Repository: opencontainers/runc
File: libcontainer/container_linux.go (Go)

Code before:
		veth := new(criurpc.CriuVethPair)
		veth.IfOut = proto.String(i.HostInterfaceName)
		veth.IfIn = proto.String(i.ContainerInterfaceName)
		req.Opts.Veths = append(req.Opts.Veths, veth)
	}
}

// makeCriuRestoreMountpoints makes the actual mountpoints for the
// restore using CRIU. This function is inspired from the code in
// rootfs_linux.go
func (c *Container) makeCriuRestoreMountpoints(m *configs.Mount) error {
	switch m.Device {
	case "cgroup":
		// No mount point(s) need to be created:
		//
		// * for v1, mount points are saved by CRIU because
		//   /sys/fs/cgroup is a tmpfs mount
		//
		// * for v2, /sys/fs/cgroup is a real mount, but
		//   the mountpoint appears as soon as /sys is mounted
		return nil
	case "bind":
		// The prepareBindMount() function checks if source
		// exists. So it cannot be used for other filesystem types.
		// TODO: pass srcFD? Not sure if criu is impacted by issue #2484.
		if err := prepareBindMount(mountEntry{Mount: m, srcFD: -1}, c.config.Rootfs); err != nil {
			return err
		}
	default:
		// for all other filesystems just create the mountpoints
		dest, err := securejoin.SecureJoin(c.config.Rootfs, m.Destination)
		if err != nil {
			return err
		}
		if err := checkProcMount(c.config.Rootfs, dest, ""); err != nil {
			return err
		}
		if err := os.MkdirAll(dest, 0o755); err != nil {
			return err
		}
	}
	return nil
}

// isPathInPrefixList is a small function for CRIU restore to make sure
// mountpoints, which are on a tmpfs, are not created in the roofs
func isPathInPrefixList(path string, prefix []string) bool {
	for _, p := range prefix {
		if strings.HasPrefix(path, p+"/") {
			return true
		}

Review comment (refactor):
What I don't like about this approach is, with the string we can use the default value ("") to see there's no srcfd. With int, we have to use `-1` everywhere, which is kind of ugly.

I'm on the verge of stating that in all the usage scenarios we can't possibly have `0` for `srcFD`, and thus use `0` as "no srcfd is set". This will simplify the code (but break it, if we'll ever have `0` as srcid).

Code after:
		veth := new(criurpc.CriuVethPair)
		veth.IfOut = proto.String(i.HostInterfaceName)
		veth.IfIn = proto.String(i.ContainerInterfaceName)
		req.Opts.Veths = append(req.Opts.Veths, veth)
	}
}

// makeCriuRestoreMountpoints makes the actual mountpoints for the
// restore using CRIU. This function is inspired from the code in
// rootfs_linux.go
func (c *Container) makeCriuRestoreMountpoints(m *configs.Mount) error {
	switch m.Device {
	case "cgroup":
		// No mount point(s) need to be created:
		//
		// * for v1, mount points are saved by CRIU because
		//   /sys/fs/cgroup is a tmpfs mount
		//
		// * for v2, /sys/fs/cgroup is a real mount, but
		//   the mountpoint appears as soon as /sys is mounted
		return nil
	case "bind":
		// The prepareBindMount() function checks if source
		// exists. So it cannot be used for other filesystem types.
		// TODO: pass srcFD? Not sure if criu is impacted by issue #2484.
		if err := prepareBindMount(mountEntry{Mount: m}, c.config.Rootfs); err != nil {
			return err
		}
	default:
		// for all other filesystems just create the mountpoints
		dest, err := securejoin.SecureJoin(c.config.Rootfs, m.Destination)
		if err != nil {
			return err
		}
		if err := checkProcMount(c.config.Rootfs, dest, ""); err != nil {
			return err
		}
		if err := os.MkdirAll(dest, 0o755); err != nil {
			return err
		}
	}
	return nil
}

// isPathInPrefixList is a small function for CRIU restore to make sure
// mountpoints, which are on a tmpfs, are not created in the roofs
func isPathInPrefixList(path string, prefix []string) bool {
	for _, p := range prefix {
		if strings.HasPrefix(path, p+"/") {
			return true
		}