dingusppc/devices/floppy/floppyimg.cpp
2022-11-17 18:03:18 +01:00

238 lines
6.8 KiB
C++

/*
DingusPPC - The Experimental PowerPC Macintosh emulator
Copyright (C) 2018-21 divingkatae and maximum
(theweirdo) spatium
(Contact divingkatae#1017 or powermax#2286 on Discord for more info)
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
/** @file Support for reading and writing of various floppy images. */
#include <devices/floppy/floppyimg.h>
#include <machines/machineproperties.h>
#include <loguru.hpp>
#include <memaccess.h>
#include <cinttypes>
#include <cstring>
#include <fstream>
#include <string>
static FlopImgType identify_image(std::ifstream& img_file)
{
// WOZ images identification strings
static uint8_t WOZ1_SIG[] = {0x57, 0x4F, 0x5A, 0x31, 0xFF, 0x0A, 0x0D, 0x0A};
static uint8_t WOZ2_SIG[] = {0x57, 0x4F, 0x5A, 0x32, 0xFF, 0x0A, 0x0D, 0x0A};
uint8_t buf[8] = { 0 };
img_file.seekg(0, std::ios::beg);
img_file.read((char *)buf, sizeof(buf));
// WOZ files are easily identified
if (!std::memcmp(buf, WOZ1_SIG, sizeof(buf))) {
return FlopImgType::WOZ1;
} else if (!std::memcmp(buf, WOZ2_SIG, sizeof(buf))) {
return FlopImgType::WOZ2;
} else {
for (int offset = 0; offset <=84; offset += 84) {
// rewind to logical block 2
img_file.seekg(2*BLOCK_SIZE + offset, std::ios::beg);
img_file.read((char *)buf, sizeof(buf));
// check for HFS/MFS signature at the start of the logical block 2
if ((buf[0] == 0x42 && buf[1] == 0x44) ||
(buf[0] == 0xD2 && buf[1] == 0xD7)) {
if (offset) {
return FlopImgType::DC42;
} else {
return FlopImgType::RAW;
}
}
}
}
return FlopImgType::UNKNOWN;
}
//======================= RAW IMAGE CONVERTER ============================
RawFloppyImg::RawFloppyImg(std::string& file_path) : FloppyImgConverter()
{
this->img_path = file_path;
}
/**
For raw images, we'll attempt to guess disk format based on image size.
*/
int RawFloppyImg::calc_phys_params()
{
std::ifstream img_file;
img_file.open(img_path, std::ios::in | std::ios::binary);
if (img_file.fail()) {
img_file.close();
LOG_F(ERROR, "RawFloppyImg: Could not open specified floppy image!");
return -1;
}
// determine image size
img_file.seekg(0, img_file.end);
this->img_size = img_file.tellg();
img_file.seekg(0, img_file.beg);
// verify image size
if (this->img_size < 5*BLOCK_SIZE) {
img_file.close();
LOG_F(ERROR, "RawFloppyImg: image too short!");
return -1;
}
if (this->img_size > MFM_HD_SIZE) {
img_file.close();
LOG_F(ERROR, "RawFloppyImg: image too big!");
return -1;
}
// raw images don't include anything other than raw disk data
this->data_size = this->img_size;
// see if user has specified disk format manually
std::string fmt = GET_STR_PROP("fdd_fmt");
if (!fmt.empty()) {
if (fmt == "GCR_400K") {
this->img_size = 409600;
} else if (fmt == "GCR_800K") {
this->img_size = 819200;
} else if (fmt == "MFM_720K") {
this->img_size = 737280;
} else if (fmt == "MFM_1440K") {
this->img_size = 1474560;
} else {
LOG_F(WARNING, "Invalid floppy disk format %s", fmt.c_str());
}
}
// guess disk format from image file size
static struct {
int capacity;
int rec_method;
int num_tracks;
int num_sectors;
int num_sides;
int density;
} size_to_params[] = {
{ 409600, 0, 80, 800, 1, 0}, // 400K GCR
{ 819200, 0, 80, 800, 2, 0}, // 800K GCR
{ 737280, 1, 80, 1440, 2, 0}, // 720K MFM
{1474560, 1, 80, 2880, 2, 1}, // 1440K MFM
};
this->rec_method = -1;
for (int i = 0; i < 4; i++) {
if (this->img_size == size_to_params[i].capacity) {
this->rec_method = size_to_params[i].rec_method;
this->num_tracks = size_to_params[i].num_tracks;
this->num_sectors = size_to_params[i].num_sectors;
this->num_sides = size_to_params[i].num_sides;
this->density = size_to_params[i].density;
// fake format byte for GCR disks
if (!this->rec_method) {
this->format_byte = (this->num_sides == 2) ? 0x22 : 0x2;
} else {
// For MFM disks this byte indicates sector size in blocks
this->format_byte = 2;
}
break;
}
}
if (this->rec_method == -1) {
LOG_F(ERROR, "RawFloppyImg: could't determine disk format from image size!");
return -1;
}
return 0;
}
/** Retrieve raw disk data. */
int RawFloppyImg::get_raw_disk_data(char* buf)
{
std::ifstream img_file;
img_file.open(img_path, std::ios::in | std::ios::binary);
if (img_file.fail()) {
img_file.close();
LOG_F(ERROR, "RawFloppyImg: Could not open specified floppy image!");
return -1;
}
img_file.seekg(0, img_file.beg);
img_file.read(buf, this->data_size);
img_file.close();
return 0;
}
/** Convert low-level disk data to high-level image data. */
int RawFloppyImg::export_data()
{
return 0;
}
FloppyImgConverter* open_floppy_image(std::string& img_path)
{
FloppyImgConverter *fconv;
std::ifstream img_file;
img_file.open(img_path, std::ios::in | std::ios::binary);
if (img_file.fail()) {
img_file.close();
LOG_F(ERROR, "Could not open specified floppy image!");
return nullptr;
}
FlopImgType itype = identify_image(img_file);
img_file.close();
switch(itype) {
case FlopImgType::RAW:
LOG_F(INFO, "Raw floppy image");
fconv = new RawFloppyImg(img_path);
break;
case FlopImgType::DC42:
LOG_F(INFO, "Disk Copy 4.2 image");
break;
case FlopImgType::WOZ1:
case FlopImgType::WOZ2:
LOG_F(INFO, "WOZ v%s image", (itype == FlopImgType::WOZ2) ? "2" : "1");
break;
default:
LOG_F(WARNING, "Unknown image format - assume RAW");
fconv = new RawFloppyImg(img_path);
}
if (fconv->calc_phys_params()) {
delete fconv;
return nullptr;
}
return fconv;
}