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Diffstat (limited to 'vendor/github.com/containernetworking/plugins/pkg/utils/sysctl/sysctl_linux.go')
-rw-r--r--vendor/github.com/containernetworking/plugins/pkg/utils/sysctl/sysctl_linux.go80
1 files changed, 80 insertions, 0 deletions
diff --git a/vendor/github.com/containernetworking/plugins/pkg/utils/sysctl/sysctl_linux.go b/vendor/github.com/containernetworking/plugins/pkg/utils/sysctl/sysctl_linux.go
new file mode 100644
index 000000000..7ee47e1ce
--- /dev/null
+++ b/vendor/github.com/containernetworking/plugins/pkg/utils/sysctl/sysctl_linux.go
@@ -0,0 +1,80 @@
+// Copyright 2016 CNI authors
+//
+// 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 sysctl
+
+import (
+ "fmt"
+ "io/ioutil"
+ "path/filepath"
+ "strings"
+)
+
+// Sysctl provides a method to set/get values from /proc/sys - in linux systems
+// new interface to set/get values of variables formerly handled by sysctl syscall
+// If optional `params` have only one string value - this function will
+// set this value into corresponding sysctl variable
+func Sysctl(name string, params ...string) (string, error) {
+ if len(params) > 1 {
+ return "", fmt.Errorf("unexcepted additional parameters")
+ } else if len(params) == 1 {
+ return setSysctl(name, params[0])
+ }
+ return getSysctl(name)
+}
+
+func getSysctl(name string) (string, error) {
+ fullName := filepath.Join("/proc/sys", toNormalName(name))
+ fullName = filepath.Clean(fullName)
+ data, err := ioutil.ReadFile(fullName)
+ if err != nil {
+ return "", err
+ }
+
+ return string(data[:len(data)-1]), nil
+}
+
+func setSysctl(name, value string) (string, error) {
+ fullName := filepath.Join("/proc/sys", toNormalName(name))
+ fullName = filepath.Clean(fullName)
+ if err := ioutil.WriteFile(fullName, []byte(value), 0644); err != nil {
+ return "", err
+ }
+
+ return getSysctl(name)
+}
+
+// Normalize names by using slash as separator
+// Sysctl names can use dots or slashes as separator:
+// - if dots are used, dots and slashes are interchanged.
+// - if slashes are used, slashes and dots are left intact.
+// Separator in use is determined by first occurrence.
+func toNormalName(name string) string {
+ interchange := false
+ for _, c := range name {
+ if c == '.' {
+ interchange = true
+ break
+ }
+ if c == '/' {
+ break
+ }
+ }
+
+ if interchange {
+ r := strings.NewReplacer(".", "/", "/", ".")
+ return r.Replace(name)
+ }
+ return name
+}