Badrand pseudo random number generator, emphasis on pseudo

kern/libkern/badrand.h

@@ -0,0 +1,43 @@
+#ifndef BADRAND_H
+#define BADRAND_H
+
+#include <stdint.h>
+
+/*
+ * This is a PRNG for non-cryptographic use.
+ *
+ * See:
+ *      https://en.wikipedia.org/wiki/Linear_congruential_generator
+ */
+
+/**
+ * @brief Sets the seed for the PRNG.
+ *
+ * @param s The specific seed value or zero. If zero is passed, it will call
+ * rand_reseed().
+ */
+void sbadrand(uint64_t s);
+
+/**
+ * @brief Generates a pseudo-random 64-bit number.
+ *
+ * Uses a simple Linear Congruential Generator (LCG) to produce
+ * a sequence of pseudo-random numbers.
+ *
+ * @return A pseudo-random 64-bit unsigned integer.
+ */
+uint64_t badrand();
+
+/**
+ * @brief Generates a random number within a specified range.
+ *
+ * Produces a random number in the inclusive range [min, max].
+ * Ensures uniform distribution by applying a modulo operation.
+ *
+ * @param min The lower bound of the range (inclusive).
+ * @param max The upper bound of the range (inclusive).
+ * @return A random number between min and max.
+ */
+uint64_t badrand_range(uint64_t min, uint64_t max);
+
+#endif // BADRAND_H