com32/lib/lrand48.c

   1 /*
   2  * lrand48.c
   3  */
   4
   5 #include <stdlib.h>
   6 #include <stdint.h>
   7
   8 unsigned short __rand48_seed[3];
   9
  10 long jrand48(unsigned short xsubi[3])
  11 {
  12     uint64_t x;
  13
  14     /* The xsubi[] array is littleendian by spec */
  15     x = (uint64_t) xsubi[0] +
  16         ((uint64_t) xsubi[1] << 16) + ((uint64_t) xsubi[2] << 32);
  17
  18     x = (0x5deece66dULL * x) + 0xb;
  19
  20     xsubi[0] = (unsigned short)x;
  21     xsubi[1] = (unsigned short)(x >> 16);
  22     xsubi[2] = (unsigned short)(x >> 32);
  23
  24     return (long)(int32_t) (x >> 16);
  25 }
  26
  27 long mrand48(void)
  28 {
  29     return jrand48(__rand48_seed);
  30 }
  31
  32 long nrand48(unsigned short xsubi[3])
  33 {
  34     return (long)((uint32_t) jrand48(xsubi) >> 1);
  35 }
  36
  37 long lrand48(void)
  38 {
  39     return (long)((uint32_t) mrand48() >> 1);
  40 }