Fix #1930, Null Pointer Check

Fix #1930, add additional coverage test for null pointer check

modules/es/ut-coverage/es_UT.c

@@ -2457,6 +2457,16 @@ void TestGenericPool(void)
     /* Reset the structure so it will rebuild */
     Pool1.TailPosition = 0;
     CFE_UtAssert_SUCCESS(CFE_ES_GenPoolRebuild(&Pool1));
+
+    /* Branch coverage for no buffer in pool */
+    ES_ResetUnitTest();
+    UtAssert_INT32_EQ(CFE_ES_GenPoolCreatePoolBlock(&Pool1, 0, Pool1.Buckets[0].BlockSize, &Offset1),
+                      CFE_ES_BUFFER_NOT_IN_POOL);
+
+    ES_ResetUnitTest();
+    UtAssert_INT32_EQ(CFE_ES_GenPoolRecyclePoolBlock(&Pool1, 0, Pool1.Buckets[0].BlockSize, &Offset1),
+                      CFE_ES_BUFFER_NOT_IN_POOL);
+
 }
 
 void TestTask(void)

modules/es/ut-coverage/es_UT.h

@@ -53,6 +53,7 @@
 #include "cfe_version.h"
 #include "ut_support.h"
 #include "ut_osprintf_stubs.h"
+#include "es_internal_UT.h"
 
 /* ES unit test functions */
 /*****************************************************************************/

modules/es/ut-coverage/es_internal_UT.h

@@ -0,0 +1,45 @@
+/************************************************************************
+ * NASA Docket No. GSC-18,719-1, and identified as “core Flight System: Bootes”
+ *
+ * Copyright (c) 2020 United States Government as represented by the
+ * Administrator of the National Aeronautics and Space Administration.
+ * All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License. You may obtain
+ * a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ ************************************************************************/
+
+ /**
+ * @file
+ *
+ * Purpose:
+ *    Expose internal function for es unit test
+ *
+ * References:
+ *    1. cFE Application Developers Guide
+ *    2. unit test standard 092503
+ *    3. C Coding Standard 102904
+ *
+ * Notes:
+ *    1. This is unit test code only, not for use in flight
+ *
+ */
+
+#ifndef ES_INTERNAL_UT_H
+#define ES_INTERNAL_UT_H
+
+/* Internal ES Function */
+int32 CFE_ES_GenPoolCreatePoolBlock(CFE_ES_GenPoolRecord_t *PoolRecPtr, uint16 BucketId, size_t NewSize, 
+                                    size_t *BlockOffsetPtr);
+
+int32 CFE_ES_GenPoolRecyclePoolBlock(CFE_ES_GenPoolRecord_t *PoolRecPtr, uint16 BucketId, size_t NewSize,
+                                     size_t *BlockOffsetPtr);
+
+#endif /* ES_INTERNAL_UT_H */