func newGzip(b *siegreader.Buffer, path string) (decompressor, error) {
b.Quit = make(chan struct{}) // in case a stream with a closed quit channel, make a new one
_ = b.SizeNow() // in case a stream, force full read
buf, err := b.EofSlice(0, 4) // gzip stores uncompressed size in last 4 bytes of the stream
if err != nil {
return nil, err
}
sz := int64(uint32(buf[0]) | uint32(buf[1])<<8 | uint32(buf[2])<<16 | uint32(buf[3])<<24)
g, err := gzip.NewReader(siegreader.ReaderFrom(b))
return &gzipD{sz: sz, p: path, rdr: g}, err
}
