Factors out commonalities in SSD/DSD and ADF implementations.

OSBindings/Mac/Clock Signal.xcodeproj/project.pbxproj

@@ -84,6 +84,7 @@
 		4B50730A1DDFCFDF00C48FBD /* ArrayBuilderTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 4B5073091DDFCFDF00C48FBD /* ArrayBuilderTests.mm */; };
 		4B55CE5D1C3B7D6F0093A61B /* CSOpenGLView.m in Sources */ = {isa = PBXBuildFile; fileRef = 4B55CE5C1C3B7D6F0093A61B /* CSOpenGLView.m */; };
 		4B55CE5F1C3B7D960093A61B /* MachineDocument.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4B55CE5E1C3B7D960093A61B /* MachineDocument.swift */; };
+		4B58601E1F806AB200AEE2E3 /* MFMSectorDump.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B58601C1F806AB200AEE2E3 /* MFMSectorDump.cpp */; };
 		4B59199C1DAC6C46005BB85C /* OricTAP.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B59199A1DAC6C46005BB85C /* OricTAP.cpp */; };
 		4B5A12571DD55862007A2231 /* Disassembler6502.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B5A12551DD55862007A2231 /* Disassembler6502.cpp */; };
 		4B5FADBA1DE3151600AEC565 /* FileHolder.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B5FADB81DE3151600AEC565 /* FileHolder.cpp */; };
@@ -631,6 +632,8 @@
 		4B55CE5B1C3B7D6F0093A61B /* CSOpenGLView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = CSOpenGLView.h; sourceTree = "<group>"; };
 		4B55CE5C1C3B7D6F0093A61B /* CSOpenGLView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = CSOpenGLView.m; sourceTree = "<group>"; };
 		4B55CE5E1C3B7D960093A61B /* MachineDocument.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = MachineDocument.swift; sourceTree = "<group>"; };
+		4B58601C1F806AB200AEE2E3 /* MFMSectorDump.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = MFMSectorDump.cpp; sourceTree = "<group>"; };
+		4B58601D1F806AB200AEE2E3 /* MFMSectorDump.hpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = MFMSectorDump.hpp; sourceTree = "<group>"; };
 		4B59199A1DAC6C46005BB85C /* OricTAP.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = OricTAP.cpp; sourceTree = "<group>"; };
 		4B59199B1DAC6C46005BB85C /* OricTAP.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = OricTAP.hpp; sourceTree = "<group>"; };
 		4B5A12551DD55862007A2231 /* Disassembler6502.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Disassembler6502.cpp; path = ../../StaticAnalyser/Disassembler/Disassembler6502.cpp; sourceTree = "<group>"; };
@@ -1472,7 +1475,6 @@
 		4B45188C1F75FD1B00926311 /* Formats */ = {
 			isa = PBXGroup;
 			children = (
-				4BFDD7891F7F2DB4008579B9 /* Utility */,
 				4B45188D1F75FD1B00926311 /* AcornADF.cpp */,
 				4B45188E1F75FD1B00926311 /* AcornADF.hpp */,
 				4B45188F1F75FD1B00926311 /* CPCDSK.cpp */,
@@ -1483,10 +1485,13 @@
 				4B4518941F75FD1B00926311 /* G64.hpp */,
 				4B4518951F75FD1B00926311 /* HFE.cpp */,
 				4B4518961F75FD1B00926311 /* HFE.hpp */,
+				4B58601C1F806AB200AEE2E3 /* MFMSectorDump.cpp */,
+				4B58601D1F806AB200AEE2E3 /* MFMSectorDump.hpp */,
 				4B4518971F75FD1B00926311 /* OricMFMDSK.cpp */,
 				4B4518981F75FD1B00926311 /* OricMFMDSK.hpp */,
 				4B4518991F75FD1B00926311 /* SSD.cpp */,
 				4B45189A1F75FD1B00926311 /* SSD.hpp */,
+				4BFDD7891F7F2DB4008579B9 /* Utility */,
 			);
 			path = Formats;
 			sourceTree = "<group>";
@@ -2463,8 +2468,8 @@
 		4BFDD7891F7F2DB4008579B9 /* Utility */ = {
 			isa = PBXGroup;
 			children = (
-				4BFDD78A1F7F2DB4008579B9 /* ImplicitSectors.hpp */,
 				4BFDD78B1F7F2DB4008579B9 /* ImplicitSectors.cpp */,
+				4BFDD78A1F7F2DB4008579B9 /* ImplicitSectors.hpp */,
 			);
 			path = Utility;
 			sourceTree = "<group>";
@@ -2898,6 +2903,7 @@
 				4B59199C1DAC6C46005BB85C /* OricTAP.cpp in Sources */,
 				4BB697CE1D4BA44400248BDF /* CommodoreGCR.cpp in Sources */,
 				4B7136861F78724F008B8ED9 /* Encoder.cpp in Sources */,
+				4B58601E1F806AB200AEE2E3 /* MFMSectorDump.cpp in Sources */,
 				4B448E841F1C4C480009ABD6 /* PulseQueuedTape.cpp in Sources */,
 				4BD14B111D74627C0088EAD6 /* StaticAnalyser.cpp in Sources */,
 				4BBF99151C8FBA6F0075DAFB /* CRTOpenGL.cpp in Sources */,

Storage/Disk/DiskImage/Formats/AcornADF.cpp

@@ -12,18 +12,16 @@
 
 namespace {
 	static const unsigned int sectors_per_track = 16;
-	static const size_t bytes_per_sector = 256;
 	static const unsigned int sector_size = 1;
 }
 
 using namespace Storage::Disk;
 
-AcornADF::AcornADF(const char *file_name) :
-		Storage::FileHolder(file_name) {
+AcornADF::AcornADF(const char *file_name) : MFMSectorDump(file_name) {
 	// very loose validation: the file needs to be a multiple of 256 bytes
 	// and not ungainly large
-	if(file_stats_.st_size % (off_t)bytes_per_sector) throw ErrorNotAcornADF;
-	if(file_stats_.st_size < 7 * (off_t)bytes_per_sector) throw ErrorNotAcornADF;
+	if(file_stats_.st_size % (off_t)(128 << sector_size)) throw ErrorNotAcornADF;
+	if(file_stats_.st_size < 7 * (off_t)(128 << sector_size)) throw ErrorNotAcornADF;
 
 	// check that the initial directory's 'Hugo's are present
 	fseek(file_, 513, SEEK_SET);
@@ -34,6 +32,8 @@ AcornADF::AcornADF(const char *file_name) :
 	fseek(file_, 0x6fb, SEEK_SET);
 	fread(bytes, 1, 4, file_);
 	if(bytes[0] != 'H' || bytes[1] != 'u' || bytes[2] != 'g' || bytes[3] != 'o') throw ErrorNotAcornADF;
+
+	set_geometry(sectors_per_track, sector_size, true);
 }
 
 unsigned int AcornADF::get_head_position_count() {
@@ -44,37 +44,6 @@ unsigned int AcornADF::get_head_count() {
 	return 1;
 }
 
-bool AcornADF::get_is_read_only() {
-	return is_read_only_;
-}
-
 long AcornADF::get_file_offset_for_position(unsigned int head, unsigned int position) {
-	return (position * 1 + head) * bytes_per_sector * sectors_per_track;
-}
-
-std::shared_ptr<Track> AcornADF::get_track_at_position(unsigned int head, unsigned int position) {
-	uint8_t sectors[bytes_per_sector*sectors_per_track];
-
-	if(head > 1) return nullptr;
-	long file_offset = get_file_offset_for_position(head, position);
-
-	{
-		std::lock_guard<std::mutex> lock_guard(file_access_mutex_);
-		fseek(file_, file_offset, SEEK_SET);
-		fread(sectors, 1, sizeof(sectors), file_);
-	}
-
-	return track_for_sectors(sectors, (uint8_t)position, (uint8_t)head, 0, sector_size, true);
-}
-
-void AcornADF::set_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track) {
-	uint8_t parsed_track[bytes_per_sector*sectors_per_track];
-	decode_sectors(*track, parsed_track, 0, sectors_per_track-1, sector_size, true);
-
-	long file_offset = get_file_offset_for_position(head, position);
-
-	std::lock_guard<std::mutex> lock_guard(file_access_mutex_);
-	ensure_file_is_at_least_length(file_offset);
-	fseek(file_, file_offset, SEEK_SET);
-	fwrite(parsed_track, 1, sizeof(parsed_track), file_);
+	return (position * 1 + head) * (128 << sector_size) * sectors_per_track;
 }

Storage/Disk/DiskImage/Formats/AcornADF.hpp

@@ -9,8 +9,7 @@
 #ifndef AcornADF_hpp
 #define AcornADF_hpp
 
-#include "../DiskImage.hpp"
-#include "../../../FileHolder.hpp"
+#include "MFMSectorDump.hpp"
 
 namespace Storage {
 namespace Disk {
@@ -18,7 +17,7 @@ namespace Disk {
 /*!
 	Provies a @c Disk containing an ADF disk image — a decoded sector dump of an Acorn ADFS disk.
 */
-class AcornADF: public DiskImage, public Storage::FileHolder {
+class AcornADF: public MFMSectorDump {
 	public:
 		/*!
 			Construct an @c AcornADF containing content from the file with name @c file_name.
@@ -34,12 +33,8 @@ class AcornADF: public DiskImage, public Storage::FileHolder {
 
 		unsigned int get_head_position_count();
 		unsigned int get_head_count();
-		bool get_is_read_only();
-		void set_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track);
-		std::shared_ptr<Track> get_track_at_position(unsigned int head, unsigned int position);
 
 	private:
-		std::mutex file_access_mutex_;
 		long get_file_offset_for_position(unsigned int head, unsigned int position);
 };
 

Storage/Disk/DiskImage/Formats/MFMSectorDump.cpp

@@ -0,0 +1,54 @@
+//
+//  MFMSectorDump.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 30/09/2017.
+//  Copyright © 2017 Thomas Harte. All rights reserved.
+//
+
+#include "MFMSectorDump.hpp"
+
+#include "Utility/ImplicitSectors.hpp"
+
+using namespace Storage::Disk;
+
+MFMSectorDump::MFMSectorDump(const char *file_name) : Storage::FileHolder(file_name) {}
+
+void MFMSectorDump::set_geometry(int sectors_per_track, uint8_t sector_size, bool is_double_density) {
+	sectors_per_track_ = sectors_per_track;
+	sector_size_ = sector_size;
+	is_double_density_ = is_double_density;
+}
+
+bool MFMSectorDump::get_is_read_only() {
+	return is_read_only_;
+}
+
+std::shared_ptr<Track> MFMSectorDump::get_track_at_position(unsigned int head, unsigned int position) {
+	uint8_t sectors[(128 << sector_size_)*sectors_per_track_];
+
+	if(head > 1) return nullptr;
+	long file_offset = get_file_offset_for_position(head, position);
+
+	{
+		std::lock_guard<std::mutex> lock_guard(file_access_mutex_);
+		fseek(file_, file_offset, SEEK_SET);
+		fread(sectors, 1, sizeof(sectors), file_);
+	}
+
+	return track_for_sectors(sectors, (uint8_t)position, (uint8_t)head, 0, sector_size_, is_double_density_);
+}
+
+void MFMSectorDump::set_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track) {
+	uint8_t parsed_track[(128 << sector_size_)*sectors_per_track_];
+	// Assumption here: sector IDs will run from 0.
+	decode_sectors(*track, parsed_track, 0, (uint8_t)(sectors_per_track_-1), sector_size_, is_double_density_);
+
+	long file_offset = get_file_offset_for_position(head, position);
+
+	std::lock_guard<std::mutex> lock_guard(file_access_mutex_);
+	ensure_file_is_at_least_length(file_offset);
+	fseek(file_, file_offset, SEEK_SET);
+	fwrite(parsed_track, 1, sizeof(parsed_track), file_);
+	fflush(file_);
+}

Storage/Disk/DiskImage/Formats/MFMSectorDump.hpp

@@ -0,0 +1,42 @@
+//
+//  MFMSectorDump.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 30/09/2017.
+//  Copyright © 2017 Thomas Harte. All rights reserved.
+//
+
+#ifndef SectorDump_hpp
+#define SectorDump_hpp
+
+#include "../DiskImage.hpp"
+#include "../../../FileHolder.hpp"
+
+namespace Storage {
+namespace Disk {
+
+/*!
+	Provies the base for writeable [M]FM disk images that just contain contiguous sector content dumps.
+*/
+class MFMSectorDump: public DiskImage, public Storage::FileHolder {
+	public:
+		MFMSectorDump(const char *file_name);
+		void set_geometry(int sectors_per_track, uint8_t sector_size, bool is_double_density);
+
+		bool get_is_read_only();
+		void set_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track);
+		std::shared_ptr<Track> get_track_at_position(unsigned int head, unsigned int position);
+
+	private:
+		std::mutex file_access_mutex_;
+		virtual long get_file_offset_for_position(unsigned int head, unsigned int position) = 0;
+
+		int sectors_per_track_ = 0;
+		uint8_t sector_size_ = 0;
+		bool is_double_density_ = true;
+};
+
+}
+}
+
+#endif /* SectorDump_hpp */

Storage/Disk/DiskImage/Formats/SSD.cpp

@@ -12,14 +12,12 @@
 
 namespace {
 	static const unsigned int sectors_per_track = 10;
-	static const size_t bytes_per_sector = 256;
 	static const unsigned int sector_size = 1;
 }
 
 using namespace Storage::Disk;
 
-SSD::SSD(const char *file_name) :
-		Storage::FileHolder(file_name) {
+SSD::SSD(const char *file_name) : MFMSectorDump(file_name) {
 	// very loose validation: the file needs to be a multiple of 256 bytes
 	// and not ungainly large
 
@@ -32,6 +30,8 @@ SSD::SSD(const char *file_name) :
 	track_count_ = (unsigned int)(file_stats_.st_size / (256 * 10));
 	if(track_count_ < 40) track_count_ = 40;
 	else if(track_count_ < 80) track_count_ = 80;
+
+	set_geometry(sectors_per_track, sector_size, false);
 }
 
 unsigned int SSD::get_head_position_count() {
@@ -42,37 +42,6 @@ unsigned int SSD::get_head_count() {
 	return head_count_;
 }
 
-bool SSD::get_is_read_only() {
-	return is_read_only_;
-}
-
 long SSD::get_file_offset_for_position(unsigned int head, unsigned int position) {
 	return (position * head_count_ + head) * 256 * 10;
 }
-
-std::shared_ptr<Track> SSD::get_track_at_position(unsigned int head, unsigned int position) {
-	uint8_t sectors[bytes_per_sector*sectors_per_track];
-
-	if(head >= head_count_) return nullptr;
-	long file_offset = get_file_offset_for_position(head, position);
-
-	{
-		std::lock_guard<std::mutex> lock_guard(file_access_mutex_);
-		fseek(file_, file_offset, SEEK_SET);
-		fread(sectors, 1, sizeof(sectors), file_);
-	}
-
-	return track_for_sectors(sectors, (uint8_t)position, (uint8_t)head, 0, sector_size, false);
-}
-
-void SSD::set_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track) {
-	uint8_t parsed_track[bytes_per_sector*sectors_per_track];
-	decode_sectors(*track, parsed_track, 0, sectors_per_track-1, sector_size, false);
-
-	long file_offset = get_file_offset_for_position(head, position);
-
-	std::lock_guard<std::mutex> lock_guard(file_access_mutex_);
-	ensure_file_is_at_least_length(file_offset);
-	fseek(file_, file_offset, SEEK_SET);
-	fwrite(parsed_track, 1, sizeof(parsed_track), file_);
-}

Storage/Disk/DiskImage/Formats/SSD.hpp

@@ -9,8 +9,7 @@
 #ifndef SSD_hpp
 #define SSD_hpp
 
-#include "../DiskImage.hpp"
-#include "../../../FileHolder.hpp"
+#include "MFMSectorDump.hpp"
 
 namespace Storage {
 namespace Disk {
@@ -18,7 +17,7 @@ namespace Disk {
 /*!
 	Provies a @c Disk containing a DSD or SSD disk image — a decoded sector dump of an Acorn DFS disk.
 */
-class SSD: public DiskImage, public Storage::FileHolder {
+class SSD: public MFMSectorDump {
 	public:
 		/*!
 			Construct an @c SSD containing content from the file with name @c file_name.
@@ -32,15 +31,10 @@ class SSD: public DiskImage, public Storage::FileHolder {
 			ErrorNotSSD,
 		};
 
-		// implemented to satisfy @c Disk
 		unsigned int get_head_position_count();
 		unsigned int get_head_count();
-		bool get_is_read_only();
-		void set_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track);
-		std::shared_ptr<Track> get_track_at_position(unsigned int head, unsigned int position);
 
 	private:
-		std::mutex file_access_mutex_;
 		long get_file_offset_for_position(unsigned int head, unsigned int position);
 
 		unsigned int head_count_;