static void *hellwig_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 raw[2], dat[ti->bytes_per_sector/4], csum, sum;
enum checksum_type checksum_type;
unsigned int i, two_sync;
char *block;
if ((uint16_t)s->word != 0x4489)
continue;
ti->data_bitoff = s->index_offset_bc - 15;
if (stream_next_bits(s, 16) == -1)
goto fail;
two_sync = (s->word == 0x44894489);
if (two_sync && (stream_next_bits(s, 16) == -1))
goto fail;
if (s->word != 0x44892aaa)
continue;
for (i = sum = 0; i < ARRAY_SIZE(dat); i++) {
if (stream_next_bytes(s, raw, 8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, raw, &dat[i]);
sum += be32toh(dat[i]);
}
if (stream_next_bytes(s, raw, 8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, raw, &csum);
csum = be32toh(csum);
if (csum == 0) {
checksum_type = CSUM_zeroes;
} else if (csum == 0xffffffff) {
checksum_type = CSUM_ones;
} else {
checksum_type = CSUM_data;
if (csum != sum)
continue;
}
ti->len += 1;
block = memalloc(ti->len);
memcpy(block, dat, ti->len-1);
block[ti->len-1] = checksum_type | ((two_sync?2:1) << 4);
ti->total_bits = 102000;
set_all_sectors_valid(ti);
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 *back_future3_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 raw[2], dat[ti->len/4], sum;
unsigned int i;
char *block;
if ((uint16_t)s->word != 0x4489)
continue;
ti->data_bitoff = s->index_offset - 15;
if (stream_next_bits(s, 32) == -1)
goto fail;
if (s->word != 0x552524a4)
continue;
if (stream_next_bits(s, 32) == -1)
goto fail;
if (s->word != 0x554a4945)
continue;
for (i = sum = 0; i < ti->len/4; i++) {
if (stream_next_bytes(s, raw, 8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, raw, &dat[i]);
if ( i < ti->len/4 - 1)
sum += be32toh(dat[i]);
}
/* Only verify the checksum on those tracks that are not
* listed in the track_array*/
if (find_track(tracknr) == 0)
if (sum != be32toh(dat[i-1]))
continue;
block = memalloc(ti->len);
memcpy(block, dat, ti->len);
set_all_sectors_valid(ti);
return block;
}
fail:
return NULL;
}
static void *puffys_saga_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) {
uint16_t dat[2*2818], csum;
unsigned int i;
char *block;
if (s->word != 0x44894489)
continue;
ti->data_bitoff = s->index_offset - 31;
for (i = 0; i < 30; i++) {
if (stream_next_bits(s, 32) == -1)
goto fail;
if (mfm_decode_bits(bc_mfm, s->word))
break;
}
if (i != 30)
continue;
if (stream_next_bits(s, 16) == -1)
goto fail;
if ((uint16_t)s->word != 0x4444)
continue;
if (stream_next_bytes(s, dat, sizeof(dat)) == -1)
goto fail;
mfm_decode_bytes(bc_mfm, sizeof(dat)/2, dat, dat);
csum = 0;
for (i = 1; i < 2818; i++)
csum += be16toh(dat[i]);
if ((be16toh(dat[0]) != csum) || (be16toh(dat[1]) != (tracknr/2)))
continue;
block = memalloc(ti->len);
memcpy(block, &dat[2], ti->len);
set_all_sectors_valid(ti);
return block;
}
fail:
return NULL;
}
static void *sextett_protection_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
uint32_t *block;
/* Tracks 159 & 161: no data, all same data_bitoff (==0) */
if (tracknr == 159) {
/* Track 159 is only a protection track on Disk 1. */
struct track_info *t158 = &d->di->track[158];
return (t158->type == TRKTYP_sextett_protection) ? memalloc(0) : NULL;
} else if (tracknr == 161) {
/* Track 161: Protection on all disks. */
ti->total_bits &= ~15;
return memalloc(0);
}
/* Disk 1, Track 158: find the key */
while (stream_next_bit(s) != -1) {
if (s->word != 0x92459245)
continue;
ti->data_bitoff = s->index_offset_bc - 31;
if (stream_next_bits(s, 32) == -1)
break;
block = memalloc(4);
*block = htobe32(s->word);
return block;
}
return NULL;
}
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 *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;
}
static void *psygnosis_b_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
char *block = memalloc(ti->len);
unsigned int j, k, nr_valid_blocks = 0;
while ((stream_next_bit(s) != -1) &&
(nr_valid_blocks != ti->nr_sectors)) {
uint16_t raw_dat[6*513];
uint32_t idx_off, new_valid = 0;
if ((uint16_t)s->word != 0x4489)
continue;
idx_off = s->index_offset_bc - 15;
if (stream_next_bits(s, 32) == -1)
goto done;
if (s->word != 0x552aaaaa)
continue;
for (j = 0; j < sizeof(raw_dat)/2; j++) {
uint32_t dat;
if (stream_next_bytes(s, &dat, 4) == -1)
goto done;
mfm_decode_bytes(bc_mfm_even_odd, 2, &dat, &raw_dat[j]);
}
for (j = 0; j < 6; j++) {
uint16_t *sec = &raw_dat[j*513];
uint16_t csum = be16toh(*sec++), c = 0;
for (k = 0; k < 512; k++)
c += be16toh(sec[k]);
if ((c == csum) && !is_valid_sector(ti, j)) {
memcpy(&block[j*1024], sec, 1024);
set_sector_valid(ti, j);
nr_valid_blocks++;
new_valid++;
}
}
if (new_valid)
ti->data_bitoff = idx_off;
}
done:
if (nr_valid_blocks == 0) {
free(block);
return NULL;
}
return block;
}
static void *phantom_fighter_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) {
uint16_t dat[0x1760], csum;
unsigned int i;
char *block;
if (s->word != 0x44894489)
continue;
ti->data_bitoff = s->index_offset_bc - 31;
if (stream_next_bits(s, 16) == -1)
goto fail;
for (i = 0; i < 8; i++) {
if (stream_next_bytes(s, &dat[0x2ec*i], 0x2ec*2) == -1)
goto fail;
if (stream_next_bits(s, 32) == -1)
goto fail;
}
mfm_decode_bytes(bc_mfm_even_odd, 0x1760, dat, dat);
for (i = csum = 0; i < ti->len/2; i++)
csum += be16toh(dat[i]);
if (csum != be16toh(dat[ti->len/2]))
continue;
block = memalloc(ti->len);
memcpy(block, dat, ti->len);
set_all_sectors_valid(ti);
return block;
}
fail:
return NULL;
}
static void *psygnosis_c_track0_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
uint16_t dat[V1_METABLK_WORDS+1], raw[2];
char *ablk, *block;
unsigned int i, metablk_words, ver;
init_track_info(ti, TRKTYP_amigados);
ablk = handlers[TRKTYP_amigados]->write_raw(d, tracknr, s);
if ((ablk == NULL) || (ti->type != TRKTYP_amigados))
goto fail;
for (ver = 1; ver <= 2; ver++) {
stream_reset(s);
metablk_words = (ver == 1) ? V1_METABLK_WORDS : V2_METABLK_WORDS;
while (stream_next_bit(s) != -1) {
if ((uint16_t)s->word != 0x428a)
continue;
ti->data_bitoff = s->index_offset - 15;
if ((ver == 2) &&
((stream_next_bits(s, 16) == -1) ||
((uint16_t)s->word != 0xaaaa)))
continue;
for (i = 0; i < (metablk_words + 1); i++) {
if (stream_next_bytes(s, raw, 4) == -1)
break;
mfm_decode_bytes(bc_mfm_even_odd, 2, raw, &dat[i]);
}
if (checksum(&dat[1], metablk_words, ver) != be16toh(dat[0]))
continue;
init_track_info(ti, TRKTYP_psygnosis_c_track0);
ti->len += metablk_words*2;
ti->total_bits = 105500;
block = memalloc(ti->len);
memcpy(block, ablk, 512*11);
memcpy(&block[512*11], &dat[1], metablk_words*2);
memfree(ablk);
return block;
}
}
fail:
memfree(ablk);
return NULL;
}
static void *rtype_a_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) {
uint8_t raw_dat[2*ti->len];
uint32_t csum;
char *block;
if ((uint16_t)s->word != 0x9521)
continue;
ti->data_bitoff = s->index_offset - 15;
if (stream_next_bits(s, 16) == -1)
goto fail;
if (mfm_decode_bits(bc_mfm, (uint16_t)s->word) != 0)
continue;
if (stream_next_bits(s, 32) == -1)
goto fail;
csum = mfm_decode_bits(bc_mfm_odd, s->word);
if (stream_next_bytes(s, raw_dat, 2*ti->len) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, ti->len, raw_dat, raw_dat);
if (amigados_checksum(raw_dat, ti->len) != csum)
continue;
block = memalloc(ti->len);
memcpy(block, raw_dat, ti->len);
set_all_sectors_valid(ti);
return block;
}
fail:
return NULL;
}
int stream_next_bytes(struct stream *s, void *p, unsigned int bytes)
{
unsigned int i;
unsigned char *dat = p;
for (i = 0; i < bytes; i++) {
if (stream_next_bits(s, 8) == -1)
return -1;
dat[i] = (uint8_t)s->word;
}
return 0;
}
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 *rtype_b_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) {
unsigned int i;
uint32_t raw_dat[2*ti->len/4];
uint32_t csum = 0;
char *block;
if ((uint16_t)s->word != 0x9521)
continue;
ti->data_bitoff = s->index_offset - 15;
if (stream_next_bits(s, 16) == -1)
goto fail;
if (mfm_decode_bits(bc_mfm, (uint16_t)s->word) != 0)
continue;
if (stream_next_bytes(s, raw_dat, 2*ti->len) == -1)
goto fail;
for (i = 0; i < ti->len/4; i++)
mfm_decode_bytes(bc_mfm_even_odd, 4, &raw_dat[2*i], &raw_dat[i]);
csum = amigados_checksum(raw_dat, ti->len);
csum &= 0x55555555u;
csum |= 0xaaaaaaaau;
if (stream_next_bytes(s, &raw_dat[ti->len/4], 8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4,
&raw_dat[ti->len/4], &raw_dat[ti->len/4]);
if (csum != be32toh(raw_dat[ti->len/4]))
continue;
block = memalloc(ti->len);
memcpy(block, raw_dat, ti->len);
set_all_sectors_valid(ti);
ti->total_bits = 105500;
return block;
}
fail:
return NULL;
}
static void *firebird_b_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 sync;
uint8_t raw[2], dat[ti->len], sum;
unsigned int i;
char *block;
sync = (ti->type == TRKTYP_quartz_a) ? 0x89448944 : 0x8944a92a;
if (s->word != sync)
continue;
if (ti->type == TRKTYP_quartz_b) {
if (stream_next_bits(s, 16) == -1)
goto fail;
if ((uint16_t)s->word != 0x8944)
continue;
ti->data_bitoff = s->index_offset_bc - 47;
} else
ti->data_bitoff = s->index_offset_bc - 31;
for (i = sum = 0; i < ti->len; i++) {
if (stream_next_bytes(s, raw, 2) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 1, raw, &dat[i]);
}
if (dat[2] != tracknr/2)
continue;
block = memalloc(ti->len);
memcpy(block, dat, ti->len);
set_all_sectors_valid(ti);
ti->total_bits = 100500;
return block;
}
fail:
return NULL;
}
static void *alienbreed_protection_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
uint32_t *dat = memalloc(3 * sizeof(uint32_t));
uint32_t x[2];
unsigned int i;
while (stream_next_bit(s) != -1) {
if (s->word != 0x89248924)
continue;
ti->data_bitoff = s->index_offset - 31;
/* Get the data longs. */
for (i = 0; i < 3; i++) {
stream_next_bytes(s, x, sizeof(x));
mfm_decode_bytes(bc_mfm_even_odd, 4, x, &dat[i]);
}
/* Check for a long sequence of zeroes */
for (i = 0; i < 1000; i++) {
stream_next_bits(s, 32);
if (mfm_decode_bits(bc_mfm, s->word) != 0)
break;
}
if (i == 1000)
goto found;
}
memfree(dat);
return NULL;
found:
ti->len = 3 * sizeof(uint32_t);
return dat;
}
static void *arc_development_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 raw[2], dat[12*512/4];
uint16_t csum, sum, craw[2];
unsigned int i, base;
unsigned int sec;
char *block;
/* Both formats have at least one sync word. */
if ((uint16_t)s->word != 0x4489)
continue;
ti->data_bitoff = s->index_offset_bc - 15;
if (s->word == 0x44894489) {
/* Two sync words is format B. */
ti->type = TRKTYP_arc_development_b;
ti->data_bitoff = s->index_offset_bc - 31;
} else if (ti->type == TRKTYP_arc_development_b) {
/* Format B must have two sync words. */
continue;
}
if (stream_next_bits(s, 32) == -1)
goto fail;
if (mfm_decode_bits(bc_mfm, s->word) != 0)
continue;
for (sec = base = 0; sec < ti->nr_sectors; sec++) {
for (i = sum = 0; i < 512/4; i++) {
if (stream_next_bytes(s, raw, 8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, raw, &dat[i+base]);
sum ^= (uint16_t)be32toh(dat[i+base]);
}
base += 512/4;
if (stream_next_bytes(s, craw, 4) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 2, craw, &csum);
if (sum != be16toh(csum))
goto fail;
}
/* Some releases use long tracks (for no good reason). */
stream_next_index(s);
ti->total_bits = (s->track_len_bc > 107000) ? 111000
: (s->track_len_bc > 102000) ? 105500
: 100000;
block = memalloc(ti->len);
memcpy(block, dat, ti->len);
set_all_sectors_valid(ti);
return block;
}
fail:
return NULL;
}
static void *psygnosis_a_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
char *block;
while (stream_next_bit(s) != -1) {
uint32_t raw_dat[2*ti->len/4], hdr, csum;
uint16_t sync = s->word;
bool_t two_sync;
if ((sync != 0x4489) && (sync != 0x4429))
continue;
ti->data_bitoff = s->index_offset - 15;
/* Check for second sync mark */
if (stream_next_bits(s, 16) == -1)
goto fail;
two_sync = ((uint16_t)s->word == sync);
/* Read the track number and checksum. If there's no second sync mark,
* the first 16 bits of the header info is already streamed. */
if (stream_next_bits(s, two_sync ? 32 : 16) == -1)
goto fail;
raw_dat[0] = htobe32(s->word);
if (stream_next_bytes(s, &raw_dat[1], 12) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, &raw_dat[0], &hdr);
mfm_decode_bytes(bc_mfm_even_odd, 4, &raw_dat[2], &csum);
hdr = be32toh(hdr);
csum = be32toh(csum);
if (hdr != (0xffffff00u | tracknr))
continue;
if (stream_next_bytes(s, raw_dat, sizeof(raw_dat)) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, ti->len, raw_dat, raw_dat);
if (amigados_checksum(raw_dat, ti->len) != csum)
continue;
/* Some titles (Armourgeddon, Obitus...) mastered with long tracks. */
stream_next_index(s);
if (s->track_bitlen > 103000)
ti->total_bits = 105500;
block = memalloc(ti->len + 4);
*(uint16_t *)&block[ti->len] = htobe16(sync);
*(uint16_t *)&block[ti->len+2] = two_sync ? htobe16(sync) : 0;
memcpy(block, raw_dat, ti->len);
set_all_sectors_valid(ti);
ti->len += 4; /* for the sync marks */
return block;
}
fail:
return NULL;
}
static void *federation_of_free_traders_write_raw(
struct disk *d, unsigned int tracknr, struct stream *s)
{
struct track_info *ti = &d->di->track[tracknr];
uint8_t *block = memalloc(ti->len);
unsigned int i, nr_valid_blocks = 0, least_block = ~0u;
while ((stream_next_bit(s) != -1) &&
(nr_valid_blocks != ti->nr_sectors)) {
uint32_t idx_off = s->index_offset_bc - 31;
uint16_t csum;
uint8_t sec, *p;
if (s->word != 0x44894489)
continue;
if (stream_next_bits(s, 32) == -1)
goto done;
if (mfm_decode_bits(bc_mfm, s->word) != (0xff00 | (tracknr^1)))
continue;
if (stream_next_bits(s, 16) == -1)
goto done;
sec = mfm_decode_bits(bc_mfm, (uint16_t)s->word);
if ((sec >= ti->nr_sectors) || is_valid_sector(ti, sec))
continue;
p = &block[sec * ti->bytes_per_sector];
for (i = csum = 0; i < ti->bytes_per_sector; i++) {
if (stream_next_bits(s, 16) == -1)
goto done;
csum ^= (uint16_t)s->word;
p[i] = mfm_decode_bits(bc_mfm, (uint16_t)s->word);
}
if (stream_next_bits(s, 32) == -1)
goto done;
if (csum != mfm_decode_bits(bc_mfm, s->word))
continue;
set_sector_valid(ti, sec);
nr_valid_blocks++;
if (least_block > sec) {
ti->data_bitoff = idx_off;
least_block = sec;
}
}
done:
if (nr_valid_blocks == 0) {
free(block);
return NULL;
}
for (i = 0; i < ti->nr_sectors; i++)
if (is_valid_sector(ti, i))
break;
ti->data_bitoff -= i * 0xfc8;
return block;
}
static void *zoom_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 raw[2], dat[ti->len/4], csum;
unsigned int i;
char *block;
if ((uint16_t)s->word != 0x4489)
continue;
/* Track 118 on the NTSC version only has
* 2 sync words and the PAL version has
* three.*/
if (s->word == 0xaaaa4489) {
if (stream_next_bits(s, 16) == -1)
goto fail;
if ((uint16_t)s->word != 0x4489)
continue;
ti->data_bitoff = s->index_offset_bc - 31;
if (ti->type == TRKTYP_zoom_b) {
if (stream_next_bits(s, 16) == -1)
goto fail;
if ((uint16_t)s->word != 0x4489)
continue;
ti->data_bitoff = s->index_offset_bc - 47;
}
} else {
if (stream_next_bits(s, 32) == -1)
goto fail;
if (s->word != 0x44894489)
continue;
ti->data_bitoff = s->index_offset_bc - 47;
}
for (i = 0; i < ti->len/4; i++) {
if (stream_next_bytes(s, raw, 8) == -1)
goto fail;
mfm_decode_bytes(bc_mfm_even_odd, 4, raw, &dat[i]);
}
if((uint8_t)(0xff&be32toh(dat[0])) != (uint8_t)~(tracknr^~1))
continue;
csum = 0;
for (i = csum = 0; i < ti->len/4 - 5; i++)
csum ^= be32toh(dat[i+2]);
if (csum != be32toh(dat[1]))
continue;
block = memalloc(ti->len);
memcpy(block, dat, ti->len);
set_all_sectors_valid(ti);
ti->total_bits = 102300;
return block;
}
fail:
return NULL;
}