UDP¶

Types¶

Name	Type	Description
`mira_net_udp_connection_t`	`struct`
`mira_net_udp_callback_t`	`void()(mira_net_udp_connection_t connection, const void data, uint16_t data_len, const mira_net_udp_callback_metadata_t metadata, void *storage)`

Structs¶

mira_net_udp_callback_metadata_t¶

Type	Name	Description
`mira_net_address_t`	source_address
`mira_net_address_t`	destination_address
`uint16_t`	source_port
`uint16_t`	destination_port

Functions¶

mira_net_udp_listen¶

mira_net_udp_connection_t* mira_net_udp_listen(
    uint16_t                 port,
    mira_net_udp_callback_t  callback,
    void*                    storage);

Listen the specified UDP port.

Note: Can not be called before mira_net_init.

Parameters

Parameter	Description
`port`	The port number, zero means the system will allocate it.
`callback`	Callback function with data.
`storage`	Storage pointer which is used to store optional information to be used by the callback function. E.g. it could be used as an identifier or to pass on a configuration struct.

Return

A UDP connection on the specified port or NULL if it fails.

mira_net_udp_listen_address¶

mira_net_udp_connection_t* mira_net_udp_listen_address(
    const mira_net_address_t*  address,
    uint16_t                   port,
    mira_net_udp_callback_t    callback,
    void*                      storage);

Listen to the specified UDP port and address.

Please see mira_net_udp_multicast_group_join() for more info about handling multicast groups.

Note: Can not be called before mira_net_init. No verification is made of the address.

Parameters

Parameter	Description
`address`	The link-local multicast IP address to listen to, NULL means all IP addresses.
`port`	The port number, zero means the system will allocate it.
`callback`	Callback function with data.
`storage`	Storage pointer which is used to store optional information to be used by the callback function. E.g. it could be used as an identifier or to pass on a configuration struct.

Return

A UDP connection on the specified port or NULL if it fails.

mira_net_udp_connect¶

mira_net_udp_connection_t* mira_net_udp_connect(
    const mira_net_address_t*  address,
    uint16_t                   port,
    mira_net_udp_callback_t    callback,
    void*                      storage);

Connect via UDP to the specified IP address and port.

When address is NULL, the socket will not bind to a specific remote address and mira_net_udp_send_to has to be used to send messages.

Note: Can not be called before mira_net_init.

Parameters

Parameter	Description
`address`	The IP address to connect to.
`port`	The remote port number to connect to. Discarded if address is NULL.
`callback`	UDP callback function.
`storage`	Storage pointer that is used to store optional information to be used by the callback function. E.g. it could be used as an identifier or to pass on a configuration struct.

Return

The UDP Connection or NULL if it fails.

mira_net_udp_bind¶

mira_net_udp_connection_t* mira_net_udp_bind(
    const mira_net_address_t*  remote_address,
    uint16_t                   remote_port,
    uint16_t                   local_port,
    mira_net_udp_callback_t    callback,
    void*                      storage);

Bind a socket and sets up a connection.

When remote_address is NULL, the socket does not have a remote address and mira_net_udp_send_to has to be used when sending messages.

If local_port is 0, a random number within the 49152 to 65535 range will be used.

Note: Can not be called before mira_net_init.

Parameters

Parameter	Description
`remote_address`	IP address to bind to.
`remote_port`	The remote port to connect to. Discarded if address is NULL.
`local_port`	The local port to bind the connection to.
`callback`	UDP callback function.
`storage`	Storage pointer which is used to store optional information to be used by the callback function. E.g. it could be used as an identifier or to pass on a configuration struct.

Return

The UDP Connection or NULL if it fails.

mira_net_udp_bind_address¶

mira_net_udp_connection_t* mira_net_udp_bind_address(
    const mira_net_address_t*  remote_address,
    const mira_net_address_t*  local_address,
    uint16_t                   remote_port,
    uint16_t                   local_port,
    mira_net_udp_callback_t    callback,
    void*                      storage);

Binds a socket to a local address and/or sets up a connection.

When remote_address is NULL, the socket does not have a remote address and mira_net_udp_send_to has to be used when sending messages.

When local_address is NULL, the socket listens to all available addresses. Please see mira_net_udp_multicast_group_join() for more info about multicast groups.

If local_port is 0, a random number within the 49152 to 65535 range will be used.

Note: Can not be called before mira_net_init. No verification is made of local_address.

Parameters

Parameter	Description
`remote_address`	IP address to bind to.
`local_address`	IP link-local multicast IP address to listen to.
`remote_port`	The remote port to connect to.
`local_port`	The local port to bind the connection to.
`callback`	UDP callback function.
`storage`	Storage pointer which is used to store optional information to be used by the callback function. E.g. it could be used as an identifier or to pass on a configuration struct.

Return

The UDP Connection or NULL if it fails.

mira_net_udp_close¶

mira_status_t mira_net_udp_close(
    mira_net_udp_connection_t*  mira_udp_connection);

Close the specified connection.

Parameters

Parameter	Description
`mira_udp_connection`	The UDP connection to close.

Return

MIRA_SUCCESS if successful.

MIRA_NET_ERROR_INVALID_SOCKET if socket is not free.

MIRA_ERROR_INVALID_VALUE if wrong input parameter.

mira_net_udp_multicast_group_join¶

mira_status_t mira_net_udp_multicast_group_join(
    mira_net_udp_connection_t*  mira_udp_connection,
    const mira_net_address_t*   multicast_address);

Join a multicast group.

Add a socket to a multicast group.

To be able to receive packets to a multicast address, the address must be joined (with this call) and the socket must also listen to all addresses or to the multicast address (using mira_net_udp_listen_address or mira_net_udp_bind_address).

The node leaves the group when all sockets have left the group. Sockets leave the group when mira_net_udp_multicast_group_leave() is called and when they are closed.

To control latency and current consumption, the address needs to follow a certain the format: ff02::3fRR:XXXX, where RR is the rate, from 0-31, same as for mira_net_init(). XXXX is an any number.

Lower value of rate decreases latency and increases throughput, to the cost of current consumption.

Only one multicast group is allowed per socket.

Note: The address must be a link-local multicast address to bind to, no verification is done of it.

Parameters

Parameter	Description
`mira_udp_connection`	The UDP connection to use for multicast address.
`multicast_address`	The address of the multicast group to join.

Return

MIRA_SUCCESS If successful.

MIRA_ERROR_INVALID_VALUE Invalid argument.

MIRA_ERROR_NO_MEMORY No space for additional multicast addresses in socket.

mira_net_udp_multicast_group_leave¶

mira_status_t mira_net_udp_multicast_group_leave(
    mira_net_udp_connection_t*  mira_udp_connection,
    const mira_net_address_t*   multicast_address);

Leave a multicast group.

Leave a group that previously was joined using mira_net_udp_multicast_group_join. Sockets will also leave the group when they are closed.

Parameters

Parameter	Description
`mira_udp_connection`	The UDP connection to close.
`multicast_address`	The address of the multicast group to leave.

Return

MIRA_SUCCESS If successful.

MIRA_NET_ERROR_NO_ADDRESS_SET Socket is not bound to address.

MIRA_ERROR_INVALID_VALUE Invalid argument.

mira_net_udp_send¶

mira_status_t mira_net_udp_send(
    mira_net_udp_connection_t*  mira_udp_connection,
    const void*                 data,
    uint16_t                    data_len);

Sends a data string over a specified UDP connection.

The connection must be created with a remote address and port to use this method. To specify the remote address and port when sending, use the mira_net_udp_send_to() method.

Note: When sending to link-local multicast addresses, expect lower delivery rates due to lack of retransmissions. Also when packet is fragmented, the delivery rates will reduced further. Recommend maximum packet size to avoid fragmentation is 160 bytes.

Parameters

Parameter	Description
`mira_udp_connection`	The UDP connection to use for the transmission.
`data`	The data to be sent.
`data_len`	The length, in bytes, of the data to be sent. At most 800 should be used.

Return

See enum definition.

Value	Description
`MIRA_SUCCESS`	UDP packet successfully sent.
`MIRA_NET_ERROR_SEND_FAILED`	Sending UDP packet failed.

mira_net_udp_send_to¶

mira_status_t mira_net_udp_send_to(
    mira_net_udp_connection_t*  mira_udp_connection,
    const mira_net_address_t*   address,
    uint16_t                    port,
    const void*                 data,
    uint16_t                    data_len);

Sends a data string via UDP to a specified IP address.

To reply to a received message, use mira_net_udp_send_to() with addess and port set to the values from metadata->source_address and metadata->source_port from the receive callback.

Note: When sending to link-local multicast addresses, expect lower delivery rates due to lack of retransmissions. Also when packet is fragmented, the delivery rates will reduced further. Recommend maximum packet size to avoid fragmentation is 160 bytes.

Parameters

Parameter	Description
`mira_udp_connection`	The UDP connection to use for the transmission.
`address`	The IP address to send to, i.e. the receiver.
`port`	The UDP port to send to.
`data`	Data to send as vector.
`data_len`	The length of the data vector to send. At most 800 should be used.

Return

See enum definition.

Value	Description
`MIRA_SUCCESS`	UDP packet successfully sent.
`MIRA_NET_ERROR_SEND_FAILED`	Sending UDP packet failed.