Changeset 18179 in vbox for trunk/src/VBox/Devices/Storage/VmdkHDDCore.cpp

Timestamp:

Mar 24, 2009 1:25:13 PM (16 years ago)

Author:

vboxsync

Message:

Storage/VMDK: Make the descriptor bigger if it is unreasonably small and we might want to add more data to it.

File:

• trunk/src/VBox/Devices/Storage/VmdkHDDCore.cpp (modified) (2 diffs)

trunk/src/VBox/Devices/Storage/VmdkHDDCore.cpp

@@ -2905 +2905 @@
         if (RT_FAILURE(rc))
             goto out;
+
         /* As we're dealing with a monolithic image here, there must
          * be a descriptor embedded in the image file. */
@@ -2911 +2912 @@
             rc = vmdkError(pImage, VERR_VD_VMDK_INVALID_HEADER, RT_SRC_POS, N_("VMDK: monolithic image without descriptor in '%s'"), pImage->pszFilename);
             goto out;
+        }
+        /* HACK: extend the descriptor if it is unusually small and it fits in
+         * the unused space after the image header. Allows opening VMDK files
+         * with extremely small descriptor in read/write mode. */
+        if (    !(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
+            &&  pExtent->cDescriptorSectors < 3
+            &&  (int64_t)pExtent->uSectorGD - pExtent->uDescriptorSector >= 4
+            &&  (!pExtent->uSectorRGD || (int64_t)pExtent->uSectorRGD - pExtent->uDescriptorSector >= 4))
+        {
+            pExtent->cDescriptorSectors = 4;
+            pExtent->fMetaDirty = true;
         }
         /* Read the descriptor from the extent. */