1 files changed, 41 insertions, 0 deletions
diff --git a/pkg/network/devices.go b/pkg/network/devices.go
new file mode 100644
index 000000000..26101b6f7
--- /dev/null
+++ b/pkg/network/devices.go
@@ -0,0 +1,41 @@
+package network
+
+import (
+	"fmt"
+	"github.com/containers/libpod/pkg/util"
+
+	"github.com/sirupsen/logrus"
+)
+
+// GetFreeDeviceName returns a device name that is unused; used when no network
+// name is provided by user
+func GetFreeDeviceName() (string, error) {
+	var (
+		deviceNum  uint
+		deviceName string
+	)
+	networkNames, err := GetNetworkNamesFromFileSystem()
+	if err != nil {
+		return "", err
+	}
+	liveNetworksNames, err := GetLiveNetworkNames()
+	if err != nil {
+		return "", err
+	}
+	for {
+		deviceName = fmt.Sprintf("%s%d", CNIDeviceName, deviceNum)
+		logrus.Debugf("checking if device name %s exists in other cni networks", deviceName)
+		if util.StringInSlice(deviceName, networkNames) {
+			deviceNum++
+			continue
+		}
+		logrus.Debugf("checking if device name %s exists in live networks", deviceName)
+		if !util.StringInSlice(deviceName, liveNetworksNames) {
+			break
+		}
+		// TODO Still need to check the bridge names for a conflict but I dont know
+		// how to get them yet!
+		deviceNum++
+	}
+	return deviceName, nil
+}