Starts trying to deal with creating a whole volume from merely a partition.

Storage/MassStorage/Encodings/MacintoshVolume.cpp

@@ -0,0 +1,64 @@
+//
+//  MacintoshVolume.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 25/08/2019.
+//  Copyright © 2019 Thomas Harte. All rights reserved.
+//
+
+#include "MacintoshVolume.hpp"
+
+using namespace Storage::MassStorage::Encodings::Macintosh;
+
+void Mapper::set_drive_type(DriveType drive_type, size_t number_of_blocks) {
+	drive_type_ = drive_type;
+	number_of_blocks_ = number_of_blocks;
+}
+
+size_t Mapper::get_number_of_blocks() {
+	return number_of_blocks_ + 5;
+}
+
+ssize_t Mapper::to_source_address(size_t address) {
+	/*
+		Reserve one block at the start of the device
+		for a partition map.
+
+		TODO: and four or so more for a driver?
+	*/
+	return ssize_t(address) - 5;
+}
+
+std::vector<uint8_t> Mapper::convert_source_block(ssize_t source_address, std::vector<uint8_t> source_data) {
+	switch(source_address) {
+		case -5: {
+			uint32_t total_device_blocks = uint32_t(number_of_blocks_ + 5);
+
+			/* The driver descriptor. */
+			std::vector<uint8_t> driver_description = {
+				0x45, 0x52,		/* device signature */
+				0x02, 0x00,		/* block size, in bytes */
+
+				uint8_t(total_device_blocks >> 24),
+				uint8_t(total_device_blocks >> 16),
+				uint8_t(total_device_blocks >> 8),
+				uint8_t(total_device_blocks),
+								/* number of blocks on device */
+
+				0x00, 0x00,		/* reserved */
+				0x00, 0x00,		/* reserved */
+				0x00, 0x00,		/* reserved */
+
+				0x00, 0x01,		/* number of device descriptor entries */
+				0x00, 0x01,		/* first device descriptor's starting block */
+				0x00, 0x04,		/* size of device driver */
+				0x00, 0x01,		/* operating system (MacOS = 1) */
+			};
+			driver_description.resize(512);
+
+			return driver_description;
+		}
+
+		default: return source_data;
+	}
+}