API change to allow for post-processing of responses in handle_request().

A pre-defined response is passed as parameter to registered method handlers.
This change was required specifically to use method handlers to generate
observer-notifications.

coap-server.c

@@ -68,10 +68,9 @@ init_coap() {
 
 void 
 hnd_get_time(coap_context_t  *ctx, struct coap_resource_t *resource, 
-	     coap_address_t *peer, coap_pdu_t *request, coap_tid_t id) {
+	     coap_address_t *peer, coap_pdu_t *request, coap_pdu_t *response) {
   coap_opt_iterator_t opt_iter;
   coap_opt_t *token;
-  coap_pdu_t *response;
   size_t size = sizeof(coap_hdr_t) + 32;
   int type;
   unsigned char buf[2];
@@ -84,13 +83,14 @@ hnd_get_time(coap_context_t  *ctx, struct coap_resource_t *resource,
 
   /* if my_clock_base was deleted, we pretend to have no such resource */
   code = my_clock_base ? COAP_RESPONSE_CODE(205) : COAP_RESPONSE_CODE(404);
-
+#if 0
   if (request->hdr->type == COAP_MESSAGE_CON)
     type = COAP_MESSAGE_ACK;
   else 
     type = COAP_MESSAGE_NON;
-
+#endif
   token = coap_check_option(request, COAP_OPTION_TOKEN, &opt_iter);
+#if 0
   if (token)
     size += COAP_OPT_SIZE(token);
 
@@ -100,7 +100,8 @@ hnd_get_time(coap_context_t  *ctx, struct coap_resource_t *resource,
     debug("cannot create response for message %d\n", request->hdr->id);
     return;
   }
-
+#endif
+  response->hdr->code = code;
   if (my_clock_base)
     coap_add_option(response, COAP_OPTION_CONTENT_TYPE,
 		    coap_encode_var_bytes(buf, COAP_MEDIATYPE_TEXT_PLAIN), buf);
@@ -134,11 +135,13 @@ hnd_get_time(coap_context_t  *ctx, struct coap_resource_t *resource,
 				 "%u", (unsigned int)now);
   }
 
+#if 0
   if (coap_send(ctx, peer, response) == COAP_INVALID_TID) {
     debug("hnd_get_time: cannot send response for message %d\n", 
 	  request->hdr->id);
     coap_delete_pdu(response);
   }
+#endif
 }
 
 void

net.c

@@ -821,7 +821,22 @@ handle_request(coap_context_t *context, coap_queue_t *node) {
   if (h) {
     debug("call custom handler for resource 0x%02x%02x%02x%02x\n", 
 	  key[0], key[1], key[2], key[3]);
-    h(context, resource, &node->remote, node->pdu, node->id);
+    response = coap_pdu_init(node->pdu->hdr->type == COAP_MESSAGE_CON 
+			     ? COAP_MESSAGE_ACK
+			     : COAP_MESSAGE_NON,
+			     0, node->pdu->hdr->id, COAP_MAX_PDU_SIZE);
+    if (response) {
+      h(context, resource, &node->remote, node->pdu, response);
+      if (response->hdr->type != COAP_MESSAGE_NON ||
+	  response->hdr->code >= 64) {
+	if (coap_send(context, &node->remote, response) == COAP_INVALID_TID) {
+	  debug("cannot send response for message %d\n", node->pdu->hdr->id);
+	}
+      }
+      coap_delete_pdu(response);
+    } else {
+      warn("cannot generate response\r\n");
+    }
   } else {
     if (WANT_WKC(node->pdu, key)) {
       debug("create default response for %s\n", COAP_DEFAULT_URI_WELLKNOWN);

resource.h

@@ -35,7 +35,7 @@
 /** Definition of message handler function (@sa coap_resource_t). */
 typedef void (*coap_method_handler_t)
   (coap_context_t  *, struct coap_resource_t *, coap_address_t *, coap_pdu_t *,
-   coap_tid_t);
+   coap_pdu_t *);
 
 typedef struct coap_attr_t {
   struct coap_attr_t *next;