- Generated on Fri Oct 24 2025 14:53:46 by
1.13.2
Generic CoAP message. More...
Generic CoAP message.
The payload of this message can either be represented as a vector (iolist_t) or a buffer. You use unicoap_message_payload_get and unicoap_message_payload_set to work with contiguous payloads. For iolists, refer to unicoap_message_payload_get_chunks, unicoap_message_payload_set_chunks, and unicoap_message_payload_append_chunk.
Regardless of the representation, you can always use unicoap_message_payload_get_size. For vectored payload, this entails an overhead of O(n). If you just want to check whether there is any payload, use unicoap_message_payload_is_empty. You can also make the payload contiguous by calling unicoap_message_payload_make_contiguous, which mutates the message struct. If you purely want to obtain a contiguous representation stored in another buffer, use unicoap_message_payload_copy.
#include <message.h>
Data Fields | ||
| unicoap_options_t * | options | |
| Message options. | ||
| union { | ||
| struct { | ||
| uint8_t * payload | ||
| Message payload. More... | ||
| size_t payload_size | ||
| Size of message payload. More... | ||
| } | ||
| Contiguous payload. | ||
| iolist_t * payload_chunks | ||
| Noncontiguous payload. More... | ||
| }; | ||
| Payload representation. | ||
| union { | ||
| uint8_t code | ||
| CoAP message code. More... | ||
| unicoap_method_t method | ||
| CoAP request method. More... | ||
| unicoap_status_t status | ||
| CoAP response status. More... | ||
| unicoap_signal_t signal | ||
| CoAP signal. More... | ||
| }; | ||
| unicoap_payload_representation_t | payload_representation: 1 | |
| A value indicating how the payload is represented. | ||
CoAP message | |
| static uint8_t * | unicoap_message_payload_get (unicoap_message_t *message) |
| Retrieves contiguous message payload, if available. | |
| static void | unicoap_message_payload_set (unicoap_message_t *message, uint8_t *payload, size_t size) |
| Assigns the given message a contiguous payload. | |
| static iolist_t * | unicoap_message_payload_get_chunks (unicoap_message_t *message) |
| Retrieves noncontiguous message payload, if available. | |
| static void | unicoap_message_payload_set_chunks (unicoap_message_t *message, iolist_t *chunks) |
| Assigns the given message a noncontiguous payload. | |
| static size_t | unicoap_message_payload_get_size (const unicoap_message_t *message) |
| Retrieves payload size, regardless of payload representation. | |
| static uint8_t * | unicoap_message_options_data (const unicoap_message_t *message) |
| Retrieves options storage buffer. | |
| static size_t | unicoap_message_options_size (const unicoap_message_t *message) |
| Retrieves total size of options in buffer. | |
| void | unicoap_message_payload_append_chunk (unicoap_message_t *message, iolist_t *chunk) |
| Appends a payload chunk to a message. | |
| bool | unicoap_message_payload_is_empty (const unicoap_message_t *message) |
| Determines whether message has any payload. | |
| ssize_t | unicoap_message_payload_copy (const unicoap_message_t *message, uint8_t *buffer, size_t capacity) |
| Copies payload into given buffer. | |
| ssize_t | unicoap_message_payload_make_contiguous (unicoap_message_t *message, uint8_t *buffer, size_t capacity) |
| Copies noncontiguous payload into contiguous storage buffer. | |
Message initializers | |
| static void | unicoap_message_init_empty (unicoap_message_t *message, uint8_t code) |
| Initializes message with no payload and no options. | |
| static void | unicoap_message_init (unicoap_message_t *message, uint8_t code, uint8_t *payload, size_t payload_size) |
| Initializes message with payload but no options. | |
| static void | unicoap_message_init_string (unicoap_message_t *message, uint8_t code, const char *payload) |
| Initializes message with payload from null-terminated UTF-8 string but no options. | |
| static void | unicoap_message_init_with_options (unicoap_message_t *message, uint8_t code, uint8_t *payload, size_t payload_size, unicoap_options_t *options) |
| Initializes message with byte payload and options. | |
| static void | unicoap_message_init_string_with_options (unicoap_message_t *message, uint8_t code, const char *payload, unicoap_options_t *options) |
| Initializes message with payload from null-terminated UTF-8 string and options. | |
Signaling messages | |
| static unicoap_signal_t | unicoap_message_get_signal (const unicoap_message_t *message) |
| Retrieves signal code from given signal message. | |
| static void | unicoap_message_set_signal (unicoap_message_t *message, unicoap_signal_t signal) |
| Sets signal code of given signal message. | |
Request messages | |
| static unicoap_method_t | unicoap_request_get_method (const unicoap_message_t *request) |
| Obtains request method from the given message's code. | |
| static void | unicoap_request_set_method (unicoap_message_t *request, unicoap_method_t method) |
| Sets request method. | |
| static void | unicoap_request_init_empty (unicoap_message_t *request, unicoap_method_t method) |
| Initializes request with no payload and no options. | |
| static void | unicoap_request_init (unicoap_message_t *request, unicoap_method_t method, uint8_t *payload, size_t payload_size) |
| Initializes request with payload but no options. | |
| static void | unicoap_request_init_string (unicoap_message_t *request, unicoap_method_t method, const char *payload) |
| Initializes request with payload from null-terminated UTF-8 string but no options. | |
| static void | unicoap_request_init_with_options (unicoap_message_t *request, unicoap_method_t method, uint8_t *payload, size_t payload_size, unicoap_options_t *options) |
| Initializes request with byte payload and options. | |
| static void | unicoap_request_init_string_with_options (unicoap_message_t *request, unicoap_method_t method, const char *payload, unicoap_options_t *options) |
| Initializes request with payload from null-terminated UTF-8 string and options. | |
Response messages | |
| static unicoap_status_t | unicoap_response_get_status (const unicoap_message_t *response) |
| Obtains response status from the given message's code. | |
| static void | unicoap_response_set_status (unicoap_message_t *response, unicoap_status_t status) |
| Sets response status. | |
| static void | unicoap_response_init_empty (unicoap_message_t *response, unicoap_status_t status) |
| Initializes response with no payload and no options. | |
| static void | unicoap_response_init (unicoap_message_t *response, unicoap_status_t status, uint8_t *payload, size_t payload_size) |
| Initializes response with payload but no options. | |
| static void | unicoap_response_init_string (unicoap_message_t *response, unicoap_status_t status, const char *payload) |
| Initializes response with payload from null-terminated UTF-8 string but no options. | |
| static void | unicoap_response_init_with_options (unicoap_message_t *response, unicoap_status_t status, uint8_t *payload, size_t payload_size, unicoap_options_t *options) |
| Initializes response with byte payload and options. | |
| static void | unicoap_response_init_string_with_options (unicoap_message_t *response, unicoap_status_t status, const char *payload, unicoap_options_t *options) |
| Initializes response with payload from null-terminated UTF-8 string and options. | |
| uint8_t unicoap_message_t::code |
CoAP message code.
A message code is divided into the class bits and detail bits, where C is a class bit and D is a detail bit. The class bits form a single-digit number, the detail bits represents a two-digit number. Hence, message codes are written as c.dd where c is the unsigned integer encoded in the three C bits and dd is the beforementioned two-digit number encoded in the five D bits.
| unicoap_method_t unicoap_message_t::method |
CoAP request method.
| unicoap_options_t* unicoap_message_t::options |
| uint8_t* unicoap_message_t::payload |
Message payload.
Access via unicoap_message_payload_get and unicoap_message_payload_set.
| iolist_t* unicoap_message_t::payload_chunks |
Noncontiguous payload.
Use one of these APIs:
| unicoap_payload_representation_t unicoap_message_t::payload_representation |
A value indicating how the payload is represented.
If the payload is noncontiguous, the unicoap_message_t::payload_chunks property must be accessed. Otherwise, only unicoap_message_t::payload must be read and written to.
| size_t unicoap_message_t::payload_size |
Size of message payload.
Number of bytes in unicoap_message_t::payload. Access via unicoap_message_payload_get_size.
| unicoap_signal_t unicoap_message_t::signal |
CoAP signal.
Check if this is a signaling message before reading this property using unicoap_message_is_signal.
| unicoap_status_t unicoap_message_t::status |
CoAP response status.
1.13.2