.. _hashpack-hashunpack:



HashPack, HashUnpack
====================


Packs/unpacks the IppsHashState or IppsHashState_rmf context into/from a
user-defined buffer.


Syntax
------


IppStatus ippsHashPack (const IppsHashState\* pCtx, Ipp8u\* pBuffer, int
bufSize);


IppStatus ippsHashPack_rmf(const IppsHashState_rmf\* pCtx, Ipp8u\*
pBuffer, int bufferSize);


IppStatus ippsHashUnpack (const Ipp8u\* pBuffer, IppsHashState\* pCtx);


IppStatus ippsHashUnpack_rmf(const Ipp8u\* pBuffer, IppsHashState_rmf\*
pCtx);


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


``ippcp.h``


Parameters
----------


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

   * -     pCtx   
     -  Pointer to the IppsHashState or IppsHashState_rmf context.
   * -     pBuffer   
     -  Pointer to the user-defined buffer.
   * -     bufSize, bufferSize   
     -  The size of the user-defined buffer in bytes.




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


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


The value of the bufSize parameter must be not less than the size of
IppsHashState or IppsHashState_rmf context. Call the
`HashGetSize <hashgetsize.html>`__
function prior to HashPack to determine the size of the buffer.


.. note::


   This function has a *reduced memory footprint* version. To learn
   more, see `Reduced Memory Footprint
   Functions <one-way-hash-primitives.html>`__.


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.    
   * -     ippStsMemErr   
     -     Indicates an error condition if the value of bufSize is less than the size of the IppsHashState context.   
   * -     ippStsContextMatchErr   
     -     Indicates an error condition in a ippsHashPack_rmf call if the context parameter does not match the operation.   
   * -     ippStsNoMem   
     -     Indicates an error condition if the value of bufferSize is less than the size of the IppsHashState_rmf context.