forked from Shiloh/githaven
65 lines
1.4 KiB
Go
65 lines
1.4 KiB
Go
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package archiver
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import (
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"fmt"
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"io"
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"path/filepath"
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"github.com/dsnet/compress/bzip2"
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)
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// Bz2 facilitates bzip2 compression.
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type Bz2 struct {
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CompressionLevel int
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}
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// Compress reads in, compresses it, and writes it to out.
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func (bz *Bz2) Compress(in io.Reader, out io.Writer) error {
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w, err := bzip2.NewWriter(out, &bzip2.WriterConfig{
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Level: bz.CompressionLevel,
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})
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if err != nil {
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return err
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}
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defer w.Close()
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_, err = io.Copy(w, in)
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return err
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}
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// Decompress reads in, decompresses it, and writes it to out.
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func (bz *Bz2) Decompress(in io.Reader, out io.Writer) error {
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r, err := bzip2.NewReader(in, nil)
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if err != nil {
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return err
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}
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defer r.Close()
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_, err = io.Copy(out, r)
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return err
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}
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// CheckExt ensures the file extension matches the format.
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func (bz *Bz2) CheckExt(filename string) error {
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if filepath.Ext(filename) != ".bz2" {
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return fmt.Errorf("filename must have a .bz2 extension")
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}
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return nil
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}
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func (bz *Bz2) String() string { return "bz2" }
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// NewBz2 returns a new, default instance ready to be customized and used.
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func NewBz2() *Bz2 {
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return &Bz2{
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CompressionLevel: bzip2.DefaultCompression,
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}
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}
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// Compile-time checks to ensure type implements desired interfaces.
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var (
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_ = Compressor(new(Bz2))
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_ = Decompressor(new(Bz2))
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)
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// DefaultBz2 is a default instance that is conveniently ready to use.
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var DefaultBz2 = NewBz2()
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