74 lines
1.4 KiB
Go
74 lines
1.4 KiB
Go
package graphdriver
|
|
|
|
import (
|
|
"fmt"
|
|
"github.com/dotcloud/docker/archive"
|
|
)
|
|
|
|
type InitFunc func(root string) (Driver, error)
|
|
|
|
// FIXME: this is a temporary placeholder for archive.Change
|
|
// (to be merged from master)
|
|
type Change interface {
|
|
}
|
|
|
|
type Driver interface {
|
|
Create(id, parent string) error
|
|
Remove(id string) error
|
|
|
|
Get(id string) (dir string, err error)
|
|
|
|
Diff(id string) (archive.Archive, error)
|
|
DiffSize(id string) (bytes int64, err error)
|
|
Changes(id string) ([]Change, error)
|
|
|
|
Cleanup() error
|
|
}
|
|
|
|
var (
|
|
// All registred drivers
|
|
drivers map[string]InitFunc
|
|
// Slice of drivers that should be used in an order
|
|
priority = []string{
|
|
"aufs",
|
|
"devicemapper",
|
|
}
|
|
)
|
|
|
|
func init() {
|
|
drivers = make(map[string]InitFunc)
|
|
}
|
|
|
|
func Register(name string, initFunc InitFunc) error {
|
|
if _, exists := drivers[name]; exists {
|
|
return fmt.Errorf("Name already registered %s", name)
|
|
}
|
|
drivers[name] = initFunc
|
|
|
|
return nil
|
|
}
|
|
|
|
func New(root string) (Driver, error) {
|
|
var driver Driver
|
|
var lastError error
|
|
// Check for priority drivers first
|
|
for _, name := range priority {
|
|
if initFunc, exists := drivers[name]; exists {
|
|
driver, lastError = initFunc(root)
|
|
if lastError != nil {
|
|
continue
|
|
}
|
|
return driver, nil
|
|
}
|
|
}
|
|
|
|
// Check all registered drivers if no priority driver is found
|
|
for _, initFunc := range drivers {
|
|
driver, lastError = initFunc(root)
|
|
if lastError != nil {
|
|
continue
|
|
}
|
|
return driver, nil
|
|
}
|
|
return nil, lastError
|
|
}
|