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CLK/StaticAnalyser/Acorn/Disk.cpp

106 lines
4.7 KiB
C++

//
// Disk.cpp
// Clock Signal
//
// Created by Thomas Harte on 18/09/2016.
// Copyright © 2016 Thomas Harte. All rights reserved.
//
#include "Disk.hpp"
#include "../../Storage/Disk/Controller/DiskController.hpp"
#include "../../Storage/Disk/Encodings/MFM/Parser.hpp"
#include "../../NumberTheory/CRC.hpp"
#include <algorithm>
using namespace StaticAnalyser::Acorn;
std::unique_ptr<Catalogue> StaticAnalyser::Acorn::GetDFSCatalogue(const std::shared_ptr<Storage::Disk::Disk> &disk) {
// c.f. http://beebwiki.mdfs.net/Acorn_DFS_disc_format
std::unique_ptr<Catalogue> catalogue(new Catalogue);
Storage::Encodings::MFM::Parser parser(false, disk);
Storage::Encodings::MFM::Sector *names = parser.get_sector(0, 0, 0);
Storage::Encodings::MFM::Sector *details = parser.get_sector(0, 0, 1);
if(!names || !details) return nullptr;
if(names->samples.empty() || details->samples.empty()) return nullptr;
if(names->samples[0].size() != 256 || details->samples[0].size() != 256) return nullptr;
uint8_t final_file_offset = details->samples[0][5];
if(final_file_offset&7) return nullptr;
if(final_file_offset < 8) return nullptr;
char disk_name[13];
snprintf(disk_name, 13, "%.8s%.4s", &names->samples[0][0], &details->samples[0][0]);
catalogue->name = disk_name;
switch((details->samples[0][6] >> 4)&3) {
case 0: catalogue->bootOption = Catalogue::BootOption::None; break;
case 1: catalogue->bootOption = Catalogue::BootOption::LoadBOOT; break;
case 2: catalogue->bootOption = Catalogue::BootOption::RunBOOT; break;
case 3: catalogue->bootOption = Catalogue::BootOption::ExecBOOT; break;
}
// DFS files are stored contiguously, and listed in descending order of distance from track 0.
// So iterating backwards implies the least amount of seeking.
for(std::size_t file_offset = final_file_offset - 8; file_offset > 0; file_offset -= 8) {
File new_file;
char name[10];
snprintf(name, 10, "%c.%.7s", names->samples[0][file_offset + 7] & 0x7f, &names->samples[0][file_offset]);
new_file.name = name;
new_file.load_address = (uint32_t)(details->samples[0][file_offset] | (details->samples[0][file_offset+1] << 8) | ((details->samples[0][file_offset+6]&0x0c) << 14));
new_file.execution_address = (uint32_t)(details->samples[0][file_offset+2] | (details->samples[0][file_offset+3] << 8) | ((details->samples[0][file_offset+6]&0xc0) << 10));
new_file.is_protected = !!(names->samples[0][file_offset + 7] & 0x80);
long data_length = static_cast<long>(details->samples[0][file_offset+4] | (details->samples[0][file_offset+5] << 8) | ((details->samples[0][file_offset+6]&0x30) << 12));
int start_sector = details->samples[0][file_offset+7] | ((details->samples[0][file_offset+6]&0x03) << 8);
new_file.data.reserve(static_cast<std::size_t>(data_length));
if(start_sector < 2) continue;
while(data_length > 0) {
uint8_t sector = static_cast<uint8_t>(start_sector % 10);
uint8_t track = static_cast<uint8_t>(start_sector / 10);
start_sector++;
Storage::Encodings::MFM::Sector *next_sector = parser.get_sector(0, track, sector);
if(!next_sector) break;
long length_from_sector = std::min(data_length, 256l);
new_file.data.insert(new_file.data.end(), next_sector->samples[0].begin(), next_sector->samples[0].begin() + length_from_sector);
data_length -= length_from_sector;
}
if(!data_length) catalogue->files.push_front(new_file);
}
return catalogue;
}
std::unique_ptr<Catalogue> StaticAnalyser::Acorn::GetADFSCatalogue(const std::shared_ptr<Storage::Disk::Disk> &disk) {
std::unique_ptr<Catalogue> catalogue(new Catalogue);
Storage::Encodings::MFM::Parser parser(true, disk);
Storage::Encodings::MFM::Sector *free_space_map_second_half = parser.get_sector(0, 0, 1);
if(!free_space_map_second_half) return nullptr;
std::vector<uint8_t> root_directory;
root_directory.reserve(5 * 256);
for(uint8_t c = 2; c < 7; c++) {
Storage::Encodings::MFM::Sector *sector = parser.get_sector(0, 0, c);
if(!sector) return nullptr;
root_directory.insert(root_directory.end(), sector->samples[0].begin(), sector->samples[0].end());
}
// Quick sanity checks.
if(root_directory[0x4cb]) return nullptr;
if(root_directory[1] != 'H' || root_directory[2] != 'u' || root_directory[3] != 'g' || root_directory[4] != 'o') return nullptr;
if(root_directory[0x4FB] != 'H' || root_directory[0x4FC] != 'u' || root_directory[0x4FD] != 'g' || root_directory[0x4FE] != 'o') return nullptr;
switch(free_space_map_second_half->samples[0][0xfd]) {
default: catalogue->bootOption = Catalogue::BootOption::None; break;
case 1: catalogue->bootOption = Catalogue::BootOption::LoadBOOT; break;
case 2: catalogue->bootOption = Catalogue::BootOption::RunBOOT; break;
case 3: catalogue->bootOption = Catalogue::BootOption::ExecBOOT; break;
}
return catalogue;
}