56 lines
1.5 KiB
Go
56 lines
1.5 KiB
Go
|
package hcsshim
|
||
|
|
|
||
|
|
import (
|
||
|
|
"syscall"
|
||
|
|
|
||
|
|
"github.com/Sirupsen/logrus"
|
||
|
|
)
|
||
|
|
|
||
|
|
// GetLayerMountPath will look for a mounted layer with the given id and return
|
||
|
|
// the path at which that layer can be accessed. This path may be a volume path
|
||
|
|
// if the layer is a mounted read-write layer, otherwise it is expected to be the
|
||
|
|
// folder path at which the layer is stored.
|
||
|
|
func GetLayerMountPath(info DriverInfo, id string) (string, error) {
|
||
|
|
title := "hcsshim::GetLayerMountPath "
|
||
|
|
logrus.Debugf(title+"Flavour %d ID %s", info.Flavour, id)
|
||
|
|
|
||
|
|
// Convert info to API calling convention
|
||
|
|
infop, err := convertDriverInfo(info)
|
||
|
|
if err != nil {
|
||
|
|
logrus.Error(err)
|
||
|
|
return "", err
|
||
|
|
}
|
||
|
|
|
||
|
|
var mountPathLength uintptr
|
||
|
|
mountPathLength = 0
|
||
|
|
|
||
|
|
// Call the procedure itself.
|
||
|
|
logrus.Debugf("Calling proc (1)")
|
||
|
|
err = getLayerMountPath(&infop, id, &mountPathLength, nil)
|
||
|
|
if err != nil {
|
||
|
|
err = makeErrorf(err, title, "(first call) id=%s flavour=%d", id, info.Flavour)
|
||
|
|
logrus.Error(err)
|
||
|
|
return "", err
|
||
|
|
}
|
||
|
|
|
||
|
|
// Allocate a mount path of the returned length.
|
||
|
|
if mountPathLength == 0 {
|
||
|
|
return "", nil
|
||
|
|
}
|
||
|
|
mountPathp := make([]uint16, mountPathLength)
|
||
|
|
mountPathp[0] = 0
|
||
|
|
|
||
|
|
// Call the procedure again
|
||
|
|
logrus.Debugf("Calling proc (2)")
|
||
|
|
err = getLayerMountPath(&infop, id, &mountPathLength, &mountPathp[0])
|
||
|
|
if err != nil {
|
||
|
|
err = makeErrorf(err, title, "(second call) id=%s flavour=%d", id, info.Flavour)
|
||
|
|
logrus.Error(err)
|
||
|
|
return "", err
|
||
|
|
}
|
||
|
|
|
||
|
|
path := syscall.UTF16ToString(mountPathp[0:])
|
||
|
|
logrus.Debugf(title+"succeeded flavour=%d id=%s path=%s", info.Flavour, id, path)
|
||
|
|
return path, nil
|
||
|
|
}
|