FreeRTOS-Labs/Demo/FreeRTOS_IoT_Libraries/utilities/task_pool/DemoTasks/SimpleTaskPoolExamples.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
  * FreeRTOS Kernel V10.3.0
  * 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.
  *
  * http://www.FreeRTOS.org
  * http://aws.amazon.com/freertos
  *
  * 1 tab == 4 spaces!
  */


 /* Kernel includes. */
 #include "FreeRTOS.h"
 #include "task.h"

 /* Standard includes. */
 #include <stdio.h>

 /* IoT SDK includes. */
 #include "iot_taskpool_freertos.h"

 /* Demo includes. */
 #include "demo_config.h"

 /* The priority at which that tasks in the task pool (the worker tasks) get
 created. */
 #define tpTASK_POOL_WORKER_PRIORITY		1

 /*
  * Prototypes for the functions that demonstrate the task pool API.
  * See the implementation of the prvTaskPoolDemoTask() function within this file
  * for a description of the individual functions.  A configASSERT() is hit if
  * any of the demos encounter any unexpected behavior.
  */
 static void prvExample_BasicSingleJob( void );
 static void prvExample_DeferredJobAndCancellingJobs( void );

 /*
  * Prototypes of the callback functions used in the examples.  The callback
  * simply sends a signal (in the form of a direct task notification) to the
  * prvTaskPoolDemoTask() task to let the task know that the callback execute.
  * The handle of the prvTaskPoolDemoTask() task is not accessed directly, but
  * instead passed into the task pool job as the job's context.
  */
 static void prvSimpleTaskNotifyCallback( IotTaskPool_t pTaskPool, IotTaskPoolJob_t pJob, void *pUserContext );

 /*
  * The task used to demonstrate the task pool API.  This task just loops through
  * each demo in turn.
  */
 static void prvTaskPoolDemoTask( void *pvParameters );

 /*-----------------------------------------------------------*/

 /* Parameters used to create the system task pool - see TBD for more information
  * as the task pool used in this example is a slimmed down version of the full
  * library - the slimmed down version being intended specifically for FreeRTOS
  * kernel use cases. */
 static const IotTaskPoolInfo_t xTaskPoolParameters = {
 														/* minThreads:
 														 * Minimum number of threads in a task pool.
 														 * Note the slimmed down version of the task
 														 * pool used by this library does not auto-scale
 														 * the number of tasks in the pool so in this
 														 * case this sets the number of tasks in the
 														 * pool. */
 														IOT_TASKPOOL_NUMBER_OF_WORKERS,
 														/* maxThreads:
 														 * Maximum number of threads in a task pool.
 														 * Note the slimmed down version of the task
 														 * pool used by this library does not auto-scale
 														 * the number of tasks in the pool so in this
 														 * case this parameter must match minThreads. */
 														IOT_TASKPOOL_NUMBER_OF_WORKERS,
 														/* Stack size for every task pool thread - in
 														 * bytes, hence multiplying by the number of bytes
 														 * in a word as configMINIMAL_STACK_SIZE is
 														 * specified in words. */
 														configMINIMAL_STACK_SIZE * sizeof( portSTACK_TYPE ),
 														/* Priority for every task pool thread. */
 														tpTASK_POOL_WORKER_PRIORITY,
 													 };

 /*-----------------------------------------------------------*/

 void vStartSimpleTaskPoolDemo( void )
 {
 	/* This example uses a single application task, which in turn is used to
 	 * create and send jobs to task pool tasks. */
 	xTaskCreate( prvTaskPoolDemoTask,		/* Function that implements the task. */
 				 "PoolDemo",				/* Text name for the task - only used for debugging. */
 				 democonfigDEMO_STACKSIZE,	/* Size of stack (in words, not bytes) to allocate for the task. */
 				 NULL,						/* Task parameter - not used in this case. */
 				 tskIDLE_PRIORITY,			/* Task priority, must be between 0 and configMAX_PRIORITIES - 1. */
 				 NULL );					/* Used to pass out a handle to the created task - not used in this case. */
 }
 /*-----------------------------------------------------------*/

 static void prvTaskPoolDemoTask( void *pvParameters )
 {
 IotTaskPoolError_t xResult;
 uint32_t ulLoops = 0;

 	/* Remove compiler warnings about unused parameters. */
 	( void ) pvParameters;

 	configPRINTF( ( "---------STARTING DEMO---------\r\n" ) );

 	/* The task pool must be created before it can be used.  The system task
 	 * pool is the task pool managed by the task pool library itself - the storage
 	 * used by the task pool is provided by the library. */
 	xResult = IotTaskPool_CreateSystemTaskPool( &xTaskPoolParameters );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

 	for( ;; )
 	{
 		/* Demonstrate the most basic use case where a non persistent job is
 		 * created and scheduled to run immediately.  The task pool worker tasks
 		 * (in which the job callback function executes) have a priority above the
 		 * priority of this task so the job's callback executes as soon as it is
 		 * scheduled. */
 		prvExample_BasicSingleJob();

 		/* Demonstrate a job being scheduled to run at some time in the
 		 * future, and how a job scheduled to run in the future can be canceled
 		 * if it has not yet started executing.  */
 		prvExample_DeferredJobAndCancellingJobs();

 		ulLoops++;
 		if( ( ulLoops % 10UL ) == 0 )
 		{
 			configPRINTF( ( "prvTaskPoolDemoTask() performed %u iterations successfully.\r\n", ulLoops ) );
 			configPRINTF( ( "Demo completed successfully.\r\n" ) );
 			fflush( stdout );
 		}
 	}
 }
 /*-----------------------------------------------------------*/

 static void prvSimpleTaskNotifyCallback( IotTaskPool_t pTaskPool, IotTaskPoolJob_t pJob, void *pUserContext )
 {
 /* The jobs context is the handle of the task to which a notification should
  * be sent. */
 TaskHandle_t xTaskToNotify = ( TaskHandle_t ) pUserContext;

 	/* Remove warnings about unused parameters. */
 	( void ) pTaskPool;
 	( void ) pJob;

 	/* Notify the task that created this job. */
 	xTaskNotifyGive( xTaskToNotify );
 }
 /*-----------------------------------------------------------*/

 static void prvExample_BasicSingleJob( void )
 {
 IotTaskPoolJobStorage_t xJobStorage;
 IotTaskPoolJob_t xJob;
 IotTaskPoolError_t xResult;
 uint32_t ulReturn;
 const uint32_t ulNoFlags = 0UL;
 const TickType_t xNoDelay = ( TickType_t ) 0;
 size_t xFreeHeapBeforeCreatingJob = xPortGetFreeHeapSize();
 IotTaskPoolJobStatus_t xJobStatus;

 	/* Direct to task notifications are used to communicate between worker tasks
 	and this task.  Don't expect any notifications to be pending before commencing. */
 	configASSERT( ulTaskNotifyTake( pdTRUE, xNoDelay ) == 0 );

 	/* Create and schedule a job using the handle of this task as the job's
 	 * context and the function that sends a notification to the task handle as
 	 * the job's callback function.  This is not a recyclable job so the storage
 	 * required to hold information about the job is provided by this task - in
 	 * this case the storage is on the stack of this task so no memory is allocated
 	 * dynamically but the stack frame must remain in scope for the lifetime of
 	 * the job. */
 	xResult = IotTaskPool_CreateJob(  prvSimpleTaskNotifyCallback, /* Callback function. */
 									  ( void * ) xTaskGetCurrentTaskHandle(), /* Job context. */
 									  &xJobStorage,
 									  &xJob );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

 	/* The job has been created but not scheduled so is now ready. */
 	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
 	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_READY );

 	/* This is not a persistent (recyclable) job and its storage is on the
 	 * stack of this function, so the amount of heap space available should not
 	 * have changed since entering this function. */
 	configASSERT( xFreeHeapBeforeCreatingJob == xPortGetFreeHeapSize() );

 	/* In the full task pool implementation the first parameter is used to
 	 * pass the handle of the task pool to schedule.  The lean task pool
 	 * implementation used in this demo only supports a single task pool, which
 	 * is created internally within the library, so the first parameter is NULL. */
 	xResult = IotTaskPool_Schedule( NULL, xJob, ulNoFlags );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

 	/* Look for the notification coming from the job's callback function.  The
 	 * priority of the task pool worker task that executes the callback is higher
 	 * than the priority of this task so a block time is not needed - the task pool
 	 * worker task preempts this task and sends the notification (from the job's
 	 * callback) as soon as the job is scheduled. */
 	ulReturn = ulTaskNotifyTake( pdTRUE, xNoDelay );
 	configASSERT( ulReturn );

 	/* The job's callback has executed so the job has now completed. */
 	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
 	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_COMPLETED );
 }
 /*-----------------------------------------------------------*/

 static void prvExample_DeferredJobAndCancellingJobs( void )
 {
 IotTaskPoolJobStorage_t xJobStorage;
 IotTaskPoolJob_t xJob;
 IotTaskPoolError_t xResult;
 uint32_t ulReturn;
 const uint32_t ulShortDelay_ms = 100UL;
 const TickType_t xNoDelay = ( TickType_t ) 0, xAllowableMargin = ( TickType_t ) 5; /* Large margin for Windows port, which is not real time. */
 TickType_t xTimeBefore, xElapsedTime, xShortDelay_ticks;
 size_t xFreeHeapBeforeCreatingJob = xPortGetFreeHeapSize();
 IotTaskPoolJobStatus_t xJobStatus;

 	/* Don't expect any notifications to be pending yet. */
 	configASSERT( ulTaskNotifyTake( pdTRUE, xNoDelay ) == 0 );

 	/* Create a job using the handle of this task as the job's context and the
 	 * function that sends a notification to the task handle as the job's callback
 	 * function.  The job is created using storage allocated on the stack of this
 	 * function - so no memory is allocated. */
 	xResult = IotTaskPool_CreateJob(  prvSimpleTaskNotifyCallback, /* Callback function. */
 									  ( void * ) xTaskGetCurrentTaskHandle(), /* Job context. */
 									  &xJobStorage,
 									  &xJob );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

 	/* The job has been created but not scheduled so is now ready. */
 	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
 	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_READY );

 	/* This is not a persistent (recyclable) job and its storage is on the
 	 * stack of this function, so the amount of heap space available should not
 	 * have changed since entering this function. */
 	configASSERT( xFreeHeapBeforeCreatingJob == xPortGetFreeHeapSize() );

 	/* Schedule the job to run its callback in ulShortDelay_ms milliseconds time.
 	 * In the full task pool implementation the first parameter is used to	pass the
 	 * handle of the task pool to schedule.  The lean task pool implementation used
 	 * in this demo only supports a single task pool, which is created internally
 	 * within the library, so the first parameter is NULL. */
 	xResult = IotTaskPool_ScheduleDeferred( NULL, xJob, ulShortDelay_ms );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

 	/* The scheduled job should not have executed yet, so don't expect any
 	 * notifications and expect the job's status to be 'deferred'. */
 	ulReturn = ulTaskNotifyTake( pdTRUE, xNoDelay );
 	configASSERT( ulReturn == 0 );
 	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
 	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_DEFERRED );

 	/* As the job has not yet been executed it can be canceled. */
 	xResult = IotTaskPool_TryCancel( NULL, xJob, &xJobStatus );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );
 	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
 	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_CANCELED );

 	/* Schedule the job again, and this time wait until its callback is
 	 * executed (the callback function sends a notification to this task) to see
 	 * that it executes at the right time. */
 	xTimeBefore = xTaskGetTickCount();
 	xResult = IotTaskPool_ScheduleDeferred( NULL, xJob, ulShortDelay_ms );
 	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

 	/* Wait twice the deferred execution time to ensure the callback is executed
 	 * before the call below times out. */
 	ulReturn = ulTaskNotifyTake( pdTRUE, pdMS_TO_TICKS( ulShortDelay_ms * 2UL ) );
 	xElapsedTime = xTaskGetTickCount() - xTimeBefore;

 	/* A single notification should have been received... */
 	configASSERT( ulReturn == 1 );

 	/* ...and the time since scheduling the job should be greater than or
 	 * equal to the deferred execution time - which is converted to ticks for
 	 * comparison. */
 	xShortDelay_ticks = pdMS_TO_TICKS( ulShortDelay_ms );
 	configASSERT( ( xElapsedTime >= xShortDelay_ticks ) && ( xElapsedTime  < ( xShortDelay_ticks + xAllowableMargin ) ) );
 }
 /*-----------------------------------------------------------*/
	/*
	* FreeRTOS Kernel V10.3.0
	* 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.
	*
	* http://www.FreeRTOS.org
	* http://aws.amazon.com/freertos
	*
	* 1 tab == 4 spaces!
	*/


	/* Kernel includes. */
	#include "FreeRTOS.h"
	#include "task.h"

	/* Standard includes. */
	#include <stdio.h>

	/* IoT SDK includes. */
	#include "iot_taskpool_freertos.h"

	/* Demo includes. */
	#include "demo_config.h"

	/* The priority at which that tasks in the task pool (the worker tasks) get
	created. */
	#define tpTASK_POOL_WORKER_PRIORITY 1

	/*
	* Prototypes for the functions that demonstrate the task pool API.
	* See the implementation of the prvTaskPoolDemoTask() function within this file
	* for a description of the individual functions. A configASSERT() is hit if
	* any of the demos encounter any unexpected behavior.
	*/
	static void prvExample_BasicSingleJob( void );
	static void prvExample_DeferredJobAndCancellingJobs( void );

	/*
	* Prototypes of the callback functions used in the examples. The callback
	* simply sends a signal (in the form of a direct task notification) to the
	* prvTaskPoolDemoTask() task to let the task know that the callback execute.
	* The handle of the prvTaskPoolDemoTask() task is not accessed directly, but
	* instead passed into the task pool job as the job's context.
	*/
	static void prvSimpleTaskNotifyCallback( IotTaskPool_t pTaskPool, IotTaskPoolJob_t pJob, void *pUserContext );

	/*
	* The task used to demonstrate the task pool API. This task just loops through
	* each demo in turn.
	*/
	static void prvTaskPoolDemoTask( void *pvParameters );

	/-----------------------------------------------------------/

	/* Parameters used to create the system task pool - see TBD for more information
	* as the task pool used in this example is a slimmed down version of the full
	* library - the slimmed down version being intended specifically for FreeRTOS
	* kernel use cases. */
	static const IotTaskPoolInfo_t xTaskPoolParameters = {
	/* minThreads:
	* Minimum number of threads in a task pool.
	* Note the slimmed down version of the task
	* pool used by this library does not auto-scale
	* the number of tasks in the pool so in this
	* case this sets the number of tasks in the
	* pool. */
	IOT_TASKPOOL_NUMBER_OF_WORKERS,
	/* maxThreads:
	* Maximum number of threads in a task pool.
	* Note the slimmed down version of the task
	* pool used by this library does not auto-scale
	* the number of tasks in the pool so in this
	* case this parameter must match minThreads. */
	IOT_TASKPOOL_NUMBER_OF_WORKERS,
	/* Stack size for every task pool thread - in
	* bytes, hence multiplying by the number of bytes
	* in a word as configMINIMAL_STACK_SIZE is
	* specified in words. */
	configMINIMAL_STACK_SIZE * sizeof( portSTACK_TYPE ),
	/* Priority for every task pool thread. */
	tpTASK_POOL_WORKER_PRIORITY,
	};

	/-----------------------------------------------------------/

	void vStartSimpleTaskPoolDemo( void )
	{
	/* This example uses a single application task, which in turn is used to
	* create and send jobs to task pool tasks. */
	xTaskCreate( prvTaskPoolDemoTask, /* Function that implements the task. */
	"PoolDemo", /* Text name for the task - only used for debugging. */
	democonfigDEMO_STACKSIZE, /* Size of stack (in words, not bytes) to allocate for the task. */
	NULL, /* Task parameter - not used in this case. */
	tskIDLE_PRIORITY, /* Task priority, must be between 0 and configMAX_PRIORITIES - 1. */
	NULL ); /* Used to pass out a handle to the created task - not used in this case. */
	}
	/-----------------------------------------------------------/

	static void prvTaskPoolDemoTask( void *pvParameters )
	{
	IotTaskPoolError_t xResult;
	uint32_t ulLoops = 0;

	/* Remove compiler warnings about unused parameters. */
	( void ) pvParameters;

	configPRINTF( ( "---------STARTING DEMO---------\r\n" ) );

	/* The task pool must be created before it can be used. The system task
	* pool is the task pool managed by the task pool library itself - the storage
	* used by the task pool is provided by the library. */
	xResult = IotTaskPool_CreateSystemTaskPool( &xTaskPoolParameters );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

	for( ;; )
	{
	/* Demonstrate the most basic use case where a non persistent job is
	* created and scheduled to run immediately. The task pool worker tasks
	* (in which the job callback function executes) have a priority above the
	* priority of this task so the job's callback executes as soon as it is
	* scheduled. */
	prvExample_BasicSingleJob();

	/* Demonstrate a job being scheduled to run at some time in the
	* future, and how a job scheduled to run in the future can be canceled
	* if it has not yet started executing. */
	prvExample_DeferredJobAndCancellingJobs();

	ulLoops++;
	if( ( ulLoops % 10UL ) == 0 )
	{
	configPRINTF( ( "prvTaskPoolDemoTask() performed %u iterations successfully.\r\n", ulLoops ) );
	configPRINTF( ( "Demo completed successfully.\r\n" ) );
	fflush( stdout );
	}
	}
	}
	/-----------------------------------------------------------/

	static void prvSimpleTaskNotifyCallback( IotTaskPool_t pTaskPool, IotTaskPoolJob_t pJob, void *pUserContext )
	{
	/* The jobs context is the handle of the task to which a notification should
	* be sent. */
	TaskHandle_t xTaskToNotify = ( TaskHandle_t ) pUserContext;

	/* Remove warnings about unused parameters. */
	( void ) pTaskPool;
	( void ) pJob;

	/* Notify the task that created this job. */
	xTaskNotifyGive( xTaskToNotify );
	}
	/-----------------------------------------------------------/

	static void prvExample_BasicSingleJob( void )
	{
	IotTaskPoolJobStorage_t xJobStorage;
	IotTaskPoolJob_t xJob;
	IotTaskPoolError_t xResult;
	uint32_t ulReturn;
	const uint32_t ulNoFlags = 0UL;
	const TickType_t xNoDelay = ( TickType_t ) 0;
	size_t xFreeHeapBeforeCreatingJob = xPortGetFreeHeapSize();
	IotTaskPoolJobStatus_t xJobStatus;

	/* Direct to task notifications are used to communicate between worker tasks
	and this task. Don't expect any notifications to be pending before commencing. */
	configASSERT( ulTaskNotifyTake( pdTRUE, xNoDelay ) == 0 );

	/* Create and schedule a job using the handle of this task as the job's
	* context and the function that sends a notification to the task handle as
	* the job's callback function. This is not a recyclable job so the storage
	* required to hold information about the job is provided by this task - in
	* this case the storage is on the stack of this task so no memory is allocated
	* dynamically but the stack frame must remain in scope for the lifetime of
	* the job. */
	xResult = IotTaskPool_CreateJob( prvSimpleTaskNotifyCallback, /* Callback function. */
	( void * ) xTaskGetCurrentTaskHandle(), /* Job context. */
	&xJobStorage,
	&xJob );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

	/* The job has been created but not scheduled so is now ready. */
	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_READY );

	/* This is not a persistent (recyclable) job and its storage is on the
	* stack of this function, so the amount of heap space available should not
	* have changed since entering this function. */
	configASSERT( xFreeHeapBeforeCreatingJob == xPortGetFreeHeapSize() );

	/* In the full task pool implementation the first parameter is used to
	* pass the handle of the task pool to schedule. The lean task pool
	* implementation used in this demo only supports a single task pool, which
	* is created internally within the library, so the first parameter is NULL. */
	xResult = IotTaskPool_Schedule( NULL, xJob, ulNoFlags );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

	/* Look for the notification coming from the job's callback function. The
	* priority of the task pool worker task that executes the callback is higher
	* than the priority of this task so a block time is not needed - the task pool
	* worker task preempts this task and sends the notification (from the job's
	* callback) as soon as the job is scheduled. */
	ulReturn = ulTaskNotifyTake( pdTRUE, xNoDelay );
	configASSERT( ulReturn );

	/* The job's callback has executed so the job has now completed. */
	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_COMPLETED );
	}
	/-----------------------------------------------------------/

	static void prvExample_DeferredJobAndCancellingJobs( void )
	{
	IotTaskPoolJobStorage_t xJobStorage;
	IotTaskPoolJob_t xJob;
	IotTaskPoolError_t xResult;
	uint32_t ulReturn;
	const uint32_t ulShortDelay_ms = 100UL;
	const TickType_t xNoDelay = ( TickType_t ) 0, xAllowableMargin = ( TickType_t ) 5; /* Large margin for Windows port, which is not real time. */
	TickType_t xTimeBefore, xElapsedTime, xShortDelay_ticks;
	size_t xFreeHeapBeforeCreatingJob = xPortGetFreeHeapSize();
	IotTaskPoolJobStatus_t xJobStatus;

	/* Don't expect any notifications to be pending yet. */
	configASSERT( ulTaskNotifyTake( pdTRUE, xNoDelay ) == 0 );

	/* Create a job using the handle of this task as the job's context and the
	* function that sends a notification to the task handle as the job's callback
	* function. The job is created using storage allocated on the stack of this
	* function - so no memory is allocated. */
	xResult = IotTaskPool_CreateJob( prvSimpleTaskNotifyCallback, /* Callback function. */
	( void * ) xTaskGetCurrentTaskHandle(), /* Job context. */
	&xJobStorage,
	&xJob );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

	/* The job has been created but not scheduled so is now ready. */
	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_READY );

	/* This is not a persistent (recyclable) job and its storage is on the
	* stack of this function, so the amount of heap space available should not
	* have changed since entering this function. */
	configASSERT( xFreeHeapBeforeCreatingJob == xPortGetFreeHeapSize() );

	/* Schedule the job to run its callback in ulShortDelay_ms milliseconds time.
	* In the full task pool implementation the first parameter is used to pass the
	* handle of the task pool to schedule. The lean task pool implementation used
	* in this demo only supports a single task pool, which is created internally
	* within the library, so the first parameter is NULL. */
	xResult = IotTaskPool_ScheduleDeferred( NULL, xJob, ulShortDelay_ms );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

	/* The scheduled job should not have executed yet, so don't expect any
	* notifications and expect the job's status to be 'deferred'. */
	ulReturn = ulTaskNotifyTake( pdTRUE, xNoDelay );
	configASSERT( ulReturn == 0 );
	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_DEFERRED );

	/* As the job has not yet been executed it can be canceled. */
	xResult = IotTaskPool_TryCancel( NULL, xJob, &xJobStatus );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );
	IotTaskPool_GetStatus( NULL, xJob, &xJobStatus );
	configASSERT( xJobStatus == IOT_TASKPOOL_STATUS_CANCELED );

	/* Schedule the job again, and this time wait until its callback is
	* executed (the callback function sends a notification to this task) to see
	* that it executes at the right time. */
	xTimeBefore = xTaskGetTickCount();
	xResult = IotTaskPool_ScheduleDeferred( NULL, xJob, ulShortDelay_ms );
	configASSERT( xResult == IOT_TASKPOOL_SUCCESS );

	/* Wait twice the deferred execution time to ensure the callback is executed
	* before the call below times out. */
	ulReturn = ulTaskNotifyTake( pdTRUE, pdMS_TO_TICKS( ulShortDelay_ms * 2UL ) );
	xElapsedTime = xTaskGetTickCount() - xTimeBefore;

	/* A single notification should have been received... */
	configASSERT( ulReturn == 1 );

	/* ...and the time since scheduling the job should be greater than or
	* equal to the deferred execution time - which is converted to ticks for
	* comparison. */
	xShortDelay_ticks = pdMS_TO_TICKS( ulShortDelay_ms );
	configASSERT( ( xElapsedTime >= xShortDelay_ticks ) && ( xElapsedTime < ( xShortDelay_ticks + xAllowableMargin ) ) );
	}
	/-----------------------------------------------------------/