2 FreeRTOS.org V5.1.2 - Copyright (C) 2003-2009 Richard Barry.
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4 This file is part of the FreeRTOS.org distribution.
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6 FreeRTOS.org is free software; you can redistribute it and/or modify
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7 it under the terms of the GNU General Public License as published by
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8 the Free Software Foundation; either version 2 of the License, or
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9 (at your option) any later version.
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11 FreeRTOS.org is distributed in the hope that it will be useful,
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12 but WITHOUT ANY WARRANTY; without even the implied warranty of
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13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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14 GNU General Public License for more details.
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16 You should have received a copy of the GNU General Public License
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17 along with FreeRTOS.org; if not, write to the Free Software
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18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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20 A special exception to the GPL can be applied should you wish to distribute
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21 a combined work that includes FreeRTOS.org, without being obliged to provide
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22 the source code for any proprietary components. See the licensing section
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23 of http://www.FreeRTOS.org for full details of how and when the exception
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26 ***************************************************************************
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27 ***************************************************************************
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29 * Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation *
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31 * This is a concise, step by step, 'hands on' guide that describes both *
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32 * general multitasking concepts and FreeRTOS specifics. It presents and *
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33 * explains numerous examples that are written using the FreeRTOS API. *
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34 * Full source code for all the examples is provided in an accompanying *
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37 ***************************************************************************
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38 ***************************************************************************
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40 Please ensure to read the configuration and relevant port sections of the
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41 online documentation.
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43 http://www.FreeRTOS.org - Documentation, latest information, license and
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46 http://www.SafeRTOS.com - A version that is certified for use in safety
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49 http://www.OpenRTOS.com - Commercial support, development, porting,
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50 licensing and training services.
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55 #include "FreeRTOS.h"
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57 #include "croutine.h"
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59 /*-----------------------------------------------------------
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60 * PUBLIC LIST API documented in list.h
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61 *----------------------------------------------------------*/
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63 /* Constants used with the cRxLock and cTxLock structure members. */
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64 #define queueUNLOCKED ( ( signed portBASE_TYPE ) -1 )
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65 #define queueLOCKED_UNMODIFIED ( ( signed portBASE_TYPE ) 0 )
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67 #define queueERRONEOUS_UNBLOCK ( -1 )
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69 /* For internal use only. */
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70 #define queueSEND_TO_BACK ( 0 )
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71 #define queueSEND_TO_FRONT ( 1 )
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73 /* Effectively make a union out of the xQUEUE structure. */
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74 #define pxMutexHolder pcTail
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75 #define uxQueueType pcHead
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76 #define uxRecursiveCallCount pcReadFrom
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77 #define queueQUEUE_IS_MUTEX NULL
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79 /* Semaphores do not actually store or copy data, so have an items size of
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81 #define queueSEMAPHORE_QUEUE_ITEM_LENGTH ( 0 )
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82 #define queueDONT_BLOCK ( ( portTickType ) 0 )
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83 #define queueMUTEX_GIVE_BLOCK_TIME ( ( portTickType ) 0 )
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86 * Definition of the queue used by the scheduler.
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87 * Items are queued by copy, not reference.
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89 typedef struct QueueDefinition
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91 signed portCHAR *pcHead; /*< Points to the beginning of the queue storage area. */
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92 signed portCHAR *pcTail; /*< Points to the byte at the end of the queue storage area. Once more byte is allocated than necessary to store the queue items, this is used as a marker. */
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94 signed portCHAR *pcWriteTo; /*< Points to the free next place in the storage area. */
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95 signed portCHAR *pcReadFrom; /*< Points to the last place that a queued item was read from. */
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97 xList xTasksWaitingToSend; /*< List of tasks that are blocked waiting to post onto this queue. Stored in priority order. */
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98 xList xTasksWaitingToReceive; /*< List of tasks that are blocked waiting to read from this queue. Stored in priority order. */
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100 volatile unsigned portBASE_TYPE uxMessagesWaiting;/*< The number of items currently in the queue. */
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101 unsigned portBASE_TYPE uxLength; /*< The length of the queue defined as the number of items it will hold, not the number of bytes. */
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102 unsigned portBASE_TYPE uxItemSize; /*< The size of each items that the queue will hold. */
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104 signed portBASE_TYPE xRxLock; /*< Stores the number of items received from the queue (removed from the queue) while the queue was locked. Set to queueUNLOCKED when the queue is not locked. */
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105 signed portBASE_TYPE xTxLock; /*< Stores the number of items transmitted to the queue (added to the queue) while the queue was locked. Set to queueUNLOCKED when the queue is not locked. */
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108 /*-----------------------------------------------------------*/
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111 * Inside this file xQueueHandle is a pointer to a xQUEUE structure.
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112 * To keep the definition private the API header file defines it as a
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115 typedef xQUEUE * xQueueHandle;
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118 * Prototypes for public functions are included here so we don't have to
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119 * include the API header file (as it defines xQueueHandle differently). These
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120 * functions are documented in the API header file.
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122 xQueueHandle xQueueCreate( unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize );
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123 signed portBASE_TYPE xQueueGenericSend( xQueueHandle xQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition );
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124 unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle pxQueue );
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125 void vQueueDelete( xQueueHandle xQueue );
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126 signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition );
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127 signed portBASE_TYPE xQueueGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking );
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128 signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxTaskWoken );
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129 xQueueHandle xQueueCreateMutex( void );
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130 xQueueHandle xQueueCreateCountingSemaphore( unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount );
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131 portBASE_TYPE xQueueTakeMutexRecursive( xQueueHandle xMutex, portTickType xBlockTime );
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132 portBASE_TYPE xQueueGiveMutexRecursive( xQueueHandle xMutex );
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133 signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition );
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134 signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking );
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135 signed portBASE_TYPE xQueueIsQueueEmptyFromISR( const xQueueHandle pxQueue );
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136 signed portBASE_TYPE xQueueIsQueueFullFromISR( const xQueueHandle pxQueue );
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137 unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR( const xQueueHandle pxQueue );
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140 * Co-routine queue functions differ from task queue functions. Co-routines are
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141 * an optional component.
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143 #if configUSE_CO_ROUTINES == 1
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144 signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken );
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145 signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxTaskWoken );
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146 signed portBASE_TYPE xQueueCRSend( xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait );
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147 signed portBASE_TYPE xQueueCRReceive( xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait );
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151 * The queue registry is just a means for kernel aware debuggers to locate
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152 * queue structures. It has no other purpose so is an optional component.
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154 #if configQUEUE_REGISTRY_SIZE > 0
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156 /* The type stored within the queue registry array. This allows a name
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157 to be assigned to each queue making kernel aware debugging a little
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158 more user friendly. */
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159 typedef struct QUEUE_REGISTRY_ITEM
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161 signed portCHAR *pcQueueName;
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162 xQueueHandle xHandle;
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163 } xQueueRegistryItem;
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165 /* The queue registry is simply an array of xQueueRegistryItem structures.
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166 The pcQueueName member of a structure being NULL is indicative of the
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167 array position being vacant. */
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168 xQueueRegistryItem xQueueRegistry[ configQUEUE_REGISTRY_SIZE ];
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170 /* Removes a queue from the registry by simply setting the pcQueueName
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172 static void vQueueUnregisterQueue( xQueueHandle xQueue );
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173 void vQueueAddToRegistry( xQueueHandle xQueue, signed portCHAR *pcQueueName );
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177 * Unlocks a queue locked by a call to prvLockQueue. Locking a queue does not
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178 * prevent an ISR from adding or removing items to the queue, but does prevent
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179 * an ISR from removing tasks from the queue event lists. If an ISR finds a
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180 * queue is locked it will instead increment the appropriate queue lock count
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181 * to indicate that a task may require unblocking. When the queue in unlocked
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182 * these lock counts are inspected, and the appropriate action taken.
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184 static void prvUnlockQueue( xQueueHandle pxQueue );
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187 * Uses a critical section to determine if there is any data in a queue.
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189 * @return pdTRUE if the queue contains no items, otherwise pdFALSE.
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191 static signed portBASE_TYPE prvIsQueueEmpty( const xQueueHandle pxQueue );
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194 * Uses a critical section to determine if there is any space in a queue.
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196 * @return pdTRUE if there is no space, otherwise pdFALSE;
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198 static signed portBASE_TYPE prvIsQueueFull( const xQueueHandle pxQueue );
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201 * Copies an item into the queue, either at the front of the queue or the
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202 * back of the queue.
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204 static void prvCopyDataToQueue( xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition );
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207 * Copies an item out of a queue.
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209 static void prvCopyDataFromQueue( xQUEUE * const pxQueue, const void *pvBuffer );
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210 /*-----------------------------------------------------------*/
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213 * Macro to mark a queue as locked. Locking a queue prevents an ISR from
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214 * accessing the queue event lists.
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216 #define prvLockQueue( pxQueue ) \
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218 taskENTER_CRITICAL(); \
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220 if( pxQueue->xRxLock == queueUNLOCKED ) \
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222 pxQueue->xRxLock = queueLOCKED_UNMODIFIED; \
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224 if( pxQueue->xTxLock == queueUNLOCKED ) \
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226 pxQueue->xTxLock = queueLOCKED_UNMODIFIED; \
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229 taskEXIT_CRITICAL(); \
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231 /*-----------------------------------------------------------*/
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234 /*-----------------------------------------------------------
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235 * PUBLIC QUEUE MANAGEMENT API documented in queue.h
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236 *----------------------------------------------------------*/
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238 xQueueHandle xQueueCreate( unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize )
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240 xQUEUE *pxNewQueue;
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241 size_t xQueueSizeInBytes;
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243 /* Allocate the new queue structure. */
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244 if( uxQueueLength > ( unsigned portBASE_TYPE ) 0 )
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246 pxNewQueue = ( xQUEUE * ) pvPortMalloc( sizeof( xQUEUE ) );
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247 if( pxNewQueue != NULL )
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249 /* Create the list of pointers to queue items. The queue is one byte
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250 longer than asked for to make wrap checking easier/faster. */
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251 xQueueSizeInBytes = ( size_t ) ( uxQueueLength * uxItemSize ) + ( size_t ) 1;
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253 pxNewQueue->pcHead = ( signed portCHAR * ) pvPortMalloc( xQueueSizeInBytes );
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254 if( pxNewQueue->pcHead != NULL )
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256 /* Initialise the queue members as described above where the
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257 queue type is defined. */
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258 pxNewQueue->pcTail = pxNewQueue->pcHead + ( uxQueueLength * uxItemSize );
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259 pxNewQueue->uxMessagesWaiting = 0;
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260 pxNewQueue->pcWriteTo = pxNewQueue->pcHead;
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261 pxNewQueue->pcReadFrom = pxNewQueue->pcHead + ( ( uxQueueLength - 1 ) * uxItemSize );
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262 pxNewQueue->uxLength = uxQueueLength;
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263 pxNewQueue->uxItemSize = uxItemSize;
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264 pxNewQueue->xRxLock = queueUNLOCKED;
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265 pxNewQueue->xTxLock = queueUNLOCKED;
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267 /* Likewise ensure the event queues start with the correct state. */
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268 vListInitialise( &( pxNewQueue->xTasksWaitingToSend ) );
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269 vListInitialise( &( pxNewQueue->xTasksWaitingToReceive ) );
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271 traceQUEUE_CREATE( pxNewQueue );
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277 traceQUEUE_CREATE_FAILED();
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278 vPortFree( pxNewQueue );
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283 /* Will only reach here if we could not allocate enough memory or no memory
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287 /*-----------------------------------------------------------*/
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289 #if ( configUSE_MUTEXES == 1 )
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291 xQueueHandle xQueueCreateMutex( void )
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293 xQUEUE *pxNewQueue;
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295 /* Allocate the new queue structure. */
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296 pxNewQueue = ( xQUEUE * ) pvPortMalloc( sizeof( xQUEUE ) );
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297 if( pxNewQueue != NULL )
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299 /* Information required for priority inheritance. */
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300 pxNewQueue->pxMutexHolder = NULL;
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301 pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX;
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303 /* Queues used as a mutex no data is actually copied into or out
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305 pxNewQueue->pcWriteTo = NULL;
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306 pxNewQueue->pcReadFrom = NULL;
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308 /* Each mutex has a length of 1 (like a binary semaphore) and
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309 an item size of 0 as nothing is actually copied into or out
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311 pxNewQueue->uxMessagesWaiting = 0;
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312 pxNewQueue->uxLength = 1;
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313 pxNewQueue->uxItemSize = 0;
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314 pxNewQueue->xRxLock = queueUNLOCKED;
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315 pxNewQueue->xTxLock = queueUNLOCKED;
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317 /* Ensure the event queues start with the correct state. */
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318 vListInitialise( &( pxNewQueue->xTasksWaitingToSend ) );
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319 vListInitialise( &( pxNewQueue->xTasksWaitingToReceive ) );
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321 /* Start with the semaphore in the expected state. */
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322 xQueueGenericSend( pxNewQueue, NULL, 0, queueSEND_TO_BACK );
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324 traceCREATE_MUTEX( pxNewQueue );
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328 traceCREATE_MUTEX_FAILED();
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334 #endif /* configUSE_MUTEXES */
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335 /*-----------------------------------------------------------*/
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337 #if configUSE_RECURSIVE_MUTEXES == 1
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339 portBASE_TYPE xQueueGiveMutexRecursive( xQueueHandle pxMutex )
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341 portBASE_TYPE xReturn;
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343 /* If this is the task that holds the mutex then pxMutexHolder will not
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344 change outside of this task. If this task does not hold the mutex then
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345 pxMutexHolder can never coincidentally equal the tasks handle, and as
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346 this is the only condition we are interested in it does not matter if
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347 pxMutexHolder is accessed simultaneously by another task. Therefore no
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348 mutual exclusion is required to test the pxMutexHolder variable. */
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349 if( pxMutex->pxMutexHolder == xTaskGetCurrentTaskHandle() )
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351 traceGIVE_MUTEX_RECURSIVE( pxMutex );
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353 /* uxRecursiveCallCount cannot be zero if pxMutexHolder is equal to
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354 the task handle, therefore no underflow check is required. Also,
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355 uxRecursiveCallCount is only modified by the mutex holder, and as
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356 there can only be one, no mutual exclusion is required to modify the
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357 uxRecursiveCallCount member. */
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358 ( pxMutex->uxRecursiveCallCount )--;
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360 /* Have we unwound the call count? */
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361 if( pxMutex->uxRecursiveCallCount == 0 )
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363 /* Return the mutex. This will automatically unblock any other
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364 task that might be waiting to access the mutex. */
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365 xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK );
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372 /* We cannot give the mutex because we are not the holder. */
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375 traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex );
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381 #endif /* configUSE_RECURSIVE_MUTEXES */
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382 /*-----------------------------------------------------------*/
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384 #if configUSE_RECURSIVE_MUTEXES == 1
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386 portBASE_TYPE xQueueTakeMutexRecursive( xQueueHandle pxMutex, portTickType xBlockTime )
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388 portBASE_TYPE xReturn;
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390 /* Comments regarding mutual exclusion as per those within
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391 xQueueGiveMutexRecursive(). */
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393 traceTAKE_MUTEX_RECURSIVE( pxMutex );
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395 if( pxMutex->pxMutexHolder == xTaskGetCurrentTaskHandle() )
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397 ( pxMutex->uxRecursiveCallCount )++;
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402 xReturn = xQueueGenericReceive( pxMutex, NULL, xBlockTime, pdFALSE );
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404 /* pdPASS will only be returned if we successfully obtained the mutex,
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405 we may have blocked to reach here. */
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406 if( xReturn == pdPASS )
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408 ( pxMutex->uxRecursiveCallCount )++;
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415 #endif /* configUSE_RECURSIVE_MUTEXES */
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416 /*-----------------------------------------------------------*/
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418 #if configUSE_COUNTING_SEMAPHORES == 1
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420 xQueueHandle xQueueCreateCountingSemaphore( unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount )
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422 xQueueHandle pxHandle;
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424 pxHandle = xQueueCreate( ( unsigned portBASE_TYPE ) uxCountValue, queueSEMAPHORE_QUEUE_ITEM_LENGTH );
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426 if( pxHandle != NULL )
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428 pxHandle->uxMessagesWaiting = uxInitialCount;
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430 traceCREATE_COUNTING_SEMAPHORE();
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434 traceCREATE_COUNTING_SEMAPHORE_FAILED();
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440 #endif /* configUSE_COUNTING_SEMAPHORES */
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441 /*-----------------------------------------------------------*/
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443 signed portBASE_TYPE xQueueGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition )
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445 signed portBASE_TYPE xReturn = pdTRUE;
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446 xTimeOutType xTimeOut;
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450 /* If xTicksToWait is zero then we are not going to block even
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451 if there is no room in the queue to post. */
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452 if( xTicksToWait > ( portTickType ) 0 )
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455 prvLockQueue( pxQueue );
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457 if( xReturn == pdTRUE )
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459 /* This is the first time through - we need to capture the
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460 time while the scheduler is locked to ensure we attempt to
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461 block at least once. */
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462 vTaskSetTimeOutState( &xTimeOut );
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465 if( prvIsQueueFull( pxQueue ) )
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467 /* Need to call xTaskCheckForTimeout again as time could
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468 have passed since it was last called if this is not the
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469 first time around this loop. */
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470 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
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472 traceBLOCKING_ON_QUEUE_SEND( pxQueue );
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473 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );
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475 /* Unlocking the queue means queue events can effect the
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476 event list. It is possible that interrupts occurring now
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477 remove this task from the event list again - but as the
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478 scheduler is suspended the task will go onto the pending
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479 ready last instead of the actual ready list. */
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480 prvUnlockQueue( pxQueue );
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482 /* Resuming the scheduler will move tasks from the pending
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483 ready list into the ready list - so it is feasible that this
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484 task is already in a ready list before it yields - in which
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485 case the yield will not cause a context switch unless there
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486 is also a higher priority task in the pending ready list. */
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487 if( !xTaskResumeAll() )
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494 prvUnlockQueue( pxQueue );
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495 ( void ) xTaskResumeAll();
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500 /* The queue was not full so we can just unlock the
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501 scheduler and queue again before carrying on. */
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502 prvUnlockQueue( pxQueue );
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503 ( void ) xTaskResumeAll();
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507 /* Higher priority tasks and interrupts can execute during
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508 this time and could possible refill the queue - even if we
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509 unblocked because space became available. */
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511 taskENTER_CRITICAL();
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513 /* Is there room on the queue now? To be running we must be
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514 the highest priority task wanting to access the queue. */
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515 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
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517 traceQUEUE_SEND( pxQueue );
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518 prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
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521 /* If there was a task waiting for data to arrive on the
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522 queue then unblock it now. */
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523 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
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525 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
\r
527 /* The unblocked task has a priority higher than
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528 our own so yield immediately. */
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535 /* Setting xReturn to errQUEUE_FULL will force its timeout
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536 to be re-evaluated. This is necessary in case interrupts
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537 and higher priority tasks accessed the queue between this
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538 task being unblocked and subsequently attempting to write
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540 xReturn = errQUEUE_FULL;
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543 taskEXIT_CRITICAL();
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545 if( xReturn == errQUEUE_FULL )
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547 if( xTicksToWait > ( portTickType ) 0 )
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549 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
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551 xReturn = queueERRONEOUS_UNBLOCK;
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555 traceQUEUE_SEND_FAILED( pxQueue );
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560 traceQUEUE_SEND_FAILED( pxQueue );
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564 while( xReturn == queueERRONEOUS_UNBLOCK );
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568 /*-----------------------------------------------------------*/
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570 #if configUSE_ALTERNATIVE_API == 1
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572 signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition )
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574 signed portBASE_TYPE xReturn = pdPASS;
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575 xTimeOutType xTimeOut;
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577 /* The source code that implements the alternative (Alt) API is
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578 simpler because it makes more use of critical sections. This is
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579 the approach taken by many other RTOSes, but FreeRTOS.org has the
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580 preferred fully featured API too. The fully featured API has more
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581 complex code that takes longer to execute, but makes less use of
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582 critical sections. */
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586 /* If xTicksToWait is zero then we are not going to block even
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587 if there is no room in the queue to post. */
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588 if( xTicksToWait > ( portTickType ) 0 )
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590 portENTER_CRITICAL();
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592 if( xReturn == pdPASS )
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594 /* This is the first time through - capture the time
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595 inside the critical section to ensure we attempt to
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596 block at least once. */
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597 vTaskSetTimeOutState( &xTimeOut );
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600 if( prvIsQueueFull( pxQueue ) )
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602 /* Need to call xTaskCheckForTimeout again as time could
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603 have passed since it was last called if this is not the
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604 first time around this loop. */
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605 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
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607 traceBLOCKING_ON_QUEUE_SEND( pxQueue );
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608 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );
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610 /* This will exit the critical section, then re-enter when
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611 the task next runs. */
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616 portEXIT_CRITICAL();
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619 /* Higher priority tasks and interrupts can execute during
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620 this time and could possible refill the queue - even if we
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621 unblocked because space became available. */
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623 taskENTER_CRITICAL();
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625 /* Is there room on the queue now? To be running we must be
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626 the highest priority task wanting to access the queue. */
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627 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
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629 traceQUEUE_SEND( pxQueue );
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630 prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
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633 /* If there was a task waiting for data to arrive on the
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634 queue then unblock it now. */
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635 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
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637 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
\r
639 /* The unblocked task has a priority higher than
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640 our own so yield immediately. */
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647 /* Setting xReturn to errQUEUE_FULL will force its timeout
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648 to be re-evaluated. This is necessary in case interrupts
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649 and higher priority tasks accessed the queue between this
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650 task being unblocked and subsequently attempting to write
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652 xReturn = errQUEUE_FULL;
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655 taskEXIT_CRITICAL();
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657 if( xReturn == errQUEUE_FULL )
\r
659 if( xTicksToWait > ( portTickType ) 0 )
\r
661 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
\r
663 xReturn = queueERRONEOUS_UNBLOCK;
\r
667 traceQUEUE_SEND_FAILED( pxQueue );
\r
672 traceQUEUE_SEND_FAILED( pxQueue );
\r
676 while( xReturn == queueERRONEOUS_UNBLOCK );
\r
681 #endif /* configUSE_ALTERNATIVE_API */
\r
682 /*-----------------------------------------------------------*/
\r
684 #if configUSE_ALTERNATIVE_API == 1
\r
686 signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking )
\r
688 signed portBASE_TYPE xReturn = pdTRUE;
\r
689 xTimeOutType xTimeOut;
\r
690 signed portCHAR *pcOriginalReadPosition;
\r
692 /* The source code that implements the alternative (Alt) API is
\r
693 simpler because it makes more use of critical sections. This is
\r
694 the approach taken by many other RTOSes, but FreeRTOS.org has the
\r
695 preferred fully featured API too. The fully featured API has more
\r
696 complex code that takes longer to execute, but makes less use of
\r
697 critical sections. */
\r
701 /* If there are no messages in the queue we may have to block. */
\r
702 if( xTicksToWait > ( portTickType ) 0 )
\r
704 portENTER_CRITICAL();
\r
706 if( xReturn == pdPASS )
\r
708 /* This is the first time through - capture the time
\r
709 inside the critical section to ensure we attempt to
\r
710 block at least once. */
\r
711 vTaskSetTimeOutState( &xTimeOut );
\r
714 if( prvIsQueueEmpty( pxQueue ) )
\r
716 /* Need to call xTaskCheckForTimeout again as time could
\r
717 have passed since it was last called if this is not the
\r
718 first time around this loop. */
\r
719 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
\r
721 traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );
\r
723 #if ( configUSE_MUTEXES == 1 )
\r
725 if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
\r
727 vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );
\r
732 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
\r
737 portEXIT_CRITICAL();
\r
740 taskENTER_CRITICAL();
\r
742 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
\r
744 /* Remember our read position in case we are just peeking. */
\r
745 pcOriginalReadPosition = pxQueue->pcReadFrom;
\r
747 prvCopyDataFromQueue( pxQueue, pvBuffer );
\r
749 if( xJustPeeking == pdFALSE )
\r
751 traceQUEUE_RECEIVE( pxQueue );
\r
753 /* We are actually removing data. */
\r
754 --( pxQueue->uxMessagesWaiting );
\r
756 #if ( configUSE_MUTEXES == 1 )
\r
758 if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
\r
760 /* Record the information required to implement
\r
761 priority inheritance should it become necessary. */
\r
762 pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle();
\r
767 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
\r
769 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
\r
777 traceQUEUE_PEEK( pxQueue );
\r
779 /* We are not removing the data, so reset our read
\r
781 pxQueue->pcReadFrom = pcOriginalReadPosition;
\r
783 /* The data is being left in the queue, so see if there are
\r
784 any other tasks waiting for the data. */
\r
785 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
\r
787 /* Tasks that are removed from the event list will get added to
\r
788 the pending ready list as the scheduler is still suspended. */
\r
789 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
\r
791 /* The task waiting has a higher priority that this task. */
\r
802 xReturn = errQUEUE_EMPTY;
\r
805 taskEXIT_CRITICAL();
\r
807 if( xReturn == errQUEUE_EMPTY )
\r
809 if( xTicksToWait > ( portTickType ) 0 )
\r
811 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
\r
813 xReturn = queueERRONEOUS_UNBLOCK;
\r
817 traceQUEUE_RECEIVE_FAILED( pxQueue );
\r
822 traceQUEUE_RECEIVE_FAILED( pxQueue );
\r
825 } while( xReturn == queueERRONEOUS_UNBLOCK );
\r
831 #endif /* configUSE_ALTERNATIVE_API */
\r
832 /*-----------------------------------------------------------*/
\r
834 signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition )
\r
836 signed portBASE_TYPE xReturn;
\r
837 unsigned portBASE_TYPE uxSavedInterruptStatus;
\r
839 /* Similar to xQueueGenericSend, except we don't block if there is no room
\r
840 in the queue. Also we don't directly wake a task that was blocked on a
\r
841 queue read, instead we return a flag to say whether a context switch is
\r
842 required or not (i.e. has a task with a higher priority than us been woken
\r
844 uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
\r
846 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
\r
848 traceQUEUE_SEND_FROM_ISR( pxQueue );
\r
850 prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
\r
852 /* If the queue is locked we do not alter the event list. This will
\r
853 be done when the queue is unlocked later. */
\r
854 if( pxQueue->xTxLock == queueUNLOCKED )
\r
856 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
\r
858 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
\r
860 /* The task waiting has a higher priority so record that a
\r
861 context switch is required. */
\r
862 *pxHigherPriorityTaskWoken = pdTRUE;
\r
868 /* Increment the lock count so the task that unlocks the queue
\r
869 knows that data was posted while it was locked. */
\r
870 ++( pxQueue->xTxLock );
\r
877 traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
\r
878 xReturn = errQUEUE_FULL;
\r
881 portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
\r
885 /*-----------------------------------------------------------*/
\r
887 signed portBASE_TYPE xQueueGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking )
\r
889 signed portBASE_TYPE xReturn = pdTRUE;
\r
890 xTimeOutType xTimeOut;
\r
891 signed portCHAR *pcOriginalReadPosition;
\r
895 /* If there are no messages in the queue we may have to block. */
\r
896 if( xTicksToWait > ( portTickType ) 0 )
\r
899 prvLockQueue( pxQueue );
\r
901 if( xReturn == pdTRUE )
\r
903 /* This is the first time through - we need to capture the
\r
904 time while the scheduler is locked to ensure we attempt to
\r
905 block at least once. */
\r
906 vTaskSetTimeOutState( &xTimeOut );
\r
909 if( prvIsQueueEmpty( pxQueue ) )
\r
911 /* Need to call xTaskCheckForTimeout again as time could
\r
912 have passed since it was last called if this is not the
\r
913 first time around this loop. */
\r
914 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
\r
916 traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );
\r
918 #if ( configUSE_MUTEXES == 1 )
\r
920 if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
\r
922 portENTER_CRITICAL();
\r
923 vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );
\r
924 portEXIT_CRITICAL();
\r
929 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
\r
930 prvUnlockQueue( pxQueue );
\r
931 if( !xTaskResumeAll() )
\r
938 prvUnlockQueue( pxQueue );
\r
939 ( void ) xTaskResumeAll();
\r
944 prvUnlockQueue( pxQueue );
\r
945 ( void ) xTaskResumeAll();
\r
949 taskENTER_CRITICAL();
\r
951 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
\r
953 /* Remember our read position in case we are just peeking. */
\r
954 pcOriginalReadPosition = pxQueue->pcReadFrom;
\r
956 prvCopyDataFromQueue( pxQueue, pvBuffer );
\r
958 if( xJustPeeking == pdFALSE )
\r
960 traceQUEUE_RECEIVE( pxQueue );
\r
962 /* We are actually removing data. */
\r
963 --( pxQueue->uxMessagesWaiting );
\r
965 #if ( configUSE_MUTEXES == 1 )
\r
967 if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
\r
969 /* Record the information required to implement
\r
970 priority inheritance should it become necessary. */
\r
971 pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle();
\r
976 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
\r
978 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
\r
986 traceQUEUE_PEEK( pxQueue );
\r
988 /* We are not removing the data, so reset our read
\r
990 pxQueue->pcReadFrom = pcOriginalReadPosition;
\r
992 /* The data is being left in the queue, so see if there are
\r
993 any other tasks waiting for the data. */
\r
994 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
\r
996 /* Tasks that are removed from the event list will get added to
\r
997 the pending ready list as the scheduler is still suspended. */
\r
998 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
\r
1000 /* The task waiting has a higher priority than this task. */
\r
1011 xReturn = errQUEUE_EMPTY;
\r
1014 taskEXIT_CRITICAL();
\r
1016 if( xReturn == errQUEUE_EMPTY )
\r
1018 if( xTicksToWait > ( portTickType ) 0 )
\r
1020 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
\r
1022 xReturn = queueERRONEOUS_UNBLOCK;
\r
1026 traceQUEUE_RECEIVE_FAILED( pxQueue );
\r
1031 traceQUEUE_RECEIVE_FAILED( pxQueue );
\r
1035 } while( xReturn == queueERRONEOUS_UNBLOCK );
\r
1039 /*-----------------------------------------------------------*/
\r
1041 signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxTaskWoken )
\r
1043 signed portBASE_TYPE xReturn;
\r
1044 unsigned portBASE_TYPE uxSavedInterruptStatus;
\r
1046 uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
\r
1048 /* We cannot block from an ISR, so check there is data available. */
\r
1049 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
\r
1051 traceQUEUE_RECEIVE_FROM_ISR( pxQueue );
\r
1053 prvCopyDataFromQueue( pxQueue, pvBuffer );
\r
1054 --( pxQueue->uxMessagesWaiting );
\r
1056 /* If the queue is locked we will not modify the event list. Instead
\r
1057 we update the lock count so the task that unlocks the queue will know
\r
1058 that an ISR has removed data while the queue was locked. */
\r
1059 if( pxQueue->xRxLock == queueUNLOCKED )
\r
1061 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
\r
1063 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
\r
1065 /* The task waiting has a higher priority than us so
\r
1066 force a context switch. */
\r
1067 *pxTaskWoken = pdTRUE;
\r
1073 /* Increment the lock count so the task that unlocks the queue
\r
1074 knows that data was removed while it was locked. */
\r
1075 ++( pxQueue->xRxLock );
\r
1083 traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue );
\r
1086 portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
\r
1090 /*-----------------------------------------------------------*/
\r
1092 unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle pxQueue )
\r
1094 unsigned portBASE_TYPE uxReturn;
\r
1096 taskENTER_CRITICAL();
\r
1097 uxReturn = pxQueue->uxMessagesWaiting;
\r
1098 taskEXIT_CRITICAL();
\r
1102 /*-----------------------------------------------------------*/
\r
1104 unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR( const xQueueHandle pxQueue )
\r
1106 unsigned portBASE_TYPE uxReturn;
\r
1108 uxReturn = pxQueue->uxMessagesWaiting;
\r
1112 /*-----------------------------------------------------------*/
\r
1114 void vQueueDelete( xQueueHandle pxQueue )
\r
1116 traceQUEUE_DELETE( pxQueue );
\r
1117 vQueueUnregisterQueue( pxQueue );
\r
1118 vPortFree( pxQueue->pcHead );
\r
1119 vPortFree( pxQueue );
\r
1121 /*-----------------------------------------------------------*/
\r
1123 static void prvCopyDataToQueue( xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition )
\r
1125 if( pxQueue->uxItemSize == ( unsigned portBASE_TYPE ) 0 )
\r
1127 #if ( configUSE_MUTEXES == 1 )
\r
1129 if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
\r
1131 /* The mutex is no longer being held. */
\r
1132 vTaskPriorityDisinherit( ( void * ) pxQueue->pxMutexHolder );
\r
1133 pxQueue->pxMutexHolder = NULL;
\r
1138 else if( xPosition == queueSEND_TO_BACK )
\r
1140 memcpy( ( void * ) pxQueue->pcWriteTo, pvItemToQueue, ( unsigned ) pxQueue->uxItemSize );
\r
1141 pxQueue->pcWriteTo += pxQueue->uxItemSize;
\r
1142 if( pxQueue->pcWriteTo >= pxQueue->pcTail )
\r
1144 pxQueue->pcWriteTo = pxQueue->pcHead;
\r
1149 memcpy( ( void * ) pxQueue->pcReadFrom, pvItemToQueue, ( unsigned ) pxQueue->uxItemSize );
\r
1150 pxQueue->pcReadFrom -= pxQueue->uxItemSize;
\r
1151 if( pxQueue->pcReadFrom < pxQueue->pcHead )
\r
1153 pxQueue->pcReadFrom = ( pxQueue->pcTail - pxQueue->uxItemSize );
\r
1157 ++( pxQueue->uxMessagesWaiting );
\r
1159 /*-----------------------------------------------------------*/
\r
1161 static void prvCopyDataFromQueue( xQUEUE * const pxQueue, const void *pvBuffer )
\r
1163 if( pxQueue->uxQueueType != queueQUEUE_IS_MUTEX )
\r
1165 pxQueue->pcReadFrom += pxQueue->uxItemSize;
\r
1166 if( pxQueue->pcReadFrom >= pxQueue->pcTail )
\r
1168 pxQueue->pcReadFrom = pxQueue->pcHead;
\r
1170 memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
\r
1173 /*-----------------------------------------------------------*/
\r
1175 static void prvUnlockQueue( xQueueHandle pxQueue )
\r
1177 /* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */
\r
1179 /* The lock counts contains the number of extra data items placed or
\r
1180 removed from the queue while the queue was locked. When a queue is
\r
1181 locked items can be added or removed, but the event lists cannot be
\r
1183 taskENTER_CRITICAL();
\r
1185 /* See if data was added to the queue while it was locked. */
\r
1186 while( pxQueue->xTxLock > queueLOCKED_UNMODIFIED )
\r
1188 /* Data was posted while the queue was locked. Are any tasks
\r
1189 blocked waiting for data to become available? */
\r
1190 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
\r
1192 /* Tasks that are removed from the event list will get added to
\r
1193 the pending ready list as the scheduler is still suspended. */
\r
1194 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
\r
1196 /* The task waiting has a higher priority so record that a
\r
1197 context switch is required. */
\r
1198 vTaskMissedYield();
\r
1201 --( pxQueue->xTxLock );
\r
1209 pxQueue->xTxLock = queueUNLOCKED;
\r
1211 taskEXIT_CRITICAL();
\r
1213 /* Do the same for the Rx lock. */
\r
1214 taskENTER_CRITICAL();
\r
1216 while( pxQueue->xRxLock > queueLOCKED_UNMODIFIED )
\r
1218 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
\r
1220 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
\r
1222 vTaskMissedYield();
\r
1225 --( pxQueue->xRxLock );
\r
1233 pxQueue->xRxLock = queueUNLOCKED;
\r
1235 taskEXIT_CRITICAL();
\r
1237 /*-----------------------------------------------------------*/
\r
1239 static signed portBASE_TYPE prvIsQueueEmpty( const xQueueHandle pxQueue )
\r
1241 signed portBASE_TYPE xReturn;
\r
1243 taskENTER_CRITICAL();
\r
1244 xReturn = ( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 );
\r
1245 taskEXIT_CRITICAL();
\r
1249 /*-----------------------------------------------------------*/
\r
1251 signed portBASE_TYPE xQueueIsQueueEmptyFromISR( const xQueueHandle pxQueue )
\r
1253 signed portBASE_TYPE xReturn;
\r
1255 xReturn = ( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 );
\r
1259 /*-----------------------------------------------------------*/
\r
1261 static signed portBASE_TYPE prvIsQueueFull( const xQueueHandle pxQueue )
\r
1263 signed portBASE_TYPE xReturn;
\r
1265 taskENTER_CRITICAL();
\r
1266 xReturn = ( pxQueue->uxMessagesWaiting == pxQueue->uxLength );
\r
1267 taskEXIT_CRITICAL();
\r
1271 /*-----------------------------------------------------------*/
\r
1273 signed portBASE_TYPE xQueueIsQueueFullFromISR( const xQueueHandle pxQueue )
\r
1275 signed portBASE_TYPE xReturn;
\r
1277 xReturn = ( pxQueue->uxMessagesWaiting == pxQueue->uxLength );
\r
1281 /*-----------------------------------------------------------*/
\r
1283 #if configUSE_CO_ROUTINES == 1
\r
1284 signed portBASE_TYPE xQueueCRSend( xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait )
\r
1286 signed portBASE_TYPE xReturn;
\r
1288 /* If the queue is already full we may have to block. A critical section
\r
1289 is required to prevent an interrupt removing something from the queue
\r
1290 between the check to see if the queue is full and blocking on the queue. */
\r
1291 portDISABLE_INTERRUPTS();
\r
1293 if( prvIsQueueFull( pxQueue ) )
\r
1295 /* The queue is full - do we want to block or just leave without
\r
1297 if( xTicksToWait > ( portTickType ) 0 )
\r
1299 /* As this is called from a coroutine we cannot block directly, but
\r
1300 return indicating that we need to block. */
\r
1301 vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) );
\r
1302 portENABLE_INTERRUPTS();
\r
1303 return errQUEUE_BLOCKED;
\r
1307 portENABLE_INTERRUPTS();
\r
1308 return errQUEUE_FULL;
\r
1312 portENABLE_INTERRUPTS();
\r
1316 portDISABLE_INTERRUPTS();
\r
1318 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
\r
1320 /* There is room in the queue, copy the data into the queue. */
\r
1321 prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
\r
1324 /* Were any co-routines waiting for data to become available? */
\r
1325 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
\r
1327 /* In this instance the co-routine could be placed directly
\r
1328 into the ready list as we are within a critical section.
\r
1329 Instead the same pending ready list mechanism is used as if
\r
1330 the event were caused from within an interrupt. */
\r
1331 if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
\r
1333 /* The co-routine waiting has a higher priority so record
\r
1334 that a yield might be appropriate. */
\r
1335 xReturn = errQUEUE_YIELD;
\r
1341 xReturn = errQUEUE_FULL;
\r
1344 portENABLE_INTERRUPTS();
\r
1349 /*-----------------------------------------------------------*/
\r
1351 #if configUSE_CO_ROUTINES == 1
\r
1352 signed portBASE_TYPE xQueueCRReceive( xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait )
\r
1354 signed portBASE_TYPE xReturn;
\r
1356 /* If the queue is already empty we may have to block. A critical section
\r
1357 is required to prevent an interrupt adding something to the queue
\r
1358 between the check to see if the queue is empty and blocking on the queue. */
\r
1359 portDISABLE_INTERRUPTS();
\r
1361 if( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 )
\r
1363 /* There are no messages in the queue, do we want to block or just
\r
1364 leave with nothing? */
\r
1365 if( xTicksToWait > ( portTickType ) 0 )
\r
1367 /* As this is a co-routine we cannot block directly, but return
\r
1368 indicating that we need to block. */
\r
1369 vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) );
\r
1370 portENABLE_INTERRUPTS();
\r
1371 return errQUEUE_BLOCKED;
\r
1375 portENABLE_INTERRUPTS();
\r
1376 return errQUEUE_FULL;
\r
1380 portENABLE_INTERRUPTS();
\r
1384 portDISABLE_INTERRUPTS();
\r
1386 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
\r
1388 /* Data is available from the queue. */
\r
1389 pxQueue->pcReadFrom += pxQueue->uxItemSize;
\r
1390 if( pxQueue->pcReadFrom >= pxQueue->pcTail )
\r
1392 pxQueue->pcReadFrom = pxQueue->pcHead;
\r
1394 --( pxQueue->uxMessagesWaiting );
\r
1395 memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
\r
1399 /* Were any co-routines waiting for space to become available? */
\r
1400 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
\r
1402 /* In this instance the co-routine could be placed directly
\r
1403 into the ready list as we are within a critical section.
\r
1404 Instead the same pending ready list mechanism is used as if
\r
1405 the event were caused from within an interrupt. */
\r
1406 if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
\r
1408 xReturn = errQUEUE_YIELD;
\r
1417 portENABLE_INTERRUPTS();
\r
1422 /*-----------------------------------------------------------*/
\r
1426 #if configUSE_CO_ROUTINES == 1
\r
1427 signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken )
\r
1429 /* Cannot block within an ISR so if there is no space on the queue then
\r
1430 exit without doing anything. */
\r
1431 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
\r
1433 prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
\r
1435 /* We only want to wake one co-routine per ISR, so check that a
\r
1436 co-routine has not already been woken. */
\r
1437 if( !xCoRoutinePreviouslyWoken )
\r
1439 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) )
\r
1441 if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
\r
1449 return xCoRoutinePreviouslyWoken;
\r
1452 /*-----------------------------------------------------------*/
\r
1454 #if configUSE_CO_ROUTINES == 1
\r
1455 signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxCoRoutineWoken )
\r
1457 signed portBASE_TYPE xReturn;
\r
1459 /* We cannot block from an ISR, so check there is data available. If
\r
1460 not then just leave without doing anything. */
\r
1461 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
\r
1463 /* Copy the data from the queue. */
\r
1464 pxQueue->pcReadFrom += pxQueue->uxItemSize;
\r
1465 if( pxQueue->pcReadFrom >= pxQueue->pcTail )
\r
1467 pxQueue->pcReadFrom = pxQueue->pcHead;
\r
1469 --( pxQueue->uxMessagesWaiting );
\r
1470 memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
\r
1472 if( !( *pxCoRoutineWoken ) )
\r
1474 if( !listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) )
\r
1476 if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
\r
1478 *pxCoRoutineWoken = pdTRUE;
\r
1493 /*-----------------------------------------------------------*/
\r
1495 #if configQUEUE_REGISTRY_SIZE > 0
\r
1497 void vQueueAddToRegistry( xQueueHandle xQueue, signed portCHAR *pcQueueName )
\r
1499 unsigned portBASE_TYPE ux;
\r
1501 /* See if there is an empty space in the registry. A NULL name denotes
\r
1503 for( ux = 0; ux < configQUEUE_REGISTRY_SIZE; ux++ )
\r
1505 if( xQueueRegistry[ ux ].pcQueueName == NULL )
\r
1507 /* Store the information on this queue. */
\r
1508 xQueueRegistry[ ux ].pcQueueName = pcQueueName;
\r
1509 xQueueRegistry[ ux ].xHandle = xQueue;
\r
1516 /*-----------------------------------------------------------*/
\r
1518 #if configQUEUE_REGISTRY_SIZE > 0
\r
1520 static void vQueueUnregisterQueue( xQueueHandle xQueue )
\r
1522 unsigned portBASE_TYPE ux;
\r
1524 /* See if the handle of the queue being unregistered in actually in the
\r
1526 for( ux = 0; ux < configQUEUE_REGISTRY_SIZE; ux++ )
\r
1528 if( xQueueRegistry[ ux ].xHandle == xQueue )
\r
1530 /* Set the name to NULL to show that this slot if free again. */
\r
1531 xQueueRegistry[ ux ].pcQueueName = NULL;
\r