Handle upgrade header (FreeRTOS#159)

* handle upgrade header, update unit tests

* update review comments

* fix review comments

Author: tony-josi-aws

source/core_http_client.c

@@ -1050,6 +1050,7 @@ static HTTPStatus_t processLlhttpError( const llhttp_t * pHttpParser )
     switch( llhttp_get_errno( pHttpParser ) )
     {
         case HPE_OK:
+        case HPE_PAUSED_UPGRADE:
             /* There were no errors. */
             break;
 
@@ -1158,6 +1159,7 @@ static HTTPStatus_t parseHttpResponse( HTTPParsingContext_t * pParsingContext,
 {
     HTTPStatus_t returnStatus;
     const char * parsingStartLoc = NULL;
+    llhttp_errno_t eReturn;
 
     assert( pParsingContext != NULL );
     assert( pResponse != NULL );
@@ -1202,8 +1204,13 @@ static HTTPStatus_t parseHttpResponse( HTTPParsingContext_t * pParsingContext,
 
     /* This will begin the parsing. Each of the callbacks set in
      * parserSettings will be invoked as parts of the HTTP response are
-     * reached. The return code is parsed in #processLlhttpError so is not needed. */
-    ( void ) llhttp_execute( &( pParsingContext->llhttpParser ), parsingStartLoc, parseLen );
+     * reached. The return code is parsed in #processLlhttpError. */
+    eReturn = llhttp_execute( &( pParsingContext->llhttpParser ), parsingStartLoc, parseLen );
+
+    if( eReturn == HPE_PAUSED_UPGRADE )
+    {
+        llhttp_resume_after_upgrade( &( pParsingContext->llhttpParser ) );
+    }
 
     /* The next location to parse will always be after what has already
      * been parsed. */

test/unit-test/core_http_send_utest.c

@@ -561,6 +561,25 @@ static llhttp_errno_t llhttp_execute_whole_response( llhttp_t * pParser,
     return HPE_OK;
 }
 
+/* Mocked llhttp_execute callback that expects upgrade header in HTTP response. */
+static llhttp_errno_t llhttp_execute_paused_upgrade( llhttp_t * pParser,
+                                                     const char * pData,
+                                                     size_t len,
+                                                     int cmock_num_calls )
+{
+    ( void ) cmock_num_calls;
+    llhttp_errno_t eReturn = HPE_OK;
+
+    if( httpParserExecuteCallCount == 0 )
+    {
+        eReturn = HPE_PAUSED_UPGRADE;
+    }
+
+    llhttp_execute_whole_response( pParser, pData, len, 0 );
+
+    return eReturn;
+}
+
 /* Mocked llhttp_execute callback that will be called the first time on the
  * response message up to the middle of the first header field, then the second
  * time on the response message from the middle of the first header field to the
@@ -1374,6 +1393,26 @@ void test_HTTPClient_Send_less_bytes_request_body( void )
 
 /*-----------------------------------------------------------*/
 
+/* Test upgrade header in HTTP response. */
+void test_HTTPClient_Send_paused_upgrade( void )
+{
+    HTTPStatus_t returnStatus = HTTPSuccess;
+
+    llhttp_execute_Stub( llhttp_execute_paused_upgrade );
+    llhttp_resume_after_upgrade_ExpectAnyArgs();
+
+    returnStatus = HTTPClient_Send( &transportInterface,
+                                    &requestHeaders,
+                                    NULL,
+                                    0,
+                                    &response,
+                                    0 );
+
+    TEST_ASSERT_EQUAL( HTTPSuccess, returnStatus );
+}
+
+/*-----------------------------------------------------------*/
+
 /* Test when a network error is returned when receiving the response. */
 void test_HTTPClient_Send_network_error_response( void )
 {