Documentation
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Index ¶
- Constants
- Variables
- func Annotations(labels []string) (bundle string, userAnnotations map[string]string)
- func CleanPath(path string) string
- func CloseExecFrom(minFd int) error
- func EnsureProcHandle(fh *os.File) error
- func ExitStatus(status unix.WaitStatus) int
- func NewSockPair(name string) (parent, child *os.File, err error)
- func RecvFile(socket *os.File) (_ *os.File, Err error)
- func SearchLabels(labels []string, key string) (string, bool)
- func SendFile(socket *os.File, file *os.File) error
- func SendRawFd(socket *os.File, msg string, fd uintptr) error
- func WithProcfd(root, unsafePath string, fn func(procfd string) error) error
- func WriteJSON(w io.Writer, v interface{}) error
- type ProcThreadSelfCloser
Constants ¶
const MaxNameLen = 4096
MaxNameLen is the maximum length of the name of a file descriptor being sent using SendFile. The name of the file handle returned by RecvFile will never be larger than this value.
Variables ¶
var NativeEndian binary.ByteOrder
NativeEndian is the native byte order of the host system.
Functions ¶
func Annotations ¶
Annotations returns the bundle path and user defined annotations from the libcontainer state. We need to remove the bundle because that is a label added by libcontainer.
func CleanPath ¶
CleanPath makes a path safe for use with filepath.Join. This is done by not only cleaning the path, but also (if the path is relative) adding a leading '/' and cleaning it (then removing the leading '/'). This ensures that a path resulting from prepending another path will always resolve to lexically be a subdirectory of the prefixed path. This is all done lexically, so paths that include symlinks won't be safe as a result of using CleanPath.
func CloseExecFrom ¶
CloseExecFrom applies O_CLOEXEC to all file descriptors currently open for the process (except for those below the given fd value).
func EnsureProcHandle ¶
EnsureProcHandle returns whether or not the given file handle is on procfs.
func ExitStatus ¶
func ExitStatus(status unix.WaitStatus) int
ExitStatus returns the correct exit status for a process based on if it was signaled or exited cleanly
func NewSockPair ¶
NewSockPair returns a new SOCK_STREAM unix socket pair.
func RecvFile ¶
RecvFile waits for a file descriptor to be sent over the given AF_UNIX socket. The file name of the remote file descriptor will be recreated locally (it is sent as non-auxiliary data in the same payload).
func SearchLabels ¶
SearchLabels searches through a list of key=value pairs for a given key, returning its value, and the binary flag telling whether the key exist.
func SendFile ¶
SendFile sends a file over the given AF_UNIX socket. file.Name() is also included so that if the other end uses RecvFile, the file will have the same name information.
func WithProcfd ¶
WithProcfd runs the passed closure with a procfd path (/proc/self/fd/...) corresponding to the unsafePath resolved within the root. Before passing the fd, this path is verified to have been inside the root -- so operating on it through the passed fdpath should be safe. Do not access this path through the original path strings, and do not attempt to use the pathname outside of the passed closure (the file handle will be freed once the closure returns).
func WriteJSON ¶
WriteJSON writes the provided struct v to w using standard json marshaling without a trailing newline. This is used instead of json.Encoder because there might be a problem in json decoder in some cases, see: https://github.com/docker/docker/issues/14203#issuecomment-174177790
Types ¶
type ProcThreadSelfCloser ¶
type ProcThreadSelfCloser func()
func ProcThreadSelf ¶
func ProcThreadSelf(subpath string) (string, ProcThreadSelfCloser)
ProcThreadSelf returns a string that is equivalent to /proc/thread-self/<subpath>, with a graceful fallback on older kernels where /proc/thread-self doesn't exist. This method DOES NOT use SecureJoin, meaning that the passed string needs to be trusted. The caller _must_ call the returned procThreadSelfCloser function (which is runtime.UnlockOSThread) *only once* after it has finished using the returned path string.
Source Files