conn, pool, examples/session: catch errors while waiting for response…

…, and add example for using monte.Session and monte.SessionConn

conn.go

@@ -114,7 +114,7 @@ func (c *Conn) Request(dst []byte, payload []byte) ([]byte, error) {
 
 	pr.wg.Wait()
 
-	return pr.dst, nil
+	return pr.dst, pr.err
 }
 
 func (c *Conn) init() {
@@ -369,6 +369,7 @@ func (c *Conn) close(err error) {
 
 	for seq := range c.reqs {
 		pr := c.reqs[seq]
+		pr.err = err
 		pr.wg.Done()
 
 		delete(c.reqs, seq)

examples/session/main.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"encoding/hex"
+	"fmt"
+	"github.com/lithdew/monte"
+	"net"
+)
+
+func main() {
+	check := func(err error) {
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	ln, err := net.Listen("tcp", ":4444")
+	check(err)
+	defer ln.Close()
+
+	conn, err := ln.Accept()
+	check(err)
+	defer conn.Close()
+
+	sess, err := monte.NewSession()
+	check(err)
+
+	check(sess.DoServer(conn))
+
+	fmt.Println(hex.EncodeToString(sess.SharedKey()))
+
+	sc := monte.NewSessionConn(sess.Suite(), conn)
+
+	buf := make([]byte, 1024)
+
+	for i := 0; i < 100; i++ {
+		n, err := sc.Read(buf)
+		check(err)
+
+		fmt.Println("Decrypted:", string(buf[:n]))
+	}
+
+	for i := 0; i < 100; i++ {
+		_, err = sc.Write([]byte(fmt.Sprintf("[%d] Hello from Go!", i)))
+		check(err)
+		check(sc.Flush())
+	}
+}

pool.go

@@ -32,25 +32,6 @@ func acquireContext(conn *Conn, seq uint32, buf []byte) *Context {
 
 func releaseContext(ctx *Context) { contextPool.Put(ctx) }
 
-type pendingRequest struct {
-	dst []byte         // dst to copy response to
-	wg  sync.WaitGroup // signals the caller that the response has been received
-}
-
-var pendingRequestPool sync.Pool
-
-func acquirePendingRequest(dst []byte) *pendingRequest {
-	v := pendingRequestPool.Get()
-	if v == nil {
-		v = &pendingRequest{}
-	}
-	pr := v.(*pendingRequest)
-	pr.dst = dst
-	return pr
-}
-
-func releasePendingRequest(pr *pendingRequest) { pendingRequestPool.Put(pr) }
-
 type pendingWrite struct {
 	buf  *bytebufferpool.ByteBuffer // payload
 	wait bool                       // signal to caller if they're waiting
@@ -73,6 +54,26 @@ func acquirePendingWrite(buf *bytebufferpool.ByteBuffer, wait bool) *pendingWrit
 
 func releasePendingWrite(pw *pendingWrite) { pendingWritePool.Put(pw) }
 
+type pendingRequest struct {
+	dst []byte         // dst to copy response to
+	err error          // error while waiting for response
+	wg  sync.WaitGroup // signals the caller that the response has been received
+}
+
+var pendingRequestPool sync.Pool
+
+func acquirePendingRequest(dst []byte) *pendingRequest {
+	v := pendingRequestPool.Get()
+	if v == nil {
+		v = &pendingRequest{}
+	}
+	pr := v.(*pendingRequest)
+	pr.dst = dst
+	return pr
+}
+
+func releasePendingRequest(pr *pendingRequest) { pendingRequestPool.Put(pr) }
+
 var zeroTime time.Time
 
 var timerPool sync.Pool