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 <ddk/ntddk.h>
  16 #include <string.h>
  17
  18 #define NDEBUG
  19 #include <debug.h>
  20
  21
  22
  23
  24 /* FUNCTIONS *****************************************************************/
  25
  26 /******************************************************************************
  27  *  RtlCompareMemory   [NTDLL.@]
  28  *
  29  * Compare one block of memory with another
  30  *
  31  * PARAMS
  32  *  Source1 [I] Source block
  33  *  Source2 [I] Block to compare to Source1
  34  *  Length  [I] Number of bytes to fill
  35  *
  36  * RETURNS
  37  *  The length of the first byte at which Source1 and Source2 differ, or Length
  38  *  if they are the same.
  39  *
  40  * @implemented
  41  */
  42 SIZE_T STDCALL
  43 RtlCompareMemory(IN const VOID *Source1,
  44                  IN const VOID *Source2,
  45                  IN SIZE_T Length)
  46 {
  47    SIZE_T i;
  48    for(i=0; (i<Length) && (((PUCHAR)Source1)[i]==((PUCHAR)Source2)[i]); i++)
  49       ;
  50    return i;
  51 }
  52
  53
  54 /*
  55  * @implemented
  56  */
  57 ULONG
  58 STDCALL
  59 RtlCompareMemoryUlong (
  60    PVOID Source,
  61    ULONG Length,
  62    ULONG Value
  63 )
  64 /*
  65  * FUNCTION: Compares a block of ULONGs with an ULONG and returns the number of equal bytes
  66  * ARGUMENTS:
  67  *      Source = Block to compare
  68  *      Length = Number of bytes to compare
  69  *      Value = Value to compare
  70  * RETURNS: Number of equal bytes
  71  */
  72 {
  73    PULONG ptr = (PULONG)Source;
  74    ULONG  len = Length / sizeof(ULONG);
  75    ULONG i;
  76
  77    for (i = 0; i < len; i++)
  78    {
  79       if (*ptr != Value)
  80          break;
  81       ptr++;
  82    }
  83
  84    return (ULONG)((PCHAR)ptr - (PCHAR)Source);
  85 }
  86
  87
  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
 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  * @implemented
 161  */
 162 VOID
 163 STDCALL
 164 RtlZeroMemory (
 165    PVOID Destination,
 166    ULONG Length
 167 )
 168 {
 169    RtlFillMemory (
 170       Destination,
 171       Length,
 172       0
 173    );
 174 }
 175
 176
 177 /*************************************************************************
 178  * RtlUshortByteSwap
 179  *
 180  * Swap the bytes of an unsigned short value.
 181  *
 182  * NOTES
 183  * Based on the inline versions in Wine winternl.h
 184  *
 185  * @implemented
 186  */
 187 USHORT FASTCALL
 188 RtlUshortByteSwap (IN USHORT Source)
 189 {
 190    return (Source >> 8) | (Source << 8);
 191 }
 192
 193
 194
 195 /*************************************************************************
 196  * RtlUlongByteSwap    [NTDLL.@]
 197  *
 198  * Swap the bytes of an unsigned int value.
 199  *
 200  * NOTES
 201  * Based on the inline versions in Wine winternl.h
 202  *
 203  * @implemented
 204  */
 205 ULONG
 206 FASTCALL
 207 RtlUlongByteSwap(
 208    IN ULONG Source
 209 )
 210 {
 211 #if defined(__i386__) && defined(__GNUC__)
 212    ULONG ret;
 213 __asm__("bswap %0" : "=r" (ret) : "0" (Source) );
 214    return ret;
 215 #else
 216
 217    return ((ULONG)RtlUshortByteSwap((USHORT)Source) << 16) | RtlUshortByteSwap((USHORT)(Source >> 16));
 218 #endif
 219 }
 220
 221
 222 /*************************************************************************
 223  * RtlUlonglongByteSwap
 224  *
 225  * Swap the bytes of an unsigned long long value.
 226  *
 227  * PARAMS
 228  *  i [I] Value to swap bytes of
 229  *
 230  * RETURNS
 231  *  The value with its bytes swapped.
 232  *
 233  * @implemented
 234  */
 235 ULONGLONG FASTCALL
 236 RtlUlonglongByteSwap (IN ULONGLONG Source)
 237 {
 238    return ((ULONGLONG) RtlUlongByteSwap (Source) << 32) | RtlUlongByteSwap (Source>>32);
 239 }
 240
 241
 242 /* EOF */