diff -r ee70b17950bd -r 80e129ec3408 src/lib/UnescapingINIHandler.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lib/UnescapingINIHandler.h	Wed Nov 25 21:50:26 2020 +0100
@@ -0,0 +1,99 @@
+/**
+ * Relational pipes
+ * Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <sstream>
+
+#include "INIReader.h"
+
+using namespace std;
+using namespace relpipe::writer;
+
+namespace relpipe {
+namespace in {
+namespace ini {
+namespace lib {
+
+class UnescapingINIContentHandler : public INIContentHandler {
+private:
+	INIContentHandler& output;
+
+protected:
+	const char ESC = '\\';
+	bool lastEscaphingPhase;
+
+	std::stringstream& put(std::stringstream& result, const char& ch, int& i) {
+		result.put(ch);
+		i++;
+		return result;
+	}
+
+	virtual std::string unescape(const std::string& s) = 0;
+
+public:
+
+	/**
+	 * @param output here will be sent events with unescaped values
+	 * @param lastEscaphingPhase instances of UnescapingINIContentHandler might be chained:
+	 * unsupported escaping sequences are kept untouched to be processed in further phases;
+	 * in the last phase, all remaining sequences (including \\) must be recognized and unescaped
+	 * (otherwise the input is considered invalid and an exception is thrown)
+	 */
+	UnescapingINIContentHandler(INIContentHandler& output, bool lastEscaphingPhase) : output(output), lastEscaphingPhase(lastEscaphingPhase) {
+	}
+
+	void startDocument() override {
+		output.startDocument();
+	}
+
+	void endDocument() override {
+		output.endDocument();
+	}
+
+	void startSection(const SectionStartEvent& event) override {
+		SectionStartEvent e = event;
+		e.name = unescape(e.name);
+		output.startSection(e);
+	}
+
+	void endSection() override {
+		output.endSection();
+	}
+
+	void entry(const EntryEvent& event) override {
+		EntryEvent e = event;
+		e.key = unescape(e.key);
+		e.fullKey = unescape(e.fullKey);
+		e.subKey = unescape(e.subKey);
+		e.value = unescape(e.value);
+		output.entry(e);
+	}
+
+	void comment(const CommentEvent& event) override {
+		output.comment(event);
+	}
+
+	void whitespace(const WhitespaceEvent& event) override {
+		output.whitespace(event);
+	}
+
+};
+
+}
+}
+}
+}