1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105

//! lzf is a very small data compression library.
//!
//! Originally written as [LibLZF](http://software.schmorp.de/pkg/liblzf.html)
//! by Marc Lehmann in portable C.
//!
//! This Rust library is a rewrite of the original C code
//! and fully compatible with compressed data from the C code (and vice versa).
//!
//! # Basic Operation
//!
//! ```rust,no_run
//! # use lzf;
//! let data = "foobar";
//!
//! let compressed = lzf::compress(data.as_bytes()).unwrap();
//!
//! let decompressed = lzf::decompress(&compressed, data.len()).unwrap();
//! ```
#![cfg_attr(feature="clippy", feature(plugin))]
#![cfg_attr(feature="clippy", plugin(clippy))]

use std::fmt;

mod compress;
mod decompress;
pub use compress::compress;
pub use decompress::decompress;

#[derive(PartialEq, Eq, Clone, Debug, Copy)]
pub enum LzfError {
    BufferTooSmall,
    DataCorrupted,
    NoCompressionPossible,
    UnknownError(i32),
}

impl fmt::Display for LzfError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match *self {
            LzfError::BufferTooSmall => {
                write!(f,
                       "the given buffer is too small to handle the uncompressed data")
            }
            LzfError::DataCorrupted => {
                write!(f, "the given data is corrupted")
            }
            LzfError::NoCompressionPossible => {
                write!(f, "the input data cannot be compressed")
            }
            LzfError::UnknownError(err) => {
                write!(f, "unknown error, code {}", err)
            }
        }
    }
}

pub type LzfResult<T> = Result<T, LzfError>;

#[test]
fn test_compress_skips_short() {
    match compress("foo".as_bytes()) {
        Ok(_) => panic!("Compression did _something_, which is wrong for 'foo'"),
        Err(err) => assert_eq!(LzfError::NoCompressionPossible, err),
    }
}

#[test]
fn test_compress_lorem() {
    let lorem = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod \
                 tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At \
                 vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, \
                 no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit \
                 amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut \
                 labore et dolore magna aliquyam erat, sed diam voluptua.";

    match compress(lorem.as_bytes()) {
        Ok(compressed) => {
            assert_eq!(272, compressed.len())
        }
        Err(err) => panic!("Compression failed with error {:?}", err),
    }
}

#[test]
fn test_compress_decompress_lorem_round() {
    let lorem = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod \
                 tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At \
                 vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, \
                 no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit \
                 amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut \
                 labore et dolore magna aliquyam erat, sed diam voluptua.";

    let compressed = match compress(lorem.as_bytes()) {
        Ok(c) => c,
        Err(err) => panic!("Compression failed with error {:?}", err),
    };

    match decompress(&compressed, lorem.len()) {
        Ok(decompressed) => {
            assert_eq!(lorem.len(), decompressed.len());
            assert_eq!(lorem.as_bytes(), &decompressed[..]);
        }
        Err(err) => panic!("Decompression failed with error {:?}", err),
    };
}