KSSTREAM_POINTER_OFFSET - NtDoc
Native API online documentation, based on the System Informer
(formerly Process Hacker) phnt
headers
// ks.h
typedef struct _KSSTREAM_POINTER_OFFSET {
union {
PUCHAR Data;
PKSMAPPING Mappings;
};
PUCHAR Data;
PVOID Alignment;
ULONG Count;
ULONG Remaining;
} KSSTREAM_POINTER_OFFSET, *PKSSTREAM_POINTER_OFFSET;
View the official Windows Driver Kit DDI referenceNo description available.
The KSSTREAM_POINTER_OFFSET structure indexes bytes or mappings within a frame.
MappingsA pointer to the first element in an array of KSMAPPING structures. Specify Mappings if the minidriver sets the KSPIN_FLAG_GENERATE_MAPPINGS flag in the Flags member of KSPIN_DESCRIPTOR_EX. In this case, the Mappings array describes contiguous chunks of physical memory that the client can use to set up a scatter/gather DMA operation with hardware.
DataA pointer to a buffer containing input data or a buffer to which data is to be output. Specify Data if the minidriver does not set the KSPIN_FLAG_GENERATE_MAPPINGS flag in the Flags member of KSPIN_DESCRIPTOR_EX.
AlignmentCountIf Data is specified above, Count contains the total number of bytes of data available in the Data buffer. If Mappings is specified above, Count contains the total number of mappings in the Mappings table. Count does not change unless the stream pointer moves to a different Frame.
RemainingThis member specifies a value of type ULONG that indicates the number of bytes or mappings remaining at and ahead of the given stream pointer. This value is equal to Count minus the number of bytes or mappings that have been processed. Remaining starts equal to Count and decreases as the stream pointer moves forward.
See also AVStream DMA Services.