diff -r 807f8543d10e -r 368ba99bb98f src/FreeformASN1ContentHandler.h
--- a/src/FreeformASN1ContentHandler.h	Sun Jul 25 12:09:30 2021 +0200
+++ b/src/FreeformASN1ContentHandler.h	Sun Jul 25 18:22:07 2021 +0200
@@ -26,8 +26,16 @@
 namespace in {
 namespace asn1 {
 
+/**
+ * Converts arbitrary ASN.1 stream of events to a relation
+ * i.e. does not require any specific structures/schema.
+ *
+ * Useful especially for testing and debugging and sometimes instead of relpipe-in-asn1table,
+ * because this handler supports streaming and does not depend on any third-party library (no XML dependency).
+ */
 class FreeformASN1ContentHandler : public lib::ASN1ContentHandler {
 private:
+	wstring_convert < codecvt_utf8<wchar_t>> convertor; // ASN.1 parser works with UTF-8
 	std::shared_ptr<relpipe::writer::RelationalWriter> writer;
 	Configuration configuration;
 	std::vector<relpipe::common::type::Integer> position;
@@ -38,6 +46,8 @@
 		const std::vector<relpipe::common::type::Integer>& position;
 		relpipe::common::type::Integer level = 0;
 		relpipe::common::type::StringX event;
+		relpipe::common::type::StringX valueText;
+		relpipe::common::type::StringX valueBinary;
 
 		Record(const Header* header, std::vector<relpipe::common::type::Integer>& position, relpipe::common::type::StringX event) : header(header), position(position), event(event) {
 		}
@@ -74,6 +84,19 @@
 		// writer->writeAttribute(&pc, typeid (pc));
 		writer->writeAttribute(&tagClass, typeid (tagClass));
 		writer->writeAttribute(&tag, typeid (tag));
+		writer->writeAttribute(&r.valueText, typeid (r.valueText));
+		writer->writeAttribute(&r.valueBinary, typeid (r.valueBinary));
+	}
+
+	/**
+	 * @param header
+	 * @param value an octet string
+	 * @return original value if octet string was a text string; otherwise an empty string
+	 */
+	const std::string getText(const Header& header, const std::string& value) {
+		// TODO: support also UTF-8
+		for (uint8_t b : value) if (b < 32 || b >= 127) return "";
+		return value;
 	}
 
 public:
@@ -94,6 +117,8 @@
 			// {L"pc", relpipe::writer::TypeId::STRING},
 			{L"tag_class", relpipe::writer::TypeId::STRING},
 			{L"tag", relpipe::writer::TypeId::INTEGER},
+			{L"value_text", relpipe::writer::TypeId::STRING},
+			{L"value_binary", relpipe::writer::TypeId::STRING}, // TODO: OctetString data type (when available) instead of text
 		}, true);
 
 		position.push_back(-1); // TODO: null
@@ -107,6 +132,7 @@
 		auto id = position.back() + 1;
 		position.pop_back();
 		position.back() = id;
+		// TODO: put end event under the start parent?
 		Record r(nullptr, position, L"stream-end");
 		write(r);
 	}
@@ -122,61 +148,91 @@
 		auto id = position.back() + 1;
 		position.pop_back();
 		position.back() = id;
+		// TODO: put end event under the start parent?
 		Record r(nullptr, position, L"collection-end");
 		write(r);
 	}
 
 	void writeBitString(const Header& header, std::vector<bool> value) override {
+		std::stringstream bits;
+		for (bool b : value) bits << (int) b;
+		// for (bool b : value) bits << (b ? ':' : '.'); // TODO: configurable true/false symbols?
+
 		position.back()++;
 		Record r(&header, position, L"bit-string");
+		r.valueText = convertor.from_bytes(bits.str());
 		write(r);
 	}
 
 	void writeBoolean(const Header& header, bool value) override {
 		position.back()++;
 		Record r(&header, position, L"boolean");
+		r.valueText = value ? L"true" : L"false";
+		r.valueBinary = value ? L"FF" : L"00";
 		write(r);
 	}
 
 	void writeDateTime(const Header& header, DateTime value) override {
 		position.back()++;
 		Record r(&header, position, L"date-time");
+		r.valueText = convertor.from_bytes(value.toString());
 		write(r);
 	}
 
 	void writeInteger(const Header& header, Integer value) override {
 		position.back()++;
 		Record r(&header, position, L"integer");
+		r.valueText = convertor.from_bytes(value.toString());
+		r.valueBinary = convertor.from_bytes(value.toHex());
 		write(r);
 	}
 
 	void writeNull(const Header& header) override {
 		position.back()++;
 		Record r(&header, position, L"null");
+		r.valueText = L"null";
 		write(r);
 	}
 
 	void writeOID(const Header& header, ObjectIdentifier value) override {
 		position.back()++;
 		Record r(&header, position, L"oid");
+		r.valueText = convertor.from_bytes(value.toString());
 		write(r);
 	}
 
 	void writeOctetString(const Header& header, std::string value) override {
+		std::string text = getText(header, value);
+		std::stringstream hex;
+		hex << std::hex << std::setfill('0');
+		for (uint8_t b : value) hex << std::setw(2) << (int) b;
+
 		position.back()++;
 		Record r(&header, position, L"octet-string");
+		r.valueText = convertor.from_bytes(text);
+		r.valueBinary = convertor.from_bytes(hex.str());
 		write(r);
 	}
 
 	void writeTextString(const Header& header, std::string value) override {
 		position.back()++;
 		Record r(&header, position, L"text-string");
+		r.valueText = convertor.from_bytes(value);
 		write(r);
 	}
 
 	void writeSpecific(const Header& header, std::string value) override {
+		std::stringstream hex;
+		hex << std::hex << std::setfill('0');
+		for (uint8_t b : value) hex << std::setw(2) << (int) b;
+
+		std::stringstream ascii;
+		for (uint8_t b : value) ascii << (b >= 32 && b < 127 ? (char) b : '.'); // TODO: configurable unsupported symbol?
+
 		position.back()++;
 		Record r(&header, position, L"specific");
+		r.valueText = convertor.from_bytes(ascii.str());
+		r.valueBinary = convertor.from_bytes(hex.str());
 		write(r);
 	}