Files
kata-containers/virtcontainers/utils.go
Samuel Ortiz 24eff72d82 virtcontainers: Initial import
This is a virtcontainers 1.0.8 import into Kata Containers runtime.

virtcontainers is a Go library designed to manage hardware virtualized
pods and containers. It is the core Clear Containers framework and will
become the core Kata Containers framework, as discussed at
https://github.com/kata-containers/runtime/issues/33

Some more more pointers:

virtcontainers README, including some design and architecure notes:
https://github.com/containers/virtcontainers/blob/master/README.md

virtcontainers 1.0 API:
https://github.com/containers/virtcontainers/blob/master/documentation/api/1.0/api.md

Fixes #40

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2018-03-13 00:49:46 +01:00

114 lines
2.4 KiB
Go

//
// Copyright (c) 2017 Intel Corporation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
package virtcontainers
import (
"crypto/rand"
"fmt"
"os"
"os/exec"
)
const cpBinaryName = "cp"
const fileMode0755 = os.FileMode(0755)
func fileCopy(srcPath, dstPath string) error {
if srcPath == "" {
return fmt.Errorf("Source path cannot be empty")
}
if dstPath == "" {
return fmt.Errorf("Destination path cannot be empty")
}
binPath, err := exec.LookPath(cpBinaryName)
if err != nil {
return err
}
cmd := exec.Command(binPath, srcPath, dstPath)
return cmd.Run()
}
func generateRandomBytes(n int) ([]byte, error) {
b := make([]byte, n)
_, err := rand.Read(b)
if err != nil {
return nil, err
}
return b, nil
}
func reverseString(s string) string {
r := []rune(s)
length := len(r)
for i, j := 0, length-1; i < length/2; i, j = i+1, j-1 {
r[i], r[j] = r[j], r[i]
}
return string(r)
}
func cleanupFds(fds []*os.File, numFds int) {
maxFds := len(fds)
if numFds < maxFds {
maxFds = numFds
}
for i := 0; i < maxFds; i++ {
_ = fds[i].Close()
}
}
// writeToFile opens a file in write only mode and writes bytes to it
func writeToFile(path string, data []byte) error {
f, err := os.OpenFile(path, os.O_WRONLY, fileMode0755)
if err != nil {
return err
}
defer f.Close()
if _, err := f.Write(data); err != nil {
return err
}
return nil
}
// ConstraintsToVCPUs converts CPU quota and period to vCPUs
func ConstraintsToVCPUs(quota int64, period uint64) uint {
if quota != 0 && period != 0 {
// Use some math magic to round up to the nearest whole vCPU
// (that is, a partial part of a quota request ends up assigning
// a whole vCPU, for instance, a request of 1.5 'cpu quotas'
// will give 2 vCPUs).
// This also has the side effect that we will always allocate
// at least 1 vCPU.
return uint((uint64(quota) + (period - 1)) / period)
}
return 0
}