static int check_sequence(struct stream *s, unsigned int nr, uint8_t byte)
{
while (--nr) {
stream_next_bits(s, 16);
if ((uint8_t)mfm_decode_word(s->word) != byte)
break;
}
return !nr;
}
static void *speedball_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
while (stream_next_bit(s) != -1) {
uint32_t dat[10000], track_len, csum;
uint32_t idx_off = s->index_offset_bc - 31;
unsigned int i;
void *block;
if (s->word != 0x44894489)
continue;
if (stream_next_bits(s, 32) == -1)
goto fail;
if (mfm_decode_word(s->word) != 0xfefe)
continue;
if (stream_next_bytes(s, dat, 3*8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, &dat[0], &dat[0]);
if (be32toh(dat[0]) != ID_THBB)
continue;
mfm_decode_bytes(bc_mfm_even_odd, 4, &dat[2], &dat[2]);
track_len = be32toh(dat[2]);
if (track_len != 5952) /* track length is always 5952 */
continue;
mfm_decode_bytes(bc_mfm_even_odd, 4, &dat[4], &dat[4]);
csum = be32toh(dat[4]);
if (stream_next_bytes(s, dat, track_len*2) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, track_len, dat, dat);
for (i = 0; i < track_len / 4; i++)
csum ^= be32toh(dat[i]);
if (csum != 0)
continue;
ti->data_bitoff = idx_off;
set_all_sectors_valid(ti);
ti->bytes_per_sector = ti->len = track_len;
block = memalloc(ti->len);
memcpy(block, dat, ti->len);
return block;
}
fail:
return NULL;
}
static void *firebird_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
uint16_t *block = memalloc(ti->len);
while (stream_next_bit(s) != -1) {
uint32_t idx_off = s->index_offset_bc - 31;
uint8_t dat[2*(ti->len+2)];
if (s->word != 0x89448944)
continue;
stream_start_crc(s);
if (stream_next_bits(s, 16) == -1)
goto fail;
if (s->word != 0x89448944)
continue;
if (ti->type == TRKTYP_firebird) {
if (stream_next_bits(s, 16) == -1)
goto fail;
if (mfm_decode_word((uint16_t)s->word) != 0xff)
continue;
} else if (ti->type == TRKTYP_afterburner_data) {
if (stream_next_bytes(s, dat, 6) == -1)
goto fail;
mfm_decode_bytes(bc_mfm, 3, dat, dat);
if ((dat[0] != 0x41) || (dat[1] != 0x42) ||
(dat[2] != (tracknr/2)))
continue;
}
if (stream_next_bytes(s, dat, sizeof(dat)) == -1)
goto fail;
if (s->crc16_ccitt != 0)
continue;
mfm_decode_bytes(bc_mfm, ti->len, dat, block);
ti->data_bitoff = idx_off;
if (ti->type == TRKTYP_ikplus)
ti->data_bitoff -= 2*16; /* IK+ has a pre-sync header */
set_all_sectors_valid(ti);
return block;
}
fail:
free(block);
return NULL;
}
static void *interceptor_software_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
char *ablk;
unsigned int i;
init_track_info(ti, TRKTYP_amigados);
ablk = handlers[TRKTYP_amigados]->write_raw(d, tracknr, s);
if ((ablk == NULL) || (ti->type != TRKTYP_amigados))
goto fail;
stream_reset(s);
while (stream_next_bit(s) != -1) {
/* Sync word 0xa144 precedes the AmigaDOS block by ~2000 bits. */
if ((uint16_t)s->word != 0xa144)
continue;
ti->data_bitoff = s->index_offset_bc - 15;
/* Check for a decent-length zero sequence after the sync. */
for (i = 0; i < 32; i++)
if ((stream_next_bits(s, 32) == -1)
|| mfm_decode_word(s->word))
break;
if (i != 32)
continue;
/* Skip 104400 bits after the sync pattern. Check for 0xa145
* fill pattern, repeating. */
stream_next_bits(s, 104400-32*32);
if (s->word != 0xa145a145)
continue;
init_track_info(ti, TRKTYP_interceptor_software);
ti->total_bits = 105550;
return ablk;
}
fail:
memfree(ablk);
return NULL;
}
