install go2rtc on bob

installs_on_host/go2rtc/pkg/xnet/net.go

@@ -0,0 +1,64 @@
+package xnet
+
+import (
+	"net"
+	"strconv"
+)
+
+// Docker has common docker addresses (class B):
+// https://en.wikipedia.org/wiki/Private_network
+// - docker0 172.17.0.1/16
+// - br-xxxx 172.18.0.1/16
+// - hassio  172.30.32.1/23
+var Docker = net.IPNet{
+	IP:   []byte{172, 16, 0, 0},
+	Mask: []byte{255, 240, 0, 0},
+}
+
+// ParseUnspecifiedPort will return port if address is unspecified
+// ex. ":8555" or "0.0.0.0:8555"
+func ParseUnspecifiedPort(address string) int {
+	host, port, err := net.SplitHostPort(address)
+	if err != nil {
+		return 0
+	}
+
+	if host != "" && host != "0.0.0.0" && host != "[::]" {
+		return 0
+	}
+
+	i, _ := strconv.Atoi(port)
+	return i
+}
+
+func IPNets(ipFilter func(ip net.IP) bool) ([]*net.IPNet, error) {
+	ifaces, err := net.Interfaces()
+	if err != nil {
+		return nil, err
+	}
+
+	var nets []*net.IPNet
+
+	for _, iface := range ifaces {
+		if iface.Flags&net.FlagUp == 0 || iface.Flags&net.FlagLoopback != 0 {
+			continue
+		}
+
+		addrs, _ := iface.Addrs() // range on nil slice is OK
+		for _, addr := range addrs {
+			switch v := addr.(type) {
+			case *net.IPNet:
+				ip := v.IP.To4()
+				if ip == nil {
+					continue
+				}
+				if ipFilter != nil && !ipFilter(ip) {
+					continue
+				}
+				nets = append(nets, v)
+			}
+		}
+	}
+
+	return nets, nil
+}