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#![crate_name = "flate"]
#![unstable(feature = "rustc_private", issue = "27812")]
#![crate_type = "rlib"]
#![crate_type = "dylib"]
#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
html_root_url = "https://doc.rust-lang.org/nightly/",
test(attr(deny(warnings))))]
#![deny(warnings)]
#![feature(libc)]
#![feature(staged_api)]
#![feature(unique)]
#![cfg_attr(test, feature(rand))]
extern crate libc;
use libc::{c_int, c_void, size_t};
use std::fmt;
use std::ops::Deref;
use std::ptr::Unique;
use std::slice;
#[derive(Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
pub struct Error {
_unused: (),
}
impl Error {
fn new() -> Error {
Error { _unused: () }
}
}
impl fmt::Debug for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
"decompression error".fmt(f)
}
}
pub struct Bytes {
ptr: Unique<u8>,
len: usize,
}
impl Deref for Bytes {
type Target = [u8];
fn deref(&self) -> &[u8] {
unsafe { slice::from_raw_parts(*self.ptr, self.len) }
}
}
impl Drop for Bytes {
fn drop(&mut self) {
unsafe {
libc::free(*self.ptr as *mut _);
}
}
}
extern "C" {
fn tdefl_compress_mem_to_heap(psrc_buf: *const c_void,
src_buf_len: size_t,
pout_len: *mut size_t,
flags: c_int)
-> *mut c_void;
fn tinfl_decompress_mem_to_heap(psrc_buf: *const c_void,
src_buf_len: size_t,
pout_len: *mut size_t,
flags: c_int)
-> *mut c_void;
}
const LZ_FAST: c_int = 0x01;
const TDEFL_GREEDY_PARSING_FLAG: c_int = 0x04000;
pub fn deflate_bytes(bytes: &[u8]) -> Bytes {
let flags = LZ_FAST | TDEFL_GREEDY_PARSING_FLAG;
unsafe {
let mut outsz: size_t = 0;
let res = tdefl_compress_mem_to_heap(bytes.as_ptr() as *const _,
bytes.len() as size_t,
&mut outsz,
flags);
assert!(!res.is_null());
Bytes {
ptr: Unique::new(res as *mut u8),
len: outsz as usize,
}
}
}
pub fn inflate_bytes(bytes: &[u8]) -> Result<Bytes, Error> {
let flags = 0;
unsafe {
let mut outsz: size_t = 0;
let res = tinfl_decompress_mem_to_heap(bytes.as_ptr() as *const _,
bytes.len() as size_t,
&mut outsz,
flags);
if !res.is_null() {
Ok(Bytes {
ptr: Unique::new(res as *mut u8),
len: outsz as usize,
})
} else {
Err(Error::new())
}
}
}
#[cfg(test)]
mod tests {
#![allow(deprecated)]
use super::{deflate_bytes, inflate_bytes};
use std::__rand::{Rng, thread_rng};
#[test]
fn test_flate_round_trip() {
let mut r = thread_rng();
let mut words = vec![];
for _ in 0..20 {
let range = r.gen_range(1, 10);
let v = r.gen_iter::<u8>().take(range).collect::<Vec<u8>>();
words.push(v);
}
for _ in 0..20 {
let mut input = vec![];
for _ in 0..2000 {
input.extend_from_slice(r.choose(&words).unwrap());
}
let cmp = deflate_bytes(&input);
let out = inflate_bytes(&cmp).unwrap();
assert_eq!(&*input, &*out);
}
}
#[test]
fn test_zlib_flate() {
let bytes = vec![1, 2, 3, 4, 5];
let deflated = deflate_bytes(&bytes);
let inflated = inflate_bytes(&deflated).unwrap();
assert_eq!(&*inflated, &*bytes);
}
}