update group ci

server/ports/ports.go

@@ -0,0 +1,180 @@
+package ports
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+)
+
+const (
+	MinPort                    = 1
+	MaxPort                    = 65535
+	MaxPortReservedDuration    = time.Duration(24) * time.Hour
+	CleanReservedPortsInterval = time.Hour
+)
+
+var (
+	ErrPortAlreadyUsed = errors.New("port already used")
+	ErrPortNotAllowed  = errors.New("port not allowed")
+	ErrPortUnAvailable = errors.New("port unavailable")
+	ErrNoAvailablePort = errors.New("no available port")
+)
+
+type PortCtx struct {
+	ProxyName  string
+	Port       int
+	Closed     bool
+	UpdateTime time.Time
+}
+
+type PortManager struct {
+	reservedPorts map[string]*PortCtx
+	usedPorts     map[int]*PortCtx
+	freePorts     map[int]struct{}
+
+	bindAddr string
+	netType  string
+	mu       sync.Mutex
+}
+
+func NewPortManager(netType string, bindAddr string, allowPorts map[int]struct{}) *PortManager {
+	pm := &PortManager{
+		reservedPorts: make(map[string]*PortCtx),
+		usedPorts:     make(map[int]*PortCtx),
+		freePorts:     make(map[int]struct{}),
+		bindAddr:      bindAddr,
+		netType:       netType,
+	}
+	if len(allowPorts) > 0 {
+		for port, _ := range allowPorts {
+			pm.freePorts[port] = struct{}{}
+		}
+	} else {
+		for i := MinPort; i <= MaxPort; i++ {
+			pm.freePorts[i] = struct{}{}
+		}
+	}
+	go pm.cleanReservedPortsWorker()
+	return pm
+}
+
+func (pm *PortManager) Acquire(name string, port int) (realPort int, err error) {
+	portCtx := &PortCtx{
+		ProxyName:  name,
+		Closed:     false,
+		UpdateTime: time.Now(),
+	}
+
+	var ok bool
+
+	pm.mu.Lock()
+	defer func() {
+		if err == nil {
+			portCtx.Port = realPort
+		}
+		pm.mu.Unlock()
+	}()
+
+	// check reserved ports first
+	if port == 0 {
+		if ctx, ok := pm.reservedPorts[name]; ok {
+			if pm.isPortAvailable(ctx.Port) {
+				realPort = ctx.Port
+				pm.usedPorts[realPort] = portCtx
+				pm.reservedPorts[name] = portCtx
+				delete(pm.freePorts, realPort)
+				return
+			}
+		}
+	}
+
+	if port == 0 {
+		// get random port
+		count := 0
+		maxTryTimes := 5
+		for k, _ := range pm.freePorts {
+			count++
+			if count > maxTryTimes {
+				break
+			}
+			if pm.isPortAvailable(k) {
+				realPort = k
+				pm.usedPorts[realPort] = portCtx
+				pm.reservedPorts[name] = portCtx
+				delete(pm.freePorts, realPort)
+				break
+			}
+		}
+		if realPort == 0 {
+			err = ErrNoAvailablePort
+		}
+	} else {
+		// specified port
+		if _, ok = pm.freePorts[port]; ok {
+			if pm.isPortAvailable(port) {
+				realPort = port
+				pm.usedPorts[realPort] = portCtx
+				pm.reservedPorts[name] = portCtx
+				delete(pm.freePorts, realPort)
+			} else {
+				err = ErrPortUnAvailable
+			}
+		} else {
+			if _, ok = pm.usedPorts[port]; ok {
+				err = ErrPortAlreadyUsed
+			} else {
+				err = ErrPortNotAllowed
+			}
+		}
+	}
+	return
+}
+
+func (pm *PortManager) isPortAvailable(port int) bool {
+	if pm.netType == "udp" {
+		addr, err := net.ResolveUDPAddr("udp", fmt.Sprintf("%s:%d", pm.bindAddr, port))
+		if err != nil {
+			return false
+		}
+		l, err := net.ListenUDP("udp", addr)
+		if err != nil {
+			return false
+		}
+		l.Close()
+		return true
+	} else {
+		l, err := net.Listen(pm.netType, fmt.Sprintf("%s:%d", pm.bindAddr, port))
+		if err != nil {
+			return false
+		}
+		l.Close()
+		return true
+	}
+}
+
+func (pm *PortManager) Release(port int) {
+	pm.mu.Lock()
+	defer pm.mu.Unlock()
+	if ctx, ok := pm.usedPorts[port]; ok {
+		pm.freePorts[port] = struct{}{}
+		delete(pm.usedPorts, port)
+		ctx.Closed = true
+		ctx.UpdateTime = time.Now()
+	}
+}
+
+// Release reserved port if it isn't used in last 24 hours.
+func (pm *PortManager) cleanReservedPortsWorker() {
+	for {
+		time.Sleep(CleanReservedPortsInterval)
+		pm.mu.Lock()
+		for name, ctx := range pm.reservedPorts {
+			if ctx.Closed && time.Since(ctx.UpdateTime) > MaxPortReservedDuration {
+				delete(pm.reservedPorts, name)
+			}
+		}
+		pm.mu.Unlock()
+	}
+}