multisocketsink

multisocketsink — Send data to multiple sockets

Properties

gint buffers-max Read / Write
gint buffers-min Read / Write
guint buffers-queued Read
gint buffers-soft-max Read / Write
GstFormat burst-format Read / Write
guint64 burst-value Read / Write
gint bytes-min Read / Write
guint64 bytes-served Read
guint64 bytes-to-serve Read
gboolean handle-read Read / Write
guint num-sockets Read
gint qos-dscp Read / Write
GstMultiSocketSinkRecoverPolicy recover-policy Read / Write
gboolean resend-streamheader Read / Write
GstMultiSocketSinkSyncMethod sync-method Read / Write
gint64 time-min Read / Write
guint64 timeout Read / Write
GstFormat unit-type Read / Write
gint64 units-max Read / Write
gint64 units-soft-max Read / Write

Signals

void add Action
void add-full Action
void clear Action
void client-added Run Last
void client-removed Run Last
void client-socket-removed Run Last
GstStructure* get-stats Action
void remove Action
void remove-flush Action
void client-handle-removed Run Last

Types and Values

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GstObject
            ╰── GstElement
                ╰── GstBaseSink
                    ╰── GstMultiHandleSink
                        ╰── GstMultiSocketSink
                            ╰── GstTCPServerSink

Description

This plugin writes incoming data to a set of file descriptors. The file descriptors can be added to multisocketsink by emitting the “add” signal. For each descriptor added, the “client-added” signal will be called.

As of version 0.10.8, a client can also be added with the “add-full” signal that allows for more control over what and how much data a client initially receives.

Clients can be removed from multisocketsink by emitting the “remove” signal. For each descriptor removed, the “client-removed” signal will be called. The “client-removed” signal can also be fired when multisocketsink decides that a client is not active anymore or, depending on the value of the “recover-policy” property, if the client is reading too slowly. In all cases, multisocketsink will never close a file descriptor itself. The user of multisocketsink is responsible for closing all file descriptors. This can for example be done in response to the “client-fd-removed” signal. Note that multisocketsink still has a reference to the file descriptor when the “client-removed” signal is emitted, so that "get-stats" can be performed on the descriptor; it is therefore not safe to close the file descriptor in the “client-removed” signal handler, and you should use the “client-fd-removed” signal to safely close the fd.

Multisocketsink internally keeps a queue of the incoming buffers and uses a separate thread to send the buffers to the clients. This ensures that no client write can block the pipeline and that clients can read with different speeds.

When adding a client to multisocketsink, the “sync-method” property will define which buffer in the queued buffers will be sent first to the client. Clients can be sent the most recent buffer (which might not be decodable by the client if it is not a keyframe), the next keyframe received in multisocketsink (which can take some time depending on the keyframe rate), or the last received keyframe (which will cause a simple burst-on-connect). Multisocketsink will always keep at least one keyframe in its internal buffers when the sync-mode is set to latest-keyframe.

As of version 0.10.8, there are additional values for the “sync-method” property to allow finer control over burst-on-connect behaviour. By selecting the 'burst' method a minimum burst size can be chosen, 'burst-keyframe' additionally requires that the burst begin with a keyframe, and 'burst-with-keyframe' attempts to burst beginning with a keyframe, but will prefer a minimum burst size even if it requires not starting with a keyframe.

Multisocketsink can be instructed to keep at least a minimum amount of data expressed in time or byte units in its internal queues with the “time-min” and “bytes-min” properties respectively. These properties are useful if the application adds clients with the “add-full” signal to make sure that a burst connect can actually be honored.

When streaming data, clients are allowed to read at a different rate than the rate at which multisocketsink receives data. If the client is reading too fast, no data will be send to the client until multisocketsink receives more data. If the client, however, reads too slowly, data for that client will be queued up in multisocketsink. Two properties control the amount of data (buffers) that is queued in multisocketsink: “buffers-max” and “buffers-soft-max”. A client that falls behind by “buffers-max” is removed from multisocketsink forcibly.

A client with a lag of at least “buffers-soft-max” enters the recovery procedure which is controlled with the “recover-policy” property. A recover policy of NONE will do nothing, RESYNC_LATEST will send the most recently received buffer as the next buffer for the client, RESYNC_SOFT_LIMIT positions the client to the soft limit in the buffer queue and RESYNC_KEYFRAME positions the client at the most recent keyframe in the buffer queue.

multisocketsink will by default synchronize on the clock before serving the buffers to the clients. This behaviour can be disabled by setting the sync property to FALSE. Multisocketsink will by default not do QoS and will never drop late buffers.

Last reviewed on 2006-09-12 (0.10.10)

Synopsis

Element Information

plugin

tcp

author

Thomas Vander Stichele <thomas at apestaart dot org>, Wim Taymans <wim@fluendo.com>, Sebastian Dröge <sebastian.droege@collabora.co.uk>

class

Sink/Network

Element Pads

name

sink

direction

sink

presence

always

details

ANY

Functions

Types and Values

struct GstMultiSocketSink

struct GstMultiSocketSink;

The multisocketsink object structure.


enum GstRecoverPolicy

Possible values for the recovery procedure to use when a client consumes data too slow and has a backlag of more that soft-limit buffers.

Members

GST_RECOVER_POLICY_NONE

   

GST_RECOVER_POLICY_RESYNC_LATEST

   

GST_RECOVER_POLICY_RESYNC_SOFT_LIMIT

   

GST_RECOVER_POLICY_RESYNC_KEYFRAME

   

enum GstSyncMethod

This enum defines the selection of the first buffer that is sent to a new client.

Members

GST_SYNC_METHOD_LATEST

   

GST_SYNC_METHOD_NEXT_KEYFRAME

   

GST_SYNC_METHOD_LATEST_KEYFRAME

   

GST_SYNC_METHOD_BURST

   

GST_SYNC_METHOD_BURST_KEYFRAME

   

GST_SYNC_METHOD_BURST_WITH_KEYFRAME

   

enum GstClientStatus

This specifies the reason why a client was removed from multisocketsink and is received in the "client-removed" signal.

Members

GST_CLIENT_STATUS_OK

   

GST_CLIENT_STATUS_CLOSED

   

GST_CLIENT_STATUS_REMOVED

   

GST_CLIENT_STATUS_SLOW

   

GST_CLIENT_STATUS_ERROR

   

GST_CLIENT_STATUS_DUPLICATE

   

GST_CLIENT_STATUS_FLUSHING

   

Property Details

The “buffers-max” property

  “buffers-max”              gint

max number of buffers to queue for a client (-1 = no limit).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1


The “buffers-min” property

  “buffers-min”              gint

min number of buffers to queue (-1 = as few as possible).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1


The “buffers-queued” property

  “buffers-queued”           guint

Number of buffers currently queued.

Flags: Read

Default value: 0


The “buffers-soft-max” property

  “buffers-soft-max”         gint

Recover client when going over this limit (-1 = no limit).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1


The “burst-format” property

  “burst-format”             GstFormat

The format of the burst units (when sync-method is burst[[-with]-keyframe]).

Flags: Read / Write

Default value: GST_FORMAT_UNDEFINED


The “burst-value” property

  “burst-value”              guint64

The amount of burst expressed in burst-unit.

Flags: Read / Write

Default value: 0


The “bytes-min” property

  “bytes-min”                gint

min number of bytes to queue (-1 = as little as possible).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1


The “bytes-served” property

  “bytes-served”             guint64

Total number of bytes send to all clients.

Flags: Read

Default value: 0


The “bytes-to-serve” property

  “bytes-to-serve”           guint64

Number of bytes received to serve to clients.

Flags: Read

Default value: 0


The “handle-read” property

  “handle-read”              gboolean

Handle client reads and discard the data.

Flags: Read / Write

Default value: TRUE


The “num-sockets” property

  “num-sockets”              guint

The current number of client sockets.

Flags: Read

Default value: 0


The “qos-dscp” property

  “qos-dscp”                 gint

Quality of Service, differentiated services code point (-1 default).

Flags: Read / Write

Allowed values: [G_MAXULONG,63]

Default value: -1


The “recover-policy” property

  “recover-policy”           GstMultiSocketSinkRecoverPolicy

How to recover when client reaches the soft max.

Flags: Read / Write

Default value: Do not try to recover


The “resend-streamheader” property

  “resend-streamheader”      gboolean

Resend the streamheader if it changes in the caps.

Flags: Read / Write

Default value: TRUE


The “sync-method” property

  “sync-method”              GstMultiSocketSinkSyncMethod

How to sync new clients to the stream.

Flags: Read / Write

Default value: Serve starting from the latest buffer


The “time-min” property

  “time-min”                 gint64

min number of time to queue (-1 = as little as possible).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1


The “timeout” property

  “timeout”                  guint64

Maximum inactivity timeout in nanoseconds for a client (0 = no limit).

Flags: Read / Write

Default value: 0


The “unit-type” property

  “unit-type”                GstFormat

The unit to measure the max/soft-max/queued properties.

Flags: Read / Write

Default value: GST_FORMAT_BUFFERS


The “units-max” property

  “units-max”                gint64

max number of units to queue (-1 = no limit).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1


The “units-soft-max” property

  “units-soft-max”           gint64

Recover client when going over this limit (-1 = no limit).

Flags: Read / Write

Allowed values: >= G_MAXULONG

Default value: -1

Signal Details

The “add” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               GSocket            *socket,
               gpointer            user_data)

Hand the given open socket to multisocketsink to write to.

Parameters

gstmultisocketsink

the multisocketsink element to emit this signal on

 

socket

the socket to add to multisocketsink

 

user_data

user data set when the signal handler was connected.

 

Flags: Action


The “add-full” signal

void
user_function (GstMultiSocketSink          *gstmultisocketsink,
               GSocket                     *socket,
               GstMultiHandleSinkSyncMethod sync,
               GstFormat                    format_min,
               guint64                      value_min,
               GstFormat                    format_max,
               guint64                      value_max,
               gpointer                     user_data)

Hand the given open socket to multisocketsink to write to and specify the burst parameters for the new connection.

Parameters

gstmultisocketsink

the multisocketsink element to emit this signal on

 

socket

the socket to add to multisocketsink

 

sync

the sync method to use

 

format_min

the format of value_min

 

value_min

the minimum amount of data to burst expressed in format_min units.

 

format_max

the format of value_max

 

value_max

the maximum amount of data to burst expressed in format_max units.

 

user_data

user data set when the signal handler was connected.

 

Flags: Action


The “clear” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               gpointer            user_data)

Parameters

gstmultisocketsink

the object which received the signal.

 

user_data

user data set when the signal handler was connected.

 

Flags: Action


The “client-added” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               GObject            *socket,
               gpointer            user_data)

The given socket was added to multisocketsink. This signal will be emitted from the streaming thread so application should be prepared for that.

Parameters

gstmultisocketsink

the multisocketsink element that emitted this signal

 

socket

the socket that was added to multisocketsink

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last


The “client-removed” signal

void
user_function (GstMultiSocketSink            *gstmultisocketsink,
               gint                           socket,
               GstMultiHandleSinkClientStatus status,
               gpointer                       user_data)

The given socket is about to be removed from multisocketsink. This signal will be emitted from the streaming thread so applications should be prepared for that.

gstmultisocketsink still holds a handle to socket so it is possible to call the get-stats signal from this callback. For the same reason it is not safe to close() and reuse socket in this callback.

Parameters

gstmultisocketsink

the multisocketsink element that emitted this signal

 

socket

the socket that is to be removed from multisocketsink

 

status

the reason why the client was removed

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last


The “client-socket-removed” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               GSocket            *socket,
               gpointer            user_data)

The given socket was removed from multisocketsink. This signal will be emitted from the streaming thread so applications should be prepared for that.

In this callback, gstmultisocketsink has removed all the information associated with socket and it is therefore not possible to call get-stats with socket . It is however safe to close() and reuse fd in the callback.

Parameters

gstmultisocketsink

the multisocketsink element that emitted this signal

 

socket

the socket that was removed from multisocketsink

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last

Since 0.10.7


The “get-stats” signal

GstStructure*
user_function (GstMultiSocketSink *gstmultisocketsink,
               GSocket            *socket,
               gpointer            user_data)

Get statistics about socket . This function returns a GstStructure.

Parameters

gstmultisocketsink

the multisocketsink element to emit this signal on

 

socket

the socket to get stats of from multisocketsink

 

user_data

user data set when the signal handler was connected.

 

Returns

a GstStructure with the statistics. The structure contains values that represent: total number of bytes sent, time when the client was added, time when the client was disconnected/removed, time the client is/was active, last activity time (in epoch seconds), number of buffers dropped. All times are expressed in nanoseconds (GstClockTime).

Flags: Action


The “remove” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               GSocket            *socket,
               gpointer            user_data)

Remove the given open socket from multisocketsink.

Parameters

gstmultisocketsink

the multisocketsink element to emit this signal on

 

socket

the socket to remove from multisocketsink

 

user_data

user data set when the signal handler was connected.

 

Flags: Action


The “remove-flush” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               GSocket            *socket,
               gpointer            user_data)

Remove the given open socket from multisocketsink after flushing all the pending data to the socket.

Parameters

gstmultisocketsink

the multisocketsink element to emit this signal on

 

socket

the socket to remove from multisocketsink

 

user_data

user data set when the signal handler was connected.

 

Flags: Action


The “client-handle-removed” signal

void
user_function (GstMultiSocketSink *gstmultisocketsink,
               GSocket            *arg1,
               gpointer            user_data)

Parameters

gstmultisocketsink

the object which received the signal.

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last

See Also

tcpserversink