/*
* Main request handler: generates response PDU in the provided buffer.
*
* Caller must finish the PDU and send it.
*
* return length of response pdu, or < 0 if can't handle
*/
static size_t _handle_req(coap_pkt_t *pdu, uint8_t *buf, size_t len,
sock_udp_ep_t *remote)
{
coap_resource_t *resource;
gcoap_listener_t *listener;
sock_udp_ep_t *observer = NULL;
gcoap_observe_memo_t *memo = NULL;
gcoap_observe_memo_t *resource_memo = NULL;
_find_resource(pdu, &resource, &listener);
if (resource == NULL) {
return gcoap_response(pdu, buf, len, COAP_CODE_PATH_NOT_FOUND);
}
else {
/* used below to ensure a memo not already recorded for the resource */
_find_obs_memo_resource(&resource_memo, resource);
}
if (coap_get_observe(pdu) == COAP_OBS_REGISTER) {
int empty_slot = _find_obs_memo(&memo, remote, pdu);
/* record observe memo */
if (memo == NULL) {
if (empty_slot >= 0 && resource_memo == NULL) {
int obs_slot = _find_observer(&observer, remote);
/* cache new observer */
if (observer == NULL) {
if (obs_slot >= 0) {
observer = &_coap_state.observers[obs_slot];
memcpy(observer, remote, sizeof(sock_udp_ep_t));
} else {
DEBUG("gcoap: can't register observer\n");
}
}
if (observer != NULL) {
memo = &_coap_state.observe_memos[empty_slot];
}
}
if (memo == NULL) {
coap_clear_observe(pdu);
DEBUG("gcoap: can't register observe memo\n");
}
}
if (memo != NULL) {
memo->observer = observer;
memo->resource = resource;
memo->token_len = coap_get_token_len(pdu);
if (memo->token_len) {
memcpy(&memo->token[0], pdu->token, memo->token_len);
}
DEBUG("gcoap: Registered observer for: %s\n", memo->resource->path);
/* generate initial notification value */
uint32_t now = xtimer_now_usec();
pdu->observe_value = (now >> GCOAP_OBS_TICK_EXPONENT) & 0xFFFFFF;
}
/*
* Main request handler: generates response PDU in the provided buffer.
*
* Caller must finish the PDU and send it.
*
* return length of response pdu, or < 0 if can't handle
*/
static size_t _handle_req(coap_pkt_t *pdu, uint8_t *buf, size_t len,
sock_udp_ep_t *remote)
{
coap_resource_t *resource = NULL;
gcoap_listener_t *listener = NULL;
sock_udp_ep_t *observer = NULL;
gcoap_observe_memo_t *memo = NULL;
gcoap_observe_memo_t *resource_memo = NULL;
switch (_find_resource(pdu, &resource, &listener)) {
case GCOAP_RESOURCE_WRONG_METHOD:
return gcoap_response(pdu, buf, len, COAP_CODE_METHOD_NOT_ALLOWED);
case GCOAP_RESOURCE_NO_PATH:
return gcoap_response(pdu, buf, len, COAP_CODE_PATH_NOT_FOUND);
case GCOAP_RESOURCE_FOUND:
_find_obs_memo_resource(&resource_memo, resource);
break;
}
if (coap_get_observe(pdu) == COAP_OBS_REGISTER) {
int empty_slot = _find_obs_memo(&memo, remote, pdu);
/* record observe memo */
if (memo == NULL) {
if ((resource_memo != NULL)
&& _endpoints_equal(remote, resource_memo->observer)) {
/* observer re-registering with new token */
memo = resource_memo;
observer = resource_memo->observer;
}
else if ((empty_slot >= 0) && (resource_memo == NULL)) {
int obs_slot = _find_observer(&observer, remote);
/* cache new observer */
if (observer == NULL) {
if (obs_slot >= 0) {
observer = &_coap_state.observers[obs_slot];
memcpy(observer, remote, sizeof(sock_udp_ep_t));
} else {
DEBUG("gcoap: can't register observer\n");
}
}
if (observer != NULL) {
memo = &_coap_state.observe_memos[empty_slot];
}
}
if (memo == NULL) {
coap_clear_observe(pdu);
DEBUG("gcoap: can't register observe memo\n");
}
}
if (memo != NULL) {
memo->observer = observer;
memo->resource = resource;
memo->token_len = coap_get_token_len(pdu);
if (memo->token_len) {
memcpy(&memo->token[0], pdu->token, memo->token_len);
}
DEBUG("gcoap: Registered observer for: %s\n", memo->resource->path);
/* generate initial notification value */
uint32_t now = xtimer_now_usec();
pdu->observe_value = (now >> GCOAP_OBS_TICK_EXPONENT) & 0xFFFFFF;
}
