/* inflate a block of data compressed with dynamic huffman trees */
static int tinf_inflate_dynamic_block(TINF_DATA *d)
{
/* decode trees from stream */
tinf_decode_trees(d, &d->ltree, &d->dtree);
/* decode block using decoded trees */
return tinf_inflate_block_data(d, &d->ltree, &d->dtree);
}
/* inflate next byte of compressed stream */
int uzlib_uncompress(TINF_DATA *d)
{
do {
int res;
/* start a new block */
if (d->btype == -1) {
next_blk:
/* read final block flag */
d->bfinal = tinf_getbit(d);
/* read block type (2 bits) */
d->btype = tinf_read_bits(d, 2, 0);
//printf("Started new block: type=%d final=%d\n", d->btype, d->bfinal);
if (d->btype == 1) {
/* build fixed huffman trees */
tinf_build_fixed_trees(&d->ltree, &d->dtree);
} else if (d->btype == 2) {
/* decode trees from stream */
res = tinf_decode_trees(d, &d->ltree, &d->dtree);
if (res != TINF_OK) {
return res;
}
}
}
/* process current block */
switch (d->btype)
{
case 0:
/* decompress uncompressed block */
res = tinf_inflate_uncompressed_block(d);
break;
case 1:
case 2:
/* decompress block with fixed/dynamic huffman trees */
/* trees were decoded previously, so it's the same routine for both */
res = tinf_inflate_block_data(d, &d->ltree, &d->dtree);
break;
default:
return TINF_DATA_ERROR;
}
if (res == TINF_DONE && !d->bfinal) {
/* the block has ended (without producing more data), but we
can't return without data, so start procesing next block */
goto next_blk;
}
if (res != TINF_OK) {
return res;
}
} while (--d->destSize);
return TINF_OK;
}
