go-ethereum/vendor/github.com/jackpal/go-nat-pmp/network.go
Péter Szilágyi 289b30715d Godeps, vendor: convert dependency management to trash (#3198)
This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.
2016-10-28 19:05:01 +02:00

90 lines
1.8 KiB
Go

package natpmp
import (
"fmt"
"net"
"time"
)
const nAT_PMP_PORT = 5351
const nAT_TRIES = 9
const nAT_INITIAL_MS = 250
// A caller that implements the NAT-PMP RPC protocol.
type network struct {
gateway net.IP
}
func (n *network) call(msg []byte, timeout time.Duration) (result []byte, err error) {
var server net.UDPAddr
server.IP = n.gateway
server.Port = nAT_PMP_PORT
conn, err := net.DialUDP("udp", nil, &server)
if err != nil {
return
}
defer conn.Close()
// 16 bytes is the maximum result size.
result = make([]byte, 16)
var finalTimeout time.Time
if timeout != 0 {
finalTimeout = time.Now().Add(timeout)
}
needNewDeadline := true
var tries uint
for tries = 0; (tries < nAT_TRIES && finalTimeout.IsZero()) || time.Now().Before(finalTimeout); {
if needNewDeadline {
nextDeadline := time.Now().Add((nAT_INITIAL_MS << tries) * time.Millisecond)
err = conn.SetDeadline(minTime(nextDeadline, finalTimeout))
if err != nil {
return
}
needNewDeadline = false
}
_, err = conn.Write(msg)
if err != nil {
return
}
var bytesRead int
var remoteAddr *net.UDPAddr
bytesRead, remoteAddr, err = conn.ReadFromUDP(result)
if err != nil {
if err.(net.Error).Timeout() {
tries++
needNewDeadline = true
continue
}
return
}
if !remoteAddr.IP.Equal(n.gateway) {
// Ignore this packet.
// Continue without increasing retransmission timeout or deadline.
continue
}
// Trim result to actual number of bytes received
if bytesRead < len(result) {
result = result[:bytesRead]
}
return
}
err = fmt.Errorf("Timed out trying to contact gateway")
return
}
func minTime(a, b time.Time) time.Time {
if a.IsZero() {
return b
}
if b.IsZero() {
return a
}
if a.Before(b) {
return a
}
return b
}