brians | 0ab60bb | 2013-01-31 02:21:51 +0000 | [diff] [blame^] | 1 | /* |
| 2 | FreeRTOS V6.0.5 - Copyright (C) 2010 Real Time Engineers Ltd. |
| 3 | |
| 4 | *************************************************************************** |
| 5 | * * |
| 6 | * If you are: * |
| 7 | * * |
| 8 | * + New to FreeRTOS, * |
| 9 | * + Wanting to learn FreeRTOS or multitasking in general quickly * |
| 10 | * + Looking for basic training, * |
| 11 | * + Wanting to improve your FreeRTOS skills and productivity * |
| 12 | * * |
| 13 | * then take a look at the FreeRTOS eBook * |
| 14 | * * |
| 15 | * "Using the FreeRTOS Real Time Kernel - a Practical Guide" * |
| 16 | * http://www.FreeRTOS.org/Documentation * |
| 17 | * * |
| 18 | * A pdf reference manual is also available. Both are usually delivered * |
| 19 | * to your inbox within 20 minutes to two hours when purchased between 8am * |
| 20 | * and 8pm GMT (although please allow up to 24 hours in case of * |
| 21 | * exceptional circumstances). Thank you for your support! * |
| 22 | * * |
| 23 | *************************************************************************** |
| 24 | |
| 25 | This file is part of the FreeRTOS distribution. |
| 26 | |
| 27 | FreeRTOS is free software; you can redistribute it and/or modify it under |
| 28 | the terms of the GNU General Public License (version 2) as published by the |
| 29 | Free Software Foundation AND MODIFIED BY the FreeRTOS exception. |
| 30 | ***NOTE*** The exception to the GPL is included to allow you to distribute |
| 31 | a combined work that includes FreeRTOS without being obliged to provide the |
| 32 | source code for proprietary components outside of the FreeRTOS kernel. |
| 33 | FreeRTOS is distributed in the hope that it will be useful, but WITHOUT |
| 34 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 35 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 36 | more details. You should have received a copy of the GNU General Public |
| 37 | License and the FreeRTOS license exception along with FreeRTOS; if not it |
| 38 | can be viewed here: http://www.freertos.org/a00114.html and also obtained |
| 39 | by writing to Richard Barry, contact details for whom are available on the |
| 40 | FreeRTOS WEB site. |
| 41 | |
| 42 | 1 tab == 4 spaces! |
| 43 | |
| 44 | http://www.FreeRTOS.org - Documentation, latest information, license and |
| 45 | contact details. |
| 46 | |
| 47 | http://www.SafeRTOS.com - A version that is certified for use in safety |
| 48 | critical systems. |
| 49 | |
| 50 | http://www.OpenRTOS.com - Commercial support, development, porting, |
| 51 | licensing and training services. |
| 52 | */ |
| 53 | |
| 54 | #include <stdlib.h> |
| 55 | #include <string.h> |
| 56 | |
| 57 | /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining |
| 58 | all the API functions to use the MPU wrappers. That should only be done when |
| 59 | task.h is included from an application file. */ |
| 60 | #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE |
| 61 | |
| 62 | #include "FreeRTOS.h" |
| 63 | #include "task.h" |
| 64 | #include "croutine.h" |
| 65 | |
| 66 | #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE |
| 67 | |
| 68 | /*----------------------------------------------------------- |
| 69 | * PUBLIC LIST API documented in list.h |
| 70 | *----------------------------------------------------------*/ |
| 71 | |
| 72 | /* Constants used with the cRxLock and cTxLock structure members. */ |
| 73 | #define queueUNLOCKED ( ( signed portBASE_TYPE ) -1 ) |
| 74 | #define queueLOCKED_UNMODIFIED ( ( signed portBASE_TYPE ) 0 ) |
| 75 | |
| 76 | #define queueERRONEOUS_UNBLOCK ( -1 ) |
| 77 | |
| 78 | /* For internal use only. */ |
| 79 | #define queueSEND_TO_BACK ( 0 ) |
| 80 | #define queueSEND_TO_FRONT ( 1 ) |
| 81 | |
| 82 | /* Effectively make a union out of the xQUEUE structure. */ |
| 83 | #define pxMutexHolder pcTail |
| 84 | #define uxQueueType pcHead |
| 85 | #define uxRecursiveCallCount pcReadFrom |
| 86 | #define queueQUEUE_IS_MUTEX NULL |
| 87 | |
| 88 | /* Semaphores do not actually store or copy data, so have an items size of |
| 89 | zero. */ |
| 90 | #define queueSEMAPHORE_QUEUE_ITEM_LENGTH ( 0 ) |
| 91 | #define queueDONT_BLOCK ( ( portTickType ) 0 ) |
| 92 | #define queueMUTEX_GIVE_BLOCK_TIME ( ( portTickType ) 0 ) |
| 93 | |
| 94 | /* |
| 95 | * Definition of the queue used by the scheduler. |
| 96 | * Items are queued by copy, not reference. |
| 97 | */ |
| 98 | typedef struct QueueDefinition { |
| 99 | signed char *pcHead; /*< Points to the beginning of the queue storage area. */ |
| 100 | signed char *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. */ |
| 101 | |
| 102 | signed char *pcWriteTo; /*< Points to the free next place in the storage area. */ |
| 103 | signed char *pcReadFrom; /*< Points to the last place that a queued item was read from. */ |
| 104 | |
| 105 | xList xTasksWaitingToSend; /*< List of tasks that are blocked waiting to post onto this queue. Stored in priority order. */ |
| 106 | xList xTasksWaitingToReceive; /*< List of tasks that are blocked waiting to read from this queue. Stored in priority order. */ |
| 107 | |
| 108 | volatile unsigned portBASE_TYPE uxMessagesWaiting;/*< The number of items currently in the queue. */ |
| 109 | unsigned portBASE_TYPE uxLength; /*< The length of the queue defined as the number of items it will hold, not the number of bytes. */ |
| 110 | unsigned portBASE_TYPE uxItemSize; /*< The size of each items that the queue will hold. */ |
| 111 | |
| 112 | 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. */ |
| 113 | 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. */ |
| 114 | |
| 115 | } xQUEUE; |
| 116 | /*-----------------------------------------------------------*/ |
| 117 | |
| 118 | /* |
| 119 | * Inside this file xQueueHandle is a pointer to a xQUEUE structure. |
| 120 | * To keep the definition private the API header file defines it as a |
| 121 | * pointer to void. |
| 122 | */ |
| 123 | typedef xQUEUE * xQueueHandle; |
| 124 | |
| 125 | /* |
| 126 | * Prototypes for public functions are included here so we don't have to |
| 127 | * include the API header file (as it defines xQueueHandle differently). These |
| 128 | * functions are documented in the API header file. |
| 129 | */ |
| 130 | xQueueHandle xQueueCreate(unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize) PRIVILEGED_FUNCTION; |
| 131 | signed portBASE_TYPE xQueueGenericSend(xQueueHandle xQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition) PRIVILEGED_FUNCTION; |
| 132 | unsigned portBASE_TYPE uxQueueMessagesWaiting(const xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 133 | void vQueueDelete(xQueueHandle xQueue) PRIVILEGED_FUNCTION; |
| 134 | signed portBASE_TYPE xQueueGenericSendFromISR(xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition) PRIVILEGED_FUNCTION; |
| 135 | signed portBASE_TYPE xQueueGenericReceive(xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking) PRIVILEGED_FUNCTION; |
| 136 | signed portBASE_TYPE xQueueReceiveFromISR(xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxTaskWoken) PRIVILEGED_FUNCTION; |
| 137 | xQueueHandle xQueueCreateMutex(void) PRIVILEGED_FUNCTION; |
| 138 | xQueueHandle xQueueCreateCountingSemaphore(unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount) PRIVILEGED_FUNCTION; |
| 139 | portBASE_TYPE xQueueTakeMutexRecursive(xQueueHandle xMutex, portTickType xBlockTime) PRIVILEGED_FUNCTION; |
| 140 | portBASE_TYPE xQueueGiveMutexRecursive(xQueueHandle xMutex) PRIVILEGED_FUNCTION; |
| 141 | signed portBASE_TYPE xQueueAltGenericSend(xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition) PRIVILEGED_FUNCTION; |
| 142 | signed portBASE_TYPE xQueueAltGenericReceive(xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking) PRIVILEGED_FUNCTION; |
| 143 | signed portBASE_TYPE xQueueIsQueueEmptyFromISR(const xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 144 | signed portBASE_TYPE xQueueIsQueueFullFromISR(const xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 145 | unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR(const xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 146 | |
| 147 | /* |
| 148 | * Co-routine queue functions differ from task queue functions. Co-routines are |
| 149 | * an optional component. |
| 150 | */ |
| 151 | #if configUSE_CO_ROUTINES == 1 |
| 152 | signed portBASE_TYPE xQueueCRSendFromISR(xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken) PRIVILEGED_FUNCTION; |
| 153 | signed portBASE_TYPE xQueueCRReceiveFromISR(xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxTaskWoken) PRIVILEGED_FUNCTION; |
| 154 | signed portBASE_TYPE xQueueCRSend(xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait) PRIVILEGED_FUNCTION; |
| 155 | signed portBASE_TYPE xQueueCRReceive(xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait) PRIVILEGED_FUNCTION; |
| 156 | #endif |
| 157 | |
| 158 | /* |
| 159 | * The queue registry is just a means for kernel aware debuggers to locate |
| 160 | * queue structures. It has no other purpose so is an optional component. |
| 161 | */ |
| 162 | #if configQUEUE_REGISTRY_SIZE > 0 |
| 163 | |
| 164 | /* The type stored within the queue registry array. This allows a name |
| 165 | to be assigned to each queue making kernel aware debugging a little |
| 166 | more user friendly. */ |
| 167 | typedef struct QUEUE_REGISTRY_ITEM { |
| 168 | signed char *pcQueueName; |
| 169 | xQueueHandle xHandle; |
| 170 | } xQueueRegistryItem; |
| 171 | |
| 172 | /* The queue registry is simply an array of xQueueRegistryItem structures. |
| 173 | The pcQueueName member of a structure being NULL is indicative of the |
| 174 | array position being vacant. */ |
| 175 | xQueueRegistryItem xQueueRegistry[ configQUEUE_REGISTRY_SIZE ]; |
| 176 | |
| 177 | /* Removes a queue from the registry by simply setting the pcQueueName |
| 178 | member to NULL. */ |
| 179 | static void vQueueUnregisterQueue(xQueueHandle xQueue) PRIVILEGED_FUNCTION; |
| 180 | void vQueueAddToRegistry(xQueueHandle xQueue, signed char *pcQueueName) PRIVILEGED_FUNCTION; |
| 181 | #endif |
| 182 | |
| 183 | /* |
| 184 | * Unlocks a queue locked by a call to prvLockQueue. Locking a queue does not |
| 185 | * prevent an ISR from adding or removing items to the queue, but does prevent |
| 186 | * an ISR from removing tasks from the queue event lists. If an ISR finds a |
| 187 | * queue is locked it will instead increment the appropriate queue lock count |
| 188 | * to indicate that a task may require unblocking. When the queue in unlocked |
| 189 | * these lock counts are inspected, and the appropriate action taken. |
| 190 | */ |
| 191 | static void prvUnlockQueue(xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 192 | |
| 193 | /* |
| 194 | * Uses a critical section to determine if there is any data in a queue. |
| 195 | * |
| 196 | * @return pdTRUE if the queue contains no items, otherwise pdFALSE. |
| 197 | */ |
| 198 | static signed portBASE_TYPE prvIsQueueEmpty(const xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 199 | |
| 200 | /* |
| 201 | * Uses a critical section to determine if there is any space in a queue. |
| 202 | * |
| 203 | * @return pdTRUE if there is no space, otherwise pdFALSE; |
| 204 | */ |
| 205 | static signed portBASE_TYPE prvIsQueueFull(const xQueueHandle pxQueue) PRIVILEGED_FUNCTION; |
| 206 | |
| 207 | /* |
| 208 | * Copies an item into the queue, either at the front of the queue or the |
| 209 | * back of the queue. |
| 210 | */ |
| 211 | static void prvCopyDataToQueue(xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition) PRIVILEGED_FUNCTION; |
| 212 | |
| 213 | /* |
| 214 | * Copies an item out of a queue. |
| 215 | */ |
| 216 | static void prvCopyDataFromQueue(xQUEUE * const pxQueue, const void *pvBuffer) PRIVILEGED_FUNCTION; |
| 217 | /*-----------------------------------------------------------*/ |
| 218 | |
| 219 | /* |
| 220 | * Macro to mark a queue as locked. Locking a queue prevents an ISR from |
| 221 | * accessing the queue event lists. |
| 222 | */ |
| 223 | #define prvLockQueue( pxQueue ) \ |
| 224 | { \ |
| 225 | taskENTER_CRITICAL(); \ |
| 226 | { \ |
| 227 | if( pxQueue->xRxLock == queueUNLOCKED ) \ |
| 228 | { \ |
| 229 | pxQueue->xRxLock = queueLOCKED_UNMODIFIED; \ |
| 230 | } \ |
| 231 | if( pxQueue->xTxLock == queueUNLOCKED ) \ |
| 232 | { \ |
| 233 | pxQueue->xTxLock = queueLOCKED_UNMODIFIED; \ |
| 234 | } \ |
| 235 | } \ |
| 236 | taskEXIT_CRITICAL(); \ |
| 237 | } |
| 238 | /*-----------------------------------------------------------*/ |
| 239 | |
| 240 | |
| 241 | /*----------------------------------------------------------- |
| 242 | * PUBLIC QUEUE MANAGEMENT API documented in queue.h |
| 243 | *----------------------------------------------------------*/ |
| 244 | |
| 245 | xQueueHandle xQueueCreate(unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize) |
| 246 | { |
| 247 | xQUEUE *pxNewQueue; |
| 248 | size_t xQueueSizeInBytes; |
| 249 | |
| 250 | /* Allocate the new queue structure. */ |
| 251 | if (uxQueueLength > (unsigned portBASE_TYPE) 0) { |
| 252 | pxNewQueue = (xQUEUE *) pvPortMalloc(sizeof(xQUEUE)); |
| 253 | if (pxNewQueue != NULL) { |
| 254 | /* Create the list of pointers to queue items. The queue is one byte |
| 255 | longer than asked for to make wrap checking easier/faster. */ |
| 256 | xQueueSizeInBytes = (size_t)(uxQueueLength * uxItemSize) + (size_t) 1; |
| 257 | |
| 258 | pxNewQueue->pcHead = (signed char *) pvPortMalloc(xQueueSizeInBytes); |
| 259 | if (pxNewQueue->pcHead != NULL) { |
| 260 | /* Initialise the queue members as described above where the |
| 261 | queue type is defined. */ |
| 262 | pxNewQueue->pcTail = pxNewQueue->pcHead + (uxQueueLength * uxItemSize); |
| 263 | pxNewQueue->uxMessagesWaiting = 0; |
| 264 | pxNewQueue->pcWriteTo = pxNewQueue->pcHead; |
| 265 | pxNewQueue->pcReadFrom = pxNewQueue->pcHead + ((uxQueueLength - 1) * uxItemSize); |
| 266 | pxNewQueue->uxLength = uxQueueLength; |
| 267 | pxNewQueue->uxItemSize = uxItemSize; |
| 268 | pxNewQueue->xRxLock = queueUNLOCKED; |
| 269 | pxNewQueue->xTxLock = queueUNLOCKED; |
| 270 | |
| 271 | /* Likewise ensure the event queues start with the correct state. */ |
| 272 | vListInitialise(&(pxNewQueue->xTasksWaitingToSend)); |
| 273 | vListInitialise(&(pxNewQueue->xTasksWaitingToReceive)); |
| 274 | |
| 275 | traceQUEUE_CREATE(pxNewQueue); |
| 276 | return pxNewQueue; |
| 277 | } else { |
| 278 | traceQUEUE_CREATE_FAILED(); |
| 279 | vPortFree(pxNewQueue); |
| 280 | } |
| 281 | } |
| 282 | } |
| 283 | |
| 284 | /* Will only reach here if we could not allocate enough memory or no memory |
| 285 | was required. */ |
| 286 | return NULL; |
| 287 | } |
| 288 | /*-----------------------------------------------------------*/ |
| 289 | |
| 290 | #if ( configUSE_MUTEXES == 1 ) |
| 291 | |
| 292 | xQueueHandle xQueueCreateMutex(void) |
| 293 | { |
| 294 | xQUEUE *pxNewQueue; |
| 295 | |
| 296 | /* Allocate the new queue structure. */ |
| 297 | pxNewQueue = (xQUEUE *) pvPortMalloc(sizeof(xQUEUE)); |
| 298 | if (pxNewQueue != NULL) { |
| 299 | /* Information required for priority inheritance. */ |
| 300 | pxNewQueue->pxMutexHolder = NULL; |
| 301 | pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX; |
| 302 | |
| 303 | /* Queues used as a mutex no data is actually copied into or out |
| 304 | of the queue. */ |
| 305 | pxNewQueue->pcWriteTo = NULL; |
| 306 | pxNewQueue->pcReadFrom = NULL; |
| 307 | |
| 308 | /* Each mutex has a length of 1 (like a binary semaphore) and |
| 309 | an item size of 0 as nothing is actually copied into or out |
| 310 | of the mutex. */ |
| 311 | pxNewQueue->uxMessagesWaiting = 0; |
| 312 | pxNewQueue->uxLength = 1; |
| 313 | pxNewQueue->uxItemSize = 0; |
| 314 | pxNewQueue->xRxLock = queueUNLOCKED; |
| 315 | pxNewQueue->xTxLock = queueUNLOCKED; |
| 316 | |
| 317 | /* Ensure the event queues start with the correct state. */ |
| 318 | vListInitialise(&(pxNewQueue->xTasksWaitingToSend)); |
| 319 | vListInitialise(&(pxNewQueue->xTasksWaitingToReceive)); |
| 320 | |
| 321 | /* Start with the semaphore in the expected state. */ |
| 322 | xQueueGenericSend(pxNewQueue, NULL, 0, queueSEND_TO_BACK); |
| 323 | |
| 324 | traceCREATE_MUTEX(pxNewQueue); |
| 325 | } else { |
| 326 | traceCREATE_MUTEX_FAILED(); |
| 327 | } |
| 328 | |
| 329 | return pxNewQueue; |
| 330 | } |
| 331 | |
| 332 | #endif /* configUSE_MUTEXES */ |
| 333 | /*-----------------------------------------------------------*/ |
| 334 | |
| 335 | #if configUSE_RECURSIVE_MUTEXES == 1 |
| 336 | |
| 337 | portBASE_TYPE xQueueGiveMutexRecursive(xQueueHandle pxMutex) |
| 338 | { |
| 339 | portBASE_TYPE xReturn; |
| 340 | |
| 341 | /* If this is the task that holds the mutex then pxMutexHolder will not |
| 342 | change outside of this task. If this task does not hold the mutex then |
| 343 | pxMutexHolder can never coincidentally equal the tasks handle, and as |
| 344 | this is the only condition we are interested in it does not matter if |
| 345 | pxMutexHolder is accessed simultaneously by another task. Therefore no |
| 346 | mutual exclusion is required to test the pxMutexHolder variable. */ |
| 347 | if (pxMutex->pxMutexHolder == xTaskGetCurrentTaskHandle()) { |
| 348 | traceGIVE_MUTEX_RECURSIVE(pxMutex); |
| 349 | |
| 350 | /* uxRecursiveCallCount cannot be zero if pxMutexHolder is equal to |
| 351 | the task handle, therefore no underflow check is required. Also, |
| 352 | uxRecursiveCallCount is only modified by the mutex holder, and as |
| 353 | there can only be one, no mutual exclusion is required to modify the |
| 354 | uxRecursiveCallCount member. */ |
| 355 | (pxMutex->uxRecursiveCallCount)--; |
| 356 | |
| 357 | /* Have we unwound the call count? */ |
| 358 | if (pxMutex->uxRecursiveCallCount == 0) { |
| 359 | /* Return the mutex. This will automatically unblock any other |
| 360 | task that might be waiting to access the mutex. */ |
| 361 | xQueueGenericSend(pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK); |
| 362 | } |
| 363 | |
| 364 | xReturn = pdPASS; |
| 365 | } else { |
| 366 | /* We cannot give the mutex because we are not the holder. */ |
| 367 | xReturn = pdFAIL; |
| 368 | |
| 369 | traceGIVE_MUTEX_RECURSIVE_FAILED(pxMutex); |
| 370 | } |
| 371 | |
| 372 | return xReturn; |
| 373 | } |
| 374 | |
| 375 | #endif /* configUSE_RECURSIVE_MUTEXES */ |
| 376 | /*-----------------------------------------------------------*/ |
| 377 | |
| 378 | #if configUSE_RECURSIVE_MUTEXES == 1 |
| 379 | |
| 380 | portBASE_TYPE xQueueTakeMutexRecursive(xQueueHandle pxMutex, portTickType xBlockTime) |
| 381 | { |
| 382 | portBASE_TYPE xReturn; |
| 383 | |
| 384 | /* Comments regarding mutual exclusion as per those within |
| 385 | xQueueGiveMutexRecursive(). */ |
| 386 | |
| 387 | traceTAKE_MUTEX_RECURSIVE(pxMutex); |
| 388 | |
| 389 | if (pxMutex->pxMutexHolder == xTaskGetCurrentTaskHandle()) { |
| 390 | (pxMutex->uxRecursiveCallCount)++; |
| 391 | xReturn = pdPASS; |
| 392 | } else { |
| 393 | xReturn = xQueueGenericReceive(pxMutex, NULL, xBlockTime, pdFALSE); |
| 394 | |
| 395 | /* pdPASS will only be returned if we successfully obtained the mutex, |
| 396 | we may have blocked to reach here. */ |
| 397 | if (xReturn == pdPASS) { |
| 398 | (pxMutex->uxRecursiveCallCount)++; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | return xReturn; |
| 403 | } |
| 404 | |
| 405 | #endif /* configUSE_RECURSIVE_MUTEXES */ |
| 406 | /*-----------------------------------------------------------*/ |
| 407 | |
| 408 | #if configUSE_COUNTING_SEMAPHORES == 1 |
| 409 | |
| 410 | xQueueHandle xQueueCreateCountingSemaphore(unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount) |
| 411 | { |
| 412 | xQueueHandle pxHandle; |
| 413 | |
| 414 | pxHandle = xQueueCreate((unsigned portBASE_TYPE) uxCountValue, queueSEMAPHORE_QUEUE_ITEM_LENGTH); |
| 415 | |
| 416 | if (pxHandle != NULL) { |
| 417 | pxHandle->uxMessagesWaiting = uxInitialCount; |
| 418 | |
| 419 | traceCREATE_COUNTING_SEMAPHORE(); |
| 420 | } else { |
| 421 | traceCREATE_COUNTING_SEMAPHORE_FAILED(); |
| 422 | } |
| 423 | |
| 424 | return pxHandle; |
| 425 | } |
| 426 | |
| 427 | #endif /* configUSE_COUNTING_SEMAPHORES */ |
| 428 | /*-----------------------------------------------------------*/ |
| 429 | |
| 430 | signed portBASE_TYPE xQueueGenericSend(xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition) |
| 431 | { |
| 432 | signed portBASE_TYPE xEntryTimeSet = pdFALSE; |
| 433 | xTimeOutType xTimeOut; |
| 434 | |
| 435 | /* This function relaxes the coding standard somewhat to allow return |
| 436 | statements within the function itself. This is done in the interest |
| 437 | of execution time efficiency. */ |
| 438 | for (;;) { |
| 439 | taskENTER_CRITICAL(); |
| 440 | { |
| 441 | /* Is there room on the queue now? To be running we must be |
| 442 | the highest priority task wanting to access the queue. */ |
| 443 | if (pxQueue->uxMessagesWaiting < pxQueue->uxLength) { |
| 444 | traceQUEUE_SEND(pxQueue); |
| 445 | prvCopyDataToQueue(pxQueue, pvItemToQueue, xCopyPosition); |
| 446 | |
| 447 | /* If there was a task waiting for data to arrive on the |
| 448 | queue then unblock it now. */ |
| 449 | if (listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive)) == pdFALSE) { |
| 450 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) == pdTRUE) { |
| 451 | /* The unblocked task has a priority higher than |
| 452 | our own so yield immediately. Yes it is ok to do |
| 453 | this from within the critical section - the kernel |
| 454 | takes care of that. */ |
| 455 | portYIELD_WITHIN_API(); |
| 456 | } |
| 457 | } |
| 458 | |
| 459 | taskEXIT_CRITICAL(); |
| 460 | |
| 461 | /* Return to the original privilege level before exiting the |
| 462 | function. */ |
| 463 | return pdPASS; |
| 464 | } else { |
| 465 | if (xTicksToWait == (portTickType) 0) { |
| 466 | /* The queue was full and no block time is specified (or |
| 467 | the block time has expired) so leave now. */ |
| 468 | taskEXIT_CRITICAL(); |
| 469 | |
| 470 | /* Return to the original privilege level before exiting |
| 471 | the function. */ |
| 472 | traceQUEUE_SEND_FAILED(pxQueue); |
| 473 | return errQUEUE_FULL; |
| 474 | } else if (xEntryTimeSet == pdFALSE) { |
| 475 | /* The queue was full and a block time was specified so |
| 476 | configure the timeout structure. */ |
| 477 | vTaskSetTimeOutState(&xTimeOut); |
| 478 | xEntryTimeSet = pdTRUE; |
| 479 | } |
| 480 | } |
| 481 | } |
| 482 | taskEXIT_CRITICAL(); |
| 483 | |
| 484 | /* Interrupts and other tasks can send to and receive from the queue |
| 485 | now the critical section has been exited. */ |
| 486 | |
| 487 | vTaskSuspendAll(); |
| 488 | prvLockQueue(pxQueue); |
| 489 | |
| 490 | /* Update the timeout state to see if it has expired yet. */ |
| 491 | if (xTaskCheckForTimeOut(&xTimeOut, &xTicksToWait) == pdFALSE) { |
| 492 | if (prvIsQueueFull(pxQueue)) { |
| 493 | traceBLOCKING_ON_QUEUE_SEND(pxQueue); |
| 494 | vTaskPlaceOnEventList(&(pxQueue->xTasksWaitingToSend), xTicksToWait); |
| 495 | |
| 496 | /* Unlocking the queue means queue events can effect the |
| 497 | event list. It is possible that interrupts occurring now |
| 498 | remove this task from the event list again - but as the |
| 499 | scheduler is suspended the task will go onto the pending |
| 500 | ready last instead of the actual ready list. */ |
| 501 | prvUnlockQueue(pxQueue); |
| 502 | |
| 503 | /* Resuming the scheduler will move tasks from the pending |
| 504 | ready list into the ready list - so it is feasible that this |
| 505 | task is already in a ready list before it yields - in which |
| 506 | case the yield will not cause a context switch unless there |
| 507 | is also a higher priority task in the pending ready list. */ |
| 508 | if (!xTaskResumeAll()) { |
| 509 | portYIELD_WITHIN_API(); |
| 510 | } |
| 511 | } else { |
| 512 | /* Try again. */ |
| 513 | prvUnlockQueue(pxQueue); |
| 514 | (void) xTaskResumeAll(); |
| 515 | } |
| 516 | } else { |
| 517 | /* The timeout has expired. */ |
| 518 | prvUnlockQueue(pxQueue); |
| 519 | (void) xTaskResumeAll(); |
| 520 | |
| 521 | /* Return to the original privilege level before exiting the |
| 522 | function. */ |
| 523 | traceQUEUE_SEND_FAILED(pxQueue); |
| 524 | return errQUEUE_FULL; |
| 525 | } |
| 526 | } |
| 527 | } |
| 528 | /*-----------------------------------------------------------*/ |
| 529 | |
| 530 | #if configUSE_ALTERNATIVE_API == 1 |
| 531 | |
| 532 | signed portBASE_TYPE xQueueAltGenericSend(xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition) |
| 533 | { |
| 534 | signed portBASE_TYPE xEntryTimeSet = pdFALSE; |
| 535 | xTimeOutType xTimeOut; |
| 536 | |
| 537 | for (;;) { |
| 538 | taskENTER_CRITICAL(); |
| 539 | { |
| 540 | /* Is there room on the queue now? To be running we must be |
| 541 | the highest priority task wanting to access the queue. */ |
| 542 | if (pxQueue->uxMessagesWaiting < pxQueue->uxLength) { |
| 543 | traceQUEUE_SEND(pxQueue); |
| 544 | prvCopyDataToQueue(pxQueue, pvItemToQueue, xCopyPosition); |
| 545 | |
| 546 | /* If there was a task waiting for data to arrive on the |
| 547 | queue then unblock it now. */ |
| 548 | if (listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive)) == pdFALSE) { |
| 549 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) == pdTRUE) { |
| 550 | /* The unblocked task has a priority higher than |
| 551 | our own so yield immediately. */ |
| 552 | portYIELD_WITHIN_API(); |
| 553 | } |
| 554 | } |
| 555 | |
| 556 | taskEXIT_CRITICAL(); |
| 557 | return pdPASS; |
| 558 | } else { |
| 559 | if (xTicksToWait == (portTickType) 0) { |
| 560 | taskEXIT_CRITICAL(); |
| 561 | return errQUEUE_FULL; |
| 562 | } else if (xEntryTimeSet == pdFALSE) { |
| 563 | vTaskSetTimeOutState(&xTimeOut); |
| 564 | xEntryTimeSet = pdTRUE; |
| 565 | } |
| 566 | } |
| 567 | } |
| 568 | taskEXIT_CRITICAL(); |
| 569 | |
| 570 | taskENTER_CRITICAL(); |
| 571 | { |
| 572 | if (xTaskCheckForTimeOut(&xTimeOut, &xTicksToWait) == pdFALSE) { |
| 573 | if (prvIsQueueFull(pxQueue)) { |
| 574 | traceBLOCKING_ON_QUEUE_SEND(pxQueue); |
| 575 | vTaskPlaceOnEventList(&(pxQueue->xTasksWaitingToSend), xTicksToWait); |
| 576 | portYIELD_WITHIN_API(); |
| 577 | } |
| 578 | } else { |
| 579 | taskEXIT_CRITICAL(); |
| 580 | traceQUEUE_SEND_FAILED(pxQueue); |
| 581 | return errQUEUE_FULL; |
| 582 | } |
| 583 | } |
| 584 | taskEXIT_CRITICAL(); |
| 585 | } |
| 586 | } |
| 587 | |
| 588 | #endif /* configUSE_ALTERNATIVE_API */ |
| 589 | /*-----------------------------------------------------------*/ |
| 590 | |
| 591 | #if configUSE_ALTERNATIVE_API == 1 |
| 592 | |
| 593 | signed portBASE_TYPE xQueueAltGenericReceive(xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking) |
| 594 | { |
| 595 | signed portBASE_TYPE xEntryTimeSet = pdFALSE; |
| 596 | xTimeOutType xTimeOut; |
| 597 | signed char *pcOriginalReadPosition; |
| 598 | |
| 599 | for (;;) { |
| 600 | taskENTER_CRITICAL(); |
| 601 | { |
| 602 | if (pxQueue->uxMessagesWaiting > (unsigned portBASE_TYPE) 0) { |
| 603 | /* Remember our read position in case we are just peeking. */ |
| 604 | pcOriginalReadPosition = pxQueue->pcReadFrom; |
| 605 | |
| 606 | prvCopyDataFromQueue(pxQueue, pvBuffer); |
| 607 | |
| 608 | if (xJustPeeking == pdFALSE) { |
| 609 | traceQUEUE_RECEIVE(pxQueue); |
| 610 | |
| 611 | /* We are actually removing data. */ |
| 612 | --(pxQueue->uxMessagesWaiting); |
| 613 | |
| 614 | #if ( configUSE_MUTEXES == 1 ) |
| 615 | { |
| 616 | if (pxQueue->uxQueueType == queueQUEUE_IS_MUTEX) { |
| 617 | /* Record the information required to implement |
| 618 | priority inheritance should it become necessary. */ |
| 619 | pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle(); |
| 620 | } |
| 621 | } |
| 622 | #endif |
| 623 | |
| 624 | if (listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToSend)) == pdFALSE) { |
| 625 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToSend)) == pdTRUE) { |
| 626 | portYIELD_WITHIN_API(); |
| 627 | } |
| 628 | } |
| 629 | } else { |
| 630 | traceQUEUE_PEEK(pxQueue); |
| 631 | |
| 632 | /* We are not removing the data, so reset our read |
| 633 | pointer. */ |
| 634 | pxQueue->pcReadFrom = pcOriginalReadPosition; |
| 635 | |
| 636 | /* The data is being left in the queue, so see if there are |
| 637 | any other tasks waiting for the data. */ |
| 638 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive))) { |
| 639 | /* Tasks that are removed from the event list will get added to |
| 640 | the pending ready list as the scheduler is still suspended. */ |
| 641 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) != pdFALSE) { |
| 642 | /* The task waiting has a higher priority than this task. */ |
| 643 | portYIELD_WITHIN_API(); |
| 644 | } |
| 645 | } |
| 646 | |
| 647 | } |
| 648 | |
| 649 | taskEXIT_CRITICAL(); |
| 650 | return pdPASS; |
| 651 | } else { |
| 652 | if (xTicksToWait == (portTickType) 0) { |
| 653 | taskEXIT_CRITICAL(); |
| 654 | traceQUEUE_RECEIVE_FAILED(pxQueue); |
| 655 | return errQUEUE_EMPTY; |
| 656 | } else if (xEntryTimeSet == pdFALSE) { |
| 657 | vTaskSetTimeOutState(&xTimeOut); |
| 658 | xEntryTimeSet = pdTRUE; |
| 659 | } |
| 660 | } |
| 661 | } |
| 662 | taskEXIT_CRITICAL(); |
| 663 | |
| 664 | taskENTER_CRITICAL(); |
| 665 | { |
| 666 | if (xTaskCheckForTimeOut(&xTimeOut, &xTicksToWait) == pdFALSE) { |
| 667 | if (prvIsQueueEmpty(pxQueue)) { |
| 668 | traceBLOCKING_ON_QUEUE_RECEIVE(pxQueue); |
| 669 | |
| 670 | #if ( configUSE_MUTEXES == 1 ) |
| 671 | { |
| 672 | if (pxQueue->uxQueueType == queueQUEUE_IS_MUTEX) { |
| 673 | portENTER_CRITICAL(); |
| 674 | vTaskPriorityInherit((void *) pxQueue->pxMutexHolder); |
| 675 | portEXIT_CRITICAL(); |
| 676 | } |
| 677 | } |
| 678 | #endif |
| 679 | |
| 680 | vTaskPlaceOnEventList(&(pxQueue->xTasksWaitingToReceive), xTicksToWait); |
| 681 | portYIELD_WITHIN_API(); |
| 682 | } |
| 683 | } else { |
| 684 | taskEXIT_CRITICAL(); |
| 685 | traceQUEUE_RECEIVE_FAILED(pxQueue); |
| 686 | return errQUEUE_EMPTY; |
| 687 | } |
| 688 | } |
| 689 | taskEXIT_CRITICAL(); |
| 690 | } |
| 691 | } |
| 692 | |
| 693 | |
| 694 | #endif /* configUSE_ALTERNATIVE_API */ |
| 695 | /*-----------------------------------------------------------*/ |
| 696 | |
| 697 | signed portBASE_TYPE xQueueGenericSendFromISR(xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition) |
| 698 | { |
| 699 | signed portBASE_TYPE xReturn; |
| 700 | unsigned portBASE_TYPE uxSavedInterruptStatus; |
| 701 | |
| 702 | /* Similar to xQueueGenericSend, except we don't block if there is no room |
| 703 | in the queue. Also we don't directly wake a task that was blocked on a |
| 704 | queue read, instead we return a flag to say whether a context switch is |
| 705 | required or not (i.e. has a task with a higher priority than us been woken |
| 706 | by this post). */ |
| 707 | uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR(); |
| 708 | { |
| 709 | if (pxQueue->uxMessagesWaiting < pxQueue->uxLength) { |
| 710 | traceQUEUE_SEND_FROM_ISR(pxQueue); |
| 711 | |
| 712 | prvCopyDataToQueue(pxQueue, pvItemToQueue, xCopyPosition); |
| 713 | |
| 714 | /* If the queue is locked we do not alter the event list. This will |
| 715 | be done when the queue is unlocked later. */ |
| 716 | if (pxQueue->xTxLock == queueUNLOCKED) { |
| 717 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive))) { |
| 718 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) != pdFALSE) { |
| 719 | /* The task waiting has a higher priority so record that a |
| 720 | context switch is required. */ |
| 721 | *pxHigherPriorityTaskWoken = pdTRUE; |
| 722 | } |
| 723 | } |
| 724 | } else { |
| 725 | /* Increment the lock count so the task that unlocks the queue |
| 726 | knows that data was posted while it was locked. */ |
| 727 | ++(pxQueue->xTxLock); |
| 728 | } |
| 729 | |
| 730 | xReturn = pdPASS; |
| 731 | } else { |
| 732 | traceQUEUE_SEND_FROM_ISR_FAILED(pxQueue); |
| 733 | xReturn = errQUEUE_FULL; |
| 734 | } |
| 735 | } |
| 736 | portCLEAR_INTERRUPT_MASK_FROM_ISR(uxSavedInterruptStatus); |
| 737 | |
| 738 | return xReturn; |
| 739 | } |
| 740 | /*-----------------------------------------------------------*/ |
| 741 | |
| 742 | signed portBASE_TYPE xQueueGenericReceive(xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking) |
| 743 | { |
| 744 | signed portBASE_TYPE xEntryTimeSet = pdFALSE; |
| 745 | xTimeOutType xTimeOut; |
| 746 | signed char *pcOriginalReadPosition; |
| 747 | |
| 748 | /* This function relaxes the coding standard somewhat to allow return |
| 749 | statements within the function itself. This is done in the interest |
| 750 | of execution time efficiency. */ |
| 751 | |
| 752 | for (;;) { |
| 753 | taskENTER_CRITICAL(); |
| 754 | { |
| 755 | /* Is there data in the queue now? To be running we must be |
| 756 | the highest priority task wanting to access the queue. */ |
| 757 | if (pxQueue->uxMessagesWaiting > (unsigned portBASE_TYPE) 0) { |
| 758 | /* Remember our read position in case we are just peeking. */ |
| 759 | pcOriginalReadPosition = pxQueue->pcReadFrom; |
| 760 | |
| 761 | prvCopyDataFromQueue(pxQueue, pvBuffer); |
| 762 | |
| 763 | if (xJustPeeking == pdFALSE) { |
| 764 | traceQUEUE_RECEIVE(pxQueue); |
| 765 | |
| 766 | /* We are actually removing data. */ |
| 767 | --(pxQueue->uxMessagesWaiting); |
| 768 | |
| 769 | #if ( configUSE_MUTEXES == 1 ) |
| 770 | { |
| 771 | if (pxQueue->uxQueueType == queueQUEUE_IS_MUTEX) { |
| 772 | /* Record the information required to implement |
| 773 | priority inheritance should it become necessary. */ |
| 774 | pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle(); |
| 775 | } |
| 776 | } |
| 777 | #endif |
| 778 | |
| 779 | if (listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToSend)) == pdFALSE) { |
| 780 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToSend)) == pdTRUE) { |
| 781 | portYIELD_WITHIN_API(); |
| 782 | } |
| 783 | } |
| 784 | } else { |
| 785 | traceQUEUE_PEEK(pxQueue); |
| 786 | |
| 787 | /* We are not removing the data, so reset our read |
| 788 | pointer. */ |
| 789 | pxQueue->pcReadFrom = pcOriginalReadPosition; |
| 790 | |
| 791 | /* The data is being left in the queue, so see if there are |
| 792 | any other tasks waiting for the data. */ |
| 793 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive))) { |
| 794 | /* Tasks that are removed from the event list will get added to |
| 795 | the pending ready list as the scheduler is still suspended. */ |
| 796 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) != pdFALSE) { |
| 797 | /* The task waiting has a higher priority than this task. */ |
| 798 | portYIELD_WITHIN_API(); |
| 799 | } |
| 800 | } |
| 801 | |
| 802 | } |
| 803 | |
| 804 | taskEXIT_CRITICAL(); |
| 805 | return pdPASS; |
| 806 | } else { |
| 807 | if (xTicksToWait == (portTickType) 0) { |
| 808 | /* The queue was empty and no block time is specified (or |
| 809 | the block time has expired) so leave now. */ |
| 810 | taskEXIT_CRITICAL(); |
| 811 | traceQUEUE_RECEIVE_FAILED(pxQueue); |
| 812 | return errQUEUE_EMPTY; |
| 813 | } else if (xEntryTimeSet == pdFALSE) { |
| 814 | /* The queue was empty and a block time was specified so |
| 815 | configure the timeout structure. */ |
| 816 | vTaskSetTimeOutState(&xTimeOut); |
| 817 | xEntryTimeSet = pdTRUE; |
| 818 | } |
| 819 | } |
| 820 | } |
| 821 | taskEXIT_CRITICAL(); |
| 822 | |
| 823 | /* Interrupts and other tasks can send to and receive from the queue |
| 824 | now the critical section has been exited. */ |
| 825 | |
| 826 | vTaskSuspendAll(); |
| 827 | prvLockQueue(pxQueue); |
| 828 | |
| 829 | /* Update the timeout state to see if it has expired yet. */ |
| 830 | if (xTaskCheckForTimeOut(&xTimeOut, &xTicksToWait) == pdFALSE) { |
| 831 | if (prvIsQueueEmpty(pxQueue)) { |
| 832 | traceBLOCKING_ON_QUEUE_RECEIVE(pxQueue); |
| 833 | |
| 834 | #if ( configUSE_MUTEXES == 1 ) |
| 835 | { |
| 836 | if (pxQueue->uxQueueType == queueQUEUE_IS_MUTEX) { |
| 837 | portENTER_CRITICAL(); |
| 838 | { |
| 839 | vTaskPriorityInherit((void *) pxQueue->pxMutexHolder); |
| 840 | } |
| 841 | portEXIT_CRITICAL(); |
| 842 | } |
| 843 | } |
| 844 | #endif |
| 845 | |
| 846 | vTaskPlaceOnEventList(&(pxQueue->xTasksWaitingToReceive), xTicksToWait); |
| 847 | prvUnlockQueue(pxQueue); |
| 848 | if (!xTaskResumeAll()) { |
| 849 | portYIELD_WITHIN_API(); |
| 850 | } |
| 851 | } else { |
| 852 | /* Try again. */ |
| 853 | prvUnlockQueue(pxQueue); |
| 854 | (void) xTaskResumeAll(); |
| 855 | } |
| 856 | } else { |
| 857 | prvUnlockQueue(pxQueue); |
| 858 | (void) xTaskResumeAll(); |
| 859 | traceQUEUE_RECEIVE_FAILED(pxQueue); |
| 860 | return errQUEUE_EMPTY; |
| 861 | } |
| 862 | } |
| 863 | } |
| 864 | /*-----------------------------------------------------------*/ |
| 865 | |
| 866 | signed portBASE_TYPE xQueueReceiveFromISR(xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxTaskWoken) |
| 867 | { |
| 868 | signed portBASE_TYPE xReturn; |
| 869 | unsigned portBASE_TYPE uxSavedInterruptStatus; |
| 870 | |
| 871 | uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR(); |
| 872 | { |
| 873 | /* We cannot block from an ISR, so check there is data available. */ |
| 874 | if (pxQueue->uxMessagesWaiting > (unsigned portBASE_TYPE) 0) { |
| 875 | traceQUEUE_RECEIVE_FROM_ISR(pxQueue); |
| 876 | |
| 877 | prvCopyDataFromQueue(pxQueue, pvBuffer); |
| 878 | --(pxQueue->uxMessagesWaiting); |
| 879 | |
| 880 | /* If the queue is locked we will not modify the event list. Instead |
| 881 | we update the lock count so the task that unlocks the queue will know |
| 882 | that an ISR has removed data while the queue was locked. */ |
| 883 | if (pxQueue->xRxLock == queueUNLOCKED) { |
| 884 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToSend))) { |
| 885 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToSend)) != pdFALSE) { |
| 886 | /* The task waiting has a higher priority than us so |
| 887 | force a context switch. */ |
| 888 | *pxTaskWoken = pdTRUE; |
| 889 | } |
| 890 | } |
| 891 | } else { |
| 892 | /* Increment the lock count so the task that unlocks the queue |
| 893 | knows that data was removed while it was locked. */ |
| 894 | ++(pxQueue->xRxLock); |
| 895 | } |
| 896 | |
| 897 | xReturn = pdPASS; |
| 898 | } else { |
| 899 | xReturn = pdFAIL; |
| 900 | traceQUEUE_RECEIVE_FROM_ISR_FAILED(pxQueue); |
| 901 | } |
| 902 | } |
| 903 | portCLEAR_INTERRUPT_MASK_FROM_ISR(uxSavedInterruptStatus); |
| 904 | |
| 905 | return xReturn; |
| 906 | } |
| 907 | /*-----------------------------------------------------------*/ |
| 908 | |
| 909 | unsigned portBASE_TYPE uxQueueMessagesWaiting(const xQueueHandle pxQueue) |
| 910 | { |
| 911 | unsigned portBASE_TYPE uxReturn; |
| 912 | |
| 913 | taskENTER_CRITICAL(); |
| 914 | uxReturn = pxQueue->uxMessagesWaiting; |
| 915 | taskEXIT_CRITICAL(); |
| 916 | |
| 917 | return uxReturn; |
| 918 | } |
| 919 | /*-----------------------------------------------------------*/ |
| 920 | |
| 921 | unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR(const xQueueHandle pxQueue) |
| 922 | { |
| 923 | unsigned portBASE_TYPE uxReturn; |
| 924 | |
| 925 | uxReturn = pxQueue->uxMessagesWaiting; |
| 926 | |
| 927 | return uxReturn; |
| 928 | } |
| 929 | /*-----------------------------------------------------------*/ |
| 930 | |
| 931 | void vQueueDelete(xQueueHandle pxQueue) |
| 932 | { |
| 933 | traceQUEUE_DELETE(pxQueue); |
| 934 | vQueueUnregisterQueue(pxQueue); |
| 935 | vPortFree(pxQueue->pcHead); |
| 936 | vPortFree(pxQueue); |
| 937 | } |
| 938 | /*-----------------------------------------------------------*/ |
| 939 | |
| 940 | static void prvCopyDataToQueue(xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition) |
| 941 | { |
| 942 | if (pxQueue->uxItemSize == (unsigned portBASE_TYPE) 0) { |
| 943 | #if ( configUSE_MUTEXES == 1 ) |
| 944 | { |
| 945 | if (pxQueue->uxQueueType == queueQUEUE_IS_MUTEX) { |
| 946 | /* The mutex is no longer being held. */ |
| 947 | vTaskPriorityDisinherit((void *) pxQueue->pxMutexHolder); |
| 948 | pxQueue->pxMutexHolder = NULL; |
| 949 | } |
| 950 | } |
| 951 | #endif |
| 952 | } else if (xPosition == queueSEND_TO_BACK) { |
| 953 | memcpy((void *) pxQueue->pcWriteTo, pvItemToQueue, (unsigned) pxQueue->uxItemSize); |
| 954 | pxQueue->pcWriteTo += pxQueue->uxItemSize; |
| 955 | if (pxQueue->pcWriteTo >= pxQueue->pcTail) { |
| 956 | pxQueue->pcWriteTo = pxQueue->pcHead; |
| 957 | } |
| 958 | } else { |
| 959 | memcpy((void *) pxQueue->pcReadFrom, pvItemToQueue, (unsigned) pxQueue->uxItemSize); |
| 960 | pxQueue->pcReadFrom -= pxQueue->uxItemSize; |
| 961 | if (pxQueue->pcReadFrom < pxQueue->pcHead) { |
| 962 | pxQueue->pcReadFrom = (pxQueue->pcTail - pxQueue->uxItemSize); |
| 963 | } |
| 964 | } |
| 965 | |
| 966 | ++(pxQueue->uxMessagesWaiting); |
| 967 | } |
| 968 | /*-----------------------------------------------------------*/ |
| 969 | |
| 970 | static void prvCopyDataFromQueue(xQUEUE * const pxQueue, const void *pvBuffer) |
| 971 | { |
| 972 | if (pxQueue->uxQueueType != queueQUEUE_IS_MUTEX) { |
| 973 | pxQueue->pcReadFrom += pxQueue->uxItemSize; |
| 974 | if (pxQueue->pcReadFrom >= pxQueue->pcTail) { |
| 975 | pxQueue->pcReadFrom = pxQueue->pcHead; |
| 976 | } |
| 977 | memcpy((void *) pvBuffer, (void *) pxQueue->pcReadFrom, (unsigned) pxQueue->uxItemSize); |
| 978 | } |
| 979 | } |
| 980 | /*-----------------------------------------------------------*/ |
| 981 | |
| 982 | static void prvUnlockQueue(xQueueHandle pxQueue) |
| 983 | { |
| 984 | /* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */ |
| 985 | |
| 986 | /* The lock counts contains the number of extra data items placed or |
| 987 | removed from the queue while the queue was locked. When a queue is |
| 988 | locked items can be added or removed, but the event lists cannot be |
| 989 | updated. */ |
| 990 | taskENTER_CRITICAL(); |
| 991 | { |
| 992 | /* See if data was added to the queue while it was locked. */ |
| 993 | while (pxQueue->xTxLock > queueLOCKED_UNMODIFIED) { |
| 994 | /* Data was posted while the queue was locked. Are any tasks |
| 995 | blocked waiting for data to become available? */ |
| 996 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive))) { |
| 997 | /* Tasks that are removed from the event list will get added to |
| 998 | the pending ready list as the scheduler is still suspended. */ |
| 999 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) != pdFALSE) { |
| 1000 | /* The task waiting has a higher priority so record that a |
| 1001 | context switch is required. */ |
| 1002 | vTaskMissedYield(); |
| 1003 | } |
| 1004 | |
| 1005 | --(pxQueue->xTxLock); |
| 1006 | } else { |
| 1007 | break; |
| 1008 | } |
| 1009 | } |
| 1010 | |
| 1011 | pxQueue->xTxLock = queueUNLOCKED; |
| 1012 | } |
| 1013 | taskEXIT_CRITICAL(); |
| 1014 | |
| 1015 | /* Do the same for the Rx lock. */ |
| 1016 | taskENTER_CRITICAL(); |
| 1017 | { |
| 1018 | while (pxQueue->xRxLock > queueLOCKED_UNMODIFIED) { |
| 1019 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToSend))) { |
| 1020 | if (xTaskRemoveFromEventList(&(pxQueue->xTasksWaitingToSend)) != pdFALSE) { |
| 1021 | vTaskMissedYield(); |
| 1022 | } |
| 1023 | |
| 1024 | --(pxQueue->xRxLock); |
| 1025 | } else { |
| 1026 | break; |
| 1027 | } |
| 1028 | } |
| 1029 | |
| 1030 | pxQueue->xRxLock = queueUNLOCKED; |
| 1031 | } |
| 1032 | taskEXIT_CRITICAL(); |
| 1033 | } |
| 1034 | /*-----------------------------------------------------------*/ |
| 1035 | |
| 1036 | static signed portBASE_TYPE prvIsQueueEmpty(const xQueueHandle pxQueue) |
| 1037 | { |
| 1038 | signed portBASE_TYPE xReturn; |
| 1039 | |
| 1040 | taskENTER_CRITICAL(); |
| 1041 | xReturn = (pxQueue->uxMessagesWaiting == (unsigned portBASE_TYPE) 0); |
| 1042 | taskEXIT_CRITICAL(); |
| 1043 | |
| 1044 | return xReturn; |
| 1045 | } |
| 1046 | /*-----------------------------------------------------------*/ |
| 1047 | |
| 1048 | signed portBASE_TYPE xQueueIsQueueEmptyFromISR(const xQueueHandle pxQueue) |
| 1049 | { |
| 1050 | signed portBASE_TYPE xReturn; |
| 1051 | |
| 1052 | xReturn = (pxQueue->uxMessagesWaiting == (unsigned portBASE_TYPE) 0); |
| 1053 | |
| 1054 | return xReturn; |
| 1055 | } |
| 1056 | /*-----------------------------------------------------------*/ |
| 1057 | |
| 1058 | static signed portBASE_TYPE prvIsQueueFull(const xQueueHandle pxQueue) |
| 1059 | { |
| 1060 | signed portBASE_TYPE xReturn; |
| 1061 | |
| 1062 | taskENTER_CRITICAL(); |
| 1063 | xReturn = (pxQueue->uxMessagesWaiting == pxQueue->uxLength); |
| 1064 | taskEXIT_CRITICAL(); |
| 1065 | |
| 1066 | return xReturn; |
| 1067 | } |
| 1068 | /*-----------------------------------------------------------*/ |
| 1069 | |
| 1070 | signed portBASE_TYPE xQueueIsQueueFullFromISR(const xQueueHandle pxQueue) |
| 1071 | { |
| 1072 | signed portBASE_TYPE xReturn; |
| 1073 | |
| 1074 | xReturn = (pxQueue->uxMessagesWaiting == pxQueue->uxLength); |
| 1075 | |
| 1076 | return xReturn; |
| 1077 | } |
| 1078 | /*-----------------------------------------------------------*/ |
| 1079 | |
| 1080 | #if configUSE_CO_ROUTINES == 1 |
| 1081 | signed portBASE_TYPE xQueueCRSend(xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait) |
| 1082 | { |
| 1083 | signed portBASE_TYPE xReturn; |
| 1084 | |
| 1085 | /* If the queue is already full we may have to block. A critical section |
| 1086 | is required to prevent an interrupt removing something from the queue |
| 1087 | between the check to see if the queue is full and blocking on the queue. */ |
| 1088 | portDISABLE_INTERRUPTS(); |
| 1089 | { |
| 1090 | if (prvIsQueueFull(pxQueue)) { |
| 1091 | /* The queue is full - do we want to block or just leave without |
| 1092 | posting? */ |
| 1093 | if (xTicksToWait > (portTickType) 0) { |
| 1094 | /* As this is called from a coroutine we cannot block directly, but |
| 1095 | return indicating that we need to block. */ |
| 1096 | vCoRoutineAddToDelayedList(xTicksToWait, &(pxQueue->xTasksWaitingToSend)); |
| 1097 | portENABLE_INTERRUPTS(); |
| 1098 | return errQUEUE_BLOCKED; |
| 1099 | } else { |
| 1100 | portENABLE_INTERRUPTS(); |
| 1101 | return errQUEUE_FULL; |
| 1102 | } |
| 1103 | } |
| 1104 | } |
| 1105 | portENABLE_INTERRUPTS(); |
| 1106 | |
| 1107 | portNOP(); |
| 1108 | |
| 1109 | portDISABLE_INTERRUPTS(); |
| 1110 | { |
| 1111 | if (pxQueue->uxMessagesWaiting < pxQueue->uxLength) { |
| 1112 | /* There is room in the queue, copy the data into the queue. */ |
| 1113 | prvCopyDataToQueue(pxQueue, pvItemToQueue, queueSEND_TO_BACK); |
| 1114 | xReturn = pdPASS; |
| 1115 | |
| 1116 | /* Were any co-routines waiting for data to become available? */ |
| 1117 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive))) { |
| 1118 | /* In this instance the co-routine could be placed directly |
| 1119 | into the ready list as we are within a critical section. |
| 1120 | Instead the same pending ready list mechanism is used as if |
| 1121 | the event were caused from within an interrupt. */ |
| 1122 | if (xCoRoutineRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) != pdFALSE) { |
| 1123 | /* The co-routine waiting has a higher priority so record |
| 1124 | that a yield might be appropriate. */ |
| 1125 | xReturn = errQUEUE_YIELD; |
| 1126 | } |
| 1127 | } |
| 1128 | } else { |
| 1129 | xReturn = errQUEUE_FULL; |
| 1130 | } |
| 1131 | } |
| 1132 | portENABLE_INTERRUPTS(); |
| 1133 | |
| 1134 | return xReturn; |
| 1135 | } |
| 1136 | #endif |
| 1137 | /*-----------------------------------------------------------*/ |
| 1138 | |
| 1139 | #if configUSE_CO_ROUTINES == 1 |
| 1140 | signed portBASE_TYPE xQueueCRReceive(xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait) |
| 1141 | { |
| 1142 | signed portBASE_TYPE xReturn; |
| 1143 | |
| 1144 | /* If the queue is already empty we may have to block. A critical section |
| 1145 | is required to prevent an interrupt adding something to the queue |
| 1146 | between the check to see if the queue is empty and blocking on the queue. */ |
| 1147 | portDISABLE_INTERRUPTS(); |
| 1148 | { |
| 1149 | if (pxQueue->uxMessagesWaiting == (unsigned portBASE_TYPE) 0) { |
| 1150 | /* There are no messages in the queue, do we want to block or just |
| 1151 | leave with nothing? */ |
| 1152 | if (xTicksToWait > (portTickType) 0) { |
| 1153 | /* As this is a co-routine we cannot block directly, but return |
| 1154 | indicating that we need to block. */ |
| 1155 | vCoRoutineAddToDelayedList(xTicksToWait, &(pxQueue->xTasksWaitingToReceive)); |
| 1156 | portENABLE_INTERRUPTS(); |
| 1157 | return errQUEUE_BLOCKED; |
| 1158 | } else { |
| 1159 | portENABLE_INTERRUPTS(); |
| 1160 | return errQUEUE_FULL; |
| 1161 | } |
| 1162 | } |
| 1163 | } |
| 1164 | portENABLE_INTERRUPTS(); |
| 1165 | |
| 1166 | portNOP(); |
| 1167 | |
| 1168 | portDISABLE_INTERRUPTS(); |
| 1169 | { |
| 1170 | if (pxQueue->uxMessagesWaiting > (unsigned portBASE_TYPE) 0) { |
| 1171 | /* Data is available from the queue. */ |
| 1172 | pxQueue->pcReadFrom += pxQueue->uxItemSize; |
| 1173 | if (pxQueue->pcReadFrom >= pxQueue->pcTail) { |
| 1174 | pxQueue->pcReadFrom = pxQueue->pcHead; |
| 1175 | } |
| 1176 | --(pxQueue->uxMessagesWaiting); |
| 1177 | memcpy((void *) pvBuffer, (void *) pxQueue->pcReadFrom, (unsigned) pxQueue->uxItemSize); |
| 1178 | |
| 1179 | xReturn = pdPASS; |
| 1180 | |
| 1181 | /* Were any co-routines waiting for space to become available? */ |
| 1182 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToSend))) { |
| 1183 | /* In this instance the co-routine could be placed directly |
| 1184 | into the ready list as we are within a critical section. |
| 1185 | Instead the same pending ready list mechanism is used as if |
| 1186 | the event were caused from within an interrupt. */ |
| 1187 | if (xCoRoutineRemoveFromEventList(&(pxQueue->xTasksWaitingToSend)) != pdFALSE) { |
| 1188 | xReturn = errQUEUE_YIELD; |
| 1189 | } |
| 1190 | } |
| 1191 | } else { |
| 1192 | xReturn = pdFAIL; |
| 1193 | } |
| 1194 | } |
| 1195 | portENABLE_INTERRUPTS(); |
| 1196 | |
| 1197 | return xReturn; |
| 1198 | } |
| 1199 | #endif |
| 1200 | /*-----------------------------------------------------------*/ |
| 1201 | |
| 1202 | |
| 1203 | |
| 1204 | #if configUSE_CO_ROUTINES == 1 |
| 1205 | signed portBASE_TYPE xQueueCRSendFromISR(xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken) |
| 1206 | { |
| 1207 | /* Cannot block within an ISR so if there is no space on the queue then |
| 1208 | exit without doing anything. */ |
| 1209 | if (pxQueue->uxMessagesWaiting < pxQueue->uxLength) { |
| 1210 | prvCopyDataToQueue(pxQueue, pvItemToQueue, queueSEND_TO_BACK); |
| 1211 | |
| 1212 | /* We only want to wake one co-routine per ISR, so check that a |
| 1213 | co-routine has not already been woken. */ |
| 1214 | if (!xCoRoutinePreviouslyWoken) { |
| 1215 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToReceive))) { |
| 1216 | if (xCoRoutineRemoveFromEventList(&(pxQueue->xTasksWaitingToReceive)) != pdFALSE) { |
| 1217 | return pdTRUE; |
| 1218 | } |
| 1219 | } |
| 1220 | } |
| 1221 | } |
| 1222 | |
| 1223 | return xCoRoutinePreviouslyWoken; |
| 1224 | } |
| 1225 | #endif |
| 1226 | /*-----------------------------------------------------------*/ |
| 1227 | |
| 1228 | #if configUSE_CO_ROUTINES == 1 |
| 1229 | signed portBASE_TYPE xQueueCRReceiveFromISR(xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxCoRoutineWoken) |
| 1230 | { |
| 1231 | signed portBASE_TYPE xReturn; |
| 1232 | |
| 1233 | /* We cannot block from an ISR, so check there is data available. If |
| 1234 | not then just leave without doing anything. */ |
| 1235 | if (pxQueue->uxMessagesWaiting > (unsigned portBASE_TYPE) 0) { |
| 1236 | /* Copy the data from the queue. */ |
| 1237 | pxQueue->pcReadFrom += pxQueue->uxItemSize; |
| 1238 | if (pxQueue->pcReadFrom >= pxQueue->pcTail) { |
| 1239 | pxQueue->pcReadFrom = pxQueue->pcHead; |
| 1240 | } |
| 1241 | --(pxQueue->uxMessagesWaiting); |
| 1242 | memcpy((void *) pvBuffer, (void *) pxQueue->pcReadFrom, (unsigned) pxQueue->uxItemSize); |
| 1243 | |
| 1244 | if (!(*pxCoRoutineWoken)) { |
| 1245 | if (!listLIST_IS_EMPTY(&(pxQueue->xTasksWaitingToSend))) { |
| 1246 | if (xCoRoutineRemoveFromEventList(&(pxQueue->xTasksWaitingToSend)) != pdFALSE) { |
| 1247 | *pxCoRoutineWoken = pdTRUE; |
| 1248 | } |
| 1249 | } |
| 1250 | } |
| 1251 | |
| 1252 | xReturn = pdPASS; |
| 1253 | } else { |
| 1254 | xReturn = pdFAIL; |
| 1255 | } |
| 1256 | |
| 1257 | return xReturn; |
| 1258 | } |
| 1259 | #endif |
| 1260 | /*-----------------------------------------------------------*/ |
| 1261 | |
| 1262 | #if configQUEUE_REGISTRY_SIZE > 0 |
| 1263 | |
| 1264 | void vQueueAddToRegistry(xQueueHandle xQueue, signed char *pcQueueName) |
| 1265 | { |
| 1266 | unsigned portBASE_TYPE ux; |
| 1267 | |
| 1268 | /* See if there is an empty space in the registry. A NULL name denotes |
| 1269 | a free slot. */ |
| 1270 | for (ux = 0; ux < configQUEUE_REGISTRY_SIZE; ux++) { |
| 1271 | if (xQueueRegistry[ ux ].pcQueueName == NULL) { |
| 1272 | /* Store the information on this queue. */ |
| 1273 | xQueueRegistry[ ux ].pcQueueName = pcQueueName; |
| 1274 | xQueueRegistry[ ux ].xHandle = xQueue; |
| 1275 | break; |
| 1276 | } |
| 1277 | } |
| 1278 | } |
| 1279 | |
| 1280 | #endif |
| 1281 | /*-----------------------------------------------------------*/ |
| 1282 | |
| 1283 | #if configQUEUE_REGISTRY_SIZE > 0 |
| 1284 | |
| 1285 | static void vQueueUnregisterQueue(xQueueHandle xQueue) |
| 1286 | { |
| 1287 | unsigned portBASE_TYPE ux; |
| 1288 | |
| 1289 | /* See if the handle of the queue being unregistered in actually in the |
| 1290 | registry. */ |
| 1291 | for (ux = 0; ux < configQUEUE_REGISTRY_SIZE; ux++) { |
| 1292 | if (xQueueRegistry[ ux ].xHandle == xQueue) { |
| 1293 | /* Set the name to NULL to show that this slot if free again. */ |
| 1294 | xQueueRegistry[ ux ].pcQueueName = NULL; |
| 1295 | break; |
| 1296 | } |
| 1297 | } |
| 1298 | |
| 1299 | } |
| 1300 | |
| 1301 | #endif |
| 1302 | |