reactos/lib/rtl/mem.c

   1
   2 /* $Id$
   3  *
   4  * COPYRIGHT:       See COPYING in the top level directory
   5  * PROJECT:         ReactOS kernel
   6  * FILE:            lib/rtl/mem.c
   7  * PURPOSE:         Memory functions
   8  * PROGRAMMER:      David Welch (welch@mcmail.com)
   9  * UPDATE HISTORY:
  10  *                  Created 22/05/98
  11  */
  12
  13 /* INCLUDES *****************************************************************/
  14
  15 #include "rtl.h"
  16
  17 #define NDEBUG
  18 #include <debug.h>
  19
  20
  21
  22
  23 /* FUNCTIONS *****************************************************************/
  24
  25 /******************************************************************************
  26  *  RtlCompareMemory   [NTDLL.@]
  27  *
  28  * Compare one block of memory with another
  29  *
  30  * PARAMS
  31  *  Source1 [I] Source block
  32  *  Source2 [I] Block to compare to Source1
  33  *  Length  [I] Number of bytes to fill
  34  *
  35  * RETURNS
  36  *  The length of the first byte at which Source1 and Source2 differ, or Length
  37  *  if they are the same.
  38  *
  39  * @implemented
  40  */
  41 SIZE_T STDCALL
  42 RtlCompareMemory(IN const VOID *Source1,
  43                  IN const VOID *Source2,
  44                  IN SIZE_T Length)
  45 {
  46    SIZE_T i;
  47    for(i=0; (i<Length) && (((PUCHAR)Source1)[i]==((PUCHAR)Source2)[i]); i++)
  48       ;
  49    return i;
  50 }
  51
  52
  53 /*
  54  * @implemented
  55  */
  56 ULONG
  57 STDCALL
  58 RtlCompareMemoryUlong (
  59    PVOID Source,
  60    ULONG Length,
  61    ULONG Value
  62 )
  63 /*
  64  * FUNCTION: Compares a block of ULONGs with an ULONG and returns the number of equal bytes
  65  * ARGUMENTS:
  66  *      Source = Block to compare
  67  *      Length = Number of bytes to compare
  68  *      Value = Value to compare
  69  * RETURNS: Number of equal bytes
  70  */
  71 {
  72    PULONG ptr = (PULONG)Source;
  73    ULONG  len = Length / sizeof(ULONG);
  74    ULONG i;
  75
  76    for (i = 0; i < len; i++)
  77    {
  78       if (*ptr != Value)
  79          break;
  80       ptr++;
  81    }
  82
  83    return (ULONG)((PCHAR)ptr - (PCHAR)Source);
  84 }
  85
  86
  87 /*
  88  * @implemented
  89  */
  90 VOID
  91 STDCALL
  92 RtlFillMemory (
  93    PVOID Destination,
  94    ULONG Length,
  95    UCHAR Fill
  96 )
  97 {
  98    memset(Destination, Fill, Length);
  99 }
 100
 101
 102
 103 /*
 104  * @implemented
 105  */
 106 VOID
 107 STDCALL
 108 RtlFillMemoryUlong (
 109    PVOID Destination,
 110    ULONG Length,
 111    ULONG Fill
 112 )
 113 {
 114    PULONG Dest  = Destination;
 115    ULONG  Count = Length / sizeof(ULONG);
 116
 117    while (Count > 0)
 118    {
 119       *Dest = Fill;
 120       Dest++;
 121       Count--;
 122    }
 123 }
 124
 125
 126
 127 /*
 128  * @implemented
 129  */
 130 VOID
 131 STDCALL
 132 RtlMoveMemory (
 133    PVOID    Destination,
 134    CONST VOID  * Source,
 135    ULONG    Length
 136 )
 137 {
 138    memmove (
 139       Destination,
 140       Source,
 141       Length
 142    );
 143 }
 144
 145 /*
 146 * @unimplemented
 147 */
 148 VOID
 149 FASTCALL
 150 RtlPrefetchMemoryNonTemporal(
 151         IN PVOID Source,
 152         IN SIZE_T Length
 153         )
 154 {
 155         UNIMPLEMENTED;
 156 }
 157
 158 /*
 159  * @implemented
 160  */
 161 VOID
 162 STDCALL
 163 RtlZeroMemory (
 164    PVOID Destination,
 165    ULONG Length
 166 )
 167 {
 168    RtlFillMemory (
 169       Destination,
 170       Length,
 171       0
 172    );
 173 }
 174
 175
 176 /*************************************************************************
 177  * RtlUshortByteSwap
 178  *
 179  * Swap the bytes of an unsigned short value.
 180  *
 181  * NOTES
 182  * Based on the inline versions in Wine winternl.h
 183  *
 184  * @implemented
 185  */
 186 USHORT FASTCALL
 187 RtlUshortByteSwap (IN USHORT Source)
 188 {
 189    return (Source >> 8) | (Source << 8);
 190 }
 191
 192
 193
 194 /*************************************************************************
 195  * RtlUlongByteSwap    [NTDLL.@]
 196  *
 197  * Swap the bytes of an unsigned int value.
 198  *
 199  * NOTES
 200  * Based on the inline versions in Wine winternl.h
 201  *
 202  * @implemented
 203  */
 204 ULONG
 205 FASTCALL
 206 RtlUlongByteSwap(
 207    IN ULONG Source
 208 )
 209 {
 210 #if defined(__i386__) && defined(__GNUC__)
 211    ULONG ret;
 212 __asm__("bswap %0" : "=r" (ret) : "0" (Source) );
 213    return ret;
 214 #else
 215
 216    return ((ULONG)RtlUshortByteSwap((USHORT)Source) << 16) | RtlUshortByteSwap((USHORT)(Source >> 16));
 217 #endif
 218 }
 219
 220
 221 /*************************************************************************
 222  * RtlUlonglongByteSwap
 223  *
 224  * Swap the bytes of an unsigned long long value.
 225  *
 226  * PARAMS
 227  *  i [I] Value to swap bytes of
 228  *
 229  * RETURNS
 230  *  The value with its bytes swapped.
 231  *
 232  * @implemented
 233  */
 234 ULONGLONG FASTCALL
 235 RtlUlonglongByteSwap (IN ULONGLONG Source)
 236 {
 237    return ((ULONGLONG) RtlUlongByteSwap (Source) << 32) | RtlUlongByteSwap (Source>>32);
 238 }
 239
 240
 241 /* EOF */