An implementation of CoAP

Topics
	CoAP keystore API
	CoAP timer API
	CoAP transport API

Files
file	coap-request-state.h
	Common request state for all the APIs.

Macros
#define	COAP_MAX_PACKET_SIZE   (COAP_MAX_HEADER_SIZE + COAP_MAX_CHUNK_SIZE)
	The max size of the CoAP messages.

Enumerations
enum	coap_resource_flags_t
	Resource flags for allowed methods and special functionalities.

Functions
int	coap_block1_handler (coap_message_t *request, coap_message_t *response, uint8_t *target, size_t *len, size_t max_len)
	Block 1 support within a CoAP resource.
int	coap_send_request (coap_callback_request_state_t *callback_state, coap_endpoint_t *endpoint, coap_message_t *request, void(*callback)(coap_callback_request_state_t *callback_state))
	Send a CoAP request to a remote endpoint.
void	coap_activate_resource (coap_resource_t *resource, const char *path)
	Makes a resource available under the given URI path.
coap_resource_t *	coap_get_first_resource (void)
	Returns the first of the registered CoAP resources.
coap_resource_t *	coap_get_next_resource (coap_resource_t *resource)
	Returns the next registered CoAP resource.
void	coap_log_string (const char *text, size_t len)
	Logs a CoAP string that has a length specified, but might not be zero-terminated.
void	coap_separate_reject ()
	Reject a request that would require a separate response with an error message.
void	coap_separate_accept (coap_message_t *coap_req, coap_separate_t *separate_store)
	Initiate a separate response with an empty ACK.

Detailed Description

This is an implementation of the Constrained Application Protocol

Function Documentation

coap_activate_resource()

void coap_activate_resource	(	coap_resource_t *	resource,
		const char *	path )

Makes a resource available under the given URI path.

Resources wanted to be accessible should be activated with the following code.

The resource implementation must be imported first using the extern keyword. The build system takes care of compiling every *.c file in the ./resources/ sub-directory (see example Makefile).

Parameters

resource	A CoAP resource defined through the RESOURCE macros.
path	The local URI path where to provide the resource.

Definition at line 397 of file coap-engine.c.

References coap_timer_set(), coap_timer_set_callback(), coap_timer_set_user_data(), and list_add().

coap_block1_handler()

int coap_block1_handler	(	coap_message_t *	request,
		coap_message_t *	response,
		uint8_t *	target,
		size_t *	len,
		size_t	max_len )

Block 1 support within a CoAP resource.

   This function will help you to use block 1. If the target
   parameter is \p NULL, then error handling and response
   configuration is active.

   You can find an example in
   examples/coap/coap-example-server/resources/res-b1-sep-b2.c

Parameters

request	Request pointer from the handler.
response	Response pointer from the handler.
target	Pointer to the buffer where the request payload can be assembled.
len	Pointer to the variable where the function stores the actual length.
max_len	Length of the target buffer.

Returns

0 if the initialisation was successful, 1 if more blocks will follow, or -1 if the initialisation failed.

Definition at line 84 of file coap-block1.c.

coap_get_first_resource()

coap_resource_t * coap_get_first_resource

(

void

)

Returns the first of the registered CoAP resources.

Returns

The first registered CoAP resource or NULL if none exists.

Definition at line 422 of file coap-engine.c.

References list_head().

coap_get_next_resource()

coap_resource_t * coap_get_next_resource

(

coap_resource_t *

resource

)

Returns the next registered CoAP resource.

Returns

The next resource or NULL if no more exists.

Definition at line 428 of file coap-engine.c.

References list_item_next().

coap_log_string()

void coap_log_string	(	const char *	text,
		size_t	len )

Logs a CoAP string that has a length specified, but might not be zero-terminated.

Parameters

text	The CoAP string.
len	The number of characters in the CoAP string.

Definition at line 47 of file coap-log.c.

coap_send_request()

int coap_send_request	(	coap_callback_request_state_t *	callback_state,
		coap_endpoint_t *	endpoint,
		coap_message_t *	request,
		void(*)(coap_callback_request_state_t *callback_state)	callback )

Send a CoAP request to a remote endpoint.

Parameters

callback_state	The callback state to handle the CoAP request.
endpoint	The destination endpoint.
request	The request to be sent.
callback	callback to execute when the response arrives or the timeout expires.

Returns

1 if there is a transaction available to send, 0 otherwise.

Definition at line 149 of file coap-callback-api.c.

coap_separate_accept()

void coap_separate_accept	(	coap_message_t *	coap_req,
		coap_separate_t *	separate_store )

Initiate a separate response with an empty ACK.

When the server does not have enough resources left to store the information for a separate response, or otherwise cannot execute the resource handler, this function will respond with 5.03 Service Unavailable. The client can then retry later.

Parameters

coap_req	The request to accept.
separate_store	A pointer to the data structure that will store the relevant information for the response.

Definition at line 89 of file coap-separate.c.

References coap_databuf(), coap_endpoint_copy(), and coap_sendto().

coap_separate_reject()

void coap_separate_reject

(

)

Reject a request that would require a separate response with an error message.

When the server does not have enough resources left to store the information for a separate response, or otherwise cannot execute the resource handler, this function will respond with 5.03 Service Unavailable. The client can then retry later.

Definition at line 68 of file coap-separate.c.