pkg/libcontainer/cgroups/fs/utils.go
Michael Crosby b30f280d2f Move cgroups package into libcontainer
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
2014-05-14 15:21:44 -07:00

40 lines
1 KiB
Go

package fs
import (
"errors"
"fmt"
"io/ioutil"
"path/filepath"
"strconv"
"strings"
)
var (
ErrNotSupportStat = errors.New("stats are not supported for subsystem")
ErrNotValidFormat = errors.New("line is not a valid key value format")
)
// Parses a cgroup param and returns as name, value
// i.e. "io_service_bytes 1234" will return as io_service_bytes, 1234
func getCgroupParamKeyValue(t string) (string, float64, error) {
parts := strings.Fields(t)
switch len(parts) {
case 2:
value, err := strconv.ParseFloat(parts[1], 64)
if err != nil {
return "", 0.0, fmt.Errorf("Unable to convert param value to float: %s", err)
}
return parts[0], value, nil
default:
return "", 0.0, ErrNotValidFormat
}
}
// Gets a single float64 value from the specified cgroup file.
func getCgroupParamFloat64(cgroupPath, cgroupFile string) (float64, error) {
contents, err := ioutil.ReadFile(filepath.Join(cgroupPath, cgroupFile))
if err != nil {
return -1.0, err
}
return strconv.ParseFloat(strings.TrimSpace(string(contents)), 64)
}