mirror of
https://github.com/TomHarte/CLK.git
synced 2024-12-02 17:51:12 +00:00
129 lines
3.4 KiB
C++
129 lines
3.4 KiB
C++
//
|
|
// OricMFMDSK.cpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 21/11/2016.
|
|
// Copyright © 2016 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#include "OricMFMDSK.hpp"
|
|
#include "../PCMTrack.hpp"
|
|
#include "../Encodings/MFM.hpp"
|
|
|
|
using namespace Storage::Disk;
|
|
|
|
OricMFMDSK::OricMFMDSK(const char *file_name) :
|
|
Storage::FileHolder(file_name) {
|
|
if(!check_signature("MFM_DISK", 8))
|
|
throw ErrorNotOricMFMDSK;
|
|
|
|
head_count_ = fgetc32le();
|
|
track_count_ = fgetc32le();
|
|
geometry_type_ = fgetc32le();
|
|
|
|
if(geometry_type_ < 1 || geometry_type_ > 2)
|
|
throw ErrorNotOricMFMDSK;
|
|
}
|
|
|
|
OricMFMDSK::~OricMFMDSK() {
|
|
flush_updates();
|
|
}
|
|
|
|
unsigned int OricMFMDSK::get_head_position_count() {
|
|
return track_count_;
|
|
}
|
|
|
|
unsigned int OricMFMDSK::get_head_count() {
|
|
return head_count_;
|
|
}
|
|
|
|
bool OricMFMDSK::get_is_read_only() {
|
|
return is_read_only_;
|
|
}
|
|
|
|
long OricMFMDSK::get_file_offset_for_position(unsigned int head, unsigned int position) {
|
|
long seek_offset = 0;
|
|
switch(geometry_type_) {
|
|
case 1:
|
|
seek_offset = (head * track_count_) + position;
|
|
break;
|
|
case 2:
|
|
seek_offset = (position * track_count_ * head_count_) + head;
|
|
break;
|
|
}
|
|
return (seek_offset * 6400) + 256;
|
|
}
|
|
|
|
std::shared_ptr<Track> OricMFMDSK::get_uncached_track_at_position(unsigned int head, unsigned int position) {
|
|
fseek(file_, get_file_offset_for_position(head, position), SEEK_SET);
|
|
|
|
PCMSegment segment;
|
|
|
|
// The file format omits clock bits. So it's not a genuine MFM capture.
|
|
// A consumer must contextually guess when an FB, FC, etc is meant to be a control mark.
|
|
size_t track_offset = 0;
|
|
uint8_t last_header[6];
|
|
std::unique_ptr<Encodings::MFM::Encoder> encoder = Encodings::MFM::GetMFMEncoder(segment.data);
|
|
bool did_sync = false;
|
|
while(track_offset < 6250) {
|
|
uint8_t next_byte = (uint8_t)fgetc(file_);
|
|
track_offset++;
|
|
|
|
switch(next_byte) {
|
|
default: {
|
|
encoder->add_byte(next_byte);
|
|
if(did_sync) {
|
|
switch(next_byte) {
|
|
default: break;
|
|
|
|
case 0xfe:
|
|
for(int byte = 0; byte < 6; byte++) {
|
|
last_header[byte] = (uint8_t)fgetc(file_);
|
|
encoder->add_byte(last_header[byte]);
|
|
track_offset++;
|
|
if(track_offset == 6250) break;
|
|
}
|
|
break;
|
|
|
|
case 0xfb:
|
|
for(int byte = 0; byte < (128 << last_header[3]) + 2; byte++) {
|
|
encoder->add_byte((uint8_t)fgetc(file_));
|
|
track_offset++;
|
|
if(track_offset == 6250) break;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
did_sync = false;
|
|
}
|
|
break;
|
|
|
|
case 0xa1: // a synchronisation mark that implies a sector or header coming
|
|
encoder->output_short(Storage::Encodings::MFM::MFMSync);
|
|
did_sync = true;
|
|
break;
|
|
|
|
case 0xc2: // an 'ordinary' synchronisation mark
|
|
encoder->output_short(Storage::Encodings::MFM::MFMIndexSync);
|
|
break;
|
|
}
|
|
}
|
|
|
|
segment.number_of_bits = (unsigned int)(segment.data.size() * 8);
|
|
|
|
std::shared_ptr<PCMTrack> track(new PCMTrack(segment));
|
|
return track;
|
|
}
|
|
|
|
void OricMFMDSK::store_updated_track_at_position(unsigned int head, unsigned int position, const std::shared_ptr<Track> &track, std::mutex &file_access_mutex) {
|
|
Storage::Encodings::MFM::Parser parser(true, track);
|
|
std::vector<uint8_t> parsed_track = parser.get_track(0);
|
|
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);
|
|
size_t track_size = std::min((size_t)6400, parsed_track.size());
|
|
fwrite(parsed_track.data(), 1, track_size, file_);
|
|
}
|