internal unsafe ListEntryHandler(NtfsAttributeType searchedAttributeType, AttributeNameFilterDelegate nameFilter, RecordAttributeEnumeratorCallbackDelegate callback) { _callback = callback ?? throw new ArgumentNullException(); _dataRetrievalCallback = HandleData; _searchedAttributeType = searchedAttributeType; _nameFilter = nameFilter; }
internal unsafe void EnumerateRecordAttributes(NtfsPartition owner, ulong recordLBA, ref byte *buffer, RecordAttributeEnumeratorCallbackDelegate callback, NtfsAttributeType searchedType = NtfsAttributeType.Any, AttributeNameFilterDelegate nameFilter = null) { using (IPartitionClusterData data = owner.ReadSectors(recordLBA)) { buffer = data.Data; NtfsFileRecord *header = (NtfsFileRecord *)buffer; header->AssertRecordType(); if (1024 < header->BytesAllocated) { throw new NotImplementedException(); } EnumerateRecordAttributes(header, callback, searchedType, nameFilter); } }
/// <summary>Retrieve the Nth attribute of a given kind from a file record.</summary> /// <param name="kind">Searched attribute type.</param> /// <param name="dataStream">On return this parameter value is a null reference most of /// the time. Otherwise for attributes that are retrieved from an /// <see cref="NtfsAttributeListAttribute"/> instance, this is a stream that support /// attribute data content reading.</param> /// <param name="order">Attribute rank. Default is first. This is usefull for some kind of /// attributes such as Data one that can appear several times in a record.</param> /// <param name="nameFilter">An optional name filter delegate that will sort out those /// attributes we want to retrieve based on their name.</param> /// <returns>The retrieved attribute or a null reference if not found.</returns> internal unsafe NtfsAttribute *GetAttribute(NtfsAttributeType kind, out Stream dataStream, uint order = 1, AttributeNameFilterDelegate nameFilter = null) { NtfsAttribute *result = null; Stream retrievedDataStream = null; EnumerateRecordAttributes(delegate(NtfsAttribute * found, Stream attributeDataStream) { if (kind == found->AttributeType) { if (0 == --order) { result = found; retrievedDataStream = attributeDataStream; return(false); } } return(true); }, kind, nameFilter); dataStream = retrievedDataStream; return(result); }
/// <summary>Enumerate attributes bound to this <see cref="NtfsFileRecord"/>, optionally filtering /// on attribute name.</summary> /// <param name="header">The file record.</param> /// <param name="callback"></param> /// <param name="searchedAttributeType"></param> /// <param name="nameFilter">An optional name filter that will be provided with the basic attribute /// properties (including name) in order to decide if data should be retrieved. This is especially /// usefull for <see cref="NtfsAttributeListAttribute"/> attributes that may reference lengthy /// attributes data which are expensive to retrieve.</param> internal static unsafe void EnumerateRecordAttributes(NtfsFileRecord *header, RecordAttributeEnumeratorCallbackDelegate callback, NtfsAttributeType searchedAttributeType, AttributeNameFilterDelegate nameFilter) { // Walk attributes, seeking for the searched one. NtfsAttribute *currentAttribute = (NtfsAttribute *)((byte *)header + header->AttributesOffset); NtfsAttributeListAttribute *pendingAttributeList = null; NtfsAttribute *[] candidates = new NtfsAttribute *[MaxAttributeCount]; int candidatesCount = 0; for (int attributeIndex = 0; attributeIndex < header->NextAttributeNumber; attributeIndex++) { if (currentAttribute->IsLast) { break; } if (header->BytesInUse < ((byte *)currentAttribute - (byte *)header)) { break; } if (NtfsAttributeType.EndOfListMarker == currentAttribute->AttributeType) { break; } // If we found an AttributeListAttribute, we must go one level deeper to // complete the enumeration. if (NtfsAttributeType.AttributeAttributeList == currentAttribute->AttributeType) { if (null != pendingAttributeList) { // No more than one attribute of this kind per file record. throw new ApplicationException(); } if (NtfsAttributeType.AttributeAttributeList == searchedAttributeType) { if (!callback(currentAttribute, null)) { return; } } // Defer handling pendingAttributeList = (NtfsAttributeListAttribute *)currentAttribute; break; } if (candidatesCount >= MaxAttributeCount) { throw new ApplicationException(); } if ((NtfsAttributeType.Any == searchedAttributeType) || (currentAttribute->AttributeType == searchedAttributeType)) { candidates[candidatesCount++] = currentAttribute; } currentAttribute = (NtfsAttribute *)((byte *)currentAttribute + currentAttribute->Length); } if (NtfsAttributeType.AttributeAttributeList == searchedAttributeType) { // Either we already found one such attribute and invoked the callback or found none and // we can return immediately. Should we have found several such attributes we would have // risen an exception. return; } if (null == pendingAttributeList) { // We already walked every attributes and captured those that matched the type filter if // any. Invoke callbak on each such attribute. for (int candidateIndex = 0; candidateIndex < candidatesCount; candidateIndex++) { if (!callback(candidates[candidateIndex], null)) { return; } } // We are done. return; } NtfsAttributeListAttribute.Dump(pendingAttributeList); // HandleAttributeListAttributeEntry // We have an attribute list attribute. Delegate him the enumeration. NtfsPartition currentPartition = NtfsPartition.Current; NtfsAttributeListAttribute.EnumerateEntries((NtfsAttribute *)pendingAttributeList, searchedAttributeType, new ListEntryHandler(searchedAttributeType, nameFilter, callback).HandleListEntry); return; }
internal unsafe void EnumerateRecordAttributes(RecordAttributeEnumeratorCallbackDelegate callback, NtfsAttributeType searchedType = NtfsAttributeType.Any, AttributeNameFilterDelegate nameFilter = null) { fixed(NtfsFileRecord *header = &this) { EnumerateRecordAttributes(header, callback, searchedType, nameFilter); } }