// secWriteLoop copies data from pr into w
// doing a nacl seal encryption on the data in the process using shared as the key
func secWriteLoop(w io.Writer, pr *io.PipeReader, shared *[32]byte) {
var failed bool
// check for an error, stops the loop and
// closes the pipe with err to signal the writer we failed
var check = func(err error) {
if err != nil {
log.Println("secWriteLoop err:", err)
if err2 := pr.CloseWithError(err); err2 != nil {
log.Println("CloseWithError failed", err2)
}
failed = true
}
}
for !failed { // until an error occurs
// read the clear message from our pipe
msg := make([]byte, 1024)
n, err := pr.Read(msg)
check(err)
// cut of the unused bytes
msg = msg[:n]
// read 24 bytes of random for our nonce
var nonce [24]byte
_, err = io.ReadFull(rand.Reader, nonce[:])
check(err)
// encrypt and sign our message with the prepended nonce
buf := box.SealAfterPrecomputation(nonce[:], msg, &nonce, shared)
// copy the sealed message with our passed writer
_, err = io.Copy(w, bytes.NewReader(buf))
check(err)
}
}
func PipeRead(pipeReader *io.PipeReader) {
var (
err error
n int
)
data := make([]byte, 1024)
for n, err = pipeReader.Read(data); err == nil; n, err = pipeReader.Read(data) {
fmt.Printf("%s\n", data[:n])
}
fmt.Println("writer 端 closewitherror后：", err)
}
func writeCmdOutput(res http.ResponseWriter, pipeReader *io.PipeReader) {
buffer := make([]byte, BUF_LEN)
for {
n, err := pipeReader.Read(buffer)
if err != nil {
pipeReader.Close()
break
}
data := buffer[0:n]
res.Write(data)
if f, ok := res.(http.Flusher); ok {
f.Flush()
}
//reset buffer
for i := 0; i < n; i++ {
buffer[i] = 0
}
}
}
func startRead(reader *io.PipeReader) {
v := make([]byte, 100)
_, _ = reader.Read(v)
fmt.Println(string(v))
}