reactos/lib/rtl/mem.c

   1 /* COPYRIGHT:       See COPYING in the top level directory
   2  * PROJECT:         ReactOS system libraries
   3  * FILE:            lib/rtl/mem.c
   4  * PURPOSE:         Memory functions
   5  * PROGRAMMER:      David Welch (welch@mcmail.com)
   6  */
   7
   8 /* INCLUDES *****************************************************************/
   9
  10 #include <rtl.h>
  11
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 #undef RtlUlonglongByteSwap
  16 #undef RtlUlongByteSwap
  17 #undef RtlUshortByteSwap
  18
  19 /* FUNCTIONS *****************************************************************/
  20
  21 /******************************************************************************
  22  *  RtlCompareMemory   [NTDLL.@]
  23  *
  24  * Compare one block of memory with another
  25  *
  26  * PARAMS
  27  *  Source1 [I] Source block
  28  *  Source2 [I] Block to compare to Source1
  29  *  Length  [I] Number of bytes to fill
  30  *
  31  * RETURNS
  32  *  The length of the first byte at which Source1 and Source2 differ, or Length
  33  *  if they are the same.
  34  *
  35  * @implemented
  36  */
  37 SIZE_T NTAPI
  38 RtlCompareMemory(IN const VOID *Source1,
  39                  IN const VOID *Source2,
  40                  IN SIZE_T Length)
  41 {
  42    SIZE_T i;
  43    for(i=0; (i<Length) && (((PUCHAR)Source1)[i]==((PUCHAR)Source2)[i]); i++)
  44       ;
  45    return i;
  46 }
  47
  48
  49 /*
  50  * @implemented
  51  */
  52 ULONG
  53 NTAPI
  54 RtlCompareMemoryUlong (
  55    PVOID Source,
  56    ULONG Length,
  57    ULONG Value
  58 )
  59 /*
  60  * FUNCTION: Compares a block of ULONGs with an ULONG and returns the number of equal bytes
  61  * ARGUMENTS:
  62  *      Source = Block to compare
  63  *      Length = Number of bytes to compare
  64  *      Value = Value to compare
  65  * RETURNS: Number of equal bytes
  66  */
  67 {
  68    PULONG ptr = (PULONG)Source;
  69    ULONG  len = Length / sizeof(ULONG);
  70    ULONG i;
  71
  72    for (i = 0; i < len; i++)
  73    {
  74       if (*ptr != Value)
  75          break;
  76       ptr++;
  77    }
  78
  79    return (ULONG)((PCHAR)ptr - (PCHAR)Source);
  80 }
  81
  82
  83 #undef RtlFillMemory
  84 /*
  85  * @implemented
  86  */
  87 VOID
  88 NTAPI
  89 RtlFillMemory (
  90    PVOID Destination,
  91    ULONG Length,
  92    UCHAR Fill
  93 )
  94 {
  95    memset(Destination, Fill, Length);
  96 }
  97
  98
  99
 100 /*
 101  * @implemented
 102  */
 103 VOID
 104 NTAPI
 105 RtlFillMemoryUlong (
 106    PVOID Destination,
 107    ULONG Length,
 108    ULONG Fill
 109 )
 110 {
 111    PULONG Dest  = Destination;
 112    ULONG  Count = Length / sizeof(ULONG);
 113
 114    while (Count > 0)
 115    {
 116       *Dest = Fill;
 117       Dest++;
 118       Count--;
 119    }
 120 }
 121
 122
 123 #undef RtlMoveMemory
 124 /*
 125  * @implemented
 126  */
 127 VOID
 128 NTAPI
 129 RtlMoveMemory (
 130    PVOID    Destination,
 131    CONST VOID  * Source,
 132    ULONG    Length
 133 )
 134 {
 135    memmove (
 136       Destination,
 137       Source,
 138       Length
 139    );
 140 }
 141
 142 /*
 143 * @implemented
 144 */
 145 VOID
 146 FASTCALL
 147 RtlPrefetchMemoryNonTemporal(
 148         IN PVOID Source,
 149         IN SIZE_T Length
 150         )
 151 {
 152         /* By nature of prefetch, this is non-portable. */
 153         (void)Source;
 154         (void)Length;
 155 }
 156
 157
 158 #undef RtlZeroMemory
 159 /*
 160  * @implemented
 161  */
 162 VOID
 163 NTAPI
 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 */