diff options
Diffstat (limited to 'src/zlib.rs')
| -rw-r--r-- | src/zlib.rs | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/src/zlib.rs b/src/zlib.rs index 41816f3..f17c466 100644 --- a/src/zlib.rs +++ b/src/zlib.rs @@ -20,11 +20,11 @@ const DIST_EXTRA: [usize; 30] = [0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, const DYNAMIC_CODE_START: [usize; 3] = [3, 3, 11]; const DYNAMIC_CODE_EXTRA: [usize; 3] = [2, 3, 7]; -#[derive(Clone)] +#[derive(Clone, Debug)] struct HuffmanTree<const LENGTH: usize> { - pub len_counts: [u8; MAX_BITS + 1], - pub ordered_codes: [u16; LENGTH] + len_counts: [u8; MAX_BITS + 1], + ordered_codes: [u16; LENGTH] } impl<const LENGTH: usize> HuffmanTree<LENGTH> @@ -76,18 +76,20 @@ impl<const LENGTH: usize> HuffmanTree<LENGTH> fn decode<T: Bitstream>(&self, bitstream: &mut T) -> u16 { - let mut code: i16 = 0; + let mut code: u16 = 0; let mut first: u16 = 0; let mut index: usize = 0; - for len in 1..MAX_BITS + for len in 1..(MAX_BITS + 1) { - code |= bitstream.next_bit() as i16; - let count: i16 = self.len_counts[len] as i16; - // println!("{code} {count}"); - if code - count < first as i16 + code |= bitstream.next_bit() as u16; + let count: u16 = self.len_counts[len] as u16; + // println!("{code} {count} {len}"); + // let a = self.len_counts; + // println!("{a:?}"); + if count > code || code - count < first as u16 { - return self.ordered_codes[index + ((code - first as i16) as usize)]; + return self.ordered_codes[index + ((code - first) as usize)]; } index += count as usize; first += count as u16; @@ -218,7 +220,7 @@ pub fn zlib_decode<T: Bitstream>(mut instream: T) -> Vec<u8> final_chunk = instream.next_bit(); let compression_type = CompressionType::new(instream.next_bits(2) as u8); let t = output_buffer.len(); - println!("New chunk at pos: {t}, compression type: {compression_type:?}"); + // println!("New chunk at pos: {t}, compression type: {compression_type:?}"); if compression_type == CompressionType::Reserved { panic!("Reserved compression type should not be used"); @@ -300,10 +302,14 @@ pub fn zlib_decode<T: Bitstream>(mut instream: T) -> Vec<u8> let mut dist_tree_lens = [0u8; DIST_TREE_LEN]; dist_tree_lens[0..hdist].copy_from_slice(&code_dist_tree_lens[hlit..(hlit + hdist)]); + + // println!("{code_tree_lens:?}\n{dist_tree_lens:?}"); (HuffmanTree::new(code_tree_lens), HuffmanTree::new(dist_tree_lens)) }; + + // println!("{code_tree:?}\n{dist_tree:?}"); let mut code = 0u16; @@ -323,7 +329,8 @@ pub fn zlib_decode<T: Bitstream>(mut instream: T) -> Vec<u8> let dist = DIST_START[dist_code as usize] + instream.next_bits(DIST_EXTRA[dist_code as usize]) as usize; - let out_pos = output_buffer.len() - 1; + output_buffer.reserve(len); + let out_pos = output_buffer.len(); for i in 0..len { output_buffer.push(output_buffer[out_pos - dist + i]); |