/** WARNING: this is duplicated in itread.c */
static int it_seek(DUMBFILE *f, long offset)
{
long pos = dumbfile_pos(f);
if (pos > offset)
return -1;
if (pos < offset)
if (dumbfile_skip(f, offset - pos))
return -1;
return 0;
}
/** WARNING: this is duplicated in itread.c */
static int it_seek(DUMBFILE *f, int32 offset)
{
int32 pos = dumbfile_pos(f);
if (pos > offset) {
return -1;
}
if (pos < offset)
if (dumbfile_skip(f, offset - pos))
return -1;
return 0;
}
static int it_riff_dsmf_process_pattern( IT_PATTERN * pattern, DUMBFILE * f, int len )
{
int length, row;
unsigned flags;
long start, end;
int p, q, r;
IT_ENTRY * entry;
length = dumbfile_igetw( f );
if ( length > len ) return -1;
len = length - 2;
pattern->n_rows = 64;
pattern->n_entries = 64;
row = 0;
start = dumbfile_pos( f );
end = start + len;
while ( (row < 64) && !dumbfile_error( f ) && (dumbfile_pos( f ) < end) ) {
p = dumbfile_getc( f );
if ( ! p ) {
++ row;
continue;
}
flags = p & 0xF0;
if (flags) {
++ pattern->n_entries;
if (flags & 0x80) dumbfile_skip( f, 1 );
if (flags & 0x40) dumbfile_skip( f, 1 );
if (flags & 0x20) dumbfile_skip( f, 1 );
if (flags & 0x10) dumbfile_skip( f, 2 );
}
}
if ( pattern->n_entries == 64 ) return 0;
pattern->entry = malloc( pattern->n_entries * sizeof( * pattern->entry ) );
if ( ! pattern->entry ) return -1;
entry = pattern->entry;
row = 0;
if ( dumbfile_seek( f, start, DFS_SEEK_SET ) ) return -1;
while ( ( row < 64 ) && !dumbfile_error( f ) && ( dumbfile_pos( f ) < end ) )
{
p = dumbfile_getc( f );
if ( ! p )
{
IT_SET_END_ROW( entry );
++ entry;
++ row;
continue;
}
flags = p;
entry->channel = flags & 0x0F;
entry->mask = 0;
if ( flags & 0xF0 )
{
if ( flags & 0x80 )
{
q = dumbfile_getc( f );
if ( q )
{
entry->mask |= IT_ENTRY_NOTE;
entry->note = q - 1;
}
}
if ( flags & 0x40 )
{
q = dumbfile_getc( f );
if ( q )
{
entry->mask |= IT_ENTRY_INSTRUMENT;
entry->instrument = q;
}
}
if ( flags & 0x20 )
{
entry->mask |= IT_ENTRY_VOLPAN;
entry->volpan = dumbfile_getc( f );
}
if ( flags & 0x10 )
{
q = dumbfile_getc( f );
r = dumbfile_getc( f );
_dumb_it_xm_convert_effect( q, r, entry, 0 );
}
if (entry->mask) entry++;
}
}
while ( row < 64 )
{
IT_SET_END_ROW( entry );
++ entry;
++ row;
}
pattern->n_entries = entry - pattern->entry;
if ( ! pattern->n_entries ) return -1;
return 0;
}
struct riff *riff_parse(DUMBFILE *f, long offset, long size, unsigned proper) {
unsigned stream_size;
struct riff *stream;
if (size < 8)
return 0;
if (dumbfile_seek(f, offset, DFS_SEEK_SET))
return 0;
if (dumbfile_mgetl(f) != DUMB_ID('R', 'I', 'F', 'F'))
return 0;
stream_size = (int)dumbfile_igetl(f);
if (stream_size + 8 > size)
return 0;
if (stream_size < 4)
return 0;
stream = (struct riff *)malloc(sizeof(struct riff));
if (!stream)
return 0;
stream->type = (int)dumbfile_mgetl(f);
stream->chunk_count = 0;
stream->chunks = 0;
stream_size -= 4;
while (stream_size && !dumbfile_error(f)) {
struct riff_chunk *chunk;
if (stream_size < 8)
break;
stream->chunks = (struct riff_chunk *)realloc(
stream->chunks,
(stream->chunk_count + 1) * sizeof(struct riff_chunk));
if (!stream->chunks)
break;
chunk = stream->chunks + stream->chunk_count;
chunk->type = (int)dumbfile_mgetl(f);
chunk->size = (int)dumbfile_igetl(f);
chunk->offset = dumbfile_pos(f);
stream_size -= 8;
if (stream_size < chunk->size)
break;
if (chunk->type == DUMB_ID('R', 'I', 'F', 'F')) {
chunk->nested =
riff_parse(f, chunk->offset - 8, chunk->size + 8, proper);
if (!chunk->nested)
break;
} else {
chunk->nested = 0;
}
dumbfile_seek(f, chunk->offset + chunk->size, DFS_SEEK_SET);
stream_size -= chunk->size;
if (proper && (chunk->size & 1)) {
dumbfile_skip(f, 1);
--stream_size;
}
++stream->chunk_count;
}
if (stream_size) {
riff_free(stream);
stream = 0;
}
return stream;
}