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authorMatthew Heon <matthew.heon@gmail.com>2017-11-01 11:24:59 -0400
committerMatthew Heon <matthew.heon@gmail.com>2017-11-01 11:24:59 -0400
commita031b83a09a8628435317a03f199cdc18b78262f (patch)
treebc017a96769ce6de33745b8b0b1304ccf38e9df0 /vendor/github.com/vishvananda/netns/netns.go
parent2b74391cd5281f6fdf391ff8ad50fd1490f6bf89 (diff)
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Initial checkin from CRI-O repo
Signed-off-by: Matthew Heon <matthew.heon@gmail.com>
Diffstat (limited to 'vendor/github.com/vishvananda/netns/netns.go')
-rw-r--r--vendor/github.com/vishvananda/netns/netns.go80
1 files changed, 80 insertions, 0 deletions
diff --git a/vendor/github.com/vishvananda/netns/netns.go b/vendor/github.com/vishvananda/netns/netns.go
new file mode 100644
index 000000000..dd2f21570
--- /dev/null
+++ b/vendor/github.com/vishvananda/netns/netns.go
@@ -0,0 +1,80 @@
+// Package netns allows ultra-simple network namespace handling. NsHandles
+// can be retrieved and set. Note that the current namespace is thread
+// local so actions that set and reset namespaces should use LockOSThread
+// to make sure the namespace doesn't change due to a goroutine switch.
+// It is best to close NsHandles when you are done with them. This can be
+// accomplished via a `defer ns.Close()` on the handle. Changing namespaces
+// requires elevated privileges, so in most cases this code needs to be run
+// as root.
+package netns
+
+import (
+ "fmt"
+ "syscall"
+)
+
+// NsHandle is a handle to a network namespace. It can be cast directly
+// to an int and used as a file descriptor.
+type NsHandle int
+
+// Equal determines if two network handles refer to the same network
+// namespace. This is done by comparing the device and inode that the
+// file descriptors point to.
+func (ns NsHandle) Equal(other NsHandle) bool {
+ if ns == other {
+ return true
+ }
+ var s1, s2 syscall.Stat_t
+ if err := syscall.Fstat(int(ns), &s1); err != nil {
+ return false
+ }
+ if err := syscall.Fstat(int(other), &s2); err != nil {
+ return false
+ }
+ return (s1.Dev == s2.Dev) && (s1.Ino == s2.Ino)
+}
+
+// String shows the file descriptor number and its dev and inode.
+func (ns NsHandle) String() string {
+ var s syscall.Stat_t
+ if ns == -1 {
+ return "NS(None)"
+ }
+ if err := syscall.Fstat(int(ns), &s); err != nil {
+ return fmt.Sprintf("NS(%d: unknown)", ns)
+ }
+ return fmt.Sprintf("NS(%d: %d, %d)", ns, s.Dev, s.Ino)
+}
+
+// UniqueId returns a string which uniquely identifies the namespace
+// associated with the network handle.
+func (ns NsHandle) UniqueId() string {
+ var s syscall.Stat_t
+ if ns == -1 {
+ return "NS(none)"
+ }
+ if err := syscall.Fstat(int(ns), &s); err != nil {
+ return "NS(unknown)"
+ }
+ return fmt.Sprintf("NS(%d:%d)", s.Dev, s.Ino)
+}
+
+// IsOpen returns true if Close() has not been called.
+func (ns NsHandle) IsOpen() bool {
+ return ns != -1
+}
+
+// Close closes the NsHandle and resets its file descriptor to -1.
+// It is not safe to use an NsHandle after Close() is called.
+func (ns *NsHandle) Close() error {
+ if err := syscall.Close(int(*ns)); err != nil {
+ return err
+ }
+ (*ns) = -1
+ return nil
+}
+
+// None gets an empty (closed) NsHandle.
+func None() NsHandle {
+ return NsHandle(-1)
+}