update for HEAD-2003021201

[reactos.git] / drivers / fs / cdfs / rw.c

diff --git a/drivers/fs/cdfs/rw.c b/drivers/fs/cdfs/rw.c
index 75eda1b..82ae382 100644 (file)
--- a/drivers/fs/cdfs/rw.c
+++ b/drivers/fs/cdfs/rw.c
@@ -68,24 +68,23 @@ CdfsReadFile(PDEVICE_EXTENSION DeviceExt,
   *LengthRead = 0;
 
   if (Length == 0)
-    return STATUS_SUCCESS;
+    return(STATUS_SUCCESS);
 
   Ccb = (PCCB)FileObject->FsContext2;
   Fcb = Ccb->Fcb;
 
-  if (ReadOffset + Length > Fcb->Entry.DataLengthL)
-    Length = Fcb->Entry.DataLengthL - ReadOffset;
+  if (ReadOffset >= Fcb->Entry.DataLengthL)
+    return(STATUS_END_OF_FILE);
 
   DPRINT("Reading %d bytes at %d\n", Length, ReadOffset);
 
-  if (Length == 0)
-    return(STATUS_UNSUCCESSFUL);
-
   if (!(IrpFlags & (IRP_NOCACHE|IRP_PAGING_IO)))
     {
       LARGE_INTEGER FileOffset;
       IO_STATUS_BLOCK IoStatus;
 
+      if (ReadOffset + Length > Fcb->Entry.DataLengthL)
+         Length = Fcb->Entry.DataLengthL - ReadOffset;
       if (FileObject->PrivateCacheMap == NULL)
       {
          CcRosInitializeFileCache(FileObject, &Fcb->RFCB.Bcb, PAGE_SIZE);
@@ -103,60 +102,25 @@ CdfsReadFile(PDEVICE_EXTENSION DeviceExt,
       return(IoStatus.Status);
     }
 
-  if ((ReadOffset % BLOCKSIZE) != 0)
+  if ((ReadOffset % BLOCKSIZE) != 0 || (Length % BLOCKSIZE) != 0)
     {
-      TempLength = min(Length, BLOCKSIZE - (ReadOffset % BLOCKSIZE));
-      TempBuffer = ExAllocatePool(NonPagedPool, BLOCKSIZE);
-
-      Status = CdfsReadSectors(DeviceExt->StorageDevice,
-                              Fcb->Entry.ExtentLocationL + (ReadOffset / BLOCKSIZE),
-                              1,
-                              TempBuffer);
-      if (NT_SUCCESS(Status))
-       {
-         memcpy(Buffer, TempBuffer + (ReadOffset % BLOCKSIZE), TempLength);
-         (*LengthRead) = (*LengthRead) + TempLength;
-         Length = Length - TempLength;
-         Buffer = Buffer + TempLength;
-         ReadOffset = ReadOffset + TempLength;
-       }
-      ExFreePool(TempBuffer);
+      return STATUS_INVALID_PARAMETER;
     }
+  if (ReadOffset + Length > ROUND_UP(Fcb->Entry.DataLengthL, BLOCKSIZE))
+    Length = ROUND_UP(Fcb->Entry.DataLengthL, BLOCKSIZE) - ReadOffset;
 
-  DPRINT("Status %lx\n", Status);
-
-  if ((Length / BLOCKSIZE) != 0 && NT_SUCCESS(Status))
-    {
-      TempLength = ROUND_DOWN(Length, BLOCKSIZE);
-      Status = CdfsReadSectors(DeviceExt->StorageDevice,
-                              Fcb->Entry.ExtentLocationL + (ReadOffset / BLOCKSIZE),
-                              TempLength / BLOCKSIZE,
-                              Buffer);
-      if (NT_SUCCESS(Status))
-       {
-         (*LengthRead) = (*LengthRead) + TempLength;
-         Length = Length - TempLength;
-         Buffer = Buffer + TempLength;
-         ReadOffset = ReadOffset + TempLength;
-       }
-    }
-
-  DPRINT("Status %lx\n", Status);
-
-  if (Length > 0 && NT_SUCCESS(Status))
+  Status = CdfsReadSectors(DeviceExt->StorageDevice,
+                          Fcb->Entry.ExtentLocationL + (ReadOffset / BLOCKSIZE),
+                          Length / BLOCKSIZE,
+                          Buffer);
+  if (NT_SUCCESS(Status))
     {
-      TempBuffer = ExAllocatePool(NonPagedPool, BLOCKSIZE);
-
-      Status = CdfsReadSectors(DeviceExt->StorageDevice,
-                              Fcb->Entry.ExtentLocationL + (ReadOffset / BLOCKSIZE),
-                              1,
-                              TempBuffer);
-      if (NT_SUCCESS(Status))
-       {
-         memcpy(Buffer, TempBuffer, Length);
-         (*LengthRead) = (*LengthRead) + Length;
-       }
-      ExFreePool(TempBuffer);
+      *LengthRead = Length;
+      if (Length + ReadOffset > Fcb->Entry.DataLengthL)
+      {
+       memset(Buffer + Fcb->Entry.DataLengthL - ReadOffset, 
+              0, Length + ReadOffset - Fcb->Entry.DataLengthL);
+      }
     }
 
   return(Status);