mame/src/lib/formats/ami_dsk.c
2011-11-11 08:40:31 +00:00

132 lines
3.1 KiB
C

/*********************************************************************
formats/ami_dsk.c
Amiga disk images
*********************************************************************/
#include "formats/ami_dsk.h"
adf_format::adf_format() : floppy_image_format_t()
{
}
const char *adf_format::name() const
{
return "adf";
}
const char *adf_format::description() const
{
return "Amiga ADF floppy disk image";
}
const char *adf_format::extensions() const
{
return "adf";
}
bool adf_format::supports_save() const
{
return true;
}
int adf_format::identify(io_generic *io)
{
UINT64 size = io_generic_size(io);
if ((size == 901120) || (size == 1802240))
{
return 50;
}
return 0;
}
bool adf_format::load(io_generic *io, floppy_image *image)
{
desc_s sectors[11];
UINT8 sectdata[512*11];
for(int i=0; i<11; i++) {
sectors[i].data = sectdata + 512*i;
sectors[i].size = 512;
sectors[i].sector_id = i;
}
for(int track=0; track < 80; track++) {
for(int side=0; side < 2; side++) {
io_generic_read(io, sectdata, (track*2 + side)*512*11, 512*11);
generate_track(amiga_11, track, side, sectors, 11, 100000, image);
}
}
return true;
}
UINT32 adf_format::g32(const UINT8 *trackbuf, int track_size, int pos)
{
if(pos >= 0 && track_size-pos >= 40) {
int pp = pos >> 3;
int dp = pos & 7;
return
(trackbuf[pp] << (24+dp)) |
(trackbuf[pp+1] << (16+dp)) |
(trackbuf[pp+2] << (8+dp)) |
(trackbuf[pp+3] << dp) |
(trackbuf[pp+4] >> (8-dp));
} else {
UINT32 res = 0;
for(int i=0; i<32; i++) {
int pp = (pos+i) % track_size;
if(trackbuf[pp>>3] & (0x80 >> (pp & 7)))
res |= 0x80000000 >> i;
}
return res;
}
}
UINT32 adf_format::checksum(const UINT8 *trackbuf, int track_size, int pos, int long_count)
{
UINT32 check = 0;
for(int i=0; i<long_count; i++)
check ^= g32(trackbuf, track_size, pos+32*i);
return check & 0x55555555;
}
bool adf_format::save(io_generic *io, floppy_image *image)
{
// TODO: HD support
UINT8 sectdata[512*11];
UINT8 trackbuf[150000/8];
for(int track=0; track < 80; track++) {
for(int side=0; side < 2; side++) {
int track_size;
generate_bitstream_from_track(track, side, 2000, trackbuf, track_size, image);
for(int i=0; i<track_size; i++)
if(g32(trackbuf, track_size, i) == 0x44894489 &&
(g32(trackbuf, track_size, i+384) & 0x55555555) == checksum(trackbuf, track_size, i+32, 10) &&
(g32(trackbuf, track_size, i+448) & 0x55555555) == checksum(trackbuf, track_size, i+480, 256)) {
UINT32 head = ((g32(trackbuf, track_size, i+32) & 0x55555555) << 1) | (g32(trackbuf, track_size, i+64) & 0x55555555);
int sect = (head >> 8) & 0xff;
if(sect > 11)
continue;
UINT8 *dest = sectdata + 512*sect;
for(int j=0; j<128; j++) {
UINT32 val = ((g32(trackbuf, track_size, i+480+32*j) & 0x55555555) << 1) | (g32(trackbuf, track_size, i+4576+32*j) & 0x55555555);
*dest++ = val >> 24;
*dest++ = val >> 16;
*dest++ = val >> 8;
*dest++ = val;
}
io_generic_write(io, sectdata, (track*2 + side)*512*11, 512*11);
}
}
}
return true;
}
const floppy_format_type FLOPPY_ADF_FORMAT = &floppy_image_format_creator<adf_format>;