path: root/p2p/message_test.go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package p2p

import (
    "bytes"
    "encoding/hex"
    "fmt"
    "io"
    "runtime"
    "strings"
    "testing"
    "time"
)

func ExampleMsgPipe() {
    rw1, rw2 := MsgPipe()
    go func() {
        Send(rw1, 8, [][]byte{{0, 0}})
        Send(rw1, 5, [][]byte{{1, 1}})
        rw1.Close()
    }()

    for {
        msg, err := rw2.ReadMsg()
        if err != nil {
            break
        }
        var data [][]byte
        msg.Decode(&data)
        fmt.Printf("msg: %d, %x\n", msg.Code, data[0])
    }
    // Output:
    // msg: 8, 0000
    // msg: 5, 0101
}

func TestMsgPipeUnblockWrite(t *testing.T) {
loop:
    for i := 0; i < 100; i++ {
        rw1, rw2 := MsgPipe()
        done := make(chan struct{})
        go func() {
            if err := SendItems(rw1, 1); err == nil {
                t.Error("EncodeMsg returned nil error")
            } else if err != ErrPipeClosed {
                t.Error("EncodeMsg returned wrong error: got %v, want %v", err, ErrPipeClosed)
            }
            close(done)
        }()

        // this call should ensure that EncodeMsg is waiting to
        // deliver sometimes. if this isn't done, Close is likely to
        // be executed before EncodeMsg starts and then we won't test
        // all the cases.
        runtime.Gosched()

        rw2.Close()
        select {
        case <-done:
        case <-time.After(200 * time.Millisecond):
            t.Errorf("write didn't unblock")
            break loop
        }
    }
}

// This test should panic if concurrent close isn't implemented correctly.
func TestMsgPipeConcurrentClose(t *testing.T) {
    rw1, _ := MsgPipe()
    for i := 0; i < 10; i++ {
        go rw1.Close()
    }
}

func TestEOFSignal(t *testing.T) {
    rb := make([]byte, 10)

    // empty reader
    eof := make(chan struct{}, 1)
    sig := &eofSignal{new(bytes.Buffer), 0, eof}
    if n, err := sig.Read(rb); n != 0 || err != io.EOF {
        t.Errorf("Read returned unexpected values: (%v, %v)", n, err)
    }
    select {
    case <-eof:
    default:
        t.Error("EOF chan not signaled")
    }

    // count before error
    eof = make(chan struct{}, 1)
    sig = &eofSignal{bytes.NewBufferString("aaaaaaaa"), 4, eof}
    if n, err := sig.Read(rb); n != 4 || err != nil {
        t.Errorf("Read returned unexpected values: (%v, %v)", n, err)
    }
    select {
    case <-eof:
    default:
        t.Error("EOF chan not signaled")
    }

    // error before count
    eof = make(chan struct{}, 1)
    sig = &eofSignal{bytes.NewBufferString("aaaa"), 999, eof}
    if n, err := sig.Read(rb); n != 4 || err != nil {
        t.Errorf("Read returned unexpected values: (%v, %v)", n, err)
    }
    if n, err := sig.Read(rb); n != 0 || err != io.EOF {
        t.Errorf("Read returned unexpected values: (%v, %v)", n, err)
    }
    select {
    case <-eof:
    default:
        t.Error("EOF chan not signaled")
    }

    // no signal if neither occurs
    eof = make(chan struct{}, 1)
    sig = &eofSignal{bytes.NewBufferString("aaaaaaaaaaaaaaaaaaaaa"), 999, eof}
    if n, err := sig.Read(rb); n != 10 || err != nil {
        t.Errorf("Read returned unexpected values: (%v, %v)", n, err)
    }
    select {
    case <-eof:
        t.Error("unexpected EOF signal")
    default:
    }
}

func unhex(str string) []byte {
    b, err := hex.DecodeString(strings.Replace(str, "\n", "", -1))
    if err != nil {
        panic(fmt.Sprintf("invalid hex string: %q", str))
    }
    return b
}