From 1cd0b619ef5290807608b5eda11fa535fc7dcaea Mon Sep 17 00:00:00 2001
From: Imbus <>
Date: Wed, 12 Feb 2025 19:47:19 +0100
Subject: [PATCH] Psuedo random number gen

---
 rand.c | 22 ++++++++++++++++++++++
 rand.h | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)
 create mode 100644 rand.c
 create mode 100644 rand.h

diff --git a/rand.c b/rand.c
new file mode 100644
index 0000000..74cb7ad
--- /dev/null
+++ b/rand.c
@@ -0,0 +1,22 @@
+#include <stdint.h>
+
+#include <stdint.h>
+
+#define BUILD_SEED ((uint64_t)(__TIME__[0]) * (uint64_t)(__TIME__[1]) * \
+                    (uint64_t)(__TIME__[3]) * (uint64_t)(__TIME__[4]) * \
+                    (uint64_t)(__TIME__[6]) * (uint64_t)(__TIME__[7]))
+
+static uint64_t seed = BUILD_SEED;
+
+void sprand(uint64_t s) {
+    seed = s ? s : 1; // Ensure the seed is never 0
+}
+
+uint64_t prand() {
+    seed = seed * 6364136223846793005ULL + 1;
+    return seed;
+}
+
+uint64_t prand_range(uint64_t min, uint64_t max) {
+    return min + (prand() % (max - min + 1));
+}
diff --git a/rand.h b/rand.h
new file mode 100644
index 0000000..3722734
--- /dev/null
+++ b/rand.h
@@ -0,0 +1,34 @@
+#pragma once
+#include <stdint.h>
+
+/**
+ * @brief Sets the seed for the custom random number generator.
+ *
+ * This function initializes the seed value used by rand_custom().
+ * Providing the same seed will produce the same sequence of random numbers.
+ *
+ * @param s The seed value (must be nonzero for best results).
+ */
+void sprand(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 prand();
+
+/**
+ * @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 prand_range(uint64_t min, uint64_t max);