terraform/vendor/github.com/cihub/seelog/archive/gzip/gzip.go

65 lines
1.5 KiB
Go

// Package gzip implements reading and writing of gzip format compressed files.
// See the compress/gzip package for more details.
package gzip
import (
"compress/gzip"
"fmt"
"io"
"os"
)
// Reader is an io.Reader that can be read to retrieve uncompressed data from a
// gzip-format compressed file.
type Reader struct {
gzip.Reader
name string
isEOF bool
}
// NewReader creates a new Reader reading the given reader.
func NewReader(r io.Reader, name string) (*Reader, error) {
gr, err := gzip.NewReader(r)
if err != nil {
return nil, err
}
return &Reader{
Reader: *gr,
name: name,
}, nil
}
// NextFile returns the file name. Calls subsequent to the first call will
// return EOF.
func (r *Reader) NextFile() (name string, err error) {
if r.isEOF {
return "", io.EOF
}
r.isEOF = true
return r.name, nil
}
// Writer is an io.WriteCloser. Writes to a Writer are compressed and written to w.
type Writer struct {
gzip.Writer
name string
noMoreFiles bool
}
// NextFile never returns a next file, and should not be called more than once.
func (w *Writer) NextFile(name string, _ os.FileInfo) error {
if w.noMoreFiles {
return fmt.Errorf("gzip: only accepts one file: already received %q and now %q", w.name, name)
}
w.noMoreFiles = true
w.name = name
return nil
}
// NewWriter returns a new Writer. Writes to the returned writer are compressed
// and written to w.
func NewWriter(w io.Writer) *Writer {
return &Writer{Writer: *gzip.NewWriter(w)}
}