ULONGLONG
NtfsGetFreeClusters(PDEVICE_EXTENSION DeviceExt)
{
- UNIMPLEMENTED;
- return 0;
+ NTSTATUS Status;
+ PFILE_RECORD_HEADER BitmapRecord;
+ PNTFS_ATTR_CONTEXT DataContext;
+ ULONGLONG BitmapDataSize;
+ PCHAR BitmapData;
+ ULONGLONG FreeClusters = 0;
+ ULONG Read = 0;
+ RTL_BITMAP Bitmap;
+
+ DPRINT1("NtfsGetFreeClusters(%p)\n", DeviceExt);
+
+ BitmapRecord = ExAllocatePoolWithTag(NonPagedPool,
+ DeviceExt->NtfsInfo.BytesPerFileRecord,
+ TAG_NTFS);
+ if (BitmapRecord == NULL)
+ {
+ return 0;
+ }
+
+ Status = ReadFileRecord(DeviceExt, NTFS_FILE_BITMAP, BitmapRecord);
+ if (!NT_SUCCESS(Status))
+ {
+ ExFreePoolWithTag(BitmapRecord, TAG_NTFS);
+ return 0;
+ }
+
+ Status = FindAttribute(DeviceExt, BitmapRecord, AttributeData, L"", 0, &DataContext);
+ if (!NT_SUCCESS(Status))
+ {
+ ExFreePoolWithTag(BitmapRecord, TAG_NTFS);
+ return 0;
+ }
+
+ BitmapDataSize = AttributeDataLength(&DataContext->Record);
+ ASSERT((BitmapDataSize * 8) >= (DeviceExt->NtfsInfo.SectorCount / DeviceExt->NtfsInfo.SectorsPerCluster));
+ BitmapData = ExAllocatePoolWithTag(NonPagedPool, BitmapDataSize, TAG_NTFS);
+ if (BitmapData == NULL)
+ {
+ ReleaseAttributeContext(DataContext);
+ ExFreePoolWithTag(BitmapRecord, TAG_NTFS);
+ return 0;
+ }
+
+ /* FIXME: Totally underoptimized! */
+ for (; Read < BitmapDataSize; Read += DeviceExt->NtfsInfo.BytesPerSector)
+ {
+ ReadAttribute(DeviceExt, DataContext, Read, (PCHAR)((ULONG_PTR)BitmapData + Read), DeviceExt->NtfsInfo.BytesPerSector);
+ }
+ ReleaseAttributeContext(DataContext);
+
+ DPRINT1("Total clusters: %I64x\n", DeviceExt->NtfsInfo.SectorCount / DeviceExt->NtfsInfo.SectorsPerCluster);
+ DPRINT1("Total clusters in bitmap: %I64x\n", BitmapDataSize * 8);
+ DPRINT1("Diff in size: %I64d B\n", ((BitmapDataSize * 8) - (DeviceExt->NtfsInfo.SectorCount / DeviceExt->NtfsInfo.SectorsPerCluster)) * DeviceExt->NtfsInfo.SectorsPerCluster * DeviceExt->NtfsInfo.BytesPerSector);
+
+ RtlInitializeBitMap(&Bitmap, (PULONG)BitmapData, DeviceExt->NtfsInfo.SectorCount / DeviceExt->NtfsInfo.SectorsPerCluster);
+ FreeClusters = RtlNumberOfClearBits(&Bitmap);
+
+ ExFreePoolWithTag(BitmapData, TAG_NTFS);
+ ExFreePoolWithTag(BitmapRecord, TAG_NTFS);
+
+ return FreeClusters;
}
static