added stuff

This commit is contained in:
2026-01-04 11:38:45 +03:00
parent 77adc0ea8a
commit 525b273a84
3 changed files with 197 additions and 1 deletions

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@@ -0,0 +1,176 @@
//
// Created by Vladislav on 04.01.2026.
//
#pragma once
#include <array>
#include <cstddef>
#include <cstdint>
#include <span>
#ifdef _MSC_VER
#define OMATH_FORCEINLINE __forceinline
#else
#define OMATH_FORCEINLINE __attribute__((always_inline)) inline
#endif
namespace omath
{
template<class T>
class Anchor;
consteval std::uint64_t fnv1a_64(const char* s)
{
std::uint64_t h = 14695981039346656037ull;
while (*s)
{
h ^= static_cast<unsigned char>(*s++);
h *= 1099511628211ull;
}
return h;
}
// SplitMix64 mixer (good quality for seeding / scrambling)
consteval std::uint64_t splitmix64(std::uint64_t x)
{
x += 0x9E3779B97F4A7C15ull;
x = (x ^ (x >> 30)) * 0xBF58476D1CE4E5B9ull;
x = (x ^ (x >> 27)) * 0x94D049BB133111EBull;
return x ^ (x >> 31);
}
// Choose your policy:
// - If you want reproducible builds, REMOVE __DATE__/__TIME__.
// - If you want "different each build", keep them.
consteval std::uint64_t base_seed()
{
std::uint64_t h = 0;
h ^= fnv1a_64(__FILE__);
h ^= splitmix64(fnv1a_64(__DATE__));
h ^= splitmix64(fnv1a_64(__TIME__));
return splitmix64(h);
}
// Produce a "random" 64-bit value for a given stream index (compile-time)
template<std::uint64_t Stream>
consteval std::uint64_t rand_u64()
{
// Stream is usually __COUNTER__ so each call site differs
return splitmix64(base_seed() + 0xD1B54A32D192ED03ull * (Stream + 1));
}
// Unbiased bounded uniform using Lemire's method (uses 128-bit multiply)
consteval std::uint64_t bounded_u64(std::uint64_t x, std::uint64_t bound)
{
// bound must be > 0
__uint128_t m = static_cast<__uint128_t>(x) * static_cast<__uint128_t>(bound);
return static_cast<std::uint64_t>(m >> 64);
}
template<std::int64_t Lo, std::int64_t Hi, std::uint64_t Stream>
consteval std::int64_t rand_uint8t()
{
static_assert(Lo <= Hi);
const std::uint64_t span = static_cast<std::uint64_t>(Hi - Lo) + 1ull;
const std::uint64_t r = rand_u64<Stream>();
return static_cast<std::int64_t>(bounded_u64(r, span)) + Lo;
}
consteval std::uint64_t rand_u64(std::uint64_t seed, std::uint64_t i)
{
return splitmix64(seed + 0xD1B54A32D192ED03ull * (i + 1ull));
}
// Convert to int (uses low 32 bits; you can also use high bits if you prefer)
consteval std::uint8_t rand_uint8t(std::uint64_t seed, std::uint64_t i)
{
return static_cast<std::uint8_t>(rand_u64(seed, i)); // narrowing is fine/deterministic
}
constexpr std::array<std::uint8_t, 6> create_key()
{
std::array<std::uint8_t, 6> key{};
for (auto& byte : key)
{
byte = static_cast<std::uint8_t>(rand_u64<__COUNTER__>());
}
return key;
}
template<std::size_t N, std::uint64_t Seed, std::size_t... I>
consteval std::array<std::uint8_t, N> make_array_impl(std::index_sequence<I...>)
{
return {rand_uint8t(Seed, static_cast<std::uint64_t>(I))...};
}
template<std::size_t N, std::uint64_t Seed>
consteval std::array<std::uint8_t, N> make_array()
{
return make_array_impl<N, Seed>(std::make_index_sequence<N>{});
}
template<class T, std::size_t key_size, std::array<std::uint8_t, key_size> key>
class EncryptedVariable final
{
bool m_is_encrypted{};
T m_data;
public:
OMATH_FORCEINLINE constexpr explicit EncryptedVariable(const T& data): m_is_encrypted(true), m_data(data)
{
encrypt();
}
[[nodiscard]] constexpr bool is_encrypted() const
{
return m_is_encrypted;
}
OMATH_FORCEINLINE constexpr void decrypt()
{
std::span bytes{reinterpret_cast<std::uint8_t*>(&m_data), sizeof(m_data)};
for (auto& byte : bytes)
for (const auto key_byte : key)
byte ^= key_byte;
m_is_encrypted = false;
}
OMATH_FORCEINLINE constexpr void encrypt()
{
std::span bytes{reinterpret_cast<std::uint8_t*>(&m_data), sizeof(m_data)};
for (auto& byte : bytes)
for (const auto key_byte : key)
byte ^= key_byte;
m_is_encrypted = true;
}
OMATH_FORCEINLINE constexpr T& value()
{
return m_data;
}
OMATH_FORCEINLINE constexpr const T& value() const
{
return m_data;
}
OMATH_FORCEINLINE ~EncryptedVariable()
{
decrypt();
}
};
template<class EncryptedVarType>
class Anchor
{
public:
OMATH_FORCEINLINE constexpr Anchor(EncryptedVarType& var): m_var(var)
{
m_var.decrypt();
}
OMATH_FORCEINLINE constexpr ~Anchor()
{
m_var.encrypt();
}
private:
EncryptedVarType& m_var;
};
} // namespace omath
#define CT_RAND_ARRAY_INT(N) \
(::omath::make_array<(N), (::omath::base_seed() ^ static_cast<std::uint64_t>(__COUNTER__))>())
#define OMATH_DEF_CRYPT_VAR(TYPE, KEY_SIZE) omath::EncryptedVariable<TYPE, KEY_SIZE, CT_RAND_ARRAY_INT(KEY_SIZE)>

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@@ -20,7 +20,7 @@ else() # GTest is being linked as vcpkg package
find_package(GTest CONFIG REQUIRED) find_package(GTest CONFIG REQUIRED)
target_link_libraries(${PROJECT_NAME} PRIVATE GTest::gtest GTest::gtest_main omath::omath) target_link_libraries(${PROJECT_NAME} PRIVATE GTest::gtest GTest::gtest_main omath::omath)
endif() endif()
target_compile_options(${PROJECT_NAME} PRIVATE -static)
if(OMATH_ENABLE_COVERAGE) if(OMATH_ENABLE_COVERAGE)
include(${CMAKE_SOURCE_DIR}/cmake/Coverage.cmake) include(${CMAKE_SOURCE_DIR}/cmake/Coverage.cmake)
omath_setup_coverage(${PROJECT_NAME}) omath_setup_coverage(${PROJECT_NAME})

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//
// Created by Vladislav on 04.01.2026.
//
#include "omath/linear_algebra/vector3.hpp"
#include <gtest/gtest.h>
#include <omath/containers/encrypted_variable.hpp>
TEST(Enc, Test)
{
OMATH_DEF_CRYPT_VAR(omath::Vector3<float>, 128) var{{1.f, 2.f, 3.f}};
OMATH_DEF_CRYPT_VAR(omath::Vector3<float>, 128) var2{{1.f, 2.f, 3.f}};
{
omath::Anchor _ = {var};
omath::Anchor __ = {var2};
std::println("Decrypted var1: {}", var.value());
std::println("Decrypted var2: {}", var2.value());
}
std::println("Encrypted var1: {}", var.value());
std::println("Encrypted var2: {}", var2.value());
}