// Reset discards the state of Writer and makes it equivalent
// to the result of NewWriter or NewWriterLevel, but writing
// to dst instead.
func (w *Writer) Reset(dst io.Writer) {
w.bw = bits.NewWriter(dst)
w.block = newBlock(w.block.size)
w.crc = 0
w.wroteHeader = false
w.closed = false
w.err = nil
}
// NewWriterLevel is like NewWriter but specifies the
// compression level.
//
// The levels range from 1 (BestSpeed) to 9 (BestCompression);
// higher levels typically run slower but compress more.
//
// If level is in the range [1, 9] then the error returned will
// be nil. Otherwise the error returned will be non-nil.
func NewWriterLevel(w io.Writer, level int) (*Writer, error) {
if level < BestSpeed || level > BestCompression {
return nil, fmt.Errorf("bzip2: invalid compression level: %d", level)
}
return &Writer{
bw: bits.NewWriter(w),
block: newBlock(level * baseBlockSize),
}, nil
}
// NewWriter returns a new Writer. Writes to the returned
// writer are compressed and written to w.
//
// It is the caller's responsibility to call Close on the
// Writer when done. Writes may be buffered and not
// flushed until Close.
func NewWriter(w io.Writer) *Writer {
return &Writer{
bw: bits.NewWriter(w),
block: newBlock(6 * baseBlockSize),
}
}