containerd/vendor/github.com/crosbymichael/cgroups/devices.go
Michael Crosby f36feb2ed4 Add prometheus container level metrics
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
2017-03-22 11:44:25 -07:00

74 lines
1.4 KiB
Go

package cgroups
import (
"fmt"
"io/ioutil"
"os"
"path/filepath"
specs "github.com/opencontainers/runtime-spec/specs-go"
)
const (
allowDeviceFile = "devices.allow"
denyDeviceFile = "devices.deny"
wildcard = -1
)
func NewDevices(root string) *devicesController {
return &devicesController{
root: filepath.Join(root, string(Devices)),
}
}
type devicesController struct {
root string
}
func (d *devicesController) Name() Name {
return Devices
}
func (d *devicesController) Path(path string) string {
return filepath.Join(d.root, path)
}
func (d *devicesController) Create(path string, resources *specs.LinuxResources) error {
if err := os.MkdirAll(d.Path(path), defaultDirPerm); err != nil {
return err
}
for _, device := range resources.Devices {
file := denyDeviceFile
if device.Allow {
file = allowDeviceFile
}
if err := ioutil.WriteFile(
filepath.Join(d.Path(path), file),
[]byte(deviceString(device)),
defaultFilePerm,
); err != nil {
return err
}
}
return nil
}
func (d *devicesController) Update(path string, resources *specs.LinuxResources) error {
return d.Create(path, resources)
}
func deviceString(device specs.LinuxDeviceCgroup) string {
return fmt.Sprintf("%c %s:%s %s",
&device.Type,
deviceNumber(device.Major),
deviceNumber(device.Minor),
&device.Access,
)
}
func deviceNumber(number *int64) string {
if number == nil || *number == wildcard {
return "*"
}
return fmt.Sprint(*number)
}