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#include <stdint.h>
#include <stdlib.h>
/*
* Finds a pseudorandom 32-bit number from 0 to 2^32-1 .
* Uses the BCPL linear congruential generator method.
*
* Used instead of system RNG to ensure tests are consistent.
*/
static uint32_t rand32(void)
{
#if 0
/*
* Tests should be run with a different random function
* from time to time. I've found that the method below
* sometimes behaves poorly for testing purposes.
* For example, rand32() % N might only return even numbers.
*/
assert(RAND_MAX == 2147483647);
return ((random() & 0xFFFF) << 16) | (random() & 0xFFFF);
#else
static uint32_t rand32_state = 0;
rand32_state *= (uint32_t)0x7FF8A3ED;
rand32_state += (uint32_t)0x2AA01D31;
return rand32_state;
#endif
}
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