Introduces a container for ZX Spectrum-style TAPs.

Storage/Tape/Formats/ZXSpectrumTAP.cpp

@@ -0,0 +1,47 @@
+//
+//  SpectrumTAP.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 19/03/2021.
+//  Copyright © 2021 Thomas Harte. All rights reserved.
+//
+
+#include "ZXSpectrumTAP.hpp"
+
+using namespace Storage::Tape;
+
+ZXSpectrumTAP::ZXSpectrumTAP(const std::string &file_name) :
+	file_(file_name)
+{
+	// Check for a continuous series of blocks through to
+	// file end, alternating header and data.
+	uint8_t next_block_type = 0x00;
+	while(true) {
+		const uint16_t block_length = file_.get16le();
+		const uint8_t block_type = file_.get8();
+		if(file_.eof()) throw ErrorNotZXSpectrumTAP;
+
+		if(block_type != next_block_type) {
+			throw ErrorNotZXSpectrumTAP;
+		}
+		next_block_type ^= 0xff;
+
+		file_.seek(block_length - 1, SEEK_CUR);
+		if(file_.tell() == file_.stats().st_size) break;
+	}
+
+	virtual_reset();
+}
+
+bool ZXSpectrumTAP::is_at_end() {
+	return false;
+}
+
+void ZXSpectrumTAP::virtual_reset() {
+	file_.seek(0, SEEK_SET);
+	block_length_ = file_.get16le();
+}
+
+Tape::Pulse ZXSpectrumTAP::virtual_get_next_pulse() {
+	return Pulse();
+}

Storage/Tape/Formats/ZXSpectrumTAP.hpp

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+//
+//  SpectrumTAP.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 19/03/2021.
+//  Copyright © 2021 Thomas Harte. All rights reserved.
+//
+
+#ifndef SpectrumTAP_hpp
+#define SpectrumTAP_hpp
+
+#include "../Tape.hpp"
+#include "../../FileHolder.hpp"
+
+#include <cstdint>
+#include <string>
+
+namespace Storage {
+namespace Tape {
+
+/*!
+	Provides a @c Tape containing an Spectrum-format tape image, which contains a series of
+	header and data blocks.
+*/
+class ZXSpectrumTAP: public Tape {
+	public:
+		/*!
+			Constructs a @c ZXSpectrumTAP containing content from the file with name @c file_name.
+
+			@throws ErrorNotZXSpectrumTAP if this file could not be opened and recognised as a valid Spectrum-format TAP.
+		*/
+		ZXSpectrumTAP(const std::string &file_name);
+
+		enum {
+			ErrorNotZXSpectrumTAP
+		};
+
+	private:
+		Storage::FileHolder file_;
+
+		uint16_t block_length_ = 0;
+
+		// Implemented to satisfy @c Tape.
+		bool is_at_end() override;
+		void virtual_reset() override;
+		Pulse virtual_get_next_pulse() override;
+};
+
+
+}
+}
+
+#endif /* SpectrumTAP_hpp */