[ros-diffs] [tthompson] 71660: [NTFS] When writing to a file, increase the file size if trying to write past the end. *FindAttribute() has been given an optional pointer to a ULONG that will receive the offset...

Author: tthompson
Date: Wed Jun 22 21:20:50 2016
New Revision: 71660

URL: http://svn.reactos.org/svn/reactos?rev=71660&view=rev
Log:
[NTFS]
When writing to a file, increase the file size if trying to write past the end.
*FindAttribute() has been given an optional pointer to a ULONG that will receive the
offset of the found attribute from the beginning of the record. This is to allow for found
attributes to be written back into their file records.
+SetAttributeDataLength()
+UpdateFileRecord() - Updates a file record in the master file table at a given index.
+AddFixupArray() - Prepares a file record or directory index for writing to the disk.

Modified:
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/attrib.c
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/dirctl.c
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fcb.c
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fsctl.c
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/mft.c
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/ntfs.h
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/rw.c
    branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/volinfo.c

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/attrib.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/attrib.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/attrib.c	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -150,6 +150,8 @@
 PNTFS_ATTR_RECORD
 InternalGetNextAttribute(PFIND_ATTR_CONTXT Context)
 {
+    PNTFS_ATTR_RECORD NextAttribute;
+
     if (Context->CurrAttr == (PVOID)-1)
     {
         return NULL;
@@ -165,7 +167,10 @@
             return NULL;
         }
 
-        Context->CurrAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)Context->CurrAttr +
Context->CurrAttr->Length);
+        NextAttribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Context->CurrAttr +
Context->CurrAttr->Length);
+        Context->Offset += ((ULONG_PTR)NextAttribute -
(ULONG_PTR)Context->CurrAttr);
+        Context->CurrAttr = NextAttribute;
+
         if (Context->CurrAttr < Context->LastAttr &&
             Context->CurrAttr->Type != AttributeEnd)
         {
@@ -186,7 +191,9 @@
     }
     else if (Context->CurrAttr->Length != 0)
     {
-        Context->CurrAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)Context->CurrAttr +
Context->CurrAttr->Length);
+        NextAttribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Context->CurrAttr +
Context->CurrAttr->Length);
+        Context->Offset += ((ULONG_PTR)NextAttribute -
(ULONG_PTR)Context->CurrAttr);
+        Context->CurrAttr = NextAttribute;
     }
     else
     {
@@ -223,6 +230,7 @@
     Context->LastAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse);
     Context->NonResidentStart = NULL;
     Context->NonResidentEnd = NULL;
+    Context->Offset = FileRecord->AttributeOffset;
 
     if (Context->FirstAttr->Type == AttributeEnd)
     {
@@ -246,6 +254,7 @@
     else
     {
         *Attribute = Context->CurrAttr;
+        Context->Offset = (UCHAR*)Context->CurrAttr - (UCHAR*)FileRecord;
     }
 
     return STATUS_SUCCESS;
@@ -307,7 +316,8 @@
 
     FileNameAttr = (PFILENAME_ATTRIBUTE)((ULONG_PTR)Attribute +
Attribute->Resident.ValueOffset);
     DbgPrint(" (%x) '%.*S' ", FileNameAttr->NameType,
FileNameAttr->NameLength, FileNameAttr->Name);
-    DbgPrint(" '%x' ", FileNameAttr->FileAttributes);
+    DbgPrint(" '%x' \n", FileNameAttr->FileAttributes);
+    DbgPrint(" AllocatedSize: %I64u\nDataSize: %I64u\n",
FileNameAttr->AllocatedSize, FileNameAttr->DataSize);
 }
 
 
@@ -481,8 +491,8 @@
         {
             FindRun(Attribute,0,&lcn, &runcount);
 
-            DbgPrint("  AllocatedSize %I64u  DataSize %I64u\n",
-                     Attribute->NonResident.AllocatedSize,
Attribute->NonResident.DataSize);
+            DbgPrint("  AllocatedSize %I64u  DataSize %I64u InitilizedSize
%I64u\n",
+                     Attribute->NonResident.AllocatedSize,
Attribute->NonResident.DataSize, Attribute->NonResident.InitializedSize);
             DbgPrint("  logical clusters: %I64u - %I64u\n",
                      lcn, lcn + runcount - 1);
         }

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/dirctl.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/dirctl.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/dirctl.c	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -47,7 +47,7 @@
     NTSTATUS Status;
     PNTFS_ATTR_CONTEXT DataContext;
 
-    Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Stream, StreamLength,
&DataContext);
+    Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Stream, StreamLength,
&DataContext, NULL);
     if (NT_SUCCESS(Status))
     {
         Size = AttributeDataLength(&DataContext->Record);

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fcb.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fcb.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fcb.c	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -568,7 +568,7 @@
     }
     else if (Colon != 0)
     {
-        Status = FindAttribute(Vcb, FileRecord, AttributeData, Colon, wcslen(Colon),
&DataContext);
+        Status = FindAttribute(Vcb, FileRecord, AttributeData, Colon, wcslen(Colon),
&DataContext, NULL);
         if (!NT_SUCCESS(Status))
         {
             return STATUS_OBJECT_NAME_NOT_FOUND;
@@ -741,7 +741,7 @@
         return Status;
     }
 
-    Status = FindAttribute(Vcb, FileRecord, Type, Name, NameLength, &AttrCtxt);
+    Status = FindAttribute(Vcb, FileRecord, Type, Name, NameLength, &AttrCtxt,
NULL);
     if (!NT_SUCCESS(Status))
     {
         ExFreePoolWithTag(FileRecord, TAG_NTFS);

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fsctl.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fsctl.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/fsctl.c	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -295,7 +295,7 @@
         return Status;
     }
 
-    Status = FindAttribute(DeviceExt, DeviceExt->MasterFileTable, AttributeData,
L"", 0, &DeviceExt->MFTContext);
+    Status = FindAttribute(DeviceExt, DeviceExt->MasterFileTable, AttributeData,
L"", 0, &DeviceExt->MFTContext, NULL);
     if (!NT_SUCCESS(Status))
     {
         DPRINT1("Can't find data attribute for Master File Table.\n");
@@ -333,7 +333,7 @@
     NtfsDumpFileAttributes(DeviceExt, VolumeRecord);
 
     /* Get volume name */
-    Status = FindAttribute(DeviceExt, VolumeRecord, AttributeVolumeName, L"",
0, &AttrCtxt);
+    Status = FindAttribute(DeviceExt, VolumeRecord, AttributeVolumeName, L"",
0, &AttrCtxt, NULL);
 
     if (NT_SUCCESS(Status) && AttrCtxt->Record.Resident.ValueLength != 0)
     {
@@ -374,7 +374,7 @@
     DeviceExt->VolumeFcb = VolumeFcb;
 
     /* Get volume information */
-    Status = FindAttribute(DeviceExt, VolumeRecord, AttributeVolumeInformation,
L"", 0, &AttrCtxt);
+    Status = FindAttribute(DeviceExt, VolumeRecord, AttributeVolumeInformation,
L"", 0, &AttrCtxt, NULL);
 
     if (NT_SUCCESS(Status) && AttrCtxt->Record.Resident.ValueLength != 0)
     {
@@ -804,7 +804,7 @@
         return Status;
     }
 
-    Status = FindAttribute(DeviceExt, BitmapRecord, AttributeData, L"", 0,
&DataContext);
+    Status = FindAttribute(DeviceExt, BitmapRecord, AttributeData, L"", 0,
&DataContext, NULL);
     if (!NT_SUCCESS(Status))
     {
         DPRINT1("Failed find $DATA for bitmap: %lx\n", Status);

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/mft.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/mft.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/mft.c	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -81,13 +81,24 @@
 }
 
 
+/**
+* @name FindAttribute
+* @implemented
+* 
+* Searches a file record for an attribute matching the given type and name.
+*
+* @param Offset
+* Optional pointer to a ULONG that will receive the offset of the found attribute
+* from the beginning of the record. Can be set to NULL.
+*/
 NTSTATUS
 FindAttribute(PDEVICE_EXTENSION Vcb,
               PFILE_RECORD_HEADER MftRecord,
               ULONG Type,
               PCWSTR Name,
               ULONG NameLength,
-              PNTFS_ATTR_CONTEXT * AttrCtx)
+              PNTFS_ATTR_CONTEXT * AttrCtx,
+              PULONG Offset)
 {
     BOOLEAN Found;
     NTSTATUS Status;
@@ -123,6 +134,10 @@
                 /* Found it, fill up the context and return. */
                 DPRINT("Found context\n");
                 *AttrCtx = PrepareAttributeContext(Attribute);
+
+                if (Offset != NULL)
+                    *Offset = Context.Offset;
+
                 FindCloseAttribute(&Context);
                 return STATUS_SUCCESS;
             }
@@ -155,6 +170,61 @@
         return AttrRecord->Resident.ValueLength;
 }
 
+
+NTSTATUS
+SetAttributeDataLength(PFILE_OBJECT FileObject,
+                       PNTFS_FCB Fcb,
+                       PNTFS_ATTR_CONTEXT AttrContext,
+                       ULONG AttrOffset,
+                       PFILE_RECORD_HEADER FileRecord,
+                       PDEVICE_EXTENSION DeviceExt,
+                       PLARGE_INTEGER DataSize)
+{
+    if (AttrContext->Record.IsNonResident)
+    {
+        // do we need to increase the allocation size?
+        if (AttrContext->Record.NonResident.AllocatedSize < DataSize->QuadPart)
+        {            
+            DPRINT1("FixMe: Increasing allocation size is unimplemented!\n");
+            return STATUS_NOT_IMPLEMENTED;
+        }
+
+        // TODO: is the file compressed, encrypted, or sparse?
+
+        // NOTE: we need to have acquired the main resource exclusively, as well as(?)
the PagingIoResource
+
+        // TODO: update the allocated size on-disk
+        DPRINT("Allocated Size: %I64u\n",
AttrContext->Record.NonResident.AllocatedSize);
+
+        AttrContext->Record.NonResident.DataSize = DataSize->QuadPart;
+        AttrContext->Record.NonResident.InitializedSize = DataSize->QuadPart;
+
+        Fcb->RFCB.FileSize = *DataSize;
+        Fcb->RFCB.ValidDataLength = *DataSize;
+
+        DPRINT("Data Size: %I64u\n", Fcb->RFCB.FileSize.QuadPart);
+
+        //NtfsDumpFileAttributes(Fcb->Vcb, FileRecord);
+
+        // copy the attribute back into the FileRecord
+        RtlCopyMemory((PCHAR)FileRecord + AttrOffset, &AttrContext->Record,
AttrContext->Record.Length);
+
+        //NtfsDumpFileAttributes(Fcb->Vcb, FileRecord);
+
+        // write the updated file record back to disk
+        UpdateFileRecord(Fcb->Vcb, Fcb->MFTIndex, FileRecord);
+
+        CcSetFileSizes(FileObject, (PCC_FILE_SIZES)&Fcb->RFCB.AllocationSize);
+    }
+    else
+    {
+        // we can't yet handle resident attributes
+        DPRINT1("FixMe: Can't handle increasing length of resident
attribute\n");
+        return STATUS_NOT_IMPLEMENTED;
+    }
+
+    return STATUS_SUCCESS;
+}
 
 ULONG
 ReadAttribute(PDEVICE_EXTENSION Vcb,
@@ -615,8 +685,39 @@
     return FixupUpdateSequenceArray(Vcb, &file->Ntfs);
 }
 
-
-NTSTATUS 
+/**
+* UpdateFileRecord
+* @implemented
+* Writes a file record to the master file table, at a given index.
+*/
+NTSTATUS
+UpdateFileRecord(PDEVICE_EXTENSION Vcb,
+                 ULONGLONG index,
+                 PFILE_RECORD_HEADER file)
+{
+    ULONG BytesWritten;
+    NTSTATUS Status = STATUS_SUCCESS;
+
+    DPRINT("UpdateFileRecord(%p, %I64x, %p)\n", Vcb, index, file);
+
+    // Add the fixup array to prepare the data for writing to disk
+    AddFixupArray(Vcb, file);
+
+    // write the file record to the master file table
+    Status = WriteAttribute(Vcb, Vcb->MFTContext, index *
Vcb->NtfsInfo.BytesPerFileRecord, (const PUCHAR)file,
Vcb->NtfsInfo.BytesPerFileRecord, &BytesWritten);
+
+    // TODO: Update MFT mirror
+
+    if (!NT_SUCCESS(Status))
+    {
+        DPRINT1("UpdateFileRecord failed: %I64u written, %u expected\n",
BytesWritten, Vcb->NtfsInfo.BytesPerFileRecord);
+    }
+
+    return Status;
+}
+
+
+NTSTATUS
 FixupUpdateSequenceArray(PDEVICE_EXTENSION Vcb,
                          PNTFS_RECORD_HEADER Record)
 {
@@ -630,6 +731,8 @@
     USACount = Record->UsaCount - 1; /* Exclude the USA Number. */
     Block = (USHORT*)((PCHAR)Record + Vcb->NtfsInfo.BytesPerSector - 2);
 
+    DPRINT("FixupUpdateSequenceArray(%p, %p)\nUSANumber: %u\tUSACount: %u\n",
Vcb, Record, USANumber, USACount);
+
     while (USACount)
     {
         if (*Block != USANumber)
@@ -645,6 +748,36 @@
     return STATUS_SUCCESS;
 }
 
+NTSTATUS
+AddFixupArray(PDEVICE_EXTENSION Vcb,
+              PFILE_RECORD_HEADER Record)
+{
+    USHORT *pShortToFixUp;
+    unsigned int ArrayEntryCount = Record->BytesAllocated /
Vcb->NtfsInfo.BytesPerSector;
+    unsigned int Offset = Vcb->NtfsInfo.BytesPerSector - 2;
+    int i;
+
+    PFIXUP_ARRAY fixupArray = (PFIXUP_ARRAY)((UCHAR*)Record +
Record->Ntfs.UsaOffset);
+
+    DPRINT("AddFixupArray(%p, %p)\n fixupArray->USN: %u, ArrayEntryCount:
%u\n", Vcb, Record, fixupArray->USN, ArrayEntryCount);
+
+    if (Record->BytesAllocated % Vcb->NtfsInfo.BytesPerSector != 0)
+        ArrayEntryCount++;
+
+    fixupArray->USN++;
+
+    for (i = 0; i < ArrayEntryCount; i++)
+    {
+        DPRINT("USN: %u\tOffset: %u\n", fixupArray->USN, Offset);
+
+        pShortToFixUp = (USHORT*)((UCHAR*)Record + Offset);
+        fixupArray->Array[i] = *pShortToFixUp;
+        *pShortToFixUp = fixupArray->USN;
+        Offset += Vcb->NtfsInfo.BytesPerSector;
+    }
+
+    return STATUS_SUCCESS;
+}
 
 NTSTATUS
 ReadLCN(PDEVICE_EXTENSION Vcb,
@@ -783,7 +916,7 @@
         return STATUS_OBJECT_PATH_NOT_FOUND; 
     }
 
-    Status = FindAttribute(Vcb, MftRecord, AttributeIndexAllocation, L"$I30",
4, &IndexAllocationCtx);
+    Status = FindAttribute(Vcb, MftRecord, AttributeIndexAllocation, L"$I30",
4, &IndexAllocationCtx, NULL);
     if (!NT_SUCCESS(Status))
     {
         DPRINT("Corrupted filesystem!\n");
@@ -853,7 +986,7 @@
     }
 
     ASSERT(MftRecord->Ntfs.Type == NRH_FILE_TYPE);
-    Status = FindAttribute(Vcb, MftRecord, AttributeIndexRoot, L"$I30", 4,
&IndexRootCtx);
+    Status = FindAttribute(Vcb, MftRecord, AttributeIndexRoot, L"$I30", 4,
&IndexRootCtx, NULL);
     if (!NT_SUCCESS(Status))
     {
         ExFreePoolWithTag(MftRecord, TAG_NTFS);

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/ntfs.h
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/ntfs.h	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/ntfs.h	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -483,7 +483,14 @@
     PNTFS_ATTR_RECORD LastAttr;
     PNTFS_ATTR_RECORD NonResidentStart;
     PNTFS_ATTR_RECORD NonResidentEnd;
+    ULONG Offset;
 } FIND_ATTR_CONTXT, *PFIND_ATTR_CONTXT;
+
+typedef struct
+{
+    USHORT USN;
+    USHORT Array[];
+} FIXUP_ARRAY, *PFIXUP_ARRAY;
 
 extern PNTFS_GLOBAL_DATA NtfsGlobalData;
 
@@ -555,7 +562,7 @@
               IN LONGLONG StartingOffset,
               IN ULONG Length,
               IN ULONG SectorSize,
-              IN PUCHAR Buffer);
+              IN const PUCHAR Buffer);
 
 NTSTATUS
 NtfsReadSectors(IN PDEVICE_OBJECT DeviceObject,
@@ -759,6 +766,15 @@
 ULONGLONG
 AttributeDataLength(PNTFS_ATTR_RECORD AttrRecord);
 
+NTSTATUS
+SetAttributeDataLength(PFILE_OBJECT FileObject,
+                       PNTFS_FCB Fcb,
+                       PNTFS_ATTR_CONTEXT AttrContext,
+                       ULONG AttrOffset,
+                       PFILE_RECORD_HEADER FileRecord,
+                       PDEVICE_EXTENSION DeviceExt,
+                       PLARGE_INTEGER DataSize);
+
 ULONG
 AttributeAllocatedLength(PNTFS_ATTR_RECORD AttrRecord);
 
@@ -766,6 +782,11 @@
 ReadFileRecord(PDEVICE_EXTENSION Vcb,
                ULONGLONG index,
                PFILE_RECORD_HEADER file);
+
+NTSTATUS
+UpdateFileRecord(PDEVICE_EXTENSION Vcb,
+                 ULONGLONG index,
+                 PFILE_RECORD_HEADER file);
 
 NTSTATUS
 FindAttribute(PDEVICE_EXTENSION Vcb,
@@ -773,7 +794,8 @@
               ULONG Type,
               PCWSTR Name,
               ULONG NameLength,
-              PNTFS_ATTR_CONTEXT * AttrCtx);
+              PNTFS_ATTR_CONTEXT * AttrCtx,
+              PULONG Offset);
 
 VOID
 ReadVCN(PDEVICE_EXTENSION Vcb,
@@ -788,6 +810,10 @@
                          PNTFS_RECORD_HEADER Record);
 
 NTSTATUS
+AddFixupArray(PDEVICE_EXTENSION Vcb,
+    PFILE_RECORD_HEADER Record);
+
+NTSTATUS
 ReadLCN(PDEVICE_EXTENSION Vcb,
         ULONGLONG lcn,
         ULONG count,

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/rw.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/rw.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/rw.c	[iso-8859-1] Wed Jun 22 21:20:50
2016
@@ -95,7 +95,7 @@
     }
 
 
-    Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream,
wcslen(Fcb->Stream), &DataContext);
+    Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream,
wcslen(Fcb->Stream), &DataContext, NULL);
     if (!NT_SUCCESS(Status))
     {
         NTSTATUS BrowseStatus;
@@ -306,6 +306,7 @@
     PNTFS_FCB Fcb;
     PFILE_RECORD_HEADER FileRecord;
     PNTFS_ATTR_CONTEXT DataContext;
+    ULONG AttributeOffset;
     ULONGLONG StreamSize;
 
     DPRINT("NtfsWriteFile(%p, %p, %p, %u, %u, %x, %p)\n", DeviceExt,
FileObject, Buffer, Length, WriteOffset, IrpFlags, LengthWritten);
@@ -358,9 +359,10 @@
 
     DPRINT("Found record for %wS\n", Fcb->ObjectName);
 
-    // Find the attribute (in the NTFS sense of the word) with the data stream for our
file
+    // Find the attribute with the data stream for our file
     DPRINT("Finding Data Attribute...\n");
-    Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream,
wcslen(Fcb->Stream), &DataContext);
+    Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream,
wcslen(Fcb->Stream), &DataContext,
+                           &AttributeOffset);
 
     // Did we fail to find the attribute?
     if (!NT_SUCCESS(Status))
@@ -402,13 +404,39 @@
     // Are we trying to write beyond the end of the stream?
     if (WriteOffset + Length > StreamSize)
     {
-        // TODO: allocate additional clusters as needed and expand stream
-        DPRINT1("WriteOffset: %lu\tLength: %lu\tStreamSize: %I64u\n",
WriteOffset, Length, StreamSize);
-        DPRINT1("TODO: Stream embiggening (appending files) is not yet
supported!\n");
-        ReleaseAttributeContext(DataContext);
-        ExFreePoolWithTag(FileRecord, TAG_NTFS);
-        *LengthWritten = 0;             // We didn't write anything
-        return STATUS_ACCESS_DENIED;    // temporarily; we don't change file sizes
yet
+        // is increasing the stream size allowed?
+        if (!(Fcb->Flags & FCB_IS_VOLUME) &&
+            !(IrpFlags & IRP_PAGING_IO))
+        {
+            LARGE_INTEGER DataSize;
+            ULONGLONG AllocationSize;
+
+            DataSize.QuadPart = WriteOffset + Length;
+
+            AllocationSize = ROUND_UP(DataSize.QuadPart,
Fcb->Vcb->NtfsInfo.BytesPerCluster);
+
+            // set the attribute data length
+            Status = SetAttributeDataLength(FileObject, Fcb, DataContext,
AttributeOffset, FileRecord, DeviceExt, &DataSize);
+            
+            if (!NT_SUCCESS(Status))
+            {
+                ReleaseAttributeContext(DataContext);
+                ExFreePoolWithTag(FileRecord, TAG_NTFS);
+                *LengthWritten = 0;
+                return Status;
+            }
+
+            // now we need to update this file's size in every directory index entry
that references it
+            // (saved for a later commit)
+        }
+        else
+        {
+            // TODO - just fail for now
+            ReleaseAttributeContext(DataContext);
+            ExFreePoolWithTag(FileRecord, TAG_NTFS);
+            *LengthWritten = 0;
+            return STATUS_ACCESS_DENIED;
+        }
     }
 
     DPRINT("Length: %lu\tWriteOffset: %lu\tStreamSize: %I64u\n", Length,
WriteOffset, StreamSize);

Modified: branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/volinfo.c
URL:
http://svn.reactos.org/svn/reactos/branches/GSoC_2016/NTFS/drivers/filesyst…
==============================================================================
--- branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/volinfo.c	[iso-8859-1] (original)
+++ branches/GSoC_2016/NTFS/drivers/filesystems/ntfs/volinfo.c	[iso-8859-1] Wed Jun 22
21:20:50 2016
@@ -62,7 +62,7 @@
         return 0;
     }
 
-    Status = FindAttribute(DeviceExt, BitmapRecord, AttributeData, L"", 0,
&DataContext);
+    Status = FindAttribute(DeviceExt, BitmapRecord, AttributeData, L"", 0,
&DataContext, NULL);
     if (!NT_SUCCESS(Status))
     {
         ExFreePoolWithTag(BitmapRecord, TAG_NTFS);