libstomper/
lib.rs

1//! `libstomper` is a collection of compression algorithms
2//! For claritys sake all algorithm are represented as structs that implement the Compressor trait.
3//! A compressor is only responsible for reading and writing data and
4
5use std::error::Error;
6use std::io::prelude::*;
7pub mod huffman;
8pub mod lzw;
9
10/// Defines functions compression algorithms must implement
11pub trait Compressor {
12    fn encode<R: Read + Seek, W: Write + Seek>(input: &mut R, output: &mut W) -> Result<(), Box<dyn Error>>;
13    fn decode<R: Read + Seek, W: Write + Seek>(input: &mut R, output: &mut W) -> Result<(), Box<dyn Error>>;
14}
15
16#[cfg(test)]
17mod tests {
18    use std::fs::File;
19    use std::io::{prelude::*};
20    use tempfile::*;
21    use super::huffman::Huffman;
22    use super::Compressor;
23    use super::lzw::LZW;
24
25    #[test]
26    fn  log_huffman_performance() {
27        let mut log = File::create("../documentation/huffman_stats.txt").unwrap();
28        let mut big1 = File::open("../testfiles/big1.txt").unwrap();
29        let mut big2 = File::open("../testfiles/big2.txt").unwrap();
30        let mut big3 = File::open("../testfiles/big3.txt").unwrap();
31        let mut temp1 = tempfile().unwrap();
32        let mut temp2 = tempfile().unwrap();
33        let mut temp3 = tempfile().unwrap();
34        Huffman::encode(&mut big1, &mut temp1).unwrap();
35        Huffman::encode(&mut big2, &mut temp2).unwrap();
36        Huffman::encode(&mut big3, &mut temp3).unwrap();
37        let orig1 = big1.metadata().unwrap().len(); 
38        let orig2 = big2.metadata().unwrap().len(); 
39        let orig3 = big3.metadata().unwrap().len(); 
40        let comp1 = temp1.metadata().unwrap().len();
41        let comp2 = temp2.metadata().unwrap().len();
42        let comp3 = temp3.metadata().unwrap().len();
43        let perc1: f64 = (comp1 as f64/orig1 as f64) * 100 as f64;
44        let perc2: f64 = (comp2 as f64/orig2 as f64) * 100 as f64;
45        let perc3: f64 = (comp3 as f64/orig3 as f64) * 100 as f64;
46        let res1 = format!("\nbig1.txt: {} bytes\ncomp1: {} bytes\n{:.1}% of original\n", orig1, comp1, perc1);
47        let res2 = format!("\nbig2.txt: {} bytes\ncomp2: {} bytes\n{:.1}% of original\n", orig2, comp2, perc2);
48        let res3 = format!("\nbig3.txt: {} bytes\ncomp3: {} bytes\n{:.1}% of original\n", orig3, comp3, perc3);
49        log.write(res1.as_bytes()).unwrap();
50        log.write(res2.as_bytes()).unwrap();
51        log.write(res3.as_bytes()).unwrap();
52    }
53
54    #[test]
55    fn  log_lzw_performance() {
56        let mut log = File::create("../documentation/lzw_stats.txt").unwrap();
57        let mut big1 = File::open("../testfiles/big1.txt").unwrap();
58        let mut big2 = File::open("../testfiles/big2.txt").unwrap();
59        let mut big3 = File::open("../testfiles/big3.txt").unwrap();
60        let mut temp1 = tempfile().unwrap();
61        let mut temp2 = tempfile().unwrap();
62        let mut temp3 = tempfile().unwrap();
63        LZW::encode(&mut big1, &mut temp1).unwrap();
64        LZW::encode(&mut big2, &mut temp2).unwrap();
65        LZW::encode(&mut big3, &mut temp3).unwrap();
66        let orig1 = big1.metadata().unwrap().len(); 
67        let orig2 = big2.metadata().unwrap().len(); 
68        let orig3 = big3.metadata().unwrap().len(); 
69        let comp1 = temp1.metadata().unwrap().len();
70        let comp2 = temp2.metadata().unwrap().len();
71        let comp3 = temp3.metadata().unwrap().len();
72        let perc1: f64 = (comp1 as f64/orig1 as f64) * 100 as f64;
73        let perc2: f64 = (comp2 as f64/orig2 as f64) * 100 as f64;
74        let perc3: f64 = (comp3 as f64/orig3 as f64) * 100 as f64;
75        let res1 = format!("\norig1: {} bytes\ncomp1: {} bytes\n{:.1}% of original\n", orig1, comp1, perc1);
76        let res2 = format!("\norig2: {} bytes\ncomp2: {} bytes\n{:.1}% of original\n", orig2, comp2, perc2);
77        let res3 = format!("\norig3: {} bytes\ncomp3: {} bytes\n{:.1}% of original\n", orig3, comp3, perc3);
78        log.write(res1.as_bytes()).unwrap();
79        log.write(res2.as_bytes()).unwrap();
80        log.write(res3.as_bytes()).unwrap();
81    }
82}
libstomper/lib.rs

libstomper/
lib.rs
