UDF 2.00 - OSTA - Optical Storage Technology Association

2.2.5 Unallocated Space Descriptor
struct UnallocatedSpaceDesc { /* ECMA 167 3/10.8 */
struct tag DescriptorTag;
Uint32 VolumeDescriptorSequenceNumber;
Uint32 NumberofAllocationDescriptors;
extent_ad AllocationDescriptors[];
}
This descriptor shall be recorded, even if there is no free volume space.
2.2.6 Logical Volume Integrity Descriptor
struct LogicalVolumeIntegrityDesc { /* ECMA 167 3/10.10 */
struct tag DescriptorTag,
Timestamp RecordingDateAndTime,
Uint32 IntegrityType,
struct extend_ad NextIntegrityExtent,
byte
LogicalVolumeContentsUse[32],
Uint32 NumberOfPartitions,
Uint32 LengthOfImplementationUse,
Uint32 FreeSpaceTable[],
Uint32 SizeTable[],
byte
ImplementationUse[]
}
The Logical Volume Integrity Descriptor is a structure that shall be written any
time the contents of the associated Logical Volume is modified. Through the
contents of the Logical Volume Integrity Descriptor an implementation can easily
answer the following useful questions:
1) Are the contents of the Logical Volume in a consistent state?
2) When was the last date and time that anything within the Logical
Volume was modified?
3) What is the total Logical Volume free space in logical blocks?
4) What is the total size of the Logical Volume in logical blocks?
5) What is the next available UniqueID for use within the Logical Volume?
6) Has some other implementation modified the contents of the logical
volume since the last time that the original implementation which created
the logical volume accessed it.
UDF 2.00 April 3, 1998
22