Adding unit tests for stream buffer and message buffer (#528)

* Initial commit

* Add more stream buffer tests

* Adding message buffer tests

* Adding tests to cover config assert branches

Co-authored-by: alfred gedeon <28123637+alfred2g@users.noreply.github.com>

FreeRTOS/Test/CMock/Makefile

@@ -10,6 +10,8 @@ export LD ?= /usr/local/bin/ld
 UNITS       +=  list
 #UNITS       +=  queue
 #UNITS       += timers
+UNITS       +=  stream_buffer
+UNITS       +=  message_buffer
 
 COVINFO     :=  $(BUILD_DIR)/cmock_test.info
 LCOV_LIST   :=  $(foreach unit,$(UNITS),$(GENERATED_DIR)/$(unit).info )

FreeRTOS/Test/CMock/message_buffer/Makefile

@@ -0,0 +1,43 @@
+# indent with spaces
+.RECIPEPREFIX := $(.RECIPEPREFIX) $(.RECIPEPREFIX)
+
+# Do not move this line below the include
+MAKEFILE_ABSPATH    :=  $(abspath $(lastword $(MAKEFILE_LIST)))
+include ../makefile.in
+
+# PROJECT_SRC lists the .c files under test
+PROJECT_SRC         :=  stream_buffer.c
+
+# PROJECT_DEPS_SRC list the .c file that are dependencies of PROJECT_SRC files
+# Files in PROJECT_DEPS_SRC are excluded from coverage measurements
+PROJECT_DEPS_SRC    :=
+
+# PROJECT_HEADER_DEPS: headers that should be excluded from coverage measurements.
+PROJECT_HEADER_DEPS :=  FreeRTOS.h
+
+# SUITE_UT_SRC: .c files that contain test cases (must end in _utest.c)
+SUITE_UT_SRC        :=  message_buffer_utest.c
+
+# SUITE_SUPPORT_SRC: .c files used for testing that do not contain test cases.
+# Paths are relative to PROJECT_DIR
+SUITE_SUPPORT_SRC   :=
+
+# List the headers used by PROJECT_SRC that you would like to mock
+MOCK_FILES_FP      :=  $(KERNEL_DIR)/include/task.h
+MOCK_FILES_FP      +=  $(UT_ROOT_DIR)/config/fake_assert.h
+MOCK_FILES_FP      +=  $(UT_ROOT_DIR)/config/fake_port.h
+
+# List any addiitonal flags needed by the preprocessor
+CPPFLAGS            +=  -DportUSING_MPU_WRAPPERS=0
+
+# List any addiitonal flags needed by the compiler
+CFLAGS              +=
+
+# Try not to edit beyond this line unless necessary.
+
+# Project is determined based on path: $(UT_ROOT_DIR)/$(PROJECT)
+PROJECT         :=  $(lastword $(subst /, ,$(dir $(abspath $(MAKEFILE_ABSPATH)))))
+
+export
+
+include ../testdir.mk

FreeRTOS/Test/CMock/message_buffer/message_buffer.yml

@@ -0,0 +1,32 @@
+:cmock:
+  :mock_prefix: mock_
+  :when_no_prototypes: :warn
+  :treat_externs: :include
+  :enforce_strict_ordering: TRUE
+  :plugins:
+    - :ignore
+    - :ignore_arg
+    - :expect_any_args
+    - :array
+    - :callback
+    - :return_thru_ptr
+  :callback_include_count: true # include a count arg when calling the callback
+  :callback_after_arg_check: false # check arguments before calling the callback
+  :treat_as:
+    uint8:    HEX8
+    uint16:   HEX16
+    uint32:   UINT32
+    int8:     INT8
+    bool:     UINT8
+  :includes:        # This will add these includes to each mock.
+    - <stdbool.h>
+    - "FreeRTOS.h"
+  :treat_externs: :exclude  # Now the extern-ed functions will be mocked.
+  :weak: __attribute__((weak))
+  :verbosity: 3
+  :attributes:
+    - PRIVILEGED_FUNCTION
+  :strippables:
+    - PRIVILEGED_FUNCTION
+    - portDONT_DISCARD
+  :treat_externs: :include

FreeRTOS/Test/CMock/message_buffer/message_buffer_utest.c

@@ -0,0 +1,795 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+/*! @file message_buffer_utest.c */
+
+/* C runtime includes. */
+#include <stdlib.h>
+#include <stdbool.h>
+
+/* Queue includes */
+#include "FreeRTOS.h"
+#include "FreeRTOSConfig.h"
+#include "message_buffer.h"
+
+/* Test includes. */
+#include "unity.h"
+#include "unity_memory.h"
+
+/* Mock includes. */
+#include "mock_task.h"
+#include "mock_fake_assert.h"
+#include "mock_fake_port.h"
+
+/**
+ * @brief Sample size in bytes of the message buffer used for test.
+ * Keep it short enough so that they can be allocated on stack.
+ */
+#define TEST_MESSAGE_BUFFER_SIZE             ( 64U )
+
+/**
+ * @brief Minimum size required to store the length of the message.
+ */
+#define TEST_MESSAGE_METADATA_SIZE           ( sizeof( configMESSAGE_BUFFER_LENGTH_TYPE ) )
+
+/**
+ * @brief Maximum size of a message that can be sent to a message buffer.
+ * Each message stores an associated length of the message as metadata. So maximum message
+ * size at any time is total length - size of the variable used to store length.
+ */
+#define TEST_MAX_MESSAGE_SIZE                ( TEST_MESSAGE_BUFFER_SIZE - TEST_MESSAGE_METADATA_SIZE )
+
+/**
+ * @brief Maximum unsigned long value so as to trigger an integer overflow.
+ */
+#define TEST_MESSAGE_BUFFER_MAX_UINT_SIZE    ( ~( size_t ) ( 0UL ) )
+
+/**
+ * @brief Ticks to wait from tests if the message buffer is full while sending data or
+ * below trigger level while receiveing data.
+ */
+#define TEST_MESSAGE_BUFFER_WAIT_TICKS       ( 1000U )
+
+/* ============================  GLOBAL VARIABLES =========================== */
+
+/**
+ * @brief Global counter for the number of assertions in code.
+ */
+static int assertionFailed = 0;
+
+/**
+ * @brief Global counter to keep track of how many times a sender task was woken up by a task receiving from the stream buffer.
+ */
+static int senderTaskWoken = 0;
+
+/**
+ * @brief Global counter to keep track of how many times a receiver task was woken up by a task sending to the buffer.
+ */
+static int receiverTaskWoken = 0;
+
+/**
+ * @brief Dummy sender task handle to which the stream buffer receive APIs will send notification.
+ */
+static TaskHandle_t senderTask = ( TaskHandle_t ) ( 0xAABBCCDD );
+
+/**
+ * @brief Dummy receiver task handle to which the stream buffer send APIs will send notifications.
+ */
+static TaskHandle_t receiverTask = ( TaskHandle_t ) ( 0xABCDEEFF );
+
+/**
+ * @brief Global message buffer handle used for tests.
+ */
+static MessageBufferHandle_t xMessageBuffer;
+
+/**
+ * @brief Flag which denotes if test need to abort on assertion.
+ */
+static BaseType_t shouldAbortOnAssertion;
+
+/* ==========================  CALLBACK FUNCTIONS =========================== */
+
+void * pvPortMalloc( size_t xSize )
+{
+    return unity_malloc( xSize );
+}
+void vPortFree( void * pv )
+{
+    return unity_free( pv );
+}
+
+static void vFakeAssertStub( bool x,
+                             char * file,
+                             int line,
+                             int cmock_num_calls )
+{
+    if( !x )
+    {
+        assertionFailed++;
+
+        if( shouldAbortOnAssertion == pdTRUE )
+        {
+            TEST_ABORT();
+        }
+    }
+}
+
+static BaseType_t senderTaskNotificationCallback( TaskHandle_t xTaskToNotify,
+                                                  UBaseType_t uxIndexToNotify,
+                                                  uint32_t ulValue,
+                                                  eNotifyAction eAction,
+                                                  uint32_t * pulPreviousNotificationValue,
+                                                  int cmock_num_calls )
+{
+    TEST_ASSERT_EQUAL( senderTask, xTaskToNotify );
+    senderTaskWoken++;
+    return pdTRUE;
+}
+
+static BaseType_t messageBufferReceiveFromISRCallback( UBaseType_t uxIndexToWaitOn,
+                                                       uint32_t ulBitsToClearOnEntry,
+                                                       uint32_t ulBitsToClearOnExit,
+                                                       uint32_t * pulNotificationValue,
+                                                       TickType_t xTicksToWait,
+                                                       int cmock_num_calls )
+{
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t dataReceived = 0;
+    BaseType_t senderTaskWokenFromISR = pdFALSE;
+
+    dataReceived = xMessageBufferReceiveFromISR( xMessageBuffer, data, TEST_MAX_MESSAGE_SIZE, &senderTaskWokenFromISR );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, dataReceived );
+    return pdTRUE;
+}
+
+static BaseType_t messageBufferReceiveCallback( UBaseType_t uxIndexToWaitOn,
+                                                uint32_t ulBitsToClearOnEntry,
+                                                uint32_t ulBitsToClearOnExit,
+                                                uint32_t * pulNotificationValue,
+                                                TickType_t xTicksToWait,
+                                                int cmock_num_calls )
+{
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t dataReceived = 0;
+
+    /* Read next message from message buffer to wake up sender task. */
+    dataReceived = xMessageBufferReceive( xMessageBuffer, data, TEST_MAX_MESSAGE_SIZE, 0 );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, dataReceived );
+    return pdTRUE;
+}
+
+static BaseType_t messageBufferSendFromISRCallback( UBaseType_t uxIndexToWaitOn,
+                                                    uint32_t ulBitsToClearOnEntry,
+                                                    uint32_t ulBitsToClearOnExit,
+                                                    uint32_t * pulNotificationValue,
+                                                    TickType_t xTicksToWait,
+                                                    int cmock_num_calls )
+{
+    BaseType_t receiverTaskWokenFromISR = pdFALSE;
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t dataSent = 0;
+
+    dataSent = xMessageBufferSendFromISR( xMessageBuffer, data, TEST_MAX_MESSAGE_SIZE, &receiverTaskWokenFromISR );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, dataSent );
+    return pdTRUE;
+}
+
+static BaseType_t messageBufferSendCallback( UBaseType_t uxIndexToWaitOn,
+                                             uint32_t ulBitsToClearOnEntry,
+                                             uint32_t ulBitsToClearOnExit,
+                                             uint32_t * pulNotificationValue,
+                                             TickType_t xTicksToWait,
+                                             int cmock_num_calls )
+{
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t dataSent = 0;
+
+    /* Send a single message of max message size to message buffer to wake up receiver Task. */
+    dataSent = xMessageBufferSend( xMessageBuffer, data, TEST_MAX_MESSAGE_SIZE, 0 );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, dataSent );
+    return pdTRUE;
+}
+
+static BaseType_t receiverTaskNotificationCallback( TaskHandle_t xTaskToNotify,
+                                                    UBaseType_t uxIndexToNotify,
+                                                    uint32_t ulValue,
+                                                    eNotifyAction eAction,
+                                                    uint32_t * pulPreviousNotificationValue,
+                                                    int cmock_num_calls )
+{
+    TEST_ASSERT_EQUAL( receiverTask, xTaskToNotify );
+    receiverTaskWoken++;
+    return pdTRUE;
+}
+
+/*******************************************************************************
+ * Unity fixtures
+ ******************************************************************************/
+void setUp( void )
+{
+    assertionFailed = 0;
+    xMessageBuffer = NULL;
+    senderTaskWoken = 0;
+    receiverTaskWoken = 0;
+    shouldAbortOnAssertion = pdTRUE;
+
+    mock_task_Init();
+    mock_fake_assert_Init();
+    mock_fake_port_Init();
+
+    vFakePortEnterCriticalSection_Ignore();
+    vFakePortExitCriticalSection_Ignore();
+    ulFakePortSetInterruptMaskFromISR_IgnoreAndReturn( 0U );
+    vFakePortClearInterruptMaskFromISR_Ignore();
+    vFakeAssert_StubWithCallback( vFakeAssertStub );
+    /* Track calls to malloc / free */
+    UnityMalloc_StartTest();
+}
+
+/*! called before each testcase */
+void tearDown( void )
+{
+    TEST_ASSERT_EQUAL_MESSAGE( 0, assertionFailed, "Assertion check failed in code." );
+    UnityMalloc_EndTest();
+
+    mock_task_Verify();
+    mock_task_Destroy();
+
+    mock_fake_assert_Verify();
+    mock_fake_assert_Destroy();
+
+    mock_fake_port_Verify();
+    mock_fake_port_Destroy();
+}
+
+/*! called at the beginning of the whole suite */
+void suiteSetUp()
+{
+}
+
+/*! called at the end of the whole suite */
+int suiteTearDown( int numFailures )
+{
+    return numFailures;
+}
+
+static void validate_message_buffer_init_state( MessageBufferHandle_t xMessageBuffer,
+                                                size_t bufferSize )
+{
+    TEST_ASSERT_TRUE( xMessageBufferIsEmpty( xMessageBuffer ) );
+    TEST_ASSERT_FALSE( xMessageBufferIsFull( xMessageBuffer ) );
+    TEST_ASSERT_EQUAL( bufferSize, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+    TEST_ASSERT_EQUAL( 0, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+    TEST_ASSERT_EQUAL( 1, ucStreamBufferGetStreamBufferType( xMessageBuffer ) );
+}
+
+static void validate_and_clear_assertions( void )
+{
+    TEST_ASSERT_EQUAL( 1, assertionFailed );
+    assertionFailed = 0;
+}
+
+/* ==============================  Test Cases  ============================== */
+
+/**
+ * @brief Validates that message buffer of sample test size is created successfully.
+ */
+void test_xMessageBufferCreate_success( void )
+{
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_EQUAL( NULL, xMessageBuffer );
+    validate_message_buffer_init_state( xMessageBuffer, TEST_MESSAGE_BUFFER_SIZE );
+    vMessageBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief API should fail and return null if there is an integer overflow in message buffer size passed.
+ */
+void test_xMessageBufferCreate_integer_overflow( void )
+{
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_MAX_UINT_SIZE );
+    TEST_ASSERT_EQUAL( NULL, xMessageBuffer );
+}
+
+/**
+ * @breif API should fail and return null if the malloc fails.
+ */
+void test_xMessageBufferCreate_malloc_fail( void )
+{
+    UnityMalloc_MakeMallocFailAfterCount( 0 );
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NULL( xMessageBuffer );
+}
+
+/**
+ * @brief Should assert if a zero size is passed to create API.
+ */
+void test_xMessageBufferCreate_zero_size( void )
+{
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferCreate( 0 );
+    }
+
+    validate_and_clear_assertions();
+}
+
+/**
+ * @brief Should assert if the size passed is less than the minimum size requried to store metadata size.
+ */
+void test_xMessageBufferCreate_invalid_size( void )
+{
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferCreate( TEST_MESSAGE_METADATA_SIZE );
+    }
+
+    validate_and_clear_assertions();
+}
+
+/**
+ * @brief Validates message buffer creation through a static buffer allocated by the user.
+ */
+void test_xMessageBufferCreateStatic_success( void )
+{
+    StaticMessageBuffer_t messageBufferStruct;
+    /* The size of message buffer array should be one greater than the required size of message buffer. */
+    uint8_t messageBufferArray[ TEST_MESSAGE_BUFFER_SIZE + 1 ] = { 0 };
+
+    xMessageBuffer = xMessageBufferCreateStatic( sizeof( messageBufferArray ), messageBufferArray, &messageBufferStruct );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+
+    validate_message_buffer_init_state( xMessageBuffer, TEST_MESSAGE_BUFFER_SIZE );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates message buffer creation fails if null array is passed.
+ */
+void test_xMessageBufferCreateStatic_null_array( void )
+{
+    StaticMessageBuffer_t messageBufferStruct;
+
+    /* Tests should abort if assertion is enabled or return NULL. */
+    shouldAbortOnAssertion = pdFALSE;
+
+    /* Returns NULL when NULL storage area is passed as a parameter. */
+    xMessageBuffer = xMessageBufferCreateStatic( TEST_MESSAGE_BUFFER_SIZE, NULL, &messageBufferStruct );
+    TEST_ASSERT_NULL( xMessageBuffer );
+    validate_and_clear_assertions();
+}
+
+/**
+ * @brief Validates message buffer creation fails if NULL struct is passed.
+ */
+void test_xMessageBufferCreateStatic_null_struct( void )
+{
+    /* The size of message buffer array should be one greater than the required size of message buffer. */
+    uint8_t messageBufferArray[ TEST_MESSAGE_BUFFER_SIZE + 1 ] = { 0 };
+
+    /* Tests should abort if assertion is enabled or return NULL. */
+    shouldAbortOnAssertion = pdFALSE;
+
+    /* Returns NULL when NULL message buffer struct is passed as a parameter. */
+    xMessageBuffer = xMessageBufferCreateStatic( sizeof( messageBufferArray ), messageBufferArray, NULL );
+    TEST_ASSERT_NULL( xMessageBuffer );
+    validate_and_clear_assertions();
+}
+
+/**
+ * @brief Validates message buffer create assert if the size passed is less than the minimum size requried to store metadata size.
+ */
+void test_xMessageBufferCreateStatic_invalid_size( void )
+{
+    StaticMessageBuffer_t messageBufferStruct;
+    /* The size of message buffer array should be one greater than the required size of message buffer. */
+    uint8_t messageBufferArray[ TEST_MESSAGE_BUFFER_SIZE + 1 ] = { 0 };
+
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferCreateStatic( TEST_MESSAGE_METADATA_SIZE, messageBufferArray, &messageBufferStruct );
+    }
+
+    validate_and_clear_assertions();
+}
+
+/**
+ * @brief Validate message buffer creation asserts if the size passed is zero.
+ */
+void test_xMessageBufferCreateStatic_zero_size( void )
+{
+    StaticMessageBuffer_t messageBufferStruct;
+    /* The size of message buffer array should be one greater than the required size of message buffer. */
+    uint8_t messageBufferArray[ TEST_MESSAGE_BUFFER_SIZE + 1 ] = { 0 };
+
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferCreateStatic( 0, messageBufferArray, &messageBufferStruct );
+    }
+
+    validate_and_clear_assertions();
+}
+
+/**
+ * @brief Validates a task is able to send upto maximum message size allowed, without blocking.
+ */
+void test_xMessageBufferSend_success( void )
+{
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t dataSent = 0;
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of the default test sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    /* Sending bytes of size  upto to available size should succeed. Sender task should not be in blocked state. */
+    dataSent = xMessageBufferSend( xMessageBuffer, data, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, dataSent );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+    TEST_ASSERT_EQUAL( pdFALSE, xMessageBufferIsEmpty( xMessageBuffer ) );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief An integer overflow in message size to be sent should result in an
+ * assertion failure 
+ */
+void test_xMessageBufferSend_message_size_integer_overflow( void )
+{
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of the default test sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferSend( xMessageBuffer, data, TEST_MESSAGE_BUFFER_MAX_UINT_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    }
+    validate_and_clear_assertions();
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * Sending a message of size greater than available size should return zero bytes sent.
+ */
+void test_xMessageBufferSend_message_larger_than_available_size( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE + 1 ] = { 0 };
+    size_t sentBytes = 0;
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    sentBytes = xMessageBufferSend( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE + 1, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( 0, sentBytes );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Sending null message should trigger an assert.
+ */
+void test_xMessageBufferSend_null_message( void )
+{
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferSend( xMessageBuffer, NULL, TEST_MAX_MESSAGE_SIZE + 1, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    }
+
+    validate_and_clear_assertions();
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Sending to a null message buffer should trigger an assert.
+ */
+void test_xMessageBufferSend_null_message_buffer( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE + 1 ] = { 0 };
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferSend( NULL, message, TEST_MAX_MESSAGE_SIZE + 1, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    }
+
+    validate_and_clear_assertions();
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates that a task blocks if there is insufficient space in message buffer for a valid message to be sent.
+ * Task then succeeds once enough space is available by reading from the message buffer.
+ */
+void test_xMessageBufferSend_blocking( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t sentBytes = 0;
+
+    vTaskSetTimeOutState_Ignore();
+    xTaskGenericNotifyStateClear_IgnoreAndReturn( pdTRUE );
+    xTaskGetCurrentTaskHandle_IgnoreAndReturn( senderTask );
+    xTaskGenericNotifyWait_StubWithCallback( messageBufferReceiveCallback );
+    xTaskGenericNotify_StubWithCallback( senderTaskNotificationCallback );
+    xTaskCheckForTimeOut_IgnoreAndReturn( pdFALSE );
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    /* Sending max message size so that message buffer is full. */
+    sentBytes = xMessageBufferSend( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, sentBytes );
+    TEST_ASSERT_EQUAL( 0, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    /* Sending max message size again blocks the task. API succeeds after reading the current message from the buffer. */
+    sentBytes = xMessageBufferSend( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, sentBytes );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+    TEST_ASSERT_EQUAL( 1, senderTaskWoken );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates a task is able to receive upto maximum message size allowed, without blocking.
+ */
+void test_xMessageBufferReceive_success( void )
+{
+    uint8_t data[ TEST_MAX_MESSAGE_SIZE ] = { 0xAA };
+    size_t sent = 0;
+    uint8_t dataReceived[ TEST_MAX_MESSAGE_SIZE + 1 ] = { 0x00 };
+    size_t received = 0;
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of the default test sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    sent = xMessageBufferSend( xMessageBuffer, data, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, sent );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+
+    /* Receiving bytes of size less than the message length will return 0 bytes. */
+    received = xMessageBufferReceive( xMessageBuffer, dataReceived, TEST_MAX_MESSAGE_SIZE - 1, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( 0, received );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+
+    /* Receiving bytes of size greater than the message length will return message length bytes. */
+    received = xMessageBufferReceive( xMessageBuffer, dataReceived, TEST_MAX_MESSAGE_SIZE + 1, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, received );
+    TEST_ASSERT_EQUAL( 0, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates xMessageBufferReceive API with null input message.
+ */
+void test_xMessageBufferReceive_null_input_message( void )
+{
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+
+    /* Should assert if a null input mssage is passed. */
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferReceive( xMessageBuffer, NULL, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    }
+
+    validate_and_clear_assertions();
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+
+/**
+ * @brief Validates xMessageBufferReceive API with null message buffer handle.
+ */
+void test_xMessageBufferReceive_invalid_params( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+
+    /* Should assert if a null message buffer handle is passed. */
+    if( TEST_PROTECT() )
+    {
+        ( void ) xMessageBufferReceive( NULL, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    }
+
+    validate_and_clear_assertions();
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates that a task blocks if trying to read from an empty buffer.
+ * Task  succeeds once a message is sent to message buffer.
+ */
+void test_xMessageBufferReceive_blocking( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t received = 0;
+
+    vTaskSetTimeOutState_Ignore();
+    xTaskGenericNotifyStateClear_IgnoreAndReturn( pdTRUE );
+    xTaskGetCurrentTaskHandle_IgnoreAndReturn( receiverTask );
+    xTaskGenericNotifyWait_StubWithCallback( messageBufferSendCallback );
+    xTaskGenericNotify_StubWithCallback( receiverTaskNotificationCallback );
+    xTaskCheckForTimeOut_IgnoreAndReturn( pdFALSE );
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    /* Receive from an empty buffer causes task to block. API succeeds after a message is sent to buffer. */
+    received = xMessageBufferReceive( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, received );
+    TEST_ASSERT_EQUAL( 0, xStreamBufferNextMessageLengthBytes( xMessageBuffer ) );
+    TEST_ASSERT_EQUAL( 1, receiverTaskWoken );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates that xMessageBufferSendFromISR API is successful and unblocks a receive task.
+ */
+void test_xMessageBufferSendFromISR_success( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t received = 0, sent = 0;
+    BaseType_t highPriorityTaskWoken = pdFALSE;
+
+    vTaskSetTimeOutState_Ignore();
+    xTaskGenericNotifyStateClear_IgnoreAndReturn( pdTRUE );
+    xTaskGetCurrentTaskHandle_IgnoreAndReturn( receiverTask );
+    xTaskGenericNotifyWait_StubWithCallback( messageBufferSendFromISRCallback );
+    xTaskGenericNotifyFromISR_IgnoreAndReturn( pdTRUE );
+    xTaskCheckForTimeOut_IgnoreAndReturn( pdFALSE );
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( TEST_MESSAGE_BUFFER_SIZE, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    /* Receiving from empty message buffer should block. But the task be woken up from a send from ISR. */
+    received = xMessageBufferReceive( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, received );
+
+
+    /* Sending message of max size from ISR should succeed. */
+    sent = xMessageBufferSendFromISR( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, &highPriorityTaskWoken );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, received );
+
+    /* Sending message of max size again from ISR should return zero instead of blocking. */
+    sent = xMessageBufferSendFromISR( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, &highPriorityTaskWoken );
+    TEST_ASSERT_EQUAL( 0, sent );
+
+    vStreamBufferDelete( xMessageBuffer );
+}
+
+/**
+ * @brief Validates that xMessageBufferSendFromISR API is successful and unblocks a receive task.
+ */
+void test_xMessageBufferReceiveFromISR_success( void )
+{
+    uint8_t message[ TEST_MAX_MESSAGE_SIZE ] = { 0 };
+    size_t sent = 0, received = 0;
+    BaseType_t xHighPriorityTaskWoken = pdFALSE;
+
+    vTaskSetTimeOutState_Ignore();
+    vTaskSuspendAll_Ignore();
+    xTaskResumeAll_IgnoreAndReturn( pdTRUE );
+
+    /* Create a message buffer of sample size. */
+    xMessageBuffer = xMessageBufferCreate( TEST_MESSAGE_BUFFER_SIZE );
+    TEST_ASSERT_NOT_NULL( xMessageBuffer );
+    TEST_ASSERT_EQUAL( pdTRUE, xMessageBufferIsEmpty( xMessageBuffer ) );
+
+    /* Receiving from an empty message buffer from ISR should not block but return 0 bytes. */
+    received = xMessageBufferReceiveFromISR( xMessageBuffer, message, TEST_MESSAGE_BUFFER_SIZE, &xHighPriorityTaskWoken );
+    TEST_ASSERT_EQUAL( 0, received );
+
+    xTaskGenericNotifyStateClear_IgnoreAndReturn( pdTRUE );
+    xTaskGetCurrentTaskHandle_IgnoreAndReturn( senderTask );
+    xTaskGenericNotifyWait_StubWithCallback( messageBufferReceiveFromISRCallback );
+    xTaskGenericNotifyFromISR_IgnoreAndReturn( pdTRUE );
+    xTaskCheckForTimeOut_IgnoreAndReturn( pdFALSE );
+
+    /* Sending max message size so that message buffer is full. */
+    sent = xMessageBufferSend( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, sent );
+    TEST_ASSERT_EQUAL( 0, xMessageBufferSpacesAvailable( xMessageBuffer ) );
+
+    /* Receiving using a smaller buffer size from ISR should not block and return 0 bytes. */
+    received = xMessageBufferReceiveFromISR( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE - 1, &xHighPriorityTaskWoken );
+    TEST_ASSERT_EQUAL( 0, received );
+
+    /* Sending max message size again should block, but task should be woken up after receiving message from ISR. */
+    sent = xMessageBufferSend( xMessageBuffer, message, TEST_MAX_MESSAGE_SIZE, TEST_MESSAGE_BUFFER_WAIT_TICKS );
+    TEST_ASSERT_EQUAL( TEST_MAX_MESSAGE_SIZE, sent );
+
+    vStreamBufferDelete( xMessageBuffer );
+}

FreeRTOS/Test/CMock/stream_buffer/Makefile

@@ -0,0 +1,43 @@
+# indent with spaces
+.RECIPEPREFIX := $(.RECIPEPREFIX) $(.RECIPEPREFIX)
+
+# Do not move this line below the include
+MAKEFILE_ABSPATH    :=  $(abspath $(lastword $(MAKEFILE_LIST)))
+include ../makefile.in
+
+# PROJECT_SRC lists the .c files under test
+PROJECT_SRC         :=  stream_buffer.c
+
+# PROJECT_DEPS_SRC list the .c file that are dependencies of PROJECT_SRC files
+# Files in PROJECT_DEPS_SRC are excluded from coverage measurements
+PROJECT_DEPS_SRC    :=
+
+# PROJECT_HEADER_DEPS: headers that should be excluded from coverage measurements.
+PROJECT_HEADER_DEPS :=  FreeRTOS.h
+
+# SUITE_UT_SRC: .c files that contain test cases (must end in _utest.c)
+SUITE_UT_SRC        :=  stream_buffer_utest.c
+
+# SUITE_SUPPORT_SRC: .c files used for testing that do not contain test cases.
+# Paths are relative to PROJECT_DIR
+SUITE_SUPPORT_SRC   :=
+
+# List the headers used by PROJECT_SRC that you would like to mock
+MOCK_FILES_FP      :=  $(KERNEL_DIR)/include/task.h
+MOCK_FILES_FP      +=  $(UT_ROOT_DIR)/config/fake_assert.h
+MOCK_FILES_FP      +=  $(UT_ROOT_DIR)/config/fake_port.h
+
+# List any addiitonal flags needed by the preprocessor
+CPPFLAGS            +=  -DportUSING_MPU_WRAPPERS=0
+
+# List any addiitonal flags needed by the compiler
+CFLAGS              +=
+
+# Try not to edit beyond this line unless necessary.
+
+# Project is determined based on path: $(UT_ROOT_DIR)/$(PROJECT)
+PROJECT         :=  $(lastword $(subst /, ,$(dir $(abspath $(MAKEFILE_ABSPATH)))))
+
+export
+
+include ../testdir.mk

FreeRTOS/Test/CMock/stream_buffer/stream_buffer.yml

@@ -0,0 +1,32 @@
+:cmock:
+  :mock_prefix: mock_
+  :when_no_prototypes: :warn
+  :treat_externs: :include
+  :enforce_strict_ordering: TRUE
+  :plugins:
+    - :ignore
+    - :ignore_arg
+    - :expect_any_args
+    - :array
+    - :callback
+    - :return_thru_ptr
+  :callback_include_count: true # include a count arg when calling the callback
+  :callback_after_arg_check: false # check arguments before calling the callback
+  :treat_as:
+    uint8:    HEX8
+    uint16:   HEX16
+    uint32:   UINT32
+    int8:     INT8
+    bool:     UINT8
+  :includes:        # This will add these includes to each mock.
+    - <stdbool.h>
+    - "FreeRTOS.h"
+  :treat_externs: :exclude  # Now the extern-ed functions will be mocked.
+  :weak: __attribute__((weak))
+  :verbosity: 3
+  :attributes:
+    - PRIVILEGED_FUNCTION
+  :strippables:
+    - PRIVILEGED_FUNCTION
+    - portDONT_DISCARD
+  :treat_externs: :include