From 85f15dee8b37ee1c813723aa47f2cf3c93766e21 Mon Sep 17 00:00:00 2001 From: Kevin Chabowski Date: Mon, 12 Aug 2013 01:04:55 +0200 Subject: Added PaddedWriter --- PaddedWriter.go | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 PaddedWriter.go diff --git a/PaddedWriter.go b/PaddedWriter.go new file mode 100644 index 0000000..f3430b5 --- /dev/null +++ b/PaddedWriter.go @@ -0,0 +1,32 @@ +package kagus + +import ( + "io" +) + +// PaddedWriter is a writer for data that needs to be padded / aligned. +type PaddedWriter struct { + cw *CountWriter + padding int +} + +func NewPaddedWriter(w io.Writer, padding int) *PaddedWriter { + return &PaddedWriter{NewCountWriter(w), padding} +} + +func (pw *PaddedWriter) Write(p []byte) (int, error) { + return pw.cw.Write(p) +} + +// Pad needs to be called if the padding should be inserted. Data is padded with zero-bytes. +func (pw *PaddedWriter) Pad() error { + mod := int(pw.cw.N % int64(pw.padding)) + if mod == 0 { + return nil + } + + paddingLen := pw.padding - mod + padding := make([]byte, paddingLen) + _, err := pw.cw.Write(padding) + return err +} -- cgit v1.2.3-54-g00ecf