Adds support for Macintosh SCSI device images.

This is now in addition to the single-partition images previously supported.

Storage/MassStorage/Formats/DSK.cpp

@@ -0,0 +1,23 @@
+//
+//  DSK.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 01/05/2021.
+//  Copyright © 2021 Thomas Harte. All rights reserved.
+//
+
+#include "DSK.hpp"
+
+using namespace Storage::MassStorage;
+
+DSK::DSK(const std::string &file_name) : RawSectorDump(file_name) {
+	// Minimum validation: check the first sector for a device signature,
+	// with 512-byte blocks.
+	const auto sector = get_block(0);
+	if(sector.size() != 512) {
+		throw std::exception();
+	}
+	if(sector[0] != 0x45 || sector[1] != 0x52 || sector[2] != 0x02 || sector[3] != 0x00) {
+		throw std::exception();
+	}
+}

Storage/MassStorage/Formats/DSK.hpp

@@ -0,0 +1,30 @@
+//
+//  DSK.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 01/05/2021.
+//  Copyright © 2021 Thomas Harte. All rights reserved.
+//
+
+#ifndef MassStorage_DSK_hpp
+#define MassStorage_DSK_hpp
+
+#include "RawSectorDump.hpp"
+
+namespace Storage {
+namespace MassStorage {
+
+/*!
+	Provides a @c MassStorageDevice containing a Macintosh DSK image, which is just a
+	sector dump of an entire HFS drive. It will be validated for an Apple-style partition map and communicate
+	in 512-byte blocks.
+*/
+class DSK: public RawSectorDump<512> {
+	public:
+		DSK(const std::string &file_name);
+};
+
+}
+}
+
+#endif /* MassStorage_DSK_hpp */

Storage/MassStorage/Formats/HFV.cpp

@@ -15,7 +15,10 @@ HFV::HFV(const std::string &file_name) : file_(file_name) {
 	const auto file_size = file_.stats().st_size;
 	if(file_size & 511 || file_size <= 800*1024) throw std::exception();
 
-	// TODO: check filing system for MFS, HFS or HFS+.
+	// Is this an HFS volume?
+	// TODO: check filing system for MFS or HFS+.
+	const auto prefix = file_.read(2);
+	if(prefix[0] != 'L' || prefix[1] != 'K')  throw std::exception();
 }
 
 size_t HFV::get_block_size() {

Storage/MassStorage/SCSI/DirectAccessDevice.cpp

@@ -19,7 +19,7 @@ bool DirectAccessDevice::read(const Target::CommandState &state, Target::Respond
 	if(!device_) return false;
 
 	const auto specs = state.read_write_specs();
-	LOG("Read: " << specs.number_of_blocks << " from " << specs.address);
+	LOG("Read: " << std::dec << specs.number_of_blocks << " from " << specs.address);
 
 	std::vector<uint8_t> output = device_->get_block(specs.address);
 	for(uint32_t offset = 1; offset < specs.number_of_blocks; ++offset) {