Improve exception handling on backup store side.

Add a new exception code to represent an object being completely missing (not
found on the store at all), separate from not being found in a particular
directory.

Improve mapping of server-side exceptions to protocol error messages returned
to the client.

Add handling for missing exceptions, such as
BackupStoreException::PatchChainInfoBadInDirectory, and the new
BackupStoreException::ObjectDoesNotExist.

Fix mapping for BackupStoreException::CouldNotFindEntryInDirectory to make it
distinguistable from BackupStoreException::ObjectDoesNotExist.

2 files changed, 32 insertions, 2 deletions

diff --git a/lib/backupstore/BackupCommands.cpp b/lib/backupstore/BackupCommands.cpp
index ab0dc4b8..22ef0215 100644
--- a/lib/backupstore/BackupCommands.cpp
+++ b/lib/backupstore/BackupCommands.cpp
@@ -85,12 +85,20 @@ std::auto_ptr<BackupProtocolMessage> BackupProtocolReplyable::HandleException(Bo
 		}
 		else if(e.GetSubType() == BackupStoreException::CouldNotFindEntryInDirectory)
 		{
-			return PROTOCOL_ERROR(Err_DoesNotExist);
+			return PROTOCOL_ERROR(Err_DoesNotExistInDirectory);
 		}
 		else if(e.GetSubType() == BackupStoreException::NameAlreadyExistsInDirectory)
 		{
 			return PROTOCOL_ERROR(Err_TargetNameExists);
 		}
+		else if(e.GetSubType() == BackupStoreException::ObjectDoesNotExist)
+		{
+			return PROTOCOL_ERROR(Err_DoesNotExist);
+		}
+		else if(e.GetSubType() == BackupStoreException::PatchChainInfoBadInDirectory)
+		{
+			return PROTOCOL_ERROR(Err_PatchConsistencyError);
+		}
 	}
 
 	throw;
@@ -779,7 +787,28 @@ std::auto_ptr<BackupProtocolMessage> BackupProtocolGetObjectName::DoCommand(Back
 		}
 
 		// Load up the directory
-		const BackupStoreDirectory &rdir(rContext.GetDirectory(dirID));
+		const BackupStoreDirectory *pDir;
+
+		try
+		{
+			pDir = &rContext.GetDirectory(dirID);
+		}
+		catch(BackupStoreException &e)
+		{
+			if(e.GetSubType() == BackupStoreException::ObjectDoesNotExist)
+			{
+				// If this can't be found, then there is a problem...
+				// tell the caller it can't be found.
+				return std::auto_ptr<BackupProtocolMessage>(
+					new BackupProtocolObjectName(
+						BackupProtocolObjectName::NumNameElements_ObjectDoesntExist,
+						0, 0, 0));
+			}
+
+			throw;
+		}
+
+		const BackupStoreDirectory& rdir(*pDir);
 
 		// Find the element in this directory and store it's name
 		if(objectID != ObjectID_DirectoryOnly)
diff --git a/lib/backupstore/BackupStoreException.txt b/lib/backupstore/BackupStoreException.txt
index b49a9cf2..40232a8e 100644
--- a/lib/backupstore/BackupStoreException.txt
+++ b/lib/backupstore/BackupStoreException.txt
@@ -72,3 +72,4 @@ UnknownObjectRefCountRequested	68	A reference count was requested for an object
 MultiplyReferencedObject	69	Attempted to modify an object with multiple references, should be uncloned first
 CorruptReferenceCountDatabase	70	The account's refcount database is corrupt and must be rebuilt by housekeeping.
 CancelledByBackgroundTask	71	The current task was cancelled on request by the background task.
+ObjectDoesNotExist		72	The specified object ID does not exist in the store.