Initial commit

arm9/source/rng/LinearCongruentialGenerator.cpp

@@ -0,0 +1,8 @@
+#include "common.h"
+#include "LinearCongruentialGenerator.h"
+
+u32 LinearCongruentialGenerator::Next()
+{
+    _state = _state * 0x5D588B656C078965LL + 0x269EC3LL;
+    return _state >> 32;
+}

arm9/source/rng/LinearCongruentialGenerator.h

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+#pragma once
+#include "RandomGenerator.h"
+
+class LinearCongruentialGenerator : public RandomGenerator
+{
+public:
+    explicit LinearCongruentialGenerator(u64 seed)
+        : _state(seed) { }
+
+    void Seed(u64 seed) override
+    {
+        _state = seed;
+    }
+
+protected:
+    u32 Next() override;
+
+private:
+    u64 _state;
+};

arm9/source/rng/RandomGenerator.h

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+#pragma once
+#include "common.h"
+
+class RandomGenerator
+{
+    template<class> friend class ThreadSafeRandomGenerator;
+
+public:
+    virtual void Seed(u64 seed) = 0;
+
+    u32 NextU32()
+    {
+        return Next();
+    }
+
+    u32 NextU32(u32 maxPlusOne)
+    {
+        return ((u64)Next() * maxPlusOne) >> 32;
+    }
+
+    u32 NextU32(u32 min, u32 maxPlusOne)
+    {
+        return NextU32(maxPlusOne - min) + min;
+    }
+
+    s32 NextS32()
+    {
+        return Next();
+    }
+
+    u32 NextS32(s32 min, s32 maxPlusOne)
+    {
+        return NextU32(maxPlusOne - min) + min;
+    }
+
+protected:
+    virtual u32 Next() = 0;
+};

arm9/source/rng/ThreadSafeRandomGenerator.h

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+#pragma once
+#include <memory>
+#include <libtwl/rtos/rtosMutex.h>
+#include "RandomGenerator.h"
+
+template <class TGenerator>
+class ThreadSafeRandomGenerator : public RandomGenerator
+{
+public:
+    template <typename ...Args>
+    explicit ThreadSafeRandomGenerator(Args && ...args)
+        : _generator(std::forward<Args>(args)...)
+    {
+        rtos_createMutex(&_mutex);
+    }
+
+    void Seed(u64 seed) override
+    {
+        rtos_lockMutex(&_mutex);
+        {
+            _generator.Seed(seed);
+        }
+        rtos_unlockMutex(&_mutex);
+    }
+
+protected:
+    u32 Next() override
+    {
+        u32 result;
+        rtos_lockMutex(&_mutex);
+        {
+            result = ((RandomGenerator&)_generator).Next();
+        }
+        rtos_unlockMutex(&_mutex);
+        return result;
+    }
+
+private:
+    rtos_mutex_t _mutex;
+    TGenerator _generator;
+};