feat: обновить методы обработки данных и улучшить обработку ошибок в библиотеке

This commit is contained in:
2026-02-11 21:43:40 +00:00
parent 3410b54793
commit 662b292b5b
7 changed files with 215 additions and 31 deletions

View File

@@ -1,19 +1,14 @@
use crate::error::Error;
use crate::Result;
use flate2::read::{DeflateDecoder, ZlibDecoder};
use flate2::read::DeflateDecoder;
use std::io::Read;
/// Decode Deflate or Zlib compressed data
/// Decode raw Deflate (RFC 1951) payload.
pub fn decode_deflate(packed: &[u8]) -> Result<Vec<u8>> {
let mut out = Vec::new();
let mut decoder = DeflateDecoder::new(packed);
if decoder.read_to_end(&mut out).is_ok() {
return Ok(out);
}
out.clear();
let mut zlib = ZlibDecoder::new(packed);
zlib.read_to_end(&mut out)
decoder
.read_to_end(&mut out)
.map_err(|_| Error::DecompressionFailed("deflate"))?;
Ok(out)
}

View File

@@ -52,14 +52,14 @@ impl<'a> LzhDecoder<'a> {
let mut out = Vec::with_capacity(expected_size);
while out.len() < expected_size {
let c = self.decode_char();
let c = self.decode_char()?;
if c < 256 {
let byte = c as u8;
out.push(byte);
self.text[self.ring_pos] = byte;
self.ring_pos = (self.ring_pos + 1) & (LZH_N - 1);
} else {
let mut offset = self.decode_position();
let mut offset = self.decode_position()?;
offset = (self.ring_pos.wrapping_sub(offset).wrapping_sub(1)) & (LZH_N - 1);
let mut length = c.saturating_sub(253);
@@ -131,29 +131,29 @@ impl<'a> LzhDecoder<'a> {
self.parent[LZH_R] = 0;
}
fn decode_char(&mut self) -> usize {
fn decode_char(&mut self) -> Result<usize> {
let mut node = self.son[LZH_R];
while node < LZH_T {
let bit = usize::from(self.bit_reader.read_bit_or_zero());
let bit = usize::from(self.bit_reader.read_bit()?);
node = self.son[node + bit];
}
let c = node - LZH_T;
self.update(c);
c
Ok(c)
}
fn decode_position(&mut self) -> usize {
let i = self.bit_reader.read_bits_or_zero(8) as usize;
fn decode_position(&mut self) -> Result<usize> {
let i = self.bit_reader.read_bits(8)? as usize;
let mut c = usize::from(self.d_code[i]) << 6;
let mut j = usize::from(self.d_len[i]).saturating_sub(2);
while j > 0 {
j -= 1;
c |= usize::from(self.bit_reader.read_bit_or_zero()) << j;
c |= usize::from(self.bit_reader.read_bit()?) << j;
}
c | (i & 0x3F)
Ok(c | (i & 0x3F))
}
fn update(&mut self, c: usize) {
@@ -264,10 +264,10 @@ impl<'a> BitReader<'a> {
}
}
fn read_bit_or_zero(&mut self) -> u8 {
fn read_bit(&mut self) -> Result<u8> {
if self.bit_mask == 0x80 {
let Some(mut byte) = self.data.get(self.byte_pos).copied() else {
return 0;
return Err(Error::DecompressionFailed("lzss-huffman: unexpected EOF"));
};
if let Some(state) = &mut self.xor_state {
byte = state.decrypt_byte(byte);
@@ -285,14 +285,14 @@ impl<'a> BitReader<'a> {
self.bit_mask = 0x80;
self.byte_pos = self.byte_pos.saturating_add(1);
}
bit
Ok(bit)
}
fn read_bits_or_zero(&mut self, bits: usize) -> u32 {
fn read_bits(&mut self, bits: usize) -> Result<u32> {
let mut value = 0u32;
for _ in 0..bits {
value = (value << 1) | u32::from(self.read_bit_or_zero());
value = (value << 1) | u32::from(self.read_bit()?);
}
value
Ok(value)
}
}