mem.c

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/* COPYRIGHT:       See COPYING in the top level directory
 * PROJECT:         ReactOS system libraries
 * FILE:            lib/rtl/mem.c
 * PURPOSE:         Memory functions
 * PROGRAMMER:      David Welch (welch@mcmail.com)
 */

/* INCLUDES *****************************************************************/

#include <rtl.h>

#define NDEBUG
#include <debug.h>


/* FUNCTIONS *****************************************************************/

/******************************************************************************
 *  RtlCompareMemory   [NTDLL.@]
 *
 * Compare one block of memory with another
 *
 * PARAMS
 *  Source1 [I] Source block
 *  Source2 [I] Block to compare to Source1
 *  Length  [I] Number of bytes to fill
 *
 * RETURNS
 *  The length of the first byte at which Source1 and Source2 differ, or Length
 *  if they are the same.
 *
 * @implemented
 */
SIZE_T NTAPI
RtlCompareMemory(IN const VOID *Source1,
                 IN const VOID *Source2,
                 IN SIZE_T Length)
{
   SIZE_T i;
   for(i=0; (i<Length) && (((PUCHAR)Source1)[i]==((PUCHAR)Source2)[i]); i++)
      ;
   return i;
}


/*
 * @implemented
 */
SIZE_T
NTAPI
RtlCompareMemoryUlong (
   PVOID Source,
   SIZE_T Length,
   ULONG Value
)
/*
 * FUNCTION: Compares a block of ULONGs with an ULONG and returns the number of equal bytes
 * ARGUMENTS:
 *      Source = Block to compare
 *      Length = Number of bytes to compare
 *      Value = Value to compare
 * RETURNS: Number of equal bytes
 */
{
   PULONG ptr = (PULONG)Source;
   ULONG_PTR len = Length / sizeof(ULONG);
   ULONG_PTR i;

   for (i = 0; i < len; i++)
   {
      if (*ptr != Value)
         break;
      ptr++;
   }

   return (SIZE_T)((PCHAR)ptr - (PCHAR)Source);
}


#undef RtlFillMemory
/*
 * @implemented
 */
VOID
NTAPI
RtlFillMemory (
   PVOID Destination,
   SIZE_T Length,
   UCHAR Fill
)
{
   memset(Destination, Fill, Length);
}



/*
 * @implemented
 */
VOID
NTAPI
RtlFillMemoryUlong (
   PVOID Destination,
   SIZE_T Length,
   ULONG Fill
)
{
   PULONG Dest  = Destination;
   SIZE_T Count = Length / sizeof(ULONG);

   while (Count > 0)
   {
      *Dest = Fill;
      Dest++;
      Count--;
   }
}


#undef RtlMoveMemory
/*
 * @implemented
 */
VOID
NTAPI
RtlMoveMemory (
   PVOID    Destination,
   CONST VOID  * Source,
   SIZE_T   Length
)
{
   memmove (
      Destination,
      Source,
      Length
   );
}

/*
* @implemented
*/
VOID
FASTCALL
RtlPrefetchMemoryNonTemporal(
    IN PVOID Source,
    IN SIZE_T Length
    )
{
    /* By nature of prefetch, this is non-portable. */
    (void)Source;
    (void)Length;
}


#undef RtlZeroMemory
/*
 * @implemented
 */
VOID
NTAPI
RtlZeroMemory (
   PVOID Destination,
   SIZE_T Length
)
{
   RtlFillMemory (
      Destination,
      Length,
      0
   );
}

/* EOF */