dotcloud/docker

package cnmallocator

import (
    "context"
    "fmt"
    "net/netip"
    "strconv"
    "strings"

    "github.com/containerd/log"
    "github.com/docker/docker/libnetwork/ipamapi"
    "github.com/docker/docker/libnetwork/ipams"
    "github.com/docker/docker/libnetwork/ipamutils"
    "github.com/moby/swarmkit/v2/manager/allocator/networkallocator"
)

func initIPAMDrivers(r ipamapi.Registerer, netConfig *networkallocator.Config) error {
    var addressPool []*ipamutils.NetworkToSplit
    var str strings.Builder
    str.WriteString("Subnetlist - ")
    // Extract defaultAddrPool param info and construct ipamutils.NetworkToSplit
    // from the info. We will be using it to call Libnetwork API
    // We also need to log new address pool info whenever swarm init
    // happens with default address pool option
    if netConfig != nil {
        for _, p := range netConfig.DefaultAddrPool {
            base, err := netip.ParsePrefix(p)
            if err != nil {
                return fmt.Errorf("invalid prefix %q: %w", p, err)
            }
            addressPool = append(addressPool, &ipamutils.NetworkToSplit{
                Base: base,
                Size: int(netConfig.SubnetSize),
            })
            str.WriteString(p + ",")
        }
        str.WriteString(": Size ")
        str.WriteString(strconv.Itoa(int(netConfig.SubnetSize)))

    }

    if len(addressPool) > 0 {
        log.G(context.TODO()).Info("Swarm initialized global default address pool to: " + str.String())
    }

    if err := ipams.Register(r, nil, nil, addressPool); err != nil {
        return err
    }

    return nil
}