Documentation
¶
Overview ¶
Package msgqueue implements System V message queues.
Index ¶
- type Blocker
- type Message
- func (e *Message) Next() *Message
- func (e *Message) Prev() *Message
- func (e *Message) SetNext(elem *Message)
- func (e *Message) SetPrev(elem *Message)
- func (m *Message) StateFields() []string
- func (m *Message) StateLoad(stateSourceObject state.Source)
- func (m *Message) StateSave(stateSinkObject state.Sink)
- func (m *Message) StateTypeName() string
- type Queue
- func (q *Queue) Copy(mType int64) (*Message, error)
- func (q *Queue) Destroy()
- func (q *Queue) ID() ipc.ID
- func (q *Queue) Lock()
- func (q *Queue) Object() *ipc.Object
- func (q *Queue) Receive(ctx context.Context, b Blocker, mType int64, maxSize int64, ...) (*Message, error)
- func (q *Queue) Send(ctx context.Context, m Message, b Blocker, wait bool, pid int32) error
- func (q *Queue) Set(ctx context.Context, ds *linux.MsqidDS) error
- func (q *Queue) Stat(ctx context.Context) (*linux.MsqidDS, error)
- func (q *Queue) StatAny(ctx context.Context) (*linux.MsqidDS, error)
- func (q *Queue) StateFields() []string
- func (q *Queue) StateLoad(stateSourceObject state.Source)
- func (q *Queue) StateSave(stateSinkObject state.Sink)
- func (q *Queue) StateTypeName() string
- func (q *Queue) Unlock()
- type Registry
- func (r *Registry) FindByID(id ipc.ID) (*Queue, error)
- func (r *Registry) FindOrCreate(ctx context.Context, key ipc.Key, mode linux.FileMode, ...) (*Queue, error)
- func (r *Registry) IPCInfo(ctx context.Context) *linux.MsgInfo
- func (r *Registry) MsgInfo(ctx context.Context) *linux.MsgInfo
- func (r *Registry) Remove(id ipc.ID, creds *auth.Credentials) error
- func (r *Registry) StateFields() []string
- func (r *Registry) StateLoad(stateSourceObject state.Source)
- func (r *Registry) StateSave(stateSinkObject state.Sink)
- func (r *Registry) StateTypeName() string
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Blocker ¶
type Blocker interface {
Block(C <-chan struct{}) error
}
Blocker is used for blocking Queue.Send, and Queue.Receive calls that serves as an abstracted version of kernel.Task. kernel.Task is not directly used to prevent circular dependencies.
type Message ¶
type Message struct {
// Type is an integer representing the type of the sent message.
Type int64
// Text is an untyped block of memory.
Text []byte
// Size is the size of Text.
Size uint64
// contains filtered or unexported fields
}
Message represents a message exchanged through a Queue via msgsnd(2) and msgrcv(2).
+stateify savable
func (*Message) Next ¶
func (e *Message) Next() *Message
Next returns the entry that follows e in the list.
func (*Message) Prev ¶
func (e *Message) Prev() *Message
Prev returns the entry that precedes e in the list.
func (*Message) SetNext ¶
func (e *Message) SetNext(elem *Message)
SetNext assigns 'entry' as the entry that follows e in the list.
func (*Message) SetPrev ¶
func (e *Message) SetPrev(elem *Message)
SetPrev assigns 'entry' as the entry that precedes e in the list.
func (*Message) StateFields ¶
func (*Message) StateTypeName ¶
type Queue ¶
type Queue struct {
// contains filtered or unexported fields
}
Queue represents a SysV message queue, described by sysvipc(7).
+stateify savable
func (*Queue) Copy ¶
Copy copies a message from the queue without deleting it. If no message exists, an error is returned. See msgrcv(MSG_COPY).
func (*Queue) Receive ¶
func (q *Queue) Receive(ctx context.Context, b Blocker, mType int64, maxSize int64, wait, truncate, except bool, pid int32) (*Message, error)
Receive removes a message from the queue and returns it. See msgrcv(2).
func (*Queue) Send ¶
Send appends a message to the message queue, and returns an error if sending fails. See msgsnd(2).
func (*Queue) Stat ¶
Stat returns a MsqidDS object filled with information about the queue. See msgctl(IPC_STAT) and msgctl(MSG_STAT).
func (*Queue) StatAny ¶
StatAny is similar to Queue.Stat, but doesn't require read permission. See msgctl(MSG_STAT_ANY).
func (*Queue) StateFields ¶
func (*Queue) StateTypeName ¶
type Registry ¶
type Registry struct {
// contains filtered or unexported fields
}
Registry contains a set of message queues that can be referenced using keys or IDs.
+stateify savable
func NewRegistry ¶
func NewRegistry(userNS *auth.UserNamespace) *Registry
NewRegistry returns a new Registry ready to be used.
func (*Registry) FindByID ¶
FindByID returns the queue with the specified ID and an error if the ID doesn't exist.
func (*Registry) FindOrCreate ¶
func (r *Registry) FindOrCreate(ctx context.Context, key ipc.Key, mode linux.FileMode, private, create, exclusive bool) (*Queue, error)
FindOrCreate creates a new message queue or returns an existing one. See msgget(2).
func (*Registry) IPCInfo ¶
IPCInfo reports global parameters for message queues. See msgctl(IPC_INFO).
func (*Registry) MsgInfo ¶
MsgInfo reports global parameters for message queues. See msgctl(MSG_INFO).
func (*Registry) Remove ¶
Remove removes the queue with specified ID. All waiters (readers and writers) and writers will be awakened and fail. Remove will return an error if the ID is invalid, or the the user doesn't have privileges.
Source Files