Merge branch 'master' into dgit/siddebian/2.4.0-ah-1archive/debian/2.4.0-ah-1

1 files changed, 51 insertions, 0 deletions

diff --git a/src/seed.hpp b/src/seed.hpp
new file mode 100644
index 00000000..91ec7eba
--- /dev/null
+++ b/src/seed.hpp
@@ -0,0 +1,51 @@
+#pragma once
+
+#include <array>
+#include <cstdint>
+
+class seed_t {
+
+public:
+	// Number of seed bytes.
+	static constexpr std::size_t n_bytes = 64;
+
+	// Sanity check; we're relying on converting to uint32_t elsewhere,
+	// so let's just keep it as easy as possible.
+	static_assert(n_bytes % 4 == 0, "n_bytes must be multiple of 4");
+
+	// Number of uint32_t's required to store the seed.
+	static constexpr std::size_t n_uint32 = n_bytes / 4;
+
+private:
+	std::array<std::uint8_t, n_bytes> m_data;
+
+	// Default constructor is private. Use the static
+	// factory functions instead.
+	seed_t()
+	{
+		// Factory functions do explicit initialization.
+	};
+
+public:
+
+	/**
+	 * Create a seed from system entropy.
+	 */
+	static seed_t system();
+
+	/**
+	 * Create a seed from the given bytes.
+	 */
+	static seed_t from_bytes(std::uint8_t bytes[n_bytes]);
+
+	/**
+	 * Convert seed to bytes.
+	 */
+	void to_bytes(std::uint8_t bytes[n_bytes]) const;
+
+	/**
+	 * Convert seed to uint32_t's suitable for seed_seq.
+	 */
+	void to_uint32(std::uint32_t seed_seq_data[n_uint32]) const;
+
+};