zing22845/go-quicklz

go-quicklz is a complete port of QuickLZ compression algorithm in go.

go-quicklz

go-quicklz is a complete port of QuickLZ compression algorithm in go.

The official website for QuickLZ is available here.

Installation

go get github.com/Hiroko103/go-quicklz

Using

import "github.com/Hiroko103/go-quicklz"

Features

• Supports all compression levels and buffering modes
• Memory safe

Notices

Be aware that compressing files with STREAMING_BUFFER_0 mode will require an equal sized buffer.

If you plan to compress large files (>100 MB), use either STREAMING_BUFFER_100000 or STREAMING_BUFFER_1000000 mode.

Examples

File compress

qlz, err := quicklz.New(quicklz.COMPRESSION_LEVEL_1, quicklz.STREAMING_BUFFER_0)
if err != nil {
    fmt.Println(err)
    return
}
f, _ := os.Open(filePath)
source, _ := ioutil.ReadAll(f)
f.Close()
destination := make([]byte, len(source) + 400)
compressed_size, err := qlz.Compress(&source, &destination)
if err != nil {
    fmt.Println(err)
    return
}
compressed_data := destination[:compressed_size]
ioutil.WriteFile("outputFile", compressed_data, 0777)

File decompress

qlz, err := quicklz.New(quicklz.COMPRESSION_LEVEL_1, quicklz.STREAMING_BUFFER_0)
if err != nil {
    fmt.Println(err)
    return
}
f, _ := os.Open(compressedFile)
source, _ := ioutil.ReadAll(f)
f.Close()
decompressed_size := quicklz.Size_decompressed(&source)
destination := make([]byte, decompressed_size)
decompressed_size, err = qlz.Decompress(&source, &destination)
if err != nil {
    fmt.Println(err)
    return
}
ioutil.WriteFile("originalFile", destination, 0777)

Stream compress

qlz, err := quicklz.New(quicklz.COMPRESSION_LEVEL_1, quicklz.STREAMING_BUFFER_100000)
if err != nil {
    fmt.Println(err)
    return
}
f, _ := os.Open(filePath)
source := make([]byte, 10000)
destination := make([]byte, len(source) + 400)
of, _ := os.Create("compressedStream")
for {
    n, err := f.Read(source)
    if err != nil {
        if err == io.EOF {
            break
        }
    }
    part := source[:n]
    compressed_size, _ := qlz.Compress(&part, &destination)
    of.Write(destination[:compressed_size])
}
f.Close()
of.Close()

Stream decompress

qlz, err := quicklz.New(quicklz.COMPRESSION_LEVEL_1, quicklz.STREAMING_BUFFER_100000)
if err != nil {
    fmt.Println(err)
    return
}
f, _ := os.Open(compressedStream)
source := make([]byte, 10000 + 400)
destination := make([]byte, 10000)
of, _ := os.Create("originalFile")
for {
    header := source[:9]
    n, err := f.Read(header)
    if err != nil {
        if err == io.EOF {
            break
        }
    }
    if n != 9 {
        break
    }
    c := quicklz.Size_compressed(&header)
    f.Read(source[9:c])
    part := source[:c]
    d, _ := qlz.Decompress(&part, &destination)
    of.Write(destination[:d])
}
f.Close()
of.Close()

Credit

All credit goes to Lasse Mikkel Reinhold ([email protected]), the author of the original C version.

License

This software is released under the GNU General Public License v3.0.

Permissions of this strong copyleft license are conditioned on making available complete source code of licensed works and modifications, which include larger works using a licensed work, under the same license. Copyright and license notices must be preserved. Contributors provide an express grant of patent rights.

Refer to the LICENSE file for the complete text.