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diff --git a/libraries/FreeRTOS/utility/queue.h b/libraries/FreeRTOS/utility/queue.h new file mode 100755 index 0000000..9a6c86a --- /dev/null +++ b/libraries/FreeRTOS/utility/queue.h @@ -0,0 +1,1270 @@ +/* + FreeRTOS V7.0.1 - Copyright (C) 2011 Real Time Engineers Ltd. + + + FreeRTOS supports many tools and architectures. V7.0.0 is sponsored by: + Atollic AB - Atollic provides professional embedded systems development + tools for C/C++ development, code analysis and test automation. + See http://www.atollic.com + + + *************************************************************************** + * * + * FreeRTOS tutorial books are available in pdf and paperback. * + * Complete, revised, and edited pdf reference manuals are also * + * available. * + * * + * Purchasing FreeRTOS documentation will not only help you, by * + * ensuring you get running as quickly as possible and with an * + * in-depth knowledge of how to use FreeRTOS, it will also help * + * the FreeRTOS project to continue with its mission of providing * + * professional grade, cross platform, de facto standard solutions * + * for microcontrollers - completely free of charge! * + * * + * >>> See http://www.FreeRTOS.org/Documentation for details. <<< * + * * + * Thank you for using FreeRTOS, and thank you for your support! * + * * + *************************************************************************** + + + This file is part of the FreeRTOS distribution. + + FreeRTOS is free software; you can redistribute it and/or modify it under + the terms of the GNU General Public License (version 2) as published by the + Free Software Foundation AND MODIFIED BY the FreeRTOS exception. + >>>NOTE<<< The modification to the GPL is included to allow you to + distribute a combined work that includes FreeRTOS without being obliged to + provide the source code for proprietary components outside of the FreeRTOS + kernel. FreeRTOS is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + more details. You should have received a copy of the GNU General Public + License and the FreeRTOS license exception along with FreeRTOS; if not it + can be viewed here: http://www.freertos.org/a00114.html and also obtained + by writing to Richard Barry, contact details for whom are available on the + FreeRTOS WEB site. + + 1 tab == 4 spaces! + + http://www.FreeRTOS.org - Documentation, latest information, license and + contact details. + + http://www.SafeRTOS.com - A version that is certified for use in safety + critical systems. + + http://www.OpenRTOS.com - Commercial support, development, porting, + licensing and training services. +*/ + + +#ifndef QUEUE_H +#define QUEUE_H + +#ifndef INC_FREERTOS_H + #error "#include FreeRTOS.h" must appear in source files before "#include queue.h" +#endif + +#ifdef __cplusplus +extern "C" { +#endif + + +#include "mpu_wrappers.h" + +/** + * Type by which queues are referenced. For example, a call to xQueueCreate + * returns (via a pointer parameter) an xQueueHandle variable that can then + * be used as a parameter to xQueueSend(), xQueueReceive(), etc. + */ +typedef void * xQueueHandle; + + +/* For internal use only. */ +#define queueSEND_TO_BACK ( 0 ) +#define queueSEND_TO_FRONT ( 1 ) + + +/** + * queue. h + * <pre> + xQueueHandle xQueueCreate( + unsigned portBASE_TYPE uxQueueLength, + unsigned portBASE_TYPE uxItemSize + ); + * </pre> + * + * Creates a new queue instance. This allocates the storage required by the + * new queue and returns a handle for the queue. + * + * @param uxQueueLength The maximum number of items that the queue can contain. + * + * @param uxItemSize The number of bytes each item in the queue will require. + * Items are queued by copy, not by reference, so this is the number of bytes + * that will be copied for each posted item. Each item on the queue must be + * the same size. + * + * @return If the queue is successfully create then a handle to the newly + * created queue is returned. If the queue cannot be created then 0 is + * returned. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + }; + + void vATask( void *pvParameters ) + { + xQueueHandle xQueue1, xQueue2; + + // Create a queue capable of containing 10 unsigned long values. + xQueue1 = xQueueCreate( 10, sizeof( unsigned long ) ); + if( xQueue1 == 0 ) + { + // Queue was not created and must not be used. + } + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue2 = xQueueCreate( 10, sizeof( struct AMessage * ) ); + if( xQueue2 == 0 ) + { + // Queue was not created and must not be used. + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueCreate xQueueCreate + * \ingroup QueueManagement + */ +xQueueHandle xQueueCreate( unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize ); + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueSendToToFront( + xQueueHandle xQueue, + const void * pvItemToQueue, + portTickType xTicksToWait + ); + * </pre> + * + * This is a macro that calls xQueueGenericSend(). + * + * Post an item to the front of a queue. The item is queued by copy, not by + * reference. This function must not be called from an interrupt service + * routine. See xQueueSendFromISR () for an alternative which may be used + * in an ISR. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for space to become available on the queue, should it already + * be full. The call will return immediately if this is set to 0 and the + * queue is full. The time is defined in tick periods so the constant + * portTICK_RATE_MS should be used to convert to real time if this is required. + * + * @return pdTRUE if the item was successfully posted, otherwise errQUEUE_FULL. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + unsigned long ulVar = 10UL; + + void vATask( void *pvParameters ) + { + xQueueHandle xQueue1, xQueue2; + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 unsigned long values. + xQueue1 = xQueueCreate( 10, sizeof( unsigned long ) ); + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue2 = xQueueCreate( 10, sizeof( struct AMessage * ) ); + + // ... + + if( xQueue1 != 0 ) + { + // Send an unsigned long. Wait for 10 ticks for space to become + // available if necessary. + if( xQueueSendToFront( xQueue1, ( void * ) &ulVar, ( portTickType ) 10 ) != pdPASS ) + { + // Failed to post the message, even after 10 ticks. + } + } + + if( xQueue2 != 0 ) + { + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueSendToFront( xQueue2, ( void * ) &pxMessage, ( portTickType ) 0 ); + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueSend xQueueSend + * \ingroup QueueManagement + */ +#define xQueueSendToFront( xQueue, pvItemToQueue, xTicksToWait ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_FRONT ) + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueSendToBack( + xQueueHandle xQueue, + const void * pvItemToQueue, + portTickType xTicksToWait + ); + * </pre> + * + * This is a macro that calls xQueueGenericSend(). + * + * Post an item to the back of a queue. The item is queued by copy, not by + * reference. This function must not be called from an interrupt service + * routine. See xQueueSendFromISR () for an alternative which may be used + * in an ISR. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for space to become available on the queue, should it already + * be full. The call will return immediately if this is set to 0 and the queue + * is full. The time is defined in tick periods so the constant + * portTICK_RATE_MS should be used to convert to real time if this is required. + * + * @return pdTRUE if the item was successfully posted, otherwise errQUEUE_FULL. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + unsigned long ulVar = 10UL; + + void vATask( void *pvParameters ) + { + xQueueHandle xQueue1, xQueue2; + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 unsigned long values. + xQueue1 = xQueueCreate( 10, sizeof( unsigned long ) ); + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue2 = xQueueCreate( 10, sizeof( struct AMessage * ) ); + + // ... + + if( xQueue1 != 0 ) + { + // Send an unsigned long. Wait for 10 ticks for space to become + // available if necessary. + if( xQueueSendToBack( xQueue1, ( void * ) &ulVar, ( portTickType ) 10 ) != pdPASS ) + { + // Failed to post the message, even after 10 ticks. + } + } + + if( xQueue2 != 0 ) + { + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueSendToBack( xQueue2, ( void * ) &pxMessage, ( portTickType ) 0 ); + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueSend xQueueSend + * \ingroup QueueManagement + */ +#define xQueueSendToBack( xQueue, pvItemToQueue, xTicksToWait ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_BACK ) + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueSend( + xQueueHandle xQueue, + const void * pvItemToQueue, + portTickType xTicksToWait + ); + * </pre> + * + * This is a macro that calls xQueueGenericSend(). It is included for + * backward compatibility with versions of FreeRTOS.org that did not + * include the xQueueSendToFront() and xQueueSendToBack() macros. It is + * equivalent to xQueueSendToBack(). + * + * Post an item on a queue. The item is queued by copy, not by reference. + * This function must not be called from an interrupt service routine. + * See xQueueSendFromISR () for an alternative which may be used in an ISR. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for space to become available on the queue, should it already + * be full. The call will return immediately if this is set to 0 and the + * queue is full. The time is defined in tick periods so the constant + * portTICK_RATE_MS should be used to convert to real time if this is required. + * + * @return pdTRUE if the item was successfully posted, otherwise errQUEUE_FULL. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + unsigned long ulVar = 10UL; + + void vATask( void *pvParameters ) + { + xQueueHandle xQueue1, xQueue2; + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 unsigned long values. + xQueue1 = xQueueCreate( 10, sizeof( unsigned long ) ); + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue2 = xQueueCreate( 10, sizeof( struct AMessage * ) ); + + // ... + + if( xQueue1 != 0 ) + { + // Send an unsigned long. Wait for 10 ticks for space to become + // available if necessary. + if( xQueueSend( xQueue1, ( void * ) &ulVar, ( portTickType ) 10 ) != pdPASS ) + { + // Failed to post the message, even after 10 ticks. + } + } + + if( xQueue2 != 0 ) + { + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueSend( xQueue2, ( void * ) &pxMessage, ( portTickType ) 0 ); + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueSend xQueueSend + * \ingroup QueueManagement + */ +#define xQueueSend( xQueue, pvItemToQueue, xTicksToWait ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_BACK ) + + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueGenericSend( + xQueueHandle xQueue, + const void * pvItemToQueue, + portTickType xTicksToWait + portBASE_TYPE xCopyPosition + ); + * </pre> + * + * It is preferred that the macros xQueueSend(), xQueueSendToFront() and + * xQueueSendToBack() are used in place of calling this function directly. + * + * Post an item on a queue. The item is queued by copy, not by reference. + * This function must not be called from an interrupt service routine. + * See xQueueSendFromISR () for an alternative which may be used in an ISR. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for space to become available on the queue, should it already + * be full. The call will return immediately if this is set to 0 and the + * queue is full. The time is defined in tick periods so the constant + * portTICK_RATE_MS should be used to convert to real time if this is required. + * + * @param xCopyPosition Can take the value queueSEND_TO_BACK to place the + * item at the back of the queue, or queueSEND_TO_FRONT to place the item + * at the front of the queue (for high priority messages). + * + * @return pdTRUE if the item was successfully posted, otherwise errQUEUE_FULL. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + unsigned long ulVar = 10UL; + + void vATask( void *pvParameters ) + { + xQueueHandle xQueue1, xQueue2; + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 unsigned long values. + xQueue1 = xQueueCreate( 10, sizeof( unsigned long ) ); + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue2 = xQueueCreate( 10, sizeof( struct AMessage * ) ); + + // ... + + if( xQueue1 != 0 ) + { + // Send an unsigned long. Wait for 10 ticks for space to become + // available if necessary. + if( xQueueGenericSend( xQueue1, ( void * ) &ulVar, ( portTickType ) 10, queueSEND_TO_BACK ) != pdPASS ) + { + // Failed to post the message, even after 10 ticks. + } + } + + if( xQueue2 != 0 ) + { + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueGenericSend( xQueue2, ( void * ) &pxMessage, ( portTickType ) 0, queueSEND_TO_BACK ); + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueSend xQueueSend + * \ingroup QueueManagement + */ +signed portBASE_TYPE xQueueGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition ); + +/** + * queue. h + * <pre> + portBASE_TYPE xQueuePeek( + xQueueHandle xQueue, + void *pvBuffer, + portTickType xTicksToWait + );</pre> + * + * This is a macro that calls the xQueueGenericReceive() function. + * + * Receive an item from a queue without removing the item from the queue. + * The item is received by copy so a buffer of adequate size must be + * provided. The number of bytes copied into the buffer was defined when + * the queue was created. + * + * Successfully received items remain on the queue so will be returned again + * by the next call, or a call to xQueueReceive(). + * + * This macro must not be used in an interrupt service routine. + * + * @param pxQueue The handle to the queue from which the item is to be + * received. + * + * @param pvBuffer Pointer to the buffer into which the received item will + * be copied. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for an item to receive should the queue be empty at the time + * of the call. The time is defined in tick periods so the constant + * portTICK_RATE_MS should be used to convert to real time if this is required. + * xQueuePeek() will return immediately if xTicksToWait is 0 and the queue + * is empty. + * + * @return pdTRUE if an item was successfully received from the queue, + * otherwise pdFALSE. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + xQueueHandle xQueue; + + // Task to create a queue and post a value. + void vATask( void *pvParameters ) + { + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue = xQueueCreate( 10, sizeof( struct AMessage * ) ); + if( xQueue == 0 ) + { + // Failed to create the queue. + } + + // ... + + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueSend( xQueue, ( void * ) &pxMessage, ( portTickType ) 0 ); + + // ... Rest of task code. + } + + // Task to peek the data from the queue. + void vADifferentTask( void *pvParameters ) + { + struct AMessage *pxRxedMessage; + + if( xQueue != 0 ) + { + // Peek a message on the created queue. Block for 10 ticks if a + // message is not immediately available. + if( xQueuePeek( xQueue, &( pxRxedMessage ), ( portTickType ) 10 ) ) + { + // pcRxedMessage now points to the struct AMessage variable posted + // by vATask, but the item still remains on the queue. + } + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueReceive xQueueReceive + * \ingroup QueueManagement + */ +#define xQueuePeek( xQueue, pvBuffer, xTicksToWait ) xQueueGenericReceive( ( xQueue ), ( pvBuffer ), ( xTicksToWait ), pdTRUE ) + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueReceive( + xQueueHandle xQueue, + void *pvBuffer, + portTickType xTicksToWait + );</pre> + * + * This is a macro that calls the xQueueGenericReceive() function. + * + * Receive an item from a queue. The item is received by copy so a buffer of + * adequate size must be provided. The number of bytes copied into the buffer + * was defined when the queue was created. + * + * Successfully received items are removed from the queue. + * + * This function must not be used in an interrupt service routine. See + * xQueueReceiveFromISR for an alternative that can. + * + * @param pxQueue The handle to the queue from which the item is to be + * received. + * + * @param pvBuffer Pointer to the buffer into which the received item will + * be copied. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for an item to receive should the queue be empty at the time + * of the call. xQueueReceive() will return immediately if xTicksToWait + * is zero and the queue is empty. The time is defined in tick periods so the + * constant portTICK_RATE_MS should be used to convert to real time if this is + * required. + * + * @return pdTRUE if an item was successfully received from the queue, + * otherwise pdFALSE. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + xQueueHandle xQueue; + + // Task to create a queue and post a value. + void vATask( void *pvParameters ) + { + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue = xQueueCreate( 10, sizeof( struct AMessage * ) ); + if( xQueue == 0 ) + { + // Failed to create the queue. + } + + // ... + + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueSend( xQueue, ( void * ) &pxMessage, ( portTickType ) 0 ); + + // ... Rest of task code. + } + + // Task to receive from the queue. + void vADifferentTask( void *pvParameters ) + { + struct AMessage *pxRxedMessage; + + if( xQueue != 0 ) + { + // Receive a message on the created queue. Block for 10 ticks if a + // message is not immediately available. + if( xQueueReceive( xQueue, &( pxRxedMessage ), ( portTickType ) 10 ) ) + { + // pcRxedMessage now points to the struct AMessage variable posted + // by vATask. + } + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueReceive xQueueReceive + * \ingroup QueueManagement + */ +#define xQueueReceive( xQueue, pvBuffer, xTicksToWait ) xQueueGenericReceive( ( xQueue ), ( pvBuffer ), ( xTicksToWait ), pdFALSE ) + + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueGenericReceive( + xQueueHandle xQueue, + void *pvBuffer, + portTickType xTicksToWait + portBASE_TYPE xJustPeek + );</pre> + * + * It is preferred that the macro xQueueReceive() be used rather than calling + * this function directly. + * + * Receive an item from a queue. The item is received by copy so a buffer of + * adequate size must be provided. The number of bytes copied into the buffer + * was defined when the queue was created. + * + * This function must not be used in an interrupt service routine. See + * xQueueReceiveFromISR for an alternative that can. + * + * @param pxQueue The handle to the queue from which the item is to be + * received. + * + * @param pvBuffer Pointer to the buffer into which the received item will + * be copied. + * + * @param xTicksToWait The maximum amount of time the task should block + * waiting for an item to receive should the queue be empty at the time + * of the call. The time is defined in tick periods so the constant + * portTICK_RATE_MS should be used to convert to real time if this is required. + * xQueueGenericReceive() will return immediately if the queue is empty and + * xTicksToWait is 0. + * + * @param xJustPeek When set to true, the item received from the queue is not + * actually removed from the queue - meaning a subsequent call to + * xQueueReceive() will return the same item. When set to false, the item + * being received from the queue is also removed from the queue. + * + * @return pdTRUE if an item was successfully received from the queue, + * otherwise pdFALSE. + * + * Example usage: + <pre> + struct AMessage + { + char ucMessageID; + char ucData[ 20 ]; + } xMessage; + + xQueueHandle xQueue; + + // Task to create a queue and post a value. + void vATask( void *pvParameters ) + { + struct AMessage *pxMessage; + + // Create a queue capable of containing 10 pointers to AMessage structures. + // These should be passed by pointer as they contain a lot of data. + xQueue = xQueueCreate( 10, sizeof( struct AMessage * ) ); + if( xQueue == 0 ) + { + // Failed to create the queue. + } + + // ... + + // Send a pointer to a struct AMessage object. Don't block if the + // queue is already full. + pxMessage = & xMessage; + xQueueSend( xQueue, ( void * ) &pxMessage, ( portTickType ) 0 ); + + // ... Rest of task code. + } + + // Task to receive from the queue. + void vADifferentTask( void *pvParameters ) + { + struct AMessage *pxRxedMessage; + + if( xQueue != 0 ) + { + // Receive a message on the created queue. Block for 10 ticks if a + // message is not immediately available. + if( xQueueGenericReceive( xQueue, &( pxRxedMessage ), ( portTickType ) 10 ) ) + { + // pcRxedMessage now points to the struct AMessage variable posted + // by vATask. + } + } + + // ... Rest of task code. + } + </pre> + * \defgroup xQueueReceive xQueueReceive + * \ingroup QueueManagement + */ +signed portBASE_TYPE xQueueGenericReceive( xQueueHandle xQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeek ); + +/** + * queue. h + * <pre>unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle xQueue );</pre> + * + * Return the number of messages stored in a queue. + * + * @param xQueue A handle to the queue being queried. + * + * @return The number of messages available in the queue. + * + * \page uxQueueMessagesWaiting uxQueueMessagesWaiting + * \ingroup QueueManagement + */ +unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle xQueue ); + +/** + * queue. h + * <pre>void vQueueDelete( xQueueHandle xQueue );</pre> + * + * Delete a queue - freeing all the memory allocated for storing of items + * placed on the queue. + * + * @param xQueue A handle to the queue to be deleted. + * + * \page vQueueDelete vQueueDelete + * \ingroup QueueManagement + */ +void vQueueDelete( xQueueHandle pxQueue ); + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueSendToFrontFromISR( + xQueueHandle pxQueue, + const void *pvItemToQueue, + portBASE_TYPE *pxHigherPriorityTaskWoken + ); + </pre> + * + * This is a macro that calls xQueueGenericSendFromISR(). + * + * Post an item to the front of a queue. It is safe to use this macro from + * within an interrupt service routine. + * + * Items are queued by copy not reference so it is preferable to only + * queue small items, especially when called from an ISR. In most cases + * it would be preferable to store a pointer to the item being queued. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param pxHigherPriorityTaskWoken xQueueSendToFrontFromISR() will set + * *pxHigherPriorityTaskWoken to pdTRUE if sending to the queue caused a task + * to unblock, and the unblocked task has a priority higher than the currently + * running task. If xQueueSendToFromFromISR() sets this value to pdTRUE then + * a context switch should be requested before the interrupt is exited. + * + * @return pdTRUE if the data was successfully sent to the queue, otherwise + * errQUEUE_FULL. + * + * Example usage for buffered IO (where the ISR can obtain more than one value + * per call): + <pre> + void vBufferISR( void ) + { + char cIn; + portBASE_TYPE xHigherPrioritTaskWoken; + + // We have not woken a task at the start of the ISR. + xHigherPriorityTaskWoken = pdFALSE; + + // Loop until the buffer is empty. + do + { + // Obtain a byte from the buffer. + cIn = portINPUT_BYTE( RX_REGISTER_ADDRESS ); + + // Post the byte. + xQueueSendToFrontFromISR( xRxQueue, &cIn, &xHigherPriorityTaskWoken ); + + } while( portINPUT_BYTE( BUFFER_COUNT ) ); + + // Now the buffer is empty we can switch context if necessary. + if( xHigherPriorityTaskWoken ) + { + taskYIELD (); + } + } + </pre> + * + * \defgroup xQueueSendFromISR xQueueSendFromISR + * \ingroup QueueManagement + */ +#define xQueueSendToFrontFromISR( pxQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( pxQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueSEND_TO_FRONT ) + + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueSendToBackFromISR( + xQueueHandle pxQueue, + const void *pvItemToQueue, + portBASE_TYPE *pxHigherPriorityTaskWoken + ); + </pre> + * + * This is a macro that calls xQueueGenericSendFromISR(). + * + * Post an item to the back of a queue. It is safe to use this macro from + * within an interrupt service routine. + * + * Items are queued by copy not reference so it is preferable to only + * queue small items, especially when called from an ISR. In most cases + * it would be preferable to store a pointer to the item being queued. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param pxHigherPriorityTaskWoken xQueueSendToBackFromISR() will set + * *pxHigherPriorityTaskWoken to pdTRUE if sending to the queue caused a task + * to unblock, and the unblocked task has a priority higher than the currently + * running task. If xQueueSendToBackFromISR() sets this value to pdTRUE then + * a context switch should be requested before the interrupt is exited. + * + * @return pdTRUE if the data was successfully sent to the queue, otherwise + * errQUEUE_FULL. + * + * Example usage for buffered IO (where the ISR can obtain more than one value + * per call): + <pre> + void vBufferISR( void ) + { + char cIn; + portBASE_TYPE xHigherPriorityTaskWoken; + + // We have not woken a task at the start of the ISR. + xHigherPriorityTaskWoken = pdFALSE; + + // Loop until the buffer is empty. + do + { + // Obtain a byte from the buffer. + cIn = portINPUT_BYTE( RX_REGISTER_ADDRESS ); + + // Post the byte. + xQueueSendToBackFromISR( xRxQueue, &cIn, &xHigherPriorityTaskWoken ); + + } while( portINPUT_BYTE( BUFFER_COUNT ) ); + + // Now the buffer is empty we can switch context if necessary. + if( xHigherPriorityTaskWoken ) + { + taskYIELD (); + } + } + </pre> + * + * \defgroup xQueueSendFromISR xQueueSendFromISR + * \ingroup QueueManagement + */ +#define xQueueSendToBackFromISR( pxQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( pxQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueSEND_TO_BACK ) + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueSendFromISR( + xQueueHandle pxQueue, + const void *pvItemToQueue, + portBASE_TYPE *pxHigherPriorityTaskWoken + ); + </pre> + * + * This is a macro that calls xQueueGenericSendFromISR(). It is included + * for backward compatibility with versions of FreeRTOS.org that did not + * include the xQueueSendToBackFromISR() and xQueueSendToFrontFromISR() + * macros. + * + * Post an item to the back of a queue. It is safe to use this function from + * within an interrupt service routine. + * + * Items are queued by copy not reference so it is preferable to only + * queue small items, especially when called from an ISR. In most cases + * it would be preferable to store a pointer to the item being queued. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param pxHigherPriorityTaskWoken xQueueSendFromISR() will set + * *pxHigherPriorityTaskWoken to pdTRUE if sending to the queue caused a task + * to unblock, and the unblocked task has a priority higher than the currently + * running task. If xQueueSendFromISR() sets this value to pdTRUE then + * a context switch should be requested before the interrupt is exited. + * + * @return pdTRUE if the data was successfully sent to the queue, otherwise + * errQUEUE_FULL. + * + * Example usage for buffered IO (where the ISR can obtain more than one value + * per call): + <pre> + void vBufferISR( void ) + { + char cIn; + portBASE_TYPE xHigherPriorityTaskWoken; + + // We have not woken a task at the start of the ISR. + xHigherPriorityTaskWoken = pdFALSE; + + // Loop until the buffer is empty. + do + { + // Obtain a byte from the buffer. + cIn = portINPUT_BYTE( RX_REGISTER_ADDRESS ); + + // Post the byte. + xQueueSendFromISR( xRxQueue, &cIn, &xHigherPriorityTaskWoken ); + + } while( portINPUT_BYTE( BUFFER_COUNT ) ); + + // Now the buffer is empty we can switch context if necessary. + if( xHigherPriorityTaskWoken ) + { + // Actual macro used here is port specific. + taskYIELD_FROM_ISR (); + } + } + </pre> + * + * \defgroup xQueueSendFromISR xQueueSendFromISR + * \ingroup QueueManagement + */ +#define xQueueSendFromISR( pxQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( pxQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueSEND_TO_BACK ) + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueGenericSendFromISR( + xQueueHandle pxQueue, + const void *pvItemToQueue, + portBASE_TYPE *pxHigherPriorityTaskWoken, + portBASE_TYPE xCopyPosition + ); + </pre> + * + * It is preferred that the macros xQueueSendFromISR(), + * xQueueSendToFrontFromISR() and xQueueSendToBackFromISR() be used in place + * of calling this function directly. + * + * Post an item on a queue. It is safe to use this function from within an + * interrupt service routine. + * + * Items are queued by copy not reference so it is preferable to only + * queue small items, especially when called from an ISR. In most cases + * it would be preferable to store a pointer to the item being queued. + * + * @param xQueue The handle to the queue on which the item is to be posted. + * + * @param pvItemToQueue A pointer to the item that is to be placed on the + * queue. The size of the items the queue will hold was defined when the + * queue was created, so this many bytes will be copied from pvItemToQueue + * into the queue storage area. + * + * @param pxHigherPriorityTaskWoken xQueueGenericSendFromISR() will set + * *pxHigherPriorityTaskWoken to pdTRUE if sending to the queue caused a task + * to unblock, and the unblocked task has a priority higher than the currently + * running task. If xQueueGenericSendFromISR() sets this value to pdTRUE then + * a context switch should be requested before the interrupt is exited. + * + * @param xCopyPosition Can take the value queueSEND_TO_BACK to place the + * item at the back of the queue, or queueSEND_TO_FRONT to place the item + * at the front of the queue (for high priority messages). + * + * @return pdTRUE if the data was successfully sent to the queue, otherwise + * errQUEUE_FULL. + * + * Example usage for buffered IO (where the ISR can obtain more than one value + * per call): + <pre> + void vBufferISR( void ) + { + char cIn; + portBASE_TYPE xHigherPriorityTaskWokenByPost; + + // We have not woken a task at the start of the ISR. + xHigherPriorityTaskWokenByPost = pdFALSE; + + // Loop until the buffer is empty. + do + { + // Obtain a byte from the buffer. + cIn = portINPUT_BYTE( RX_REGISTER_ADDRESS ); + + // Post each byte. + xQueueGenericSendFromISR( xRxQueue, &cIn, &xHigherPriorityTaskWokenByPost, queueSEND_TO_BACK ); + + } while( portINPUT_BYTE( BUFFER_COUNT ) ); + + // Now the buffer is empty we can switch context if necessary. Note that the + // name of the yield function required is port specific. + if( xHigherPriorityTaskWokenByPost ) + { + taskYIELD_YIELD_FROM_ISR(); + } + } + </pre> + * + * \defgroup xQueueSendFromISR xQueueSendFromISR + * \ingroup QueueManagement + */ +signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition ); + +/** + * queue. h + * <pre> + portBASE_TYPE xQueueReceiveFromISR( + xQueueHandle pxQueue, + void *pvBuffer, + portBASE_TYPE *pxTaskWoken + ); + * </pre> + * + * Receive an item from a queue. It is safe to use this function from within an + * interrupt service routine. + * + * @param pxQueue The handle to the queue from which the item is to be + * received. + * + * @param pvBuffer Pointer to the buffer into which the received item will + * be copied. + * + * @param pxTaskWoken A task may be blocked waiting for space to become + * available on the queue. If xQueueReceiveFromISR causes such a task to + * unblock *pxTaskWoken will get set to pdTRUE, otherwise *pxTaskWoken will + * remain unchanged. + * + * @return pdTRUE if an item was successfully received from the queue, + * otherwise pdFALSE. + * + * Example usage: + <pre> + + xQueueHandle xQueue; + + // Function to create a queue and post some values. + void vAFunction( void *pvParameters ) + { + char cValueToPost; + const portTickType xBlockTime = ( portTickType )0xff; + + // Create a queue capable of containing 10 characters. + xQueue = xQueueCreate( 10, sizeof( char ) ); + if( xQueue == 0 ) + { + // Failed to create the queue. + } + + // ... + + // Post some characters that will be used within an ISR. If the queue + // is full then this task will block for xBlockTime ticks. + cValueToPost = 'a'; + xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime ); + cValueToPost = 'b'; + xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime ); + + // ... keep posting characters ... this task may block when the queue + // becomes full. + + cValueToPost = 'c'; + xQueueSend( xQueue, ( void * ) &cValueToPost, xBlockTime ); + } + + // ISR that outputs all the characters received on the queue. + void vISR_Routine( void ) + { + portBASE_TYPE xTaskWokenByReceive = pdFALSE; + char cRxedChar; + + while( xQueueReceiveFromISR( xQueue, ( void * ) &cRxedChar, &xTaskWokenByReceive) ) + { + // A character was received. Output the character now. + vOutputCharacter( cRxedChar ); + + // If removing the character from the queue woke the task that was + // posting onto the queue cTaskWokenByReceive will have been set to + // pdTRUE. No matter how many times this loop iterates only one + // task will be woken. + } + + if( cTaskWokenByPost != ( char ) pdFALSE; + { + taskYIELD (); + } + } + </pre> + * \defgroup xQueueReceiveFromISR xQueueReceiveFromISR + * \ingroup QueueManagement + */ +signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxTaskWoken ); + +/* + * Utilities to query queue that are safe to use from an ISR. These utilities + * should be used only from witin an ISR, or within a critical section. + */ +signed portBASE_TYPE xQueueIsQueueEmptyFromISR( const xQueueHandle pxQueue ); +signed portBASE_TYPE xQueueIsQueueFullFromISR( const xQueueHandle pxQueue ); +unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR( const xQueueHandle pxQueue ); + + +/* + * xQueueAltGenericSend() is an alternative version of xQueueGenericSend(). + * Likewise xQueueAltGenericReceive() is an alternative version of + * xQueueGenericReceive(). + * + * The source code that implements the alternative (Alt) API is much + * simpler because it executes everything from within a critical section. + * This is the approach taken by many other RTOSes, but FreeRTOS.org has the + * preferred fully featured API too. The fully featured API has more + * complex code that takes longer to execute, but makes much less use of + * critical sections. Therefore the alternative API sacrifices interrupt + * responsiveness to gain execution speed, whereas the fully featured API + * sacrifices execution speed to ensure better interrupt responsiveness. + */ +signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition ); +signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking ); +#define xQueueAltSendToFront( xQueue, pvItemToQueue, xTicksToWait ) xQueueAltGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_FRONT ) +#define xQueueAltSendToBack( xQueue, pvItemToQueue, xTicksToWait ) xQueueAltGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_BACK ) +#define xQueueAltReceive( xQueue, pvBuffer, xTicksToWait ) xQueueAltGenericReceive( ( xQueue ), ( pvBuffer ), ( xTicksToWait ), pdFALSE ) +#define xQueueAltPeek( xQueue, pvBuffer, xTicksToWait ) xQueueAltGenericReceive( ( xQueue ), ( pvBuffer ), ( xTicksToWait ), pdTRUE ) + +/* + * The functions defined above are for passing data to and from tasks. The + * functions below are the equivalents for passing data to and from + * co-routines. + * + * These functions are called from the co-routine macro implementation and + * should not be called directly from application code. Instead use the macro + * wrappers defined within croutine.h. + */ +signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken ); +signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxTaskWoken ); +signed portBASE_TYPE xQueueCRSend( xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait ); +signed portBASE_TYPE xQueueCRReceive( xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait ); + +/* + * For internal use only. Use xSemaphoreCreateMutex() or + * xSemaphoreCreateCounting() instead of calling these functions directly. + */ +xQueueHandle xQueueCreateMutex( void ); +xQueueHandle xQueueCreateCountingSemaphore( unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount ); + +/* + * For internal use only. Use xSemaphoreTakeMutexRecursive() or + * xSemaphoreGiveMutexRecursive() instead of calling these functions directly. + */ +portBASE_TYPE xQueueTakeMutexRecursive( xQueueHandle pxMutex, portTickType xBlockTime ); +portBASE_TYPE xQueueGiveMutexRecursive( xQueueHandle pxMutex ); + +/* + * The registry is provided as a means for kernel aware debuggers to + * locate queues, semaphores and mutexes. Call vQueueAddToRegistry() add + * a queue, semaphore or mutex handle to the registry if you want the handle + * to be available to a kernel aware debugger. If you are not using a kernel + * aware debugger then this function can be ignored. + * + * configQUEUE_REGISTRY_SIZE defines the maximum number of handles the + * registry can hold. configQUEUE_REGISTRY_SIZE must be greater than 0 + * within FreeRTOSConfig.h for the registry to be available. Its value + * does not effect the number of queues, semaphores and mutexes that can be + * created - just the number that the registry can hold. + * + * @param xQueue The handle of the queue being added to the registry. This + * is the handle returned by a call to xQueueCreate(). Semaphore and mutex + * handles can also be passed in here. + * + * @param pcName The name to be associated with the handle. This is the + * name that the kernel aware debugger will display. + */ +#if configQUEUE_REGISTRY_SIZE > 0U + void vQueueAddToRegistry( xQueueHandle xQueue, signed char *pcName ); +#endif + +/* Not a public API function, hence the 'Restricted' in the name. */ +void vQueueWaitForMessageRestricted( xQueueHandle pxQueue, portTickType xTicksToWait ); + + +#ifdef __cplusplus +} +#endif + +#endif /* QUEUE_H */ + |