1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/vendor/github.com/Microsoft/hcsshim/preparelayer.go
Alexander Morozov f2614f2107 project: use vndr for vendoring
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
2016-11-03 15:31:46 -07:00

46 lines
1.4 KiB
Go

package hcsshim
import (
"sync"
"github.com/Sirupsen/logrus"
)
var prepareLayerLock sync.Mutex
// PrepareLayer finds a mounted read-write layer matching layerId and enables the
// the filesystem filter for use on that layer. This requires the paths to all
// parent layers, and is necessary in order to view or interact with the layer
// as an actual filesystem (reading and writing files, creating directories, etc).
// Disabling the filter must be done via UnprepareLayer.
func PrepareLayer(info DriverInfo, layerId string, parentLayerPaths []string) error {
title := "hcsshim::PrepareLayer "
logrus.Debugf(title+"flavour %d layerId %s", info.Flavour, layerId)
// Generate layer descriptors
layers, err := layerPathsToDescriptors(parentLayerPaths)
if err != nil {
return err
}
// Convert info to API calling convention
infop, err := convertDriverInfo(info)
if err != nil {
logrus.Error(err)
return err
}
// This lock is a temporary workaround for a Windows bug. Only allowing one
// call to prepareLayer at a time vastly reduces the chance of a timeout.
prepareLayerLock.Lock()
defer prepareLayerLock.Unlock()
err = prepareLayer(&infop, layerId, layers)
if err != nil {
err = makeErrorf(err, title, "layerId=%s flavour=%d", layerId, info.Flavour)
logrus.Error(err)
return err
}
logrus.Debugf(title+"succeeded flavour=%d layerId=%s", info.Flavour, layerId)
return nil
}