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      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 }
     41