage *message = NULL);
 		status_t Update();
 		void AddChange(DataChange *change);
 		void ApplyChanges();
 		void RemoveRedos();
 
+		BObjectList<BMessenger> fObservers;
+
 		BFile		fFile;
 		const char	*fAttribute;
 		bool		fIsDevice, fIsReadOnly;
@@ -93,4 +101,9 @@ class DataEditor {
 		size_t		fBlockSize;
 };
 
+static const uint32 kMsgDataEditorUndoState = 'deUS';
+static const uint32 kMsgDataEditorRedoState = 'deRS';
+static const uint32 kMsgDataEditorModifiedState = 'deMS';
+static const uint32 kMsgDataEditorUpdate = 'deUp';
+
 #endif	/* DATA_EDITOR_H */