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authorValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
committerValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
commita990de90fe41456a23e58bd087d2f107d321f3a1 (patch)
tree15afc392522a9e85dc3332235e311b7d39352ea9 /vendor/zune-inflate/src/bitstream.rs
parent3d48cd3f81164bbfc1a755dc1d4a9a02f98c8ddd (diff)
downloadfparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.tar.xz
fparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.zip
Deleted vendor folder
Diffstat (limited to 'vendor/zune-inflate/src/bitstream.rs')
-rw-r--r--vendor/zune-inflate/src/bitstream.rs188
1 files changed, 0 insertions, 188 deletions
diff --git a/vendor/zune-inflate/src/bitstream.rs b/vendor/zune-inflate/src/bitstream.rs
deleted file mode 100644
index ff55e52..0000000
--- a/vendor/zune-inflate/src/bitstream.rs
+++ /dev/null
@@ -1,188 +0,0 @@
-//! `BitStreamReader` API
-//!
-//! This module provides an interface to read and write bits (and bytes) for
-//! huffman
-
-pub struct BitStreamReader<'src>
-{
- // buffer from which we are pulling in bits from
- // used in decompression.
- pub src: &'src [u8],
- // position in our buffer,
- pub position: usize,
- pub bits_left: u8,
- pub buffer: u64,
- pub over_read: usize
-}
-
-impl<'src> BitStreamReader<'src>
-{
- /// Create a new `BitStreamReader` instance
- ///
- /// # Expectations
- /// The buffer must be padded with fill bytes in the end,
- /// if not, this becomes UB in the refill phase.
- pub fn new(in_buffer: &'src [u8]) -> BitStreamReader<'src>
- {
- BitStreamReader {
- bits_left: 0,
- buffer: 0,
- src: in_buffer,
- position: 0,
- over_read: 0
- }
- }
- /// Refill the bitstream ensuring the buffer has bits between
- /// 56 and 63.
- ///
- #[inline(always)]
- pub fn refill(&mut self)
- {
- /*
- * The refill always guarantees refills between 56-63
- *
- * Bits stored will never go above 63 and if bits are in the range 56-63 no refills occur.
- */
- let mut buf = [0; 8];
-
- match self.src.get(self.position..self.position + 8)
- {
- Some(bytes) =>
- {
- buf.copy_from_slice(bytes);
- // create a u64 from an array of u8's
- let new_buffer = u64::from_le_bytes(buf);
- // num indicates how many bytes we actually consumed.
- let num = 63 ^ self.bits_left;
- // offset position
- self.position += (num >> 3) as usize;
- // shift number of bits
- self.buffer |= new_buffer << self.bits_left;
- // update bits left
- // bits left are now between 56-63
- self.bits_left |= 56;
- }
- None => self.refill_slow()
- }
- }
- #[inline(always)]
- pub fn refill_inner_loop(&mut self)
- {
- /*
- * The refill always guarantees refills between 56-63
- *
- * Bits stored will never go above 63 and if bits are in the range 56-63 no refills occur.
- */
- let mut buf = [0; 8];
-
- if let Some(bytes) = self.src.get(self.position..self.position + 8)
- {
- {
- buf.copy_from_slice(bytes);
- // create a u64 from an array of u8's
- let new_buffer = u64::from_le_bytes(buf);
- // num indicates how many bytes we actually consumed.
- let num = 63 ^ self.bits_left;
- // offset position
- self.position += (num >> 3) as usize;
- // shift number of bits
- self.buffer |= new_buffer << self.bits_left;
- // update bits left
- // bits left are now between 56-63
- self.bits_left |= 56;
- }
- }
- }
- #[inline(never)]
- fn refill_slow(&mut self)
- {
- let bytes = &self.src[self.position..];
-
- for byte in bytes
- {
- if self.bits_left >= 56
- {
- break;
- }
-
- self.buffer |= u64::from(*byte) << self.bits_left;
- self.bits_left += 8;
- self.position += 1;
- }
- while self.bits_left < 56
- {
- self.bits_left += 8;
- self.over_read += 1;
- }
- }
-
- #[inline(always)]
- pub fn peek_bits<const LOOKAHEAD: usize>(&self) -> usize
- {
- debug_assert!(self.bits_left >= LOOKAHEAD as u8);
- (self.buffer & ((1 << LOOKAHEAD) - 1)) as usize
- }
- #[inline(always)]
- pub fn peek_var_bits(&self, lookahead: usize) -> usize
- {
- debug_assert!(self.bits_left >= lookahead as u8);
- (self.buffer & ((1 << lookahead) - 1)) as usize
- }
-
- #[inline(always)]
- pub fn get_bits(&mut self, num_bits: u8) -> u64
- {
- debug_assert!(self.bits_left >= num_bits);
-
- let mask = (1_u64 << num_bits) - 1;
-
- let value = self.buffer & mask;
-
- self.buffer >>= num_bits;
-
- self.bits_left -= num_bits;
-
- value
- }
- /// Get number of bits left in the bit buffer.
- pub const fn get_bits_left(&self) -> u8
- {
- self.bits_left
- }
- /// Get position the stream is in this buffer
- /// Or alternatively, number of bits read.
- pub fn get_position(&self) -> usize
- {
- self.position
- .saturating_sub(usize::from(self.bits_left >> 3))
- }
-
- /// Reset buffer and bits left to zero.
- pub fn reset(&mut self)
- {
- self.buffer = 0;
- self.bits_left = 0;
- }
- /// Return true if the bit buffer can satisfy
- /// `bits` read without refilling,
- pub const fn has(&self, bits: u8) -> bool
- {
- self.bits_left >= bits
- }
-
- #[inline(always)]
- pub fn drop_bits(&mut self, bits: u8)
- {
- debug_assert!(self.bits_left >= bits);
- self.bits_left -= bits;
- self.buffer >>= bits;
- }
- /// Return the remaining bytes in this stream.
- ///
- /// This does not consider bits in the bit-buffer hence
- /// may not be accurate
- pub const fn remaining_bytes(&self) -> usize
- {
- self.src.len().saturating_sub(self.position)
- }
-}