k3s/vendor/github.com/Microsoft/hcsshim/internal/cni/registry.go
2019-09-30 16:25:17 -07:00

111 lines
2.6 KiB
Go

package cni
import (
"errors"
"github.com/Microsoft/go-winio/pkg/guid"
"github.com/Microsoft/hcsshim/internal/regstate"
)
const (
cniRoot = "cni"
cniKey = "cfg"
)
// PersistedNamespaceConfig is the registry version of the `NamespaceID` to UVM
// map.
type PersistedNamespaceConfig struct {
namespaceID string
stored bool
ContainerID string
HostUniqueID guid.GUID
}
// NewPersistedNamespaceConfig creates an in-memory namespace config that can be
// persisted to the registry.
func NewPersistedNamespaceConfig(namespaceID, containerID string, containerHostUniqueID guid.GUID) *PersistedNamespaceConfig {
return &PersistedNamespaceConfig{
namespaceID: namespaceID,
ContainerID: containerID,
HostUniqueID: containerHostUniqueID,
}
}
// LoadPersistedNamespaceConfig loads a persisted config from the registry that matches
// `namespaceID`. If not found returns `regstate.NotFoundError`
func LoadPersistedNamespaceConfig(namespaceID string) (*PersistedNamespaceConfig, error) {
sk, err := regstate.Open(cniRoot, false)
if err != nil {
return nil, err
}
defer sk.Close()
pnc := PersistedNamespaceConfig{
namespaceID: namespaceID,
stored: true,
}
if err := sk.Get(namespaceID, cniKey, &pnc); err != nil {
return nil, err
}
return &pnc, nil
}
// Store stores or updates the in-memory config to its registry state. If the
// store failes returns the store error.
func (pnc *PersistedNamespaceConfig) Store() error {
if pnc.namespaceID == "" {
return errors.New("invalid namespaceID ''")
}
if pnc.ContainerID == "" {
return errors.New("invalid containerID ''")
}
empty := guid.GUID{}
if pnc.HostUniqueID == empty {
return errors.New("invalid containerHostUniqueID 'empy'")
}
sk, err := regstate.Open(cniRoot, false)
if err != nil {
return err
}
defer sk.Close()
if pnc.stored {
if err := sk.Set(pnc.namespaceID, cniKey, pnc); err != nil {
return err
}
} else {
if err := sk.Create(pnc.namespaceID, cniKey, pnc); err != nil {
return err
}
}
pnc.stored = true
return nil
}
// Remove removes any persisted state associated with this config. If the config
// is not found in the registery `Remove` returns no error.
func (pnc *PersistedNamespaceConfig) Remove() error {
if pnc.stored {
sk, err := regstate.Open(cniRoot, false)
if err != nil {
if regstate.IsNotFoundError(err) {
pnc.stored = false
return nil
}
return err
}
defer sk.Close()
if err := sk.Remove(pnc.namespaceID); err != nil {
if regstate.IsNotFoundError(err) {
pnc.stored = false
return nil
}
return err
}
}
pnc.stored = false
return nil
}