drivers/filters/fltmgr/Volume.c

   1 /*
   2 * PROJECT:         Filesystem Filter Manager
   3 * LICENSE:         GPL - See COPYING in the top level directory
   4 * FILE:            drivers/filters/fltmgr/Context.c
   5 * PURPOSE:         Contains routines for the volume
   6 * PROGRAMMERS:     Ged Murphy (gedmurphy@reactos.org)
   7 */
   8
   9 /* INCLUDES ******************************************************************/
  10
  11 #include "fltmgr.h"
  12 #include "fltmgrint.h"
  13
  14 #define NDEBUG
  15 #include <debug.h>
  16
  17
  18 /* DATA *********************************************************************/
  19
  20
  21
  22 /* EXPORTED FUNCTIONS ******************************************************/
  23
  24 NTSTATUS
  25 FLTAPI
  26 FltGetVolumeProperties(
  27     _In_ PFLT_VOLUME Volume,
  28     _Out_writes_bytes_to_opt_(VolumePropertiesLength, *LengthReturned) PFLT_VOLUME_PROPERTIES VolumeProperties,
  29     _In_ ULONG VolumePropertiesLength,
  30     _Out_ PULONG LengthReturned
  31 )
  32 {
  33     ULONG BufferRequired;
  34     ULONG BytesWritten;
  35     PCHAR Ptr;
  36     NTSTATUS Status;
  37
  38     /* Calculate the required buffer size */
  39     BufferRequired = sizeof(FLT_VOLUME_PROPERTIES) +
  40                      Volume->CDODriverName.Length +
  41                      Volume->DeviceName.Length +
  42                      Volume->CDODeviceName.Length;
  43
  44     /* If we don't have enough buffer to fill in the fixed struct, return with the required size */
  45     if (VolumePropertiesLength < sizeof(FLT_VOLUME_PROPERTIES))
  46     {
  47         *LengthReturned = BufferRequired;
  48         return STATUS_BUFFER_TOO_SMALL;
  49     }
  50
  51     /* Clear out the buffer */
  52     RtlZeroMemory(VolumeProperties, sizeof(FLT_VOLUME_PROPERTIES));
  53
  54     /* Fill in the fixed data */
  55     VolumeProperties->DeviceType = Volume->DeviceObject->DeviceType;
  56     VolumeProperties->DeviceObjectFlags = Volume->DeviceObject->Flags;
  57     VolumeProperties->AlignmentRequirement = Volume->DeviceObject->AlignmentRequirement;
  58     VolumeProperties->SectorSize = Volume->DeviceObject->SectorSize;
  59     if (Volume->DiskDeviceObject)
  60     {
  61         VolumeProperties->DeviceCharacteristics = Volume->DiskDeviceObject->Characteristics;
  62     }
  63     else
  64     {
  65         VolumeProperties->DeviceCharacteristics = Volume->DeviceObject->Characteristics;
  66     }
  67
  68     /* So far we've written the fixed struct data */
  69     BytesWritten = sizeof(FLT_VOLUME_PROPERTIES);
  70     Ptr = (PCHAR)(VolumeProperties + 1);
  71
  72     /* Make sure we have enough room to add the dynamic data */
  73     if (VolumePropertiesLength >= BufferRequired)
  74     {
  75         /* Add the FS device name */
  76         VolumeProperties->FileSystemDeviceName.Length = 0;
  77         VolumeProperties->FileSystemDeviceName.MaximumLength = Volume->CDODeviceName.Length;
  78         VolumeProperties->FileSystemDeviceName.Buffer = (PWCH)Ptr;
  79         RtlCopyUnicodeString(&VolumeProperties->FileSystemDeviceName, &Volume->CDODeviceName);
  80         Ptr += VolumeProperties->FileSystemDeviceName.Length;
  81
  82         /* Add the driver name */
  83         VolumeProperties->FileSystemDriverName.Length = 0;
  84         VolumeProperties->FileSystemDriverName.MaximumLength = Volume->CDODriverName.Length;
  85         VolumeProperties->FileSystemDriverName.Buffer = (PWCH)Ptr;
  86         RtlCopyUnicodeString(&VolumeProperties->FileSystemDriverName, &Volume->CDODriverName);
  87         Ptr += VolumeProperties->FileSystemDriverName.Length;
  88
  89         /* Add the volume name */
  90         VolumeProperties->RealDeviceName.Length = 0;
  91         VolumeProperties->RealDeviceName.MaximumLength = Volume->DeviceName.Length;
  92         VolumeProperties->RealDeviceName.Buffer = (PWCH)Ptr;
  93         RtlCopyUnicodeString(&VolumeProperties->RealDeviceName, &Volume->DeviceName);
  94
  95         BytesWritten = BufferRequired;
  96
  97         Status = STATUS_SUCCESS;
  98     }
  99     else
 100     {
 101         Status = STATUS_BUFFER_OVERFLOW;
 102     }
 103
 104     /* Set the number of bytes we wrote and return */
 105     *LengthReturned = BytesWritten;
 106     return Status;
 107 }
 108
 109
 110 /* INTERNAL FUNCTIONS ******************************************************/