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-rw-r--r--third_party/rust/miniz_oxide/src/deflate/mod.rs227
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diff --git a/third_party/rust/miniz_oxide/src/deflate/mod.rs b/third_party/rust/miniz_oxide/src/deflate/mod.rs
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+//! This module contains functionality for compression.
+
+use crate::alloc::vec;
+use crate::alloc::vec::Vec;
+
+mod buffer;
+pub mod core;
+pub mod stream;
+use self::core::*;
+
+/// How much processing the compressor should do to compress the data.
+/// `NoCompression` and `Bestspeed` have special meanings, the other levels determine the number
+/// of checks for matches in the hash chains and whether to use lazy or greedy parsing.
+#[repr(i32)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+pub enum CompressionLevel {
+ /// Don't do any compression, only output uncompressed blocks.
+ NoCompression = 0,
+ /// Fast compression. Uses a special compression routine that is optimized for speed.
+ BestSpeed = 1,
+ /// Slow/high compression. Do a lot of checks to try to find good matches.
+ BestCompression = 9,
+ /// Even more checks, can be very slow.
+ UberCompression = 10,
+ /// Default compromise between speed and compression.
+ DefaultLevel = 6,
+ /// Use the default compression level.
+ DefaultCompression = -1,
+}
+
+// Missing safe rust analogue (this and mem-to-mem are quite similar)
+/*
+fn tdefl_compress(
+ d: Option<&mut CompressorOxide>,
+ in_buf: *const c_void,
+ in_size: Option<&mut usize>,
+ out_buf: *mut c_void,
+ out_size: Option<&mut usize>,
+ flush: TDEFLFlush,
+) -> TDEFLStatus {
+ let res = match d {
+ None => {
+ in_size.map(|size| *size = 0);
+ out_size.map(|size| *size = 0);
+ (TDEFLStatus::BadParam, 0, 0)
+ },
+ Some(compressor) => {
+ let callback_res = CallbackOxide::new(
+ compressor.callback_func.clone(),
+ in_buf,
+ in_size,
+ out_buf,
+ out_size,
+ );
+
+ if let Ok(mut callback) = callback_res {
+ let res = compress(compressor, &mut callback, flush);
+ callback.update_size(Some(res.1), Some(res.2));
+ res
+ } else {
+ (TDEFLStatus::BadParam, 0, 0)
+ }
+ }
+ };
+ res.0
+}*/
+
+// Missing safe rust analogue
+/*
+fn tdefl_init(
+ d: Option<&mut CompressorOxide>,
+ put_buf_func: PutBufFuncPtr,
+ put_buf_user: *mut c_void,
+ flags: c_int,
+) -> TDEFLStatus {
+ if let Some(d) = d {
+ *d = CompressorOxide::new(
+ put_buf_func.map(|func|
+ CallbackFunc { put_buf_func: func, put_buf_user: put_buf_user }
+ ),
+ flags as u32,
+ );
+ TDEFLStatus::Okay
+ } else {
+ TDEFLStatus::BadParam
+ }
+}*/
+
+// Missing safe rust analogue (though maybe best served by flate2 front-end instead)
+/*
+fn tdefl_compress_mem_to_output(
+ buf: *const c_void,
+ buf_len: usize,
+ put_buf_func: PutBufFuncPtr,
+ put_buf_user: *mut c_void,
+ flags: c_int,
+) -> bool*/
+
+// Missing safe Rust analogue
+/*
+fn tdefl_compress_mem_to_mem(
+ out_buf: *mut c_void,
+ out_buf_len: usize,
+ src_buf: *const c_void,
+ src_buf_len: usize,
+ flags: c_int,
+) -> usize*/
+
+/// Compress the input data to a vector, using the specified compression level (0-10).
+pub fn compress_to_vec(input: &[u8], level: u8) -> Vec<u8> {
+ compress_to_vec_inner(input, level, 0, 0)
+}
+
+/// Compress the input data to a vector, using the specified compression level (0-10), and with a
+/// zlib wrapper.
+pub fn compress_to_vec_zlib(input: &[u8], level: u8) -> Vec<u8> {
+ compress_to_vec_inner(input, level, 1, 0)
+}
+
+/// Simple function to compress data to a vec.
+fn compress_to_vec_inner(input: &[u8], level: u8, window_bits: i32, strategy: i32) -> Vec<u8> {
+ // The comp flags function sets the zlib flag if the window_bits parameter is > 0.
+ let flags = create_comp_flags_from_zip_params(level.into(), window_bits, strategy);
+ let mut compressor = CompressorOxide::new(flags);
+ let mut output = vec![0; ::core::cmp::max(input.len() / 2, 2)];
+
+ let mut in_pos = 0;
+ let mut out_pos = 0;
+ loop {
+ let (status, bytes_in, bytes_out) = compress(
+ &mut compressor,
+ &input[in_pos..],
+ &mut output[out_pos..],
+ TDEFLFlush::Finish,
+ );
+
+ out_pos += bytes_out;
+ in_pos += bytes_in;
+
+ match status {
+ TDEFLStatus::Done => {
+ output.truncate(out_pos);
+ break;
+ }
+ TDEFLStatus::Okay => {
+ // We need more space, so resize the vector.
+ if output.len().saturating_sub(out_pos) < 30 {
+ output.resize(output.len() * 2, 0)
+ }
+ }
+ // Not supposed to happen unless there is a bug.
+ _ => panic!("Bug! Unexpectedly failed to compress!"),
+ }
+ }
+
+ output
+}
+
+#[cfg(test)]
+mod test {
+ use super::{compress_to_vec, compress_to_vec_inner, CompressionStrategy};
+ use crate::inflate::decompress_to_vec;
+ use alloc::vec;
+
+ /// Test deflate example.
+ ///
+ /// Check if the encoder produces the same code as the example given by Mark Adler here:
+ /// https://stackoverflow.com/questions/17398931/deflate-encoding-with-static-huffman-codes/17415203
+ #[test]
+ fn compress_small() {
+ let test_data = b"Deflate late";
+ let check = [
+ 0x73, 0x49, 0x4d, 0xcb, 0x49, 0x2c, 0x49, 0x55, 0x00, 0x11, 0x00,
+ ];
+
+ let res = compress_to_vec(test_data, 1);
+ assert_eq!(&check[..], res.as_slice());
+
+ let res = compress_to_vec(test_data, 9);
+ assert_eq!(&check[..], res.as_slice());
+ }
+
+ #[test]
+ fn compress_huff_only() {
+ let test_data = b"Deflate late";
+
+ let res = compress_to_vec_inner(test_data, 1, 0, CompressionStrategy::HuffmanOnly as i32);
+ let d = decompress_to_vec(res.as_slice()).expect("Failed to decompress!");
+ assert_eq!(test_data, d.as_slice());
+ }
+
+ /// Test that a raw block compresses fine.
+ #[test]
+ fn compress_raw() {
+ let text = b"Hello, zlib!";
+ let encoded = {
+ let len = text.len();
+ let notlen = !len;
+ let mut encoded = vec![
+ 1,
+ len as u8,
+ (len >> 8) as u8,
+ notlen as u8,
+ (notlen >> 8) as u8,
+ ];
+ encoded.extend_from_slice(&text[..]);
+ encoded
+ };
+
+ let res = compress_to_vec(text, 0);
+ assert_eq!(encoded, res.as_slice());
+ }
+
+ #[test]
+ fn short() {
+ let test_data = [10, 10, 10, 10, 10, 55];
+ let c = compress_to_vec(&test_data, 9);
+
+ let d = decompress_to_vec(c.as_slice()).expect("Failed to decompress!");
+ assert_eq!(&test_data, d.as_slice());
+ // Check that a static block is used here, rather than a raw block
+ // , so the data is actually compressed.
+ // (The optimal compressed length would be 5, but neither miniz nor zlib manages that either
+ // as neither checks matches against the byte at index 0.)
+ assert!(c.len() <= 6);
+ }
+}