Update mbed-coap to version 4.6.2

Do not clear block2 in subsequent block request.

When sending a request with block2 option, eg. indicating need
for response to be blockwised, copy the block2 option from the
sent_blockwise list item so that the block2 option will be added
to all requests. This fixes an issue where previously the block2
was only sent for the first blockwise request and not for the
subsequent ones, including the last request. This made the response
not follow the request block2 option.

Author: Antti Yli-Tokola

features/frameworks/mbed-coap/CHANGELOG.md

@@ -1,5 +1,19 @@
 # Change Log
 
+## [v4.6.2](https://github.com/ARMmbed/mbed-coap/releases/tag/v4.6.2) 
+
+Do not clear block2 in subsequent block request.
+
+When sending a request with block2 option, eg. indicating need
+for response to be blockwised, copy the block2 option from the
+sent_blockwise list item so that the block2 option will be added
+to all requests. This fixes an issue where previously the block2
+was only sent for the first blockwise request and not for the
+subsequent ones, including the last request. This made the response
+not follow the request block2 option.
+
+-[Full Changelog](https://github.com/ARMmbed/mbed-coap/compare/v4.6.1...v4.6.2)
+
 ## [v4.6.1](https://github.com/ARMmbed/mbed-coap/releases/tag/v4.6.1) 
 **Closed issues:**
 -  IOTCLT-2900 - Blockwise handling leaking memory in some error cases

features/frameworks/mbed-coap/module.json

@@ -1,6 +1,6 @@
 {
   "name": "mbed-coap",
-  "version": "4.6.1",
+  "version": "4.6.2",
   "description": "COAP library",
   "keywords": [
     "coap",

features/frameworks/mbed-coap/source/sn_coap_protocol.c

@@ -1796,7 +1796,8 @@ static sn_coap_hdr_s *sn_coap_handle_blockwise_message(struct coap_s *handle, sn
 
                     if (src_coap_blockwise_ack_msg_ptr->options_list_ptr) {
                         src_coap_blockwise_ack_msg_ptr->options_list_ptr->block1 = COAP_OPTION_BLOCK_NONE;
-                        src_coap_blockwise_ack_msg_ptr->options_list_ptr->block2 = COAP_OPTION_BLOCK_NONE;
+                        // Do not clear block2 as it might have been set in the original request to request
+                        // specific size blocks
                     } else {
                         if (!sn_coap_parser_alloc_options(handle, src_coap_blockwise_ack_msg_ptr)) {
                             tr_error("sn_coap_handle_blockwise_message - (send block1) failed to allocate ack message!");
@@ -1823,6 +1824,7 @@ static sn_coap_hdr_s *sn_coap_handle_blockwise_message(struct coap_s *handle, sn
                         src_coap_blockwise_ack_msg_ptr->payload_len = block_size;
                         src_coap_blockwise_ack_msg_ptr->payload_ptr = src_coap_blockwise_ack_msg_ptr->payload_ptr + (block_size * block_number);
                     }
+
                     /* Build and send block message */
                     dst_packed_data_needed_mem = sn_coap_builder_calc_needed_packet_data_size_2(src_coap_blockwise_ack_msg_ptr, handle->sn_coap_block_data_size);
 
@@ -2245,7 +2247,8 @@ static sn_coap_hdr_s *sn_coap_handle_blockwise_message(struct coap_s *handle, sn
 
                 if (src_coap_blockwise_ack_msg_ptr->options_list_ptr) {
                     src_coap_blockwise_ack_msg_ptr->options_list_ptr->block1 = COAP_OPTION_BLOCK_NONE;
-                    src_coap_blockwise_ack_msg_ptr->options_list_ptr->block2 = COAP_OPTION_BLOCK_NONE;
+                    // Do not clear block2 as it might have been set in the original request to request
+                    // specific size blocks
                 } else {
                     if (sn_coap_parser_alloc_options(handle, src_coap_blockwise_ack_msg_ptr) == NULL) {
                         tr_error("sn_coap_handle_blockwise_message - (recv block2) failed to allocate options!");