Merge pull request #177 from TomHarte/DSKFileFormat

Introduces parsing of the file format support for the simplest of CPC disks

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

@@ -92,6 +92,7 @@
 		4B8378DF1F33675F005CA9E4 /* CharacterMapper.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B8378DD1F33675F005CA9E4 /* CharacterMapper.cpp */; };
 		4B8378E21F336920005CA9E4 /* CharacterMapper.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B8378E01F336920005CA9E4 /* CharacterMapper.cpp */; };
 		4B8378E51F3378C4005CA9E4 /* CharacterMapper.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B8378E31F3378C4005CA9E4 /* CharacterMapper.cpp */; };
+		4B838F1F1F35FDCD0016B5E6 /* CPCDSK.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B838F1D1F35FDCD0016B5E6 /* CPCDSK.cpp */; };
 		4B8805F01DCFC99C003085B1 /* Acorn.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B8805EE1DCFC99C003085B1 /* Acorn.cpp */; };
 		4B8805F41DCFD22A003085B1 /* Commodore.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B8805F21DCFD22A003085B1 /* Commodore.cpp */; };
 		4B8805F71DCFF6C9003085B1 /* Commodore.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 4B8805F51DCFF6C9003085B1 /* Commodore.cpp */; };
@@ -618,6 +619,8 @@
 		4B8378E11F336920005CA9E4 /* CharacterMapper.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; name = CharacterMapper.hpp; path = Oric/CharacterMapper.hpp; sourceTree = "<group>"; };
 		4B8378E31F3378C4005CA9E4 /* CharacterMapper.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = CharacterMapper.cpp; sourceTree = "<group>"; };
 		4B8378E41F3378C4005CA9E4 /* CharacterMapper.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = CharacterMapper.hpp; sourceTree = "<group>"; };
+		4B838F1D1F35FDCD0016B5E6 /* CPCDSK.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = CPCDSK.cpp; sourceTree = "<group>"; };
+		4B838F1E1F35FDCD0016B5E6 /* CPCDSK.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = CPCDSK.hpp; sourceTree = "<group>"; };
 		4B8805EE1DCFC99C003085B1 /* Acorn.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Acorn.cpp; path = Parsers/Acorn.cpp; sourceTree = "<group>"; };
 		4B8805EF1DCFC99C003085B1 /* Acorn.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; name = Acorn.hpp; path = Parsers/Acorn.hpp; sourceTree = "<group>"; };
 		4B8805F21DCFD22A003085B1 /* Commodore.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Commodore.cpp; path = Parsers/Commodore.cpp; sourceTree = "<group>"; };
@@ -1551,6 +1554,8 @@
 				4B5FADBC1DE31D1500AEC565 /* OricMFMDSK.hpp */,
 				4BF829611D8F536B001BAE39 /* SSD.cpp */,
 				4BF829621D8F536B001BAE39 /* SSD.hpp */,
+				4B838F1D1F35FDCD0016B5E6 /* CPCDSK.cpp */,
+				4B838F1E1F35FDCD0016B5E6 /* CPCDSK.hpp */,
 			);
 			path = Formats;
 			sourceTree = "<group>";
@@ -2751,6 +2756,7 @@
 				4BA22B071D8817CE0008C640 /* Disk.cpp in Sources */,
 				4BEA52661DF3472B007E74F2 /* Speaker.cpp in Sources */,
 				4BBFBB6C1EE8401E00C01E7A /* ZX8081.cpp in Sources */,
+				4B838F1F1F35FDCD0016B5E6 /* CPCDSK.cpp in Sources */,
 				4BC3B7521CD1956900F86E85 /* OutputShader.cpp in Sources */,
 				4B4C83701D4F623200CD541F /* D64.cpp in Sources */,
 				4B5073071DDD3B9400C48FBD /* ArrayBuilder.cpp in Sources */,

StaticAnalyser/StaticAnalyser.cpp

@@ -24,6 +24,7 @@
 
 // Disks
 #include "../Storage/Disk/Formats/AcornADF.hpp"
+#include "../Storage/Disk/Formats/CPCDSK.hpp"
 #include "../Storage/Disk/Formats/D64.hpp"
 #include "../Storage/Disk/Formats/G64.hpp"
 #include "../Storage/Disk/Formats/OricMFMDSK.hpp"
@@ -99,7 +100,8 @@ std::list<Target> StaticAnalyser::GetTargets(const char *file_name) {
 		Format("csw", tapes, Tape::CSW,	TargetPlatform::AllTape)						// CSW
 		Format("d64", disks, Disk::D64, TargetPlatform::Commodore)						// D64
 		Format("dsd", disks, Disk::SSD, TargetPlatform::Acorn)							// DSD
-		Format("dsk", disks, Disk::OricMFMDSK, TargetPlatform::Oric)					// DSK
+		Format("dsk", disks, Disk::CPCDSK, TargetPlatform::AmstradCPC)					// DSK (Amstrad CPC)
+		Format("dsk", disks, Disk::OricMFMDSK, TargetPlatform::Oric)					// DSK (Oric)
 		Format("g64", disks, Disk::G64, TargetPlatform::Commodore)						// G64
 		Format("o", tapes, Tape::ZX80O81P, TargetPlatform::ZX8081)						// O
 		Format("p", tapes, Tape::ZX80O81P, TargetPlatform::ZX8081)						// P

Storage/Disk/Formats/CPCDSK.cpp

@@ -0,0 +1,126 @@
+//
+//  CPCDSK.cpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 05/08/2017.
+//  Copyright © 2017 Thomas Harte. All rights reserved.
+//
+
+#include "CPCDSK.hpp"
+
+#include "../Encodings/MFM.hpp"
+
+using namespace Storage::Disk;
+
+CPCDSK::CPCDSK(const char *file_name) :
+	Storage::FileHolder(file_name), is_extended_(false) {
+	if(!check_signature("MV - CPC", 8)) {
+		is_extended_ = true;
+		if(!check_signature("EXTENDED", 8))
+			throw ErrorNotCPCDSK;
+	}
+
+	// Don't really care about about the creator; skip.
+	fseek(file_, 0x30, SEEK_SET);
+	head_position_count_ = (unsigned int)fgetc(file_);
+	head_count_ = (unsigned int)fgetc(file_);
+
+	if(is_extended_) {
+		for(unsigned int c = 0; c < head_position_count_ * head_count_; c++) {
+			track_sizes_.push_back((size_t)(fgetc(file_) << 8));
+		}
+	} else {
+		size_of_a_track_ = fgetc16le();
+	}
+}
+
+unsigned int CPCDSK::get_head_position_count() {
+	return head_position_count_;
+}
+
+unsigned int CPCDSK::get_head_count() {
+	return head_count_;
+}
+
+bool CPCDSK::get_is_read_only() {
+	// TODO: allow writing.
+	return true;
+}
+
+std::shared_ptr<Track> CPCDSK::get_uncached_track_at_position(unsigned int head, unsigned int position) {
+	// Given that thesea are interleaved images, determine which track, chronologically, is being requested.
+	unsigned int chronological_track = (position * head_count_) + head;
+
+	// All DSK images reserve 0x100 bytes for their headers.
+	long file_offset = 0x100;
+	if(is_extended_) {
+		// Tracks are a variable size in the original DSK file format; sum the lengths
+		// of all tracks prior to the interesting one to get a file offset.
+		unsigned int t = 0;
+		while(t < chronological_track && t < track_sizes_.size()) {
+			file_offset += track_sizes_[t];
+		}
+	} else {
+		// Tracks are a fixed size in the original DSK file format.
+		file_offset += size_of_a_track_ * chronological_track;
+	}
+
+	// Find the track, and skip the unused part of track information.
+	fseek(file_, file_offset + 16, SEEK_SET);
+
+	// Grab the track information.
+	fseek(file_, 5, SEEK_CUR);	// skip track number, side number, sector size — each is given per sector
+	int number_of_sectors = fgetc(file_);
+	__unused uint8_t gap3_length = (uint8_t)fgetc(file_);
+	__unused uint8_t filler_byte = (uint8_t)fgetc(file_);
+
+	// Grab the sector information
+	struct SectorInfo {
+		uint8_t track;
+		uint8_t side;
+		uint8_t sector;
+		size_t length;
+		uint8_t status1;
+		uint8_t status2;
+	};
+	std::vector<SectorInfo> sector_infos;
+	while(number_of_sectors--) {
+		SectorInfo new_sector;
+
+		new_sector.track = (uint8_t)fgetc(file_);
+		new_sector.side = (uint8_t)fgetc(file_);
+		new_sector.sector = (uint8_t)fgetc(file_);
+		new_sector.length = (size_t)(128 << fgetc(file_));
+		if(new_sector.length == 0x2000) new_sector.length = 0x1800;
+		new_sector.status1 = (uint8_t)fgetc(file_);
+		new_sector.status2 = (uint8_t)fgetc(file_);
+		fseek(file_, 2, SEEK_CUR);
+
+		sector_infos.push_back(new_sector);
+	}
+
+	// Get the sectors.
+	fseek(file_, file_offset + 0x100, SEEK_SET);
+	if(is_extended_) {
+		// TODO: everything about extended disk images
+	} else {
+		std::vector<Storage::Encodings::MFM::Sector> sectors;
+		for(auto &sector_info : sector_infos) {
+			Storage::Encodings::MFM::Sector new_sector;
+			new_sector.track = sector_info.track;
+			new_sector.side = sector_info.side;
+			new_sector.sector = sector_info.sector;
+			new_sector.data.resize(sector_info.length);
+			fread(new_sector.data.data(), sizeof(uint8_t), sector_info.length, file_);
+
+			// TODO: obey the status bytes, somehow (?)
+
+			sectors.push_back(std::move(new_sector));
+		}
+
+		// TODO: supply gay 3 length and filler byte
+		if(sectors.size()) return Storage::Encodings::MFM::GetMFMTrackWithSectors(sectors);
+	}
+
+	return nullptr;
+}

Storage/Disk/Formats/CPCDSK.hpp

@@ -0,0 +1,60 @@
+//
+//  CPCDSK.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 05/08/2017.
+//  Copyright © 2017 Thomas Harte. All rights reserved.
+//
+
+#ifndef CPCDSK_hpp
+#define CPCDSK_hpp
+
+#include "../Disk.hpp"
+#include "../../FileHolder.hpp"
+
+#include <vector>
+
+namespace Storage {
+namespace Disk {
+
+/*!
+	Provies a @c Disk containing an Amstrad CPC-stype disk image — some arrangement of sectors with status bits.
+*/
+class CPCDSK: public Disk, public Storage::FileHolder {
+	public:
+		/*!
+			Construct an @c AcornADF containing content from the file with name @c file_name.
+
+			@throws ErrorCantOpen if this file can't be opened.
+			@throws ErrorNotAcornADF if the file doesn't appear to contain an Acorn .ADF format image.
+		*/
+		CPCDSK(const char *file_name);
+
+		enum {
+			ErrorNotCPCDSK,
+		};
+
+		// implemented to satisfy @c Disk
+		unsigned int get_head_position_count();
+		unsigned int get_head_count();
+		bool get_is_read_only();
+
+	private:
+		std::shared_ptr<Track> get_uncached_track_at_position(unsigned int head, unsigned int position);
+
+		unsigned int head_count_;
+		unsigned int head_position_count_;
+		bool is_extended_;
+
+		// Used only for non-extended disks.
+		long size_of_a_track_;
+
+		// Used only for extended disks.
+		std::vector<size_t> track_sizes_;
+};
+
+}
+}
+
+
+#endif /* CPCDSK_hpp */

Storage/Disk/Formats/SSD.cpp

@@ -8,7 +8,6 @@
 
 #include "SSD.hpp"
 
-#include <sys/stat.h>
 #include "../Encodings/MFM.hpp"
 
 using namespace Storage::Disk;