.. _sha512pack-sha512unpack:

SHA512Pack, SHA512Unpack
========================


Packs/unpacks the IppsSHA512State context into/from a user-defined
buffer.


Syntax
------


IppStatus ippsSHA512Pack (const IppsSHA512State\* pCtx, Ipp8u\*
pBuffer);


IppStatus ippsSHA512Unpack (const Ipp8u\* pBuffer, IppsSHA512State\*
pCtx);


Include Files
-------------


``ippcp.h``


Parameters
----------


.. list-table:: 
   :header-rows: 0

   * -     pCtx   
     -  Pointer to the IppsSHA512State context.
   * -     pBuffer   
     -  Pointer to the user-defined buffer.




Description
-----------


The SHA512Pack function transforms the \*pCtx context to a
position-independent form and stores it in the \*pBuffer buffer. The
SHA512Unpack function performs the inverse operation, that is,
transforms the contents of the \*pBuffer buffer into a normal
IppsSHA512State context. The SHA512Pack and SHA512Unpack functions
enable replacing the position-dependent IppsSHA512State context in the
memory.


Call the
`SHA512GetSize <sha512getsize.html>`__
function prior to SHA512Pack/SHA512Unpack to determine the size of the
buffer.


Return Values
-------------


.. list-table:: 
   :header-rows: 0

   * -     ippStsNoErr   
     -  Indicates no error. Any other value indicates an error or warning.
   * -     ippStsNullPtrErr   
     -  Indicates an error condition if any of the specified pointers is NULL.
   * -     ippStsContextMatchErr   
     -  Indicates an error condition if the context parameter does not match the operation.