CoAP#

The Wi-SUN CoAP component provides an application layer implementation on top of the Wi-SUN stack and its socket API. The CoAP protocol is designed as a specialized Internet Application Protocol for constrained devices in lossy networks (see RFC 7252 for additional information). Wi-SUN FAN networks fit this definition. The CoAP implementation relies on the UDP transport layer to send and receive packets.

A number of helper functions are part of the component to help build CoAP payloads, parse CoAP packets, free CoAP packets, and more.

The CoAP Resource Handler service handles registered resources. Resource Discovery request provides an interface to get information about available resources. Resource has more attributes over URI (Uniform Resource Identifier) path, which can be filtered by particular Resource Discovery request.

The CoAP Notification service provides an interface to create and schedule notifications to the remote host. Schedule time and send condition can be customized depending on the application.

To use the CoAP component in your application, add it to your project and initialize it with sl_wisun_coap_init().

The Wi-SUN CoAP component offers an application layer implementation built on top of the Wi-SUN stack and its socket API. The CoAP protocol is specifically designed as an Internet Application Protocol for constrained devices operating in lossy networks (as defined in RFC 7252). Wi-SUN FAN networks precisely fit this definition.

The CoAP implementation relies on the UDP transport layer for sending and receiving packets. Within the component, you'll find a set of helper functions that assist in building CoAP payloads, parsing CoAP packets, and freeing CoAP packets. Additionally, the CoAP Resource Handler service manages registered resources.

For resource discovery, the Resource Discovery request provides an interface to retrieve information about available resources. These resources have additional attributes beyond the URI (Uniform Resource Identifier) path, which can be selectively filtered using specific Resource Discovery requests.

Furthermore, the CoAP Notification service allows you to create and schedule notifications for the remote host. You can customize the schedule time and send conditions based on your application requirements. To incorporate the CoAP component into your application, simply add it to your project and initialize it using sl_wisun_coap_init().

Modules#

CoAP type definitions

Functions#

sl_wisun_coap_build_response(const sl_wisun_coap_packet_t *req, sl_wisun_coap_message_code_t msg_code)

Build generic response for request wrapper function.

int16_t
sl_wisun_coap_builder(uint8_t *dest_buff, const sl_wisun_coap_packet_t *message)

CoAP message builder Wi-SUN.

uint16_t
sl_wisun_coap_builder_calc_size(const sl_wisun_coap_packet_t *message)

CoAP packet calc size wrapper.

void
sl_wisun_coap_destroy_packet(sl_wisun_coap_packet_t *packet)

Destroy packet.

__STATIC_INLINE void

Destroy payload string.

__STATIC_INLINE void

Destroy URI path string.

void
sl_wisun_coap_free(void *addr)

Free Wi-SUN CoAP.

Get the library handler pointer from the internal handler structure.

char *
sl_wisun_coap_get_payload_str(const sl_wisun_coap_packet_t *const packet)

Prepare payload string.

char *
sl_wisun_coap_get_uri_path_str(const sl_wisun_coap_packet_t *const packet)

Prepare URI path string.

void
sl_wisun_coap_init(const sl_wisun_coap_tx_callback tx_callback, const sl_wisun_coap_rx_callback rx_callback, const sl_wisun_coap_version_t version)

Initialize Wi-SUN CoAP.

__STATIC_INLINE void

Initialize Wi-SUN CoAP default.

void *
sl_wisun_coap_malloc(uint16_t size)

Implement malloc.

sl_wisun_coap_parser(uint16_t packet_data_len, uint8_t *packet_data)

CoAP parser wrapper function.

void
sl_wisun_coap_print_packet(const sl_wisun_coap_packet_t *packet, const bool hex_format)

Print CoAP packets and all of attached buffer, payload, token, uri_path.

Macros#

#define

CoAP Service loop.

Function Documentation#

sl_wisun_coap_build_response#

sl_wisun_coap_packet_t * sl_wisun_coap_build_response (const sl_wisun_coap_packet_t *req, sl_wisun_coap_message_code_t msg_code)

Build generic response for request wrapper function.

Parameters
[in]req

request

[in]msg_code

message code to build

Used sn_coap_build_response. Returns

  • sl_wisun_coap_header_t* built packet ptr on the heap


Definition at line 237 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_builder#

int16_t sl_wisun_coap_builder (uint8_t *dest_buff, const sl_wisun_coap_packet_t *message)

CoAP message builder Wi-SUN.

Parameters
[out]dest_buff

destination buffer for raw message

[in]message

message structure

Used sl_wisun_coap_builder. Returns

  • int16_t On success bytes of built message, on failure -1 if CoAP header structure is wrong -2 if NULL ptr set as argument


Definition at line 227 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_builder_calc_size#

uint16_t sl_wisun_coap_builder_calc_size (const sl_wisun_coap_packet_t *message)

CoAP packet calc size wrapper.

Parameters
[in]message

message ptr

Used sn_coap_builder_calc_needed_packet_data_size. Returns

  • uint16_t size


Definition at line 216 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_destroy_packet#

void sl_wisun_coap_destroy_packet (sl_wisun_coap_packet_t *packet)

Destroy packet.

Parameters
N/Apacket

packet

It must be used to avoid memory leaks! Free the all of allocated buffer for packet


Definition at line 280 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_destroy_payload_str#

__STATIC_INLINE void sl_wisun_coap_destroy_payload_str (char *str)

Destroy payload string.

Parameters
[in]str

String

'\0' terminated string in the heap, it must be freed


Definition at line 295 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_destroy_uri_path_str#

__STATIC_INLINE void sl_wisun_coap_destroy_uri_path_str (char *uri_str)

Destroy URI path string.

Parameters
[in]uri_str

URI string ptr

Call free on allocated pointer


Definition at line 262 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_free#

void sl_wisun_coap_free (void *addr)

Free Wi-SUN CoAP.

Parameters
N/Aaddr

address ptr

OS-dependent thread-safe implementation.


Definition at line 198 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_get_lib_handler#

const sl_wisun_coap_handle_t * sl_wisun_coap_get_lib_handler (void)

Get the library handler pointer from the internal handler structure.

Parameters
N/A

Not thread safe! It is needed only to use Pelion mbed-coap library functions Returns

  • const sl_wisun_coap_handle_t* pointer to the lib handler


Definition at line 272 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_get_payload_str#

char * sl_wisun_coap_get_payload_str (const sl_wisun_coap_packet_t *const packet)

Prepare payload string.

Parameters
[in]packet

Packet

'\0' terminated string in the heap, it must be freed Returns

  • char* payload string, NULL on error


Definition at line 288 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_get_uri_path_str#

char * sl_wisun_coap_get_uri_path_str (const sl_wisun_coap_packet_t *const packet)

Prepare URI path string.

Parameters
[in]packet

Packet

'\0' terminated string in the heap, it must be freed Returns

  • char* URI path string, NULL on error


Definition at line 255 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_init#

void sl_wisun_coap_init (const sl_wisun_coap_tx_callback tx_callback, const sl_wisun_coap_rx_callback rx_callback, const sl_wisun_coap_version_t version)

Initialize Wi-SUN CoAP.

Parameters
[in]tx_callback

TX callback, if it's NULL, the default callback is applied

[in]rx_callback

RX callback, if it's NULL, the default callback is applied

[in]version

CoAP version

Set the Wi-SUN CoAP internal descriptor.


Definition at line 172 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_init_default#

__STATIC_INLINE void sl_wisun_coap_init_default (void)

Initialize Wi-SUN CoAP default.

Parameters
N/A

Initializes the internal descriptor with default values.


Definition at line 180 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_malloc#

void * sl_wisun_coap_malloc (uint16_t size)

Implement malloc.

Parameters
N/Asize

size for malloc

OS-dependent thread-safe implementation. Returns

  • void* the memory pointer


Definition at line 191 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_parser#

sl_wisun_coap_packet_t * sl_wisun_coap_parser (uint16_t packet_data_len, uint8_t *packet_data)

CoAP parser wrapper function.

Parameters
[in]packet_data_len

packet data size

[in]packet_data

packet data ptr

Used sn_coap_parser Returns

  • sl_wisun_coap_packet_t* Parsed packet pointer


Definition at line 207 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

sl_wisun_coap_print_packet#

void sl_wisun_coap_print_packet (const sl_wisun_coap_packet_t *packet, const bool hex_format)

Print CoAP packets and all of attached buffer, payload, token, uri_path.

Parameters
[in]packet

packet to print

[in]hex_format

hex format bool to decide buffer print format

Pretty printer function, with hex format option for buffers


Definition at line 246 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h

Macro Definition Documentation#

SL_COAP_SERVICE_LOOP#

#define SL_COAP_SERVICE_LOOP
Value:
()

CoAP Service loop.


Definition at line 64 of file /mnt/raid/workspaces/ws.TauBzA8CM/overlay/gsdk/app/wisun/component/coap/sl_wisun_coap.h