1 files changed, 104 insertions, 0 deletions
diff --git a/modules/codec/c++/base64.hpp b/modules/codec/c++/base64.hpp
new file mode 100644
index 0000000..fcd2f75
--- /dev/null
+++ b/modules/codec/c++/base64.hpp
@@ -0,0 +1,104 @@
+#pragma once
+
+namespace saw {
+namespace encode {
+struct Base64 {};
+}
+
+template<>
+class data<schema::String, encode::Base64, storage::Default> {
+public:
+	using Schema = schema::String;
+private:
+	std::string data_;
+public:
+	data() = default;
+
+	data(std::string data__):
+		data_{std::move(data__)}
+	{}
+
+	uint64_t size() const {
+		return data_.size();
+	}
+
+	char& at(uint64_t i){
+		return data_.at(i);
+	}
+
+	const char& at(uint64_t i) const {
+		return data_.at(i);
+	}
+
+	bool operator==(const data<Schema, encode::Base64>& rhs) const {
+		return data_ == rhs.data_;
+	}
+};
+
+namespace impl {
+constexpr char base64_char_map[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+}
+
+template<>
+class codec<schema::String, encode::Base64> {
+public:
+	using Schema = schema::String;
+private:
+public:
+	template<typename FromEncode>
+	static error_or<void> encode(const data<Schema, FromEncode>& from, data<Schema,encode::Base64>& to){
+		std::string b64_str;
+
+		try {
+			uint64_t unpadded_len = (from.size() * 4u + 2u) / 3u;
+			uint64_t padded_len = ( unpadded_len + 3u ) & ~3u;
+			b64_str.resize(padded_len);
+		}catch(const std::exception&){
+			return make_error<err::out_of_memory>();
+		}
+
+		uint64_t j{0u}, k{0u};
+		std::array<uint8_t,3> s{};
+
+		for(uint64_t i = 0u; i < from.size(); ++i){
+			s[j] = from.at(i);
+			++j;
+			if(j==3){
+				b64_str.at(k) = impl::base64_char_map[(s[0u] & 0xFC) >> 2];
+				b64_str.at(k+1u) = impl::base64_char_map[((s[0u] & 0x03) << 4) | ((s[1] & 0xF0) >> 4)];
+				b64_str.at(k+2u) = impl::base64_char_map[((s[1u] & 0x0F) << 2) | ((s[2] & 0xC0) >> 6)];
+				b64_str.at(k+3u) = impl::base64_char_map[(s[2u] & 0x3F)];
+				j = 0u;
+				k+=4u;
+			}
+		}
+
+		if(j > 0){
+			if( j == 1u ){
+				s[1u] = 0u;
+			}
+
+			b64_str.at(k+0u) = impl::base64_char_map[(s[0u] & 0xFF) >> 2];
+			b64_str.at(k+1u) = impl::base64_char_map[((s[0u] & 0x03)<<4) + ((s[1u]&0xF0)>>4)];
+			if(j == 2u){
+				b64_str[k+2u] = impl::base64_char_map[ ((s[1u]&0x0F)<<2) ];
+			}else {
+				b64_str[k+2u] = '=';
+			}
+			b64_str[k+3u] = '=';
+		}
+
+		to = {std::move(b64_str)};
+		return void_t{};
+	}
+
+	template<typename ToDecode>
+	static error_or<void> decode(data<Schema,encode::Base64>& from, data<Schema, ToDecode>& to){
+		(void) to;
+		(void) from;
+
+		return make_error<err::not_implemented>();
+	}
+
+};
+}