SiWx91x Sockets#

sl_si91x_socket_receive_data_callback_t#

sl_si91x_socket_receive_data_callback_t )(uint32_t socket, uint8_t *buffer, uint32_t length, const sl_si91x_socket_metadata_t *firmware_socket_response)

Callback function reads asynchronous data from the socket.

The callback function reads asynchronous data from the socket when the sl_si91x_socket_async API is registered and called. The callback provides the following details: socket ID, pointer to the buffer which contains receiver data, size of the buffer, and metadata of the receiver packet (such as IP address, and port number).

Returns

• N/A

sl_si91x_socket_accept_callback_t#

sl_si91x_socket_accept_callback_t )(int32_t socket, struct sockaddr *addr, uint8_t ip_version)

Callback functions for new asynchronous accepted connection.

The callback provides paramenters for new accepted connection when the sl_si91x_accept_async API is registered and called. The callback provides the following details: socket ID of the accepted connection, address of remoter peer, and IP version of connection.

Returns

• N/A

sl_si91x_socket_data_transfer_complete_handler_t#

sl_si91x_socket_data_transfer_complete_handler_t )(int32_t socket, uint16_t length)

Callback function indicates data transfer status.

The callback indicates the data transfer completion status when either of the sl_si91x_send_async or sl_si91x_sendto_async API is registered and called. The callback provides the socket ID, and the number of bytes that are successfully transfer.

Returns

• N/A

sl_si91x_socket_select_callback_t#

sl_si91x_socket_select_callback_t )(fd_set *fd_read, fd_set *fd_write, fd_set *fd_except, int32_t status)

Callback function indicates asynchronous select request result.

The callback indicates asynchronous response reaches the select request when the sl_si91x_select API is registered and called. The callback provides the following details: file descriptor sets for read, write, and exception conditions, and status of the selected request.

Returns

• N/A

sl_si91x_socket_remote_termination_callback_t#

sl_si91x_socket_remote_termination_callback_t )(int socket, uint16_t port, uint32_t bytes_sent)

Callback function indicates termination of the remote socket.

The callback function notifies on the termination of the remote socket when the sl_si91x_set_remote_termination_callback API is registered and called. The callback provides the following details: socket ID, remote socket port number, and number of bytes sent before termination of the remote socket.

Returns

• The callback does not returns value.

sl_si91x_socket#

int sl_si91x_socket (int family, int type, int protocol)

Creates a new socket.

The function creates a new socket and returns a file descriptor for the respective socket. The socket is used for communication within the specified protocol family, type, and protocol. The created socket is used for various network operations such as, connecting to a remote host, sending and receiving data, and so on.

Returns

• Returns the socket ID or file descriptor for the newly created socket on success, or -1 on failure.

sl_si91x_socket_async#

int sl_si91x_socket_async (int family, int type, int protocol, sl_si91x_socket_receive_data_callback_t callback)

Creates an asynchronous socket and registers the provided callback.

This function creates a new asynchronous socket and registers a callback function that is called whenever data is received on the socket. The socket can be used for communication within the specified protocol family, type, and protocol.

Returns

• Returns the socket ID or file descriptor for the newly created socket on success, or -1 on failure.

sl_si91x_setsockopt#

int sl_si91x_setsockopt (int32_t socket, int level, int option_name, const void * option_value, socklen_t option_len)

Sets a specified socket option on the identified socket asynchronously.

This function sets a specified option for a given socket asynchronously. The options can be set at various levels and include parameters such as receive timeout, maximum retries, maximum segment size, TCP keepalive, SSL options, and so on.

Returns

• Returns 0 on success, or -1 on failure.

Note

• This function is used only for the SiWx91x socket API. The options set in this function will not be effective if called after sl_si91x_connect() or sl_si91x_listen() for TCP, or after sl_si91x_sendto(), sl_si91x_recvfrom(), or sl_si91x_connect() for UDP. The value of the option SL_SI91X_SO_MAX_RETRANSMISSION_TIMEOUT_VALUE should be a power of 2.

sl_si91x_bind#

int sl_si91x_bind (int socket, const struct sockaddr * addr, socklen_t addr_len)

Assigns a local protocol address to a socket.

The function binds a socket to a specific local address and port number. It is typically used on the server side to specify the port on which the server will listen for incoming connections.

Returns

• Returns 0 on success, or -1 on failure.

sl_si91x_listen#

int sl_si91x_listen (int socket, int max_number_of_clients)

Enables a socket to listen for remote connection requests in passive mode.

The function configures a socket to listen for incoming connection requests. It is typically used on the server side after the socket has been bound to a local address using the sl_si91x_bind function. The socket enters passive mode, where it waits for remote clients to connect.

Returns

• Returns 0 on success, or -1 on failure.

sl_si91x_accept#

int sl_si91x_accept (int socket, const struct sockaddr * addr, socklen_t addr_len)

Accepts a connection request from a remote peer.

The function blocks until a client attempts to connect to the server socket. After receiving a connection request, it proceeds.

Returns

• int

sl_si91x_accept_async#

int sl_si91x_accept_async (int socket, sl_si91x_socket_accept_callback_t callback)

Accepts a connection request from the remote peer and registers a callback.

The function sets up the server socket to listen for incoming connections, and immediately returns without blocking the main program's execution.

Returns

• int

sl_si91x_connect#

int sl_si91x_connect (int socket, const struct sockaddr * addr, socklen_t addr_len)

Initiates a connection to a remote socket specified by the addr parameter.

The function initiates a connection to a remote socket specified by the addr parameter. It is typically used on the client side to establish a connection to a server.

Returns

• int

sl_si91x_send#

int sl_si91x_send (int socket, const uint8_t * buffer, size_t buffer_length, int32_t flags)

Sends the data to the remote peer on the given socket.

This should be used only when the socket is in a connected state.

Returns

• int

Note

• The flags parameter is not currently supported.

• For TCP, the maximum buffer length should not exceed the MSS.

• The following table lists the maximum buffer length which could be sent over each supported protocol.

sl_si91x_send_async#

int sl_si91x_send_async (int socket, const uint8_t * buffer, size_t buffer_length, int32_t flags, sl_si91x_socket_data_transfer_complete_handler_t callback)

Transmits one or more messages to a socket asynchronously.

This should be used only when the socket is in a connected state.

Returns

• int

Note

• The flags parameter is not currently supported.

• For TCP, the maximum buffer length should not exceed the MSS.

• The following table lists the maximum buffer length which could be sent over each supported protocol.

sl_si91x_sendto#

int sl_si91x_sendto (int socket, const uint8_t * buffer, size_t buffer_length, int32_t flags, const struct sockaddr * addr, socklen_t addr_len)

Transmits one or more messages to another socket.

The function is called from an unconnected socket, typically like a UDP socket.

Returns

• int

Note

• The flags parameter is not currently supported.

• For TCP, the maximum buffer length should not exceed the MSS.

• The following table lists the maximum buffer length which could be sent over each supported protocol.

sl_si91x_sendto_async#

int sl_si91x_sendto_async (int socket, const uint8_t * buffer, size_t buffer_length, int32_t flags, const struct sockaddr * to_addr, socklen_t to_addr_len, sl_si91x_socket_data_transfer_complete_handler_t callback)

Transmits one or more messages to another socket asynchronously, and receives acknowledgement through the registered callback.

The function can also be called from an unconnected socket, typically like a UDP socket.

Returns

• int

Note

• The flags parameter is not currently supported.

• For TCP, the maximum buffer length should not exceed the MSS.

• The following table lists the maximum buffer length which could be sent over each supported protocol.

sl_si91x_send_large_data#

int sl_si91x_send_large_data (int socket, const uint8_t * buffer, size_t buffer_length, int32_t flags)

Sends data that is larger than the Maximum Segment Size (MSS).

This function sends data that exceeds the MSS size to a remote peer. It handles the segmentation of the data into smaller chunks that fit within the MSS limit. This API can even be used when the buffer length is less than the MSS.

Returns

• Returns the number of bytes sent on success, or -1 on failure.

sl_si91x_recv#

int sl_si91x_recv (int socket, uint8_t * buffer, size_t bufferLength, int32_t flags)

Receives data from a connected socket.

This function receives data from a connected socket and stores it in the specified buffer. It is typically used on the client or server side to read incoming data from a remote peer.

Returns

• Returns the number of bytes received on success, or -1 on failure.

sl_si91x_recvfrom#

int sl_si91x_recvfrom (int socket, uint8_t * buffer, size_t buffersize, int32_t flags, struct sockaddr * fromAddr, socklen_t * fromAddrLen)

Receives data from an unconnected socket, typically a UDP socket.

This function receives data from an unconnected socket and stores it in the specified buffer. It is typically used to receive data from a remote peer without establishing a connection.

Returns

• Returns the number of bytes received on success, or -1 on failure.

sl_si91x_shutdown#

int sl_si91x_shutdown (int socket, int how)

Disables send or receive operations on a socket.

This function disables further send or receive operations on a specified socket. It can either close a specific socket or all sockets associated with a given port number.

Returns

• Returns 0 on success, or -1 on failure.

Note

• If the socket is a server socket, the how parameter is ignored, and the socket is always closed based on the port number.

sl_si91x_select#

int sl_si91x_select (int nfds, fd_set * readfds, fd_set * writefds, fd_set * exceptfds, const struct timeval * timeout, sl_si91x_socket_select_callback_t callback)

The sl_si91x_select() function is used to monitor multiple file descriptors for readiness to perform I/O operations.

The file descriptors in the sets are monitored to see if they are ready for reading, ready for writing, or have an error condition pending.

sl_si91x_select() allows a program to monitor multiple file descriptors, waiting until one or more of the file descriptors become "ready" for some class of I/O operation (e.g., input possible). A file descriptor is considered ready if it is possible to perform a corresponding I/O operation without blocking.

Returns

• If callback is provided, the function will immediately return zero for success, and -1 for failure. If callback is NULL, returns:

  • total number of file descriptors set on success.

  • 0 when no file descriptors are ready within the specified timeout.

  • -1 on failure.

Note

• The select function modifies the sets passed to it, so if the function is to be called again, the sets must be reinitialized. The exceptfds parameter is not currently supported.

sl_si91x_set_remote_termination_callback#

void sl_si91x_set_remote_termination_callback (sl_si91x_socket_remote_termination_callback_t callback)

Registers a callback for remote socket termination events.

This function registers a callback function is called when a remote socket is terminated. The callback function should be of type sl_si91x_socket_remote_termination_callback_t.

sl_si91x_get_socket_info#

sl_status_t sl_si91x_get_socket_info (sl_si91x_socket_info_response_t * socket_info_response)

Retrieve information about currently opened sockets from the network stack.

Returns

• sl_status_t

Note

• The socket IDs in the response are specific to the firmware and should not be used as file descriptors in socket APIs.

sl_si91x_get_socket_mss#

int16_t sl_si91x_get_socket_mss (int32_t socketIndex)

Retrieves the Maximum Segment Size (MSS) for a specific socket.

The MSS is the largest amount of data, specified in bytes, that a computer or communications device can handle in a single, unfragmented piece. Returns

• Returns an int16_t value representing the MSS of the specified socket in bytes.