Revert changes to binio.rs

This commit is contained in:
G2-Games 2024-10-18 14:21:24 -05:00
parent 4d58df5d15
commit db52e23ef7
2 changed files with 71 additions and 147 deletions

View file

@ -1,70 +1,80 @@
use std::io::{self, Read, Write}; pub struct BitIo {
data: Vec<u8>,
use byteorder::{ReadBytesExt, WriteBytesExt};
/// A simple way to write individual bits to an input implementing [Write].
pub struct BitWriter<'a, O: Write + WriteBytesExt> {
output: &'a mut O,
current_byte: u8,
byte_offset: usize, byte_offset: usize,
bit_offset: usize, bit_offset: usize,
byte_size: usize, byte_size: usize,
} }
impl<'a, O: Write + WriteBytesExt> BitWriter<'a, O> { impl BitIo {
/// Create a new BitWriter wrapper around something which /// Create a new BitIO reader and writer over some data
/// implements [Write]. pub fn new(data: Vec<u8>) -> Self {
pub fn new(output: &'a mut O) -> Self {
Self { Self {
output, data,
current_byte: 0,
byte_offset: 0, byte_offset: 0,
bit_offset: 0, bit_offset: 0,
byte_size: 0, byte_size: 0,
} }
} }
/// Get the number of whole bytes written to the stream. /// Get the byte offset of the reader
pub fn byte_offset(&self) -> usize {
self.byte_offset
}
/// Get the byte size of the reader
pub fn byte_size(&self) -> usize { pub fn byte_size(&self) -> usize {
self.byte_size self.byte_size
} }
/// Get the bit offset within the current byte. /// Get the current bytes up to `byte_size` in the reader
pub fn bit_offset(&self) -> u8 { pub fn bytes(&self) -> Vec<u8> {
self.bit_offset as u8 self.data[..self.byte_size].to_vec()
} }
/// Check if the stream is aligned to a byte. /// Read some bits from the buffer
pub fn aligned(&self) -> bool { pub fn read_bit(&mut self, bit_len: usize) -> u64 {
self.bit_offset() == 0 if bit_len > 8 * 8 {
panic!("Cannot read more than 64 bits")
} }
/// Align the writer to the nearest byte by padding with zero bits. if bit_len % 8 == 0 && self.bit_offset == 0 {
/// return self.read(bit_len / 8);
/// Returns the number of zero bits }
pub fn flush(&mut self) -> Result<usize, io::Error> {
let mut result = 0;
for i in 0..bit_len {
let bit_value = ((self.data[self.byte_offset] as usize >> self.bit_offset) & 1) as u64;
self.bit_offset += 1;
if self.bit_offset == 8 {
self.byte_offset += 1; self.byte_offset += 1;
// Write out the current byte unfinished
self.output.write_u8(self.current_byte).unwrap();
self.current_byte = 0;
self.bit_offset = 0; self.bit_offset = 0;
Ok(8 - self.bit_offset)
} }
/// Write some bits to the output. result |= bit_value << i;
}
result
}
/// Read some bytes from the buffer
pub fn read(&mut self, byte_len: usize) -> u64 {
if byte_len > 8 {
panic!("Cannot read more than 8 bytes")
}
let mut padded_slice = [0u8; 8];
padded_slice.copy_from_slice(&self.data[self.byte_offset..self.byte_offset + byte_len]);
self.byte_offset += byte_len;
u64::from_le_bytes(padded_slice)
}
/// Write some bits to the buffer
pub fn write_bit(&mut self, data: u64, bit_len: usize) { pub fn write_bit(&mut self, data: u64, bit_len: usize) {
if bit_len > 64 { if bit_len > 8 * 8 {
panic!("Cannot write more than 64 bits at once."); panic!("Cannot write more than 64 bits");
} else if bit_len == 0 {
panic!("Must write 1 or more bits.")
} }
if bit_len % 8 == 0 && self.bit_offset == 0 { if bit_len % 8 == 0 && self.bit_offset == 0 {
@ -75,115 +85,32 @@ impl<'a, O: Write + WriteBytesExt> BitWriter<'a, O> {
for i in 0..bit_len { for i in 0..bit_len {
let bit_value = (data >> i) & 1; let bit_value = (data >> i) & 1;
self.current_byte &= !(1 << self.bit_offset); self.data[self.byte_offset] &= !(1 << self.bit_offset);
self.current_byte |= (bit_value << self.bit_offset) as u8; self.data[self.byte_offset] |= (bit_value << self.bit_offset) as u8;
self.bit_offset += 1; self.bit_offset += 1;
if self.bit_offset >= 8 {
self.byte_offset += 1;
self.bit_offset = 0;
self.output.write_u8(self.current_byte).unwrap();
self.current_byte = 0;
}
}
self.byte_size = self.byte_offset + (self.bit_offset + 7) / 8;
}
/// Write some bytes to the output.
pub fn write(&mut self, data: u64, byte_len: usize) {
if byte_len > 8 {
panic!("Cannot write more than 8 bytes at once.")
} else if byte_len == 0 {
panic!("Must write 1 or more bytes.")
}
self.output
.write_all(&data.to_le_bytes()[..byte_len])
.unwrap();
self.byte_offset += byte_len;
self.byte_size = self.byte_offset + (self.bit_offset + 7) / 8;
}
}
/// A simple way to read individual bits from an input implementing [Read].
pub struct BitReader<'a, I: Read + ReadBytesExt> {
input: &'a mut I,
current_byte: Option<u8>,
byte_offset: usize,
bit_offset: usize,
}
impl<'a, I: Read + ReadBytesExt> BitReader<'a, I> {
/// Create a new BitReader wrapper around something which
/// implements [Write].
pub fn new(input: &'a mut I) -> Self {
let first = input.read_u8().unwrap();
Self {
input,
current_byte: Some(first),
byte_offset: 0,
bit_offset: 0,
}
}
/// Get the number of whole bytes read from the stream.
pub fn byte_offset(&self) -> usize {
self.byte_offset
}
/// Read some bits from the input.
pub fn read_bit(&mut self, bit_len: usize) -> u64 {
if bit_len > 64 {
panic!("Cannot read more than 64 bits at once.")
} else if bit_len == 0 {
panic!("Must read 1 or more bits.")
}
if bit_len % 8 == 0 && self.bit_offset == 0 {
return self.read(bit_len / 8);
}
let mut result = 0;
for i in 0..bit_len {
let bit_value = ((self.current_byte.unwrap() as usize >> self.bit_offset) & 1) as u64;
self.bit_offset += 1;
if self.bit_offset == 8 { if self.bit_offset == 8 {
self.byte_offset += 1; self.byte_offset += 1;
self.bit_offset = 0; self.bit_offset = 0;
}
self.current_byte = Some(self.input.read_u8().unwrap());
} }
result |= bit_value << i; self.byte_size = self.byte_offset + (self.bit_offset + 7) / 8;
} }
result pub fn write(&mut self, data: u64, byte_len: usize) {
}
/// Read some bytes from the input.
pub fn read(&mut self, byte_len: usize) -> u64 {
if byte_len > 8 { if byte_len > 8 {
panic!("Cannot read more than 8 bytes at once.") panic!("Cannot write more than 8 bytes")
} else if byte_len == 0 {
panic!("Must read 1 or more bytes")
} }
let mut padded_slice = vec![0u8; byte_len]; let mut padded_slice = [0u8; 8];
self.input.read_exact(&mut padded_slice).unwrap(); padded_slice.copy_from_slice(&data.to_le_bytes());
self.data[self.byte_offset..self.byte_offset + byte_len]
.copy_from_slice(&padded_slice[..byte_len]);
self.byte_offset += byte_len; self.byte_offset += byte_len;
let extra_length = padded_slice.len() - byte_len; self.byte_size = self.byte_offset + (self.bit_offset + 7) / 8;
padded_slice.extend_from_slice(&vec![0u8; extra_length]);
u64::from_le_bytes(padded_slice.try_into().unwrap())
} }
} }

View file

@ -4,7 +4,7 @@ use std::{
io::{Cursor, Read, Seek, Write}, io::{Cursor, Read, Seek, Write},
}; };
use crate::binio::{BitReader, BitWriter}; use crate::binio::BitIo;
use crate::common::CzError; use crate::common::CzError;
/// The size of compressed data in each chunk /// The size of compressed data in each chunk
@ -163,7 +163,7 @@ pub fn decompress2<T: Seek + ReadBytesExt + Read>(
} }
fn decompress_lzw2(input_data: &[u8], size: usize) -> Vec<u8> { fn decompress_lzw2(input_data: &[u8], size: usize) -> Vec<u8> {
let mut data = Cursor::new(input_data); let data = input_data;
let mut dictionary = HashMap::new(); let mut dictionary = HashMap::new();
for i in 0..256 { for i in 0..256 {
dictionary.insert(i as u64, vec![i as u8]); dictionary.insert(i as u64, vec![i as u8]);
@ -172,7 +172,7 @@ fn decompress_lzw2(input_data: &[u8], size: usize) -> Vec<u8> {
let mut result = Vec::with_capacity(size); let mut result = Vec::with_capacity(size);
let data_size = input_data.len(); let data_size = input_data.len();
let mut bit_io = BitReader::new(&mut data); let mut bit_io = BitIo::new(data.to_vec());
let mut w = dictionary.get(&0).unwrap().clone(); let mut w = dictionary.get(&0).unwrap().clone();
let mut element; let mut element;
@ -362,9 +362,9 @@ fn compress_lzw2(data: &[u8], last: Vec<u8>) -> (usize, Vec<u8>, Vec<u8>) {
element = last element = last
} }
let mut output_buf = Vec::new(); let output_buf = Vec::new();
let mut bit_io = BitWriter::new(&mut output_buf); let mut bit_io = BitIo::new(output_buf);
let write_bit = |bit_io: &mut BitWriter<Vec<u8>>, code: u64| { let write_bit = |bit_io: &mut BitIo, code: u64| {
if code > 0x7FFF { if code > 0x7FFF {
bit_io.write_bit(1, 1); bit_io.write_bit(1, 1);
bit_io.write_bit(code, 18); bit_io.write_bit(code, 18);
@ -403,17 +403,14 @@ fn compress_lzw2(data: &[u8], last: Vec<u8>) -> (usize, Vec<u8>, Vec<u8>) {
} }
} }
bit_io.flush().unwrap(); return (count, bit_io.bytes(), Vec::new());
return (count, output_buf, Vec::new());
} else if bit_io.byte_size() < 0x87BDF { } else if bit_io.byte_size() < 0x87BDF {
if !last_element.is_empty() { if !last_element.is_empty() {
write_bit(&mut bit_io, *dictionary.get(&last_element).unwrap()); write_bit(&mut bit_io, *dictionary.get(&last_element).unwrap());
} }
bit_io.flush().unwrap(); return (count, bit_io.bytes(), Vec::new());
return (count, output_buf, Vec::new());
} }
bit_io.flush().unwrap(); (count, bit_io.bytes(), last_element)
(count, output_buf, last_element)
} }