src/tint/fuzzers/mersenne_twister_engine.h

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#ifndef SRC_TINT_FUZZERS_MERSENNE_TWISTER_ENGINE_H_
#define SRC_TINT_FUZZERS_MERSENNE_TWISTER_ENGINE_H_

#include <random>

#include "src/tint/fuzzers/random_generator_engine.h"

namespace tint::fuzzers {

/// Standard MT based random number generation
class MersenneTwisterEngine : public RandomGeneratorEngine {
  public:
    /// @brief Initializes using provided seed
    /// @param seed - seed value to use
    explicit MersenneTwisterEngine(uint64_t seed);
    ~MersenneTwisterEngine() override = default;

    /// Generate random uint32_t value from uniform distribution.
    /// @param lower - lower bound of integer generated
    /// @param upper - upper bound of integer generated
    /// @returns i, where lower <= i < upper
    uint32_t RandomUInt32(uint32_t lower, uint32_t upper) override;

    /// Get random uint64_t value from uniform distribution.
    /// @param lower - lower bound of integer generated
    /// @param upper - upper bound of integer generated
    /// @returns i, where lower <= i < upper
    uint64_t RandomUInt64(uint64_t lower, uint64_t upper) override;

    /// Get N bytes of pseudo-random data
    /// @param dest - memory location to store data
    /// @param n - number of bytes of data to generate
    void RandomNBytes(uint8_t* dest, size_t n) override;

  private:
    // Disallow copy & assign
    MersenneTwisterEngine(const MersenneTwisterEngine&) = delete;
    MersenneTwisterEngine& operator=(const MersenneTwisterEngine&) = delete;

    std::mt19937_64 engine_;
};  // class MersenneTwisterEngine

}  // namespace tint::fuzzers

#endif  // SRC_TINT_FUZZERS_MERSENNE_TWISTER_ENGINE_H_