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 #undef RtlFillMemory
  88 /*
  89  * @implemented
  90  */
  91 VOID
  92 STDCALL
  93 RtlFillMemory (
  94    PVOID Destination,
  95    ULONG Length,
  96    UCHAR Fill
  97 )
  98 {
  99    memset(Destination, Fill, Length);
 100 }
 101
 102
 103
 104 /*
 105  * @implemented
 106  */
 107 VOID
 108 STDCALL
 109 RtlFillMemoryUlong (
 110    PVOID Destination,
 111    ULONG Length,
 112    ULONG Fill
 113 )
 114 {
 115    PULONG Dest  = Destination;
 116    ULONG  Count = Length / sizeof(ULONG);
 117
 118    while (Count > 0)
 119    {
 120       *Dest = Fill;
 121       Dest++;
 122       Count--;
 123    }
 124 }
 125
 126
 127 #undef RtlMoveMemory
 128 /*
 129  * @implemented
 130  */
 131 VOID
 132 STDCALL
 133 RtlMoveMemory (
 134    PVOID    Destination,
 135    CONST VOID  * Source,
 136    ULONG    Length
 137 )
 138 {
 139    memmove (
 140       Destination,
 141       Source,
 142       Length
 143    );
 144 }
 145
 146 /*
 147 * @unimplemented
 148 */
 149 VOID
 150 FASTCALL
 151 RtlPrefetchMemoryNonTemporal(
 152         IN PVOID Source,
 153         IN SIZE_T Length
 154         )
 155 {
 156         UNIMPLEMENTED;
 157 }
 158
 159
 160 #undef RtlZeroMemory
 161 /*
 162  * @implemented
 163  */
 164 VOID
 165 STDCALL
 166 RtlZeroMemory (
 167    PVOID Destination,
 168    ULONG Length
 169 )
 170 {
 171    RtlFillMemory (
 172       Destination,
 173       Length,
 174       0
 175    );
 176 }
 177
 178
 179 /*************************************************************************
 180  * RtlUshortByteSwap
 181  *
 182  * Swap the bytes of an unsigned short value.
 183  *
 184  * NOTES
 185  * Based on the inline versions in Wine winternl.h
 186  *
 187  * @implemented
 188  */
 189 USHORT FASTCALL
 190 RtlUshortByteSwap (IN USHORT Source)
 191 {
 192    return (Source >> 8) | (Source << 8);
 193 }
 194
 195
 196
 197 /*************************************************************************
 198  * RtlUlongByteSwap    [NTDLL.@]
 199  *
 200  * Swap the bytes of an unsigned int value.
 201  *
 202  * NOTES
 203  * Based on the inline versions in Wine winternl.h
 204  *
 205  * @implemented
 206  */
 207 ULONG
 208 FASTCALL
 209 RtlUlongByteSwap(
 210    IN ULONG Source
 211 )
 212 {
 213 #if defined(__i386__) && defined(__GNUC__)
 214    ULONG ret;
 215 __asm__("bswap %0" : "=r" (ret) : "0" (Source) );
 216    return ret;
 217 #else
 218
 219    return ((ULONG)RtlUshortByteSwap((USHORT)Source) << 16) | RtlUshortByteSwap((USHORT)(Source >> 16));
 220 #endif
 221 }
 222
 223
 224 /*************************************************************************
 225  * RtlUlonglongByteSwap
 226  *
 227  * Swap the bytes of an unsigned long long value.
 228  *
 229  * PARAMS
 230  *  i [I] Value to swap bytes of
 231  *
 232  * RETURNS
 233  *  The value with its bytes swapped.
 234  *
 235  * @implemented
 236  */
 237 ULONGLONG FASTCALL
 238 RtlUlonglongByteSwap (IN ULONGLONG Source)
 239 {
 240    return ((ULONGLONG) RtlUlongByteSwap (Source) << 32) | RtlUlongByteSwap (Source>>32);
 241 }
 242
 243
 244 /* EOF */