git.sur5r.net Git - freertos/blob - FreeRTOS/Source/queue.c

   1 /*\r
   2     FreeRTOS V7.4.2 - Copyright (C) 2013 Real Time Engineers Ltd.\r
   3 \r
   4     FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME.  PLEASE VISIT\r
   5     http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.\r
   6 \r
   7     ***************************************************************************\r
   8      *                                                                       *\r
   9      *    FreeRTOS tutorial books are available in pdf and paperback.        *\r
  10      *    Complete, revised, and edited pdf reference manuals are also       *\r
  11      *    available.                                                         *\r
  12      *                                                                       *\r
  13      *    Purchasing FreeRTOS documentation will not only help you, by       *\r
  14      *    ensuring you get running as quickly as possible and with an        *\r
  15      *    in-depth knowledge of how to use FreeRTOS, it will also help       *\r
  16      *    the FreeRTOS project to continue with its mission of providing     *\r
  17      *    professional grade, cross platform, de facto standard solutions    *\r
  18      *    for microcontrollers - completely free of charge!                  *\r
  19      *                                                                       *\r
  20      *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *\r
  21      *                                                                       *\r
  22      *    Thank you for using FreeRTOS, and thank you for your support!      *\r
  23      *                                                                       *\r
  24     ***************************************************************************\r
  25 \r
  26 \r
  27     This file is part of the FreeRTOS distribution.\r
  28 \r
  29     FreeRTOS is free software; you can redistribute it and/or modify it under\r
  30     the terms of the GNU General Public License (version 2) as published by the\r
  31     Free Software Foundation AND MODIFIED BY the FreeRTOS exception.\r
  32 \r
  33     >>>>>>NOTE<<<<<< The modification to the GPL is included to allow you to\r
  34     distribute a combined work that includes FreeRTOS without being obliged to\r
  35     provide the source code for proprietary components outside of the FreeRTOS\r
  36     kernel.\r
  37 \r
  38     FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY\r
  39     WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS\r
  40     FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more\r
  41     details. You should have received a copy of the GNU General Public License\r
  42     and the FreeRTOS license exception along with FreeRTOS; if not it can be\r
  43     viewed here: http://www.freertos.org/a00114.html and also obtained by\r
  44     writing to Real Time Engineers Ltd., contact details for whom are available\r
  45     on the FreeRTOS WEB site.\r
  46 \r
  47     1 tab == 4 spaces!\r
  48 \r
  49     ***************************************************************************\r
  50      *                                                                       *\r
  51      *    Having a problem?  Start by reading the FAQ "My application does   *\r
  52      *    not run, what could be wrong?"                                     *\r
  53      *                                                                       *\r
  54      *    http://www.FreeRTOS.org/FAQHelp.html                               *\r
  55      *                                                                       *\r
  56     ***************************************************************************\r
  57 \r
  58 \r
  59     http://www.FreeRTOS.org - Documentation, books, training, latest versions,\r
  60     license and Real Time Engineers Ltd. contact details.\r
  61 \r
  62     http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,\r
  63     including FreeRTOS+Trace - an indispensable productivity tool, and our new\r
  64     fully thread aware and reentrant UDP/IP stack.\r
  65 \r
  66     http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High\r
  67     Integrity Systems, who sell the code with commercial support,\r
  68     indemnification and middleware, under the OpenRTOS brand.\r
  69 \r
  70     http://www.SafeRTOS.com - High Integrity Systems also provide a safety\r
  71     engineered and independently SIL3 certified version for use in safety and\r
  72     mission critical applications that require provable dependability.\r
  73 */\r
  74 \r
  75 #include <stdlib.h>\r
  76 #include <string.h>\r
  77 \r
  78 /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining\r
  79 all the API functions to use the MPU wrappers.  That should only be done when\r
  80 task.h is included from an application file. */\r
  81 #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE\r
  82 \r
  83 #include "FreeRTOS.h"\r
  84 #include "task.h"\r
  85 #include "queue.h"\r
  86 \r
  87 #if ( configUSE_CO_ROUTINES == 1 )\r
  88         #include "croutine.h"\r
  89 #endif\r
  90 \r
  91 #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE\r
  92 \r
  93 /* Constants used with the cRxLock and xTxLock structure members. */\r
  94 #define queueUNLOCKED                                   ( ( signed portBASE_TYPE ) -1 )\r
  95 #define queueLOCKED_UNMODIFIED                  ( ( signed portBASE_TYPE ) 0 )\r
  96 \r
  97 #define queueERRONEOUS_UNBLOCK                  ( -1 )\r
  98 \r
  99 /* When the xQUEUE structure is used to represent a base queue its pcHead and\r
 100 pcTail members are used as pointers into the queue storage area.  When the\r
 101 xQUEUE structure is used to represent a mutex pcHead and pcTail pointers are\r
 102 not necessary, and the pcHead pointer is set to NULL to indicate that the\r
 103 pcTail pointer actually points to the mutex holder (if any).  Map alternative\r
 104 names to the pcHead and pcTail structure members to ensure the readability of\r
 105 the code is maintained despite this dual use of two structure members.  An\r
 106 alternative implementation would be to use a union, but use of a union is\r
 107 against the coding standard (although an exception to the standard has been\r
 108 permitted where the dual use also significantly changes the type of the\r
 109 structure member). */\r
 110 #define pxMutexHolder                                   pcTail\r
 111 #define uxQueueType                                             pcHead\r
 112 #define queueQUEUE_IS_MUTEX                             NULL\r
 113 \r
 114 /* Semaphores do not actually store or copy data, so have an item size of\r
 115 zero. */\r
 116 #define queueSEMAPHORE_QUEUE_ITEM_LENGTH ( ( unsigned portBASE_TYPE ) 0 )\r
 117 #define queueDONT_BLOCK                                  ( ( portTickType ) 0U )\r
 118 #define queueMUTEX_GIVE_BLOCK_TIME               ( ( portTickType ) 0U )\r
 119 \r
 120 \r
 121 /*\r
 122  * Definition of the queue used by the scheduler.\r
 123  * Items are queued by copy, not reference.\r
 124  */\r
 125 typedef struct QueueDefinition\r
 126 {\r
 127         signed char *pcHead;                                    /*< Points to the beginning of the queue storage area. */\r
 128         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. */\r
 129 \r
 130         signed char *pcWriteTo;                                 /*< Points to the free next place in the storage area. */\r
 131 \r
 132         union                                                                   /* Use of a union is an exception to the coding standard to ensure two mutually exclusive structure members don't appear simultaneously (wasting RAM). */\r
 133         {\r
 134                 signed char *pcReadFrom;                        /*< Points to the last place that a queued item was read from when the structure is used as a queue. */\r
 135                 unsigned portBASE_TYPE uxRecursiveCallCount;/*< Maintains a count of the numebr of times a recursive mutex has been recursively 'taken' when the structure is used as a mutex. */\r
 136         } u;\r
 137 \r
 138         xList xTasksWaitingToSend;                              /*< List of tasks that are blocked waiting to post onto this queue.  Stored in priority order. */\r
 139         xList xTasksWaitingToReceive;                   /*< List of tasks that are blocked waiting to read from this queue.  Stored in priority order. */\r
 140 \r
 141         volatile unsigned portBASE_TYPE uxMessagesWaiting;/*< The number of items currently in the queue. */\r
 142         unsigned portBASE_TYPE uxLength;                /*< The length of the queue defined as the number of items it will hold, not the number of bytes. */\r
 143         unsigned portBASE_TYPE uxItemSize;              /*< The size of each items that the queue will hold. */\r
 144 \r
 145         volatile 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. */\r
 146         volatile 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. */\r
 147 \r
 148         #if ( configUSE_TRACE_FACILITY == 1 )\r
 149                 unsigned char ucQueueNumber;\r
 150                 unsigned char ucQueueType;\r
 151         #endif\r
 152 \r
 153         #if ( configUSE_QUEUE_SETS == 1 )\r
 154                 struct QueueDefinition *pxQueueSetContainer;\r
 155         #endif\r
 156 \r
 157 } xQUEUE;\r
 158 /*-----------------------------------------------------------*/\r
 159 \r
 160 /*\r
 161  * The queue registry is just a means for kernel aware debuggers to locate\r
 162  * queue structures.  It has no other purpose so is an optional component.\r
 163  */\r
 164 #if ( configQUEUE_REGISTRY_SIZE > 0 )\r
 165 \r
 166         /* The type stored within the queue registry array.  This allows a name\r
 167         to be assigned to each queue making kernel aware debugging a little\r
 168         more user friendly. */\r
 169         typedef struct QUEUE_REGISTRY_ITEM\r
 170         {\r
 171                 signed char *pcQueueName;\r
 172                 xQueueHandle xHandle;\r
 173         } xQueueRegistryItem;\r
 174 \r
 175         /* The queue registry is simply an array of xQueueRegistryItem structures.\r
 176         The pcQueueName member of a structure being NULL is indicative of the\r
 177         array position being vacant. */\r
 178         xQueueRegistryItem xQueueRegistry[ configQUEUE_REGISTRY_SIZE ];\r
 179 \r
 180 #endif /* configQUEUE_REGISTRY_SIZE */\r
 181 \r
 182 /*\r
 183  * Unlocks a queue locked by a call to prvLockQueue.  Locking a queue does not\r
 184  * prevent an ISR from adding or removing items to the queue, but does prevent\r
 185  * an ISR from removing tasks from the queue event lists.  If an ISR finds a\r
 186  * queue is locked it will instead increment the appropriate queue lock count\r
 187  * to indicate that a task may require unblocking.  When the queue in unlocked\r
 188  * these lock counts are inspected, and the appropriate action taken.\r
 189  */\r
 190 static void prvUnlockQueue( xQUEUE *pxQueue ) PRIVILEGED_FUNCTION;\r
 191 \r
 192 /*\r
 193  * Uses a critical section to determine if there is any data in a queue.\r
 194  *\r
 195  * @return pdTRUE if the queue contains no items, otherwise pdFALSE.\r
 196  */\r
 197 static signed portBASE_TYPE prvIsQueueEmpty( const xQUEUE *pxQueue ) PRIVILEGED_FUNCTION;\r
 198 \r
 199 /*\r
 200  * Uses a critical section to determine if there is any space in a queue.\r
 201  *\r
 202  * @return pdTRUE if there is no space, otherwise pdFALSE;\r
 203  */\r
 204 static signed portBASE_TYPE prvIsQueueFull( const xQUEUE *pxQueue ) PRIVILEGED_FUNCTION;\r
 205 \r
 206 /*\r
 207  * Copies an item into the queue, either at the front of the queue or the\r
 208  * back of the queue.\r
 209  */\r
 210 static void prvCopyDataToQueue( xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition ) PRIVILEGED_FUNCTION;\r
 211 \r
 212 /*\r
 213  * Copies an item out of a queue.\r
 214  */\r
 215 static void prvCopyDataFromQueue( xQUEUE * const pxQueue, const void *pvBuffer ) PRIVILEGED_FUNCTION;\r
 216 \r
 217 #if ( configUSE_QUEUE_SETS == 1 )\r
 218         /*\r
 219          * Checks to see if a queue is a member of a queue set, and if so, notifies\r
 220          * the queue set that the queue contains data.\r
 221          */\r
 222         static portBASE_TYPE prvNotifyQueueSetContainer( xQUEUE *pxQueue, portBASE_TYPE xCopyPosition ) PRIVILEGED_FUNCTION;\r
 223 #endif\r
 224 \r
 225 /*-----------------------------------------------------------*/\r
 226 \r
 227 /*\r
 228  * Macro to mark a queue as locked.  Locking a queue prevents an ISR from\r
 229  * accessing the queue event lists.\r
 230  */\r
 231 #define prvLockQueue( pxQueue )                                                         \\r
 232         taskENTER_CRITICAL();                                                                   \\r
 233         {                                                                                                               \\r
 234                 if( ( pxQueue )->xRxLock == queueUNLOCKED )                     \\r
 235                 {                                                                                                       \\r
 236                         ( pxQueue )->xRxLock = queueLOCKED_UNMODIFIED;  \\r
 237                 }                                                                                                       \\r
 238                 if( ( pxQueue )->xTxLock == queueUNLOCKED )                     \\r
 239                 {                                                                                                       \\r
 240                         ( pxQueue )->xTxLock = queueLOCKED_UNMODIFIED;  \\r
 241                 }                                                                                                       \\r
 242         }                                                                                                               \\r
 243         taskEXIT_CRITICAL()\r
 244 /*-----------------------------------------------------------*/\r
 245 \r
 246 portBASE_TYPE xQueueGenericReset( xQueueHandle xQueue, portBASE_TYPE xNewQueue )\r
 247 {\r
 248 xQUEUE *pxQueue;\r
 249 \r
 250         pxQueue = ( xQUEUE * ) xQueue;\r
 251         configASSERT( pxQueue );\r
 252 \r
 253         taskENTER_CRITICAL();\r
 254         {\r
 255                 pxQueue->pcTail = pxQueue->pcHead + ( pxQueue->uxLength * pxQueue->uxItemSize );\r
 256                 pxQueue->uxMessagesWaiting = ( unsigned portBASE_TYPE ) 0U;\r
 257                 pxQueue->pcWriteTo = pxQueue->pcHead;\r
 258                 pxQueue->u.pcReadFrom = pxQueue->pcHead + ( ( pxQueue->uxLength - ( unsigned portBASE_TYPE ) 1U ) * pxQueue->uxItemSize );\r
 259                 pxQueue->xRxLock = queueUNLOCKED;\r
 260                 pxQueue->xTxLock = queueUNLOCKED;\r
 261 \r
 262                 if( xNewQueue == pdFALSE )\r
 263                 {\r
 264                         /* If there are tasks blocked waiting to read from the queue, then\r
 265                         the tasks will remain blocked as after this function exits the queue\r
 266                         will still be empty.  If there are tasks blocked waiting to     write to\r
 267                         the queue, then one should be unblocked as after this function exits\r
 268                         it will be possible to write to it. */\r
 269                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
 270                         {\r
 271                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )\r
 272                                 {\r
 273                                         portYIELD_WITHIN_API();\r
 274                                 }\r
 275                         }\r
 276                 }\r
 277                 else\r
 278                 {\r
 279                         /* Ensure the event queues start in the correct state. */\r
 280                         vListInitialise( &( pxQueue->xTasksWaitingToSend ) );\r
 281                         vListInitialise( &( pxQueue->xTasksWaitingToReceive ) );\r
 282                 }\r
 283         }\r
 284         taskEXIT_CRITICAL();\r
 285 \r
 286         /* A value is returned for calling semantic consistency with previous\r
 287         versions. */\r
 288         return pdPASS;\r
 289 }\r
 290 /*-----------------------------------------------------------*/\r
 291 \r
 292 xQueueHandle xQueueGenericCreate( unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize, unsigned char ucQueueType )\r
 293 {\r
 294 xQUEUE *pxNewQueue;\r
 295 size_t xQueueSizeInBytes;\r
 296 xQueueHandle xReturn = NULL;\r
 297 \r
 298         /* Remove compiler warnings about unused parameters should\r
 299         configUSE_TRACE_FACILITY not be set to 1. */\r
 300         ( void ) ucQueueType;\r
 301 \r
 302         /* Allocate the new queue structure. */\r
 303         if( uxQueueLength > ( unsigned portBASE_TYPE ) 0 )\r
 304         {\r
 305                 pxNewQueue = ( xQUEUE * ) pvPortMalloc( sizeof( xQUEUE ) );\r
 306                 if( pxNewQueue != NULL )\r
 307                 {\r
 308                         /* Create the list of pointers to queue items.  The queue is one byte\r
 309                         longer than asked for to make wrap checking easier/faster. */\r
 310                         xQueueSizeInBytes = ( size_t ) ( uxQueueLength * uxItemSize ) + ( size_t ) 1;\r
 311 \r
 312                         pxNewQueue->pcHead = ( signed char * ) pvPortMalloc( xQueueSizeInBytes );\r
 313                         if( pxNewQueue->pcHead != NULL )\r
 314                         {\r
 315                                 /* Initialise the queue members as described above where the\r
 316                                 queue type is defined. */\r
 317                                 pxNewQueue->uxLength = uxQueueLength;\r
 318                                 pxNewQueue->uxItemSize = uxItemSize;\r
 319                                 xQueueGenericReset( pxNewQueue, pdTRUE );\r
 320 \r
 321                                 #if ( configUSE_TRACE_FACILITY == 1 )\r
 322                                 {\r
 323                                         pxNewQueue->ucQueueType = ucQueueType;\r
 324                                 }\r
 325                                 #endif /* configUSE_TRACE_FACILITY */\r
 326 \r
 327                                 #if( configUSE_QUEUE_SETS == 1 )\r
 328                                 {\r
 329                                         pxNewQueue->pxQueueSetContainer = NULL;\r
 330                                 }\r
 331                                 #endif /* configUSE_QUEUE_SETS */\r
 332 \r
 333                                 traceQUEUE_CREATE( pxNewQueue );\r
 334                                 xReturn = pxNewQueue;\r
 335                         }\r
 336                         else\r
 337                         {\r
 338                                 traceQUEUE_CREATE_FAILED( ucQueueType );\r
 339                                 vPortFree( pxNewQueue );\r
 340                         }\r
 341                 }\r
 342         }\r
 343 \r
 344         configASSERT( xReturn );\r
 345 \r
 346         return xReturn;\r
 347 }\r
 348 /*-----------------------------------------------------------*/\r
 349 \r
 350 #if ( configUSE_MUTEXES == 1 )\r
 351 \r
 352         xQueueHandle xQueueCreateMutex( unsigned char ucQueueType )\r
 353         {\r
 354         xQUEUE *pxNewQueue;\r
 355 \r
 356                 /* Prevent compiler warnings about unused parameters if\r
 357                 configUSE_TRACE_FACILITY does not equal 1. */\r
 358                 ( void ) ucQueueType;\r
 359 \r
 360                 /* Allocate the new queue structure. */\r
 361                 pxNewQueue = ( xQUEUE * ) pvPortMalloc( sizeof( xQUEUE ) );\r
 362                 if( pxNewQueue != NULL )\r
 363                 {\r
 364                         /* Information required for priority inheritance. */\r
 365                         pxNewQueue->pxMutexHolder = NULL;\r
 366                         pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX;\r
 367 \r
 368                         /* Queues used as a mutex no data is actually copied into or out\r
 369                         of the queue. */\r
 370                         pxNewQueue->pcWriteTo = NULL;\r
 371                         pxNewQueue->u.pcReadFrom = NULL;\r
 372 \r
 373                         /* Each mutex has a length of 1 (like a binary semaphore) and\r
 374                         an item size of 0 as nothing is actually copied into or out\r
 375                         of the mutex. */\r
 376                         pxNewQueue->uxMessagesWaiting = ( unsigned portBASE_TYPE ) 0U;\r
 377                         pxNewQueue->uxLength = ( unsigned portBASE_TYPE ) 1U;\r
 378                         pxNewQueue->uxItemSize = ( unsigned portBASE_TYPE ) 0U;\r
 379                         pxNewQueue->xRxLock = queueUNLOCKED;\r
 380                         pxNewQueue->xTxLock = queueUNLOCKED;\r
 381 \r
 382                         #if ( configUSE_TRACE_FACILITY == 1 )\r
 383                         {\r
 384                                 pxNewQueue->ucQueueType = ucQueueType;\r
 385                         }\r
 386                         #endif\r
 387 \r
 388                         #if ( configUSE_QUEUE_SETS == 1 )\r
 389                         {\r
 390                                 pxNewQueue->pxQueueSetContainer = NULL;\r
 391                         }\r
 392                         #endif\r
 393 \r
 394                         /* Ensure the event queues start with the correct state. */\r
 395                         vListInitialise( &( pxNewQueue->xTasksWaitingToSend ) );\r
 396                         vListInitialise( &( pxNewQueue->xTasksWaitingToReceive ) );\r
 397 \r
 398                         traceCREATE_MUTEX( pxNewQueue );\r
 399 \r
 400                         /* Start with the semaphore in the expected state. */\r
 401                         xQueueGenericSend( pxNewQueue, NULL, ( portTickType ) 0U, queueSEND_TO_BACK );\r
 402                 }\r
 403                 else\r
 404                 {\r
 405                         traceCREATE_MUTEX_FAILED();\r
 406                 }\r
 407 \r
 408                 configASSERT( pxNewQueue );\r
 409                 return pxNewQueue;\r
 410         }\r
 411 \r
 412 #endif /* configUSE_MUTEXES */\r
 413 /*-----------------------------------------------------------*/\r
 414 \r
 415 #if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xSemaphoreGetMutexHolder == 1 ) )\r
 416 \r
 417         void* xQueueGetMutexHolder( xQueueHandle xSemaphore )\r
 418         {\r
 419         void *pxReturn;\r
 420 \r
 421                 /* This function is called by xSemaphoreGetMutexHolder(), and should not\r
 422                 be called directly.  Note:  This is is a good way of determining if the\r
 423                 calling task is the mutex holder, but not a good way of determining the\r
 424                 identity of the mutex holder, as the holder may change between the\r
 425                 following critical section exiting and the function returning. */\r
 426                 taskENTER_CRITICAL();\r
 427                 {\r
 428                         if( ( ( xQUEUE * ) xSemaphore )->uxQueueType == queueQUEUE_IS_MUTEX )\r
 429                         {\r
 430                                 pxReturn = ( void * ) ( ( xQUEUE * ) xSemaphore )->pxMutexHolder;\r
 431                         }\r
 432                         else\r
 433                         {\r
 434                                 pxReturn = NULL;\r
 435                         }\r
 436                 }\r
 437                 taskEXIT_CRITICAL();\r
 438 \r
 439                 return pxReturn;\r
 440         }\r
 441 \r
 442 #endif\r
 443 /*-----------------------------------------------------------*/\r
 444 \r
 445 #if ( configUSE_RECURSIVE_MUTEXES == 1 )\r
 446 \r
 447         portBASE_TYPE xQueueGiveMutexRecursive( xQueueHandle xMutex )\r
 448         {\r
 449         portBASE_TYPE xReturn;\r
 450         xQUEUE *pxMutex;\r
 451 \r
 452                 pxMutex = ( xQUEUE * ) xMutex;\r
 453                 configASSERT( pxMutex );\r
 454 \r
 455                 /* If this is the task that holds the mutex then pxMutexHolder will not\r
 456                 change outside of this task.  If this task does not hold the mutex then\r
 457                 pxMutexHolder can never coincidentally equal the tasks handle, and as\r
 458                 this is the only condition we are interested in it does not matter if\r
 459                 pxMutexHolder is accessed simultaneously by another task.  Therefore no\r
 460                 mutual exclusion is required to test the pxMutexHolder variable. */\r
 461                 if( pxMutex->pxMutexHolder == ( void * ) xTaskGetCurrentTaskHandle() )\r
 462                 {\r
 463                         traceGIVE_MUTEX_RECURSIVE( pxMutex );\r
 464 \r
 465                         /* uxRecursiveCallCount cannot be zero if pxMutexHolder is equal to\r
 466                         the task handle, therefore no underflow check is required.  Also,\r
 467                         uxRecursiveCallCount is only modified by the mutex holder, and as\r
 468                         there can only be one, no mutual exclusion is required to modify the\r
 469                         uxRecursiveCallCount member. */\r
 470                         ( pxMutex->u.uxRecursiveCallCount )--;\r
 471 \r
 472                         /* Have we unwound the call count? */\r
 473                         if( pxMutex->u.uxRecursiveCallCount == 0 )\r
 474                         {\r
 475                                 /* Return the mutex.  This will automatically unblock any other\r
 476                                 task that might be waiting to access the mutex. */\r
 477                                 xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK );\r
 478                         }\r
 479 \r
 480                         xReturn = pdPASS;\r
 481                 }\r
 482                 else\r
 483                 {\r
 484                         /* We cannot give the mutex because we are not the holder. */\r
 485                         xReturn = pdFAIL;\r
 486 \r
 487                         traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex );\r
 488                 }\r
 489 \r
 490                 return xReturn;\r
 491         }\r
 492 \r
 493 #endif /* configUSE_RECURSIVE_MUTEXES */\r
 494 /*-----------------------------------------------------------*/\r
 495 \r
 496 #if ( configUSE_RECURSIVE_MUTEXES == 1 )\r
 497 \r
 498         portBASE_TYPE xQueueTakeMutexRecursive( xQueueHandle xMutex, portTickType xBlockTime )\r
 499         {\r
 500         portBASE_TYPE xReturn;\r
 501         xQUEUE *pxMutex;\r
 502 \r
 503                 pxMutex = ( xQUEUE * ) xMutex;\r
 504                 configASSERT( pxMutex );\r
 505 \r
 506                 /* Comments regarding mutual exclusion as per those within\r
 507                 xQueueGiveMutexRecursive(). */\r
 508 \r
 509                 traceTAKE_MUTEX_RECURSIVE( pxMutex );\r
 510 \r
 511                 if( pxMutex->pxMutexHolder == ( void * )  xTaskGetCurrentTaskHandle() )\r
 512                 {\r
 513                         ( pxMutex->u.uxRecursiveCallCount )++;\r
 514                         xReturn = pdPASS;\r
 515                 }\r
 516                 else\r
 517                 {\r
 518                         xReturn = xQueueGenericReceive( pxMutex, NULL, xBlockTime, pdFALSE );\r
 519 \r
 520                         /* pdPASS will only be returned if we successfully obtained the mutex,\r
 521                         we may have blocked to reach here. */\r
 522                         if( xReturn == pdPASS )\r
 523                         {\r
 524                                 ( pxMutex->u.uxRecursiveCallCount )++;\r
 525                         }\r
 526                         else\r
 527                         {\r
 528                                 traceTAKE_MUTEX_RECURSIVE_FAILED( pxMutex );\r
 529                         }\r
 530                 }\r
 531 \r
 532                 return xReturn;\r
 533         }\r
 534 \r
 535 #endif /* configUSE_RECURSIVE_MUTEXES */\r
 536 /*-----------------------------------------------------------*/\r
 537 \r
 538 #if ( configUSE_COUNTING_SEMAPHORES == 1 )\r
 539 \r
 540         xQueueHandle xQueueCreateCountingSemaphore( unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount )\r
 541         {\r
 542         xQueueHandle xHandle;\r
 543 \r
 544                 xHandle = xQueueGenericCreate( ( unsigned portBASE_TYPE ) uxCountValue, queueSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_COUNTING_SEMAPHORE );\r
 545 \r
 546                 if( xHandle != NULL )\r
 547                 {\r
 548                         ( ( xQUEUE * ) xHandle )->uxMessagesWaiting = uxInitialCount;\r
 549 \r
 550                         traceCREATE_COUNTING_SEMAPHORE();\r
 551                 }\r
 552                 else\r
 553                 {\r
 554                         traceCREATE_COUNTING_SEMAPHORE_FAILED();\r
 555                 }\r
 556 \r
 557                 configASSERT( xHandle );\r
 558                 return xHandle;\r
 559         }\r
 560 \r
 561 #endif /* configUSE_COUNTING_SEMAPHORES */\r
 562 /*-----------------------------------------------------------*/\r
 563 \r
 564 signed portBASE_TYPE xQueueGenericSend( xQueueHandle xQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition )\r
 565 {\r
 566 signed portBASE_TYPE xEntryTimeSet = pdFALSE;\r
 567 xTimeOutType xTimeOut;\r
 568 xQUEUE *pxQueue;\r
 569 \r
 570         pxQueue = ( xQUEUE * ) xQueue;\r
 571         configASSERT( pxQueue );\r
 572         configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) );\r
 573         configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );\r
 574 \r
 575         /* This function relaxes the coding standard somewhat to allow return\r
 576         statements within the function itself.  This is done in the interest\r
 577         of execution time efficiency. */\r
 578         for( ;; )\r
 579         {\r
 580                 taskENTER_CRITICAL();\r
 581                 {\r
 582                         /* Is there room on the queue now?  The running task must be\r
 583                         the highest priority task wanting to access the queue.  If\r
 584                         the head item in the queue is to be overwritten then it does\r
 585                         not matter if the queue is full. */\r
 586                         if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) || ( xCopyPosition == queueOVERWRITE ) )\r
 587                         {\r
 588                                 traceQUEUE_SEND( pxQueue );\r
 589                                 prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );\r
 590 \r
 591                                 #if ( configUSE_QUEUE_SETS == 1 )\r
 592                                 {\r
 593                                         if( pxQueue->pxQueueSetContainer != NULL )\r
 594                                         {\r
 595                                                 if( prvNotifyQueueSetContainer( pxQueue, xCopyPosition ) == pdTRUE )\r
 596                                                 {\r
 597                                                         /* The queue is a member of a queue set, and posting\r
 598                                                         to the queue set caused a higher priority task to\r
 599                                                         unblock. A context switch is required. */\r
 600                                                         portYIELD_WITHIN_API();\r
 601                                                 }\r
 602                                         }\r
 603                                         else\r
 604                                         {\r
 605                                                 /* If there was a task waiting for data to arrive on the\r
 606                                                 queue then unblock it now. */\r
 607                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
 608                                                 {\r
 609                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )\r
 610                                                         {\r
 611                                                                 /* The unblocked task has a priority higher than\r
 612                                                                 our own so yield immediately.  Yes it is ok to\r
 613                                                                 do this from within the critical section - the\r
 614                                                                 kernel takes care of that. */\r
 615                                                                 portYIELD_WITHIN_API();\r
 616                                                         }\r
 617                                                 }\r
 618                                         }\r
 619                                 }\r
 620                                 #else /* configUSE_QUEUE_SETS */\r
 621                                 {\r
 622                                         /* If there was a task waiting for data to arrive on the\r
 623                                         queue then unblock it now. */\r
 624                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
 625                                         {\r
 626                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )\r
 627                                                 {\r
 628                                                         /* The unblocked task has a priority higher than\r
 629                                                         our own so yield immediately.  Yes it is ok to do\r
 630                                                         this from within the critical section - the kernel\r
 631                                                         takes care of that. */\r
 632                                                         portYIELD_WITHIN_API();\r
 633                                                 }\r
 634                                         }\r
 635                                 }\r
 636                                 #endif /* configUSE_QUEUE_SETS */\r
 637 \r
 638                                 taskEXIT_CRITICAL();\r
 639 \r
 640                                 /* Return to the original privilege level before exiting the\r
 641                                 function. */\r
 642                                 return pdPASS;\r
 643                         }\r
 644                         else\r
 645                         {\r
 646                                 if( xTicksToWait == ( portTickType ) 0 )\r
 647                                 {\r
 648                                         /* The queue was full and no block time is specified (or\r
 649                                         the block time has expired) so leave now. */\r
 650                                         taskEXIT_CRITICAL();\r
 651 \r
 652                                         /* Return to the original privilege level before exiting\r
 653                                         the function. */\r
 654                                         traceQUEUE_SEND_FAILED( pxQueue );\r
 655                                         return errQUEUE_FULL;\r
 656                                 }\r
 657                                 else if( xEntryTimeSet == pdFALSE )\r
 658                                 {\r
 659                                         /* The queue was full and a block time was specified so\r
 660                                         configure the timeout structure. */\r
 661                                         vTaskSetTimeOutState( &xTimeOut );\r
 662                                         xEntryTimeSet = pdTRUE;\r
 663                                 }\r
 664                         }\r
 665                 }\r
 666                 taskEXIT_CRITICAL();\r
 667 \r
 668                 /* Interrupts and other tasks can send to and receive from the queue\r
 669                 now the critical section has been exited. */\r
 670 \r
 671                 vTaskSuspendAll();\r
 672                 prvLockQueue( pxQueue );\r
 673 \r
 674                 /* Update the timeout state to see if it has expired yet. */\r
 675                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )\r
 676                 {\r
 677                         if( prvIsQueueFull( pxQueue ) != pdFALSE )\r
 678                         {\r
 679                                 traceBLOCKING_ON_QUEUE_SEND( pxQueue );\r
 680                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );\r
 681 \r
 682                                 /* Unlocking the queue means queue events can effect the\r
 683                                 event list.  It is possible     that interrupts occurring now\r
 684                                 remove this task from the event list again - but as the\r
 685                                 scheduler is suspended the task will go onto the pending\r
 686                                 ready last instead of the actual ready list. */\r
 687                                 prvUnlockQueue( pxQueue );\r
 688 \r
 689                                 /* Resuming the scheduler will move tasks from the pending\r
 690                                 ready list into the ready list - so it is feasible that this\r
 691                                 task is already in a ready list before it yields - in which\r
 692                                 case the yield will not cause a context switch unless there\r
 693                                 is also a higher priority task in the pending ready list. */\r
 694                                 if( xTaskResumeAll() == pdFALSE )\r
 695                                 {\r
 696                                         portYIELD_WITHIN_API();\r
 697                                 }\r
 698                         }\r
 699                         else\r
 700                         {\r
 701                                 /* Try again. */\r
 702                                 prvUnlockQueue( pxQueue );\r
 703                                 ( void ) xTaskResumeAll();\r
 704                         }\r
 705                 }\r
 706                 else\r
 707                 {\r
 708                         /* The timeout has expired. */\r
 709                         prvUnlockQueue( pxQueue );\r
 710                         ( void ) xTaskResumeAll();\r
 711 \r
 712                         /* Return to the original privilege level before exiting the\r
 713                         function. */\r
 714                         traceQUEUE_SEND_FAILED( pxQueue );\r
 715                         return errQUEUE_FULL;\r
 716                 }\r
 717         }\r
 718 }\r
 719 /*-----------------------------------------------------------*/\r
 720 \r
 721 #if ( configUSE_ALTERNATIVE_API == 1 )\r
 722 \r
 723         signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle xQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition )\r
 724         {\r
 725         signed portBASE_TYPE xEntryTimeSet = pdFALSE;\r
 726         xTimeOutType xTimeOut;\r
 727         xQUEUE *pxQueue;\r
 728 \r
 729                 pxQueue = ( xQUEUE * ) xQueue;\r
 730                 configASSERT( pxQueue );\r
 731                 configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) );\r
 732 \r
 733                 for( ;; )\r
 734                 {\r
 735                         taskENTER_CRITICAL();\r
 736                         {\r
 737                                 /* Is there room on the queue now?  To be running we must be\r
 738                                 the highest priority task wanting to access the queue. */\r
 739                                 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )\r
 740                                 {\r
 741                                         traceQUEUE_SEND( pxQueue );\r
 742                                         prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );\r
 743 \r
 744                                         /* If there was a task waiting for data to arrive on the\r
 745                                         queue then unblock it now. */\r
 746                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
 747                                         {\r
 748                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )\r
 749                                                 {\r
 750                                                         /* The unblocked task has a priority higher than\r
 751                                                         our own so yield immediately. */\r
 752                                                         portYIELD_WITHIN_API();\r
 753                                                 }\r
 754                                         }\r
 755 \r
 756                                         taskEXIT_CRITICAL();\r
 757                                         return pdPASS;\r
 758                                 }\r
 759                                 else\r
 760                                 {\r
 761                                         if( xTicksToWait == ( portTickType ) 0 )\r
 762                                         {\r
 763                                                 taskEXIT_CRITICAL();\r
 764                                                 return errQUEUE_FULL;\r
 765                                         }\r
 766                                         else if( xEntryTimeSet == pdFALSE )\r
 767                                         {\r
 768                                                 vTaskSetTimeOutState( &xTimeOut );\r
 769                                                 xEntryTimeSet = pdTRUE;\r
 770                                         }\r
 771                                 }\r
 772                         }\r
 773                         taskEXIT_CRITICAL();\r
 774 \r
 775                         taskENTER_CRITICAL();\r
 776                         {\r
 777                                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )\r
 778                                 {\r
 779                                         if( prvIsQueueFull( pxQueue ) != pdFALSE )\r
 780                                         {\r
 781                                                 traceBLOCKING_ON_QUEUE_SEND( pxQueue );\r
 782                                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );\r
 783                                                 portYIELD_WITHIN_API();\r
 784                                         }\r
 785                                 }\r
 786                                 else\r
 787                                 {\r
 788                                         taskEXIT_CRITICAL();\r
 789                                         traceQUEUE_SEND_FAILED( pxQueue );\r
 790                                         return errQUEUE_FULL;\r
 791                                 }\r
 792                         }\r
 793                         taskEXIT_CRITICAL();\r
 794                 }\r
 795         }\r
 796 \r
 797 #endif /* configUSE_ALTERNATIVE_API */\r
 798 /*-----------------------------------------------------------*/\r
 799 \r
 800 #if ( configUSE_ALTERNATIVE_API == 1 )\r
 801 \r
 802         signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle xQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking )\r
 803         {\r
 804         signed portBASE_TYPE xEntryTimeSet = pdFALSE;\r
 805         xTimeOutType xTimeOut;\r
 806         signed char *pcOriginalReadPosition;\r
 807         xQUEUE *pxQueue;\r
 808 \r
 809                 pxQueue = ( xQUEUE * ) xQueue;\r
 810                 configASSERT( pxQueue );\r
 811                 configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) );\r
 812 \r
 813                 for( ;; )\r
 814                 {\r
 815                         taskENTER_CRITICAL();\r
 816                         {\r
 817                                 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )\r
 818                                 {\r
 819                                         /* Remember our read position in case we are just peeking. */\r
 820                                         pcOriginalReadPosition = pxQueue->u.pcReadFrom;\r
 821 \r
 822                                         prvCopyDataFromQueue( pxQueue, pvBuffer );\r
 823 \r
 824                                         if( xJustPeeking == pdFALSE )\r
 825                                         {\r
 826                                                 traceQUEUE_RECEIVE( pxQueue );\r
 827 \r
 828                                                 /* We are actually removing data. */\r
 829                                                 --( pxQueue->uxMessagesWaiting );\r
 830 \r
 831                                                 #if ( configUSE_MUTEXES == 1 )\r
 832                                                 {\r
 833                                                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )\r
 834                                                         {\r
 835                                                                 /* Record the information required to implement\r
 836                                                                 priority inheritance should it become necessary. */\r
 837                                                                 pxQueue->pxMutexHolder = ( void * ) xTaskGetCurrentTaskHandle();\r
 838                                                         }\r
 839                                                 }\r
 840                                                 #endif\r
 841 \r
 842                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
 843                                                 {\r
 844                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )\r
 845                                                         {\r
 846                                                                 portYIELD_WITHIN_API();\r
 847                                                         }\r
 848                                                 }\r
 849                                         }\r
 850                                         else\r
 851                                         {\r
 852                                                 traceQUEUE_PEEK( pxQueue );\r
 853 \r
 854                                                 /* We are not removing the data, so reset our read\r
 855                                                 pointer. */\r
 856                                                 pxQueue->u.pcReadFrom = pcOriginalReadPosition;\r
 857 \r
 858                                                 /* The data is being left in the queue, so see if there are\r
 859                                                 any other tasks waiting for the data. */\r
 860                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
 861                                                 {\r
 862                                                         /* Tasks that are removed from the event list will get added to\r
 863                                                         the pending ready list as the scheduler is still suspended. */\r
 864                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
 865                                                         {\r
 866                                                                 /* The task waiting has a higher priority than this task. */\r
 867                                                                 portYIELD_WITHIN_API();\r
 868                                                         }\r
 869                                                 }\r
 870 \r
 871                                         }\r
 872 \r
 873                                         taskEXIT_CRITICAL();\r
 874                                         return pdPASS;\r
 875                                 }\r
 876                                 else\r
 877                                 {\r
 878                                         if( xTicksToWait == ( portTickType ) 0 )\r
 879                                         {\r
 880                                                 taskEXIT_CRITICAL();\r
 881                                                 traceQUEUE_RECEIVE_FAILED( pxQueue );\r
 882                                                 return errQUEUE_EMPTY;\r
 883                                         }\r
 884                                         else if( xEntryTimeSet == pdFALSE )\r
 885                                         {\r
 886                                                 vTaskSetTimeOutState( &xTimeOut );\r
 887                                                 xEntryTimeSet = pdTRUE;\r
 888                                         }\r
 889                                 }\r
 890                         }\r
 891                         taskEXIT_CRITICAL();\r
 892 \r
 893                         taskENTER_CRITICAL();\r
 894                         {\r
 895                                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )\r
 896                                 {\r
 897                                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )\r
 898                                         {\r
 899                                                 traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );\r
 900 \r
 901                                                 #if ( configUSE_MUTEXES == 1 )\r
 902                                                 {\r
 903                                                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )\r
 904                                                         {\r
 905                                                                 portENTER_CRITICAL();\r
 906                                                                 {\r
 907                                                                         vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );\r
 908                                                                 }\r
 909                                                                 portEXIT_CRITICAL();\r
 910                                                         }\r
 911                                                 }\r
 912                                                 #endif\r
 913 \r
 914                                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );\r
 915                                                 portYIELD_WITHIN_API();\r
 916                                         }\r
 917                                 }\r
 918                                 else\r
 919                                 {\r
 920                                         taskEXIT_CRITICAL();\r
 921                                         traceQUEUE_RECEIVE_FAILED( pxQueue );\r
 922                                         return errQUEUE_EMPTY;\r
 923                                 }\r
 924                         }\r
 925                         taskEXIT_CRITICAL();\r
 926                 }\r
 927         }\r
 928 \r
 929 \r
 930 #endif /* configUSE_ALTERNATIVE_API */\r
 931 /*-----------------------------------------------------------*/\r
 932 \r
 933 signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle xQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition )\r
 934 {\r
 935 signed portBASE_TYPE xReturn;\r
 936 unsigned portBASE_TYPE uxSavedInterruptStatus;\r
 937 xQUEUE *pxQueue;\r
 938 \r
 939         pxQueue = ( xQUEUE * ) xQueue;\r
 940         configASSERT( pxQueue );\r
 941         configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) );\r
 942 \r
 943         /* Similar to xQueueGenericSend, except we don't block if there is no room\r
 944         in the queue.  Also we don't directly wake a task that was blocked on a\r
 945         queue read, instead we return a flag to say whether a context switch is\r
 946         required or not (i.e. has a task with a higher priority than us been woken\r
 947         by this post). */\r
 948         uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();\r
 949         {\r
 950                 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )\r
 951                 {\r
 952                         traceQUEUE_SEND_FROM_ISR( pxQueue );\r
 953 \r
 954                         prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );\r
 955 \r
 956                         /* If the queue is locked we do not alter the event list.  This will\r
 957                         be done when the queue is unlocked later. */\r
 958                         if( pxQueue->xTxLock == queueUNLOCKED )\r
 959                         {\r
 960                                 #if ( configUSE_QUEUE_SETS == 1 )\r
 961                                 {\r
 962                                         if( pxQueue->pxQueueSetContainer != NULL )\r
 963                                         {\r
 964                                                 if( prvNotifyQueueSetContainer( pxQueue, xCopyPosition ) == pdTRUE )\r
 965                                                 {\r
 966                                                         /* The queue is a member of a queue set, and posting\r
 967                                                         to the queue set caused a higher priority task to\r
 968                                                         unblock.  A context switch is required. */\r
 969                                                         if( pxHigherPriorityTaskWoken != NULL )\r
 970                                                         {\r
 971                                                                 *pxHigherPriorityTaskWoken = pdTRUE;\r
 972                                                         }\r
 973                                                 }\r
 974                                         }\r
 975                                         else\r
 976                                         {\r
 977                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
 978                                                 {\r
 979                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
 980                                                         {\r
 981                                                                 /* The task waiting has a higher priority so record that a\r
 982                                                                 context switch is required. */\r
 983                                                                 if( pxHigherPriorityTaskWoken != NULL )\r
 984                                                                 {\r
 985                                                                         *pxHigherPriorityTaskWoken = pdTRUE;\r
 986                                                                 }\r
 987                                                         }\r
 988                                                 }\r
 989                                         }\r
 990                                 }\r
 991                                 #else /* configUSE_QUEUE_SETS */\r
 992                                 {\r
 993                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
 994                                         {\r
 995                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
 996                                                 {\r
 997                                                         /* The task waiting has a higher priority so record that a\r
 998                                                         context switch is required. */\r
 999                                                         if( pxHigherPriorityTaskWoken != NULL )\r
1000                                                         {\r
1001                                                                 *pxHigherPriorityTaskWoken = pdTRUE;\r
1002                                                         }\r
1003                                                 }\r
1004                                         }\r
1005                                 }\r
1006                                 #endif /* configUSE_QUEUE_SETS */\r
1007                         }\r
1008                         else\r
1009                         {\r
1010                                 /* Increment the lock count so the task that unlocks the queue\r
1011                                 knows that data was posted while it was locked. */\r
1012                                 ++( pxQueue->xTxLock );\r
1013                         }\r
1014 \r
1015                         xReturn = pdPASS;\r
1016                 }\r
1017                 else\r
1018                 {\r
1019                         traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );\r
1020                         xReturn = errQUEUE_FULL;\r
1021                 }\r
1022         }\r
1023         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );\r
1024 \r
1025         return xReturn;\r
1026 }\r
1027 /*-----------------------------------------------------------*/\r
1028 \r
1029 signed portBASE_TYPE xQueueGenericReceive( xQueueHandle xQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking )\r
1030 {\r
1031 signed portBASE_TYPE xEntryTimeSet = pdFALSE;\r
1032 xTimeOutType xTimeOut;\r
1033 signed char *pcOriginalReadPosition;\r
1034 xQUEUE *pxQueue;\r
1035 \r
1036         pxQueue = ( xQUEUE * ) xQueue;\r
1037         configASSERT( pxQueue );\r
1038         configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) );\r
1039 \r
1040         /* This function relaxes the coding standard somewhat to allow return\r
1041         statements within the function itself.  This is done in the interest\r
1042         of execution time efficiency. */\r
1043 \r
1044         for( ;; )\r
1045         {\r
1046                 taskENTER_CRITICAL();\r
1047                 {\r
1048                         /* Is there data in the queue now?  To be running we must be\r
1049                         the highest priority task wanting to access the queue. */\r
1050                         if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )\r
1051                         {\r
1052                                 /* Remember the read position in case the queue is only being \r
1053                                 peeked. */\r
1054                                 pcOriginalReadPosition = pxQueue->u.pcReadFrom;\r
1055 \r
1056                                 prvCopyDataFromQueue( pxQueue, pvBuffer );\r
1057 \r
1058                                 if( xJustPeeking == pdFALSE )\r
1059                                 {\r
1060                                         traceQUEUE_RECEIVE( pxQueue );\r
1061 \r
1062                                         /* We are actually removing data. */\r
1063                                         --( pxQueue->uxMessagesWaiting );\r
1064 \r
1065                                         #if ( configUSE_MUTEXES == 1 )\r
1066                                         {\r
1067                                                 if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )\r
1068                                                 {\r
1069                                                         /* Record the information required to implement\r
1070                                                         priority inheritance should it become necessary. */\r
1071                                                         pxQueue->pxMutexHolder = ( void * ) xTaskGetCurrentTaskHandle();\r
1072                                                 }\r
1073                                         }\r
1074                                         #endif\r
1075 \r
1076                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
1077                                         {\r
1078                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )\r
1079                                                 {\r
1080                                                         portYIELD_WITHIN_API();\r
1081                                                 }\r
1082                                         }\r
1083                                 }\r
1084                                 else\r
1085                                 {\r
1086                                         traceQUEUE_PEEK( pxQueue );\r
1087 \r
1088                                         /* The data is not being removed, so reset the read\r
1089                                         pointer. */\r
1090                                         pxQueue->u.pcReadFrom = pcOriginalReadPosition;\r
1091 \r
1092                                         /* The data is being left in the queue, so see if there are\r
1093                                         any other tasks waiting for the data. */\r
1094                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
1095                                         {\r
1096                                                 /* Tasks that are removed from the event list will get added to\r
1097                                                 the pending ready list as the scheduler is still suspended. */\r
1098                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
1099                                                 {\r
1100                                                         /* The task waiting has a higher priority than this task. */\r
1101                                                         portYIELD_WITHIN_API();\r
1102                                                 }\r
1103                                         }\r
1104                                 }\r
1105 \r
1106                                 taskEXIT_CRITICAL();\r
1107                                 return pdPASS;\r
1108                         }\r
1109                         else\r
1110                         {\r
1111                                 if( xTicksToWait == ( portTickType ) 0 )\r
1112                                 {\r
1113                                         /* The queue was empty and no block time is specified (or\r
1114                                         the block time has expired) so leave now. */\r
1115                                         taskEXIT_CRITICAL();\r
1116                                         traceQUEUE_RECEIVE_FAILED( pxQueue );\r
1117                                         return errQUEUE_EMPTY;\r
1118                                 }\r
1119                                 else if( xEntryTimeSet == pdFALSE )\r
1120                                 {\r
1121                                         /* The queue was empty and a block time was specified so\r
1122                                         configure the timeout structure. */\r
1123                                         vTaskSetTimeOutState( &xTimeOut );\r
1124                                         xEntryTimeSet = pdTRUE;\r
1125                                 }\r
1126                         }\r
1127                 }\r
1128                 taskEXIT_CRITICAL();\r
1129 \r
1130                 /* Interrupts and other tasks can send to and receive from the queue\r
1131                 now the critical section has been exited. */\r
1132 \r
1133                 vTaskSuspendAll();\r
1134                 prvLockQueue( pxQueue );\r
1135 \r
1136                 /* Update the timeout state to see if it has expired yet. */\r
1137                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )\r
1138                 {\r
1139                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )\r
1140                         {\r
1141                                 traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );\r
1142 \r
1143                                 #if ( configUSE_MUTEXES == 1 )\r
1144                                 {\r
1145                                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )\r
1146                                         {\r
1147                                                 portENTER_CRITICAL();\r
1148                                                 {\r
1149                                                         vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );\r
1150                                                 }\r
1151                                                 portEXIT_CRITICAL();\r
1152                                         }\r
1153                                 }\r
1154                                 #endif\r
1155 \r
1156                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );\r
1157                                 prvUnlockQueue( pxQueue );\r
1158                                 if( xTaskResumeAll() == pdFALSE )\r
1159                                 {\r
1160                                         portYIELD_WITHIN_API();\r
1161                                 }\r
1162                         }\r
1163                         else\r
1164                         {\r
1165                                 /* Try again. */\r
1166                                 prvUnlockQueue( pxQueue );\r
1167                                 ( void ) xTaskResumeAll();\r
1168                         }\r
1169                 }\r
1170                 else\r
1171                 {\r
1172                         prvUnlockQueue( pxQueue );\r
1173                         ( void ) xTaskResumeAll();\r
1174                         traceQUEUE_RECEIVE_FAILED( pxQueue );\r
1175                         return errQUEUE_EMPTY;\r
1176                 }\r
1177         }\r
1178 }\r
1179 /*-----------------------------------------------------------*/\r
1180 \r
1181 signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle xQueue, void * const pvBuffer, signed portBASE_TYPE *pxHigherPriorityTaskWoken )\r
1182 {\r
1183 signed portBASE_TYPE xReturn;\r
1184 unsigned portBASE_TYPE uxSavedInterruptStatus;\r
1185 xQUEUE *pxQueue;\r
1186 \r
1187         pxQueue = ( xQUEUE * ) xQueue;\r
1188         configASSERT( pxQueue );\r
1189         configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) );\r
1190 \r
1191         uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();\r
1192         {\r
1193                 /* We cannot block from an ISR, so check there is data available. */\r
1194                 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )\r
1195                 {\r
1196                         traceQUEUE_RECEIVE_FROM_ISR( pxQueue );\r
1197 \r
1198                         prvCopyDataFromQueue( pxQueue, pvBuffer );\r
1199                         --( pxQueue->uxMessagesWaiting );\r
1200 \r
1201                         /* If the queue is locked we will not modify the event list.  Instead\r
1202                         we update the lock count so the task that unlocks the queue will know\r
1203                         that an ISR has removed data while the queue was locked. */\r
1204                         if( pxQueue->xRxLock == queueUNLOCKED )\r
1205                         {\r
1206                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
1207                                 {\r
1208                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )\r
1209                                         {\r
1210                                                 /* The task waiting has a higher priority than us so\r
1211                                                 force a context switch. */\r
1212                                                 if( pxHigherPriorityTaskWoken != NULL )\r
1213                                                 {\r
1214                                                         *pxHigherPriorityTaskWoken = pdTRUE;\r
1215                                                 }\r
1216                                         }\r
1217                                 }\r
1218                         }\r
1219                         else\r
1220                         {\r
1221                                 /* Increment the lock count so the task that unlocks the queue\r
1222                                 knows that data was removed while it was locked. */\r
1223                                 ++( pxQueue->xRxLock );\r
1224                         }\r
1225 \r
1226                         xReturn = pdPASS;\r
1227                 }\r
1228                 else\r
1229                 {\r
1230                         xReturn = pdFAIL;\r
1231                         traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue );\r
1232                 }\r
1233         }\r
1234         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );\r
1235 \r
1236         return xReturn;\r
1237 }\r
1238 /*-----------------------------------------------------------*/\r
1239 \r
1240 unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle xQueue )\r
1241 {\r
1242 unsigned portBASE_TYPE uxReturn;\r
1243 \r
1244         configASSERT( xQueue );\r
1245 \r
1246         taskENTER_CRITICAL();\r
1247                 uxReturn = ( ( xQUEUE * ) xQueue )->uxMessagesWaiting;\r
1248         taskEXIT_CRITICAL();\r
1249 \r
1250         return uxReturn;\r
1251 }\r
1252 /*-----------------------------------------------------------*/\r
1253 \r
1254 unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR( const xQueueHandle xQueue )\r
1255 {\r
1256 unsigned portBASE_TYPE uxReturn;\r
1257 \r
1258         configASSERT( xQueue );\r
1259 \r
1260         uxReturn = ( ( xQUEUE * ) xQueue )->uxMessagesWaiting;\r
1261 \r
1262         return uxReturn;\r
1263 }\r
1264 /*-----------------------------------------------------------*/\r
1265 \r
1266 void vQueueDelete( xQueueHandle xQueue )\r
1267 {\r
1268 xQUEUE *pxQueue;\r
1269 \r
1270         pxQueue = ( xQUEUE * ) xQueue;\r
1271         configASSERT( pxQueue );\r
1272 \r
1273         traceQUEUE_DELETE( pxQueue );\r
1274         #if ( configQUEUE_REGISTRY_SIZE > 0 )\r
1275         {\r
1276                 vQueueUnregisterQueue( pxQueue );\r
1277         }\r
1278         #endif\r
1279         vPortFree( pxQueue->pcHead );\r
1280         vPortFree( pxQueue );\r
1281 }\r
1282 /*-----------------------------------------------------------*/\r
1283 \r
1284 #if ( configUSE_TRACE_FACILITY == 1 )\r
1285 \r
1286         unsigned char ucQueueGetQueueNumber( xQueueHandle xQueue )\r
1287         {\r
1288                 return ( ( xQUEUE * ) xQueue )->ucQueueNumber;\r
1289         }\r
1290 \r
1291 #endif /* configUSE_TRACE_FACILITY */\r
1292 /*-----------------------------------------------------------*/\r
1293 \r
1294 #if ( configUSE_TRACE_FACILITY == 1 )\r
1295 \r
1296         void vQueueSetQueueNumber( xQueueHandle xQueue, unsigned char ucQueueNumber )\r
1297         {\r
1298                 ( ( xQUEUE * ) xQueue )->ucQueueNumber = ucQueueNumber;\r
1299         }\r
1300 \r
1301 #endif /* configUSE_TRACE_FACILITY */\r
1302 /*-----------------------------------------------------------*/\r
1303 \r
1304 #if ( configUSE_TRACE_FACILITY == 1 )\r
1305 \r
1306         unsigned char ucQueueGetQueueType( xQueueHandle xQueue )\r
1307         {\r
1308                 return ( ( xQUEUE * ) xQueue )->ucQueueType;\r
1309         }\r
1310 \r
1311 #endif /* configUSE_TRACE_FACILITY */\r
1312 /*-----------------------------------------------------------*/\r
1313 \r
1314 static void prvCopyDataToQueue( xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition )\r
1315 {\r
1316         if( pxQueue->uxItemSize == ( unsigned portBASE_TYPE ) 0 )\r
1317         {\r
1318                 #if ( configUSE_MUTEXES == 1 )\r
1319                 {\r
1320                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )\r
1321                         {\r
1322                                 /* The mutex is no longer being held. */\r
1323                                 vTaskPriorityDisinherit( ( void * ) pxQueue->pxMutexHolder );\r
1324                                 pxQueue->pxMutexHolder = NULL;\r
1325                         }\r
1326                 }\r
1327                 #endif /* configUSE_MUTEXES */\r
1328         }\r
1329         else if( xPosition == queueSEND_TO_BACK )\r
1330         {\r
1331                 memcpy( ( void * ) pxQueue->pcWriteTo, pvItemToQueue, ( size_t ) pxQueue->uxItemSize );\r
1332                 pxQueue->pcWriteTo += pxQueue->uxItemSize;\r
1333                 if( pxQueue->pcWriteTo >= pxQueue->pcTail )\r
1334                 {\r
1335                         pxQueue->pcWriteTo = pxQueue->pcHead;\r
1336                 }\r
1337         }\r
1338         else\r
1339         {\r
1340                 memcpy( ( void * ) pxQueue->u.pcReadFrom, pvItemToQueue, ( size_t ) pxQueue->uxItemSize );\r
1341                 pxQueue->u.pcReadFrom -= pxQueue->uxItemSize;\r
1342                 if( pxQueue->u.pcReadFrom < pxQueue->pcHead )\r
1343                 {\r
1344                         pxQueue->u.pcReadFrom = ( pxQueue->pcTail - pxQueue->uxItemSize );\r
1345                 }\r
1346 \r
1347                 if( xPosition == queueOVERWRITE )\r
1348                 {\r
1349                         if( pxQueue->uxMessagesWaiting > 0 )\r
1350                         {\r
1351                                 /* An item is not being added but overwritten, so subtract \r
1352                                 one from the recorded number of items in the queue so when \r
1353                                 one is added again below the number of recorded items remains \r
1354                                 correct. */\r
1355                                 --( pxQueue->uxMessagesWaiting );\r
1356                         }\r
1357                 }\r
1358         }\r
1359 \r
1360         ++( pxQueue->uxMessagesWaiting );\r
1361 }\r
1362 /*-----------------------------------------------------------*/\r
1363 \r
1364 static void prvCopyDataFromQueue( xQUEUE * const pxQueue, const void *pvBuffer )\r
1365 {\r
1366         if( pxQueue->uxQueueType != queueQUEUE_IS_MUTEX )\r
1367         {\r
1368                 pxQueue->u.pcReadFrom += pxQueue->uxItemSize;\r
1369                 if( pxQueue->u.pcReadFrom >= pxQueue->pcTail )\r
1370                 {\r
1371                         pxQueue->u.pcReadFrom = pxQueue->pcHead;\r
1372                 }\r
1373                 memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.pcReadFrom, ( size_t ) pxQueue->uxItemSize );\r
1374         }\r
1375 }\r
1376 /*-----------------------------------------------------------*/\r
1377 \r
1378 static void prvUnlockQueue( xQUEUE *pxQueue )\r
1379 {\r
1380         /* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */\r
1381 \r
1382         /* The lock counts contains the number of extra data items placed or\r
1383         removed from the queue while the queue was locked.  When a queue is\r
1384         locked items can be added or removed, but the event lists cannot be\r
1385         updated. */\r
1386         taskENTER_CRITICAL();\r
1387         {\r
1388                 /* See if data was added to the queue while it was locked. */\r
1389                 while( pxQueue->xTxLock > queueLOCKED_UNMODIFIED )\r
1390                 {\r
1391                         /* Data was posted while the queue was locked.  Are any tasks\r
1392                         blocked waiting for data to become available? */\r
1393                         #if ( configUSE_QUEUE_SETS == 1 )\r
1394                         {\r
1395                                 if( pxQueue->pxQueueSetContainer != NULL )\r
1396                                 {\r
1397                                         if( prvNotifyQueueSetContainer( pxQueue, queueSEND_TO_BACK ) == pdTRUE )\r
1398                                         {\r
1399                                                 /* The queue is a member of a queue set, and posting to\r
1400                                                 the queue set caused a higher priority task to unblock.\r
1401                                                 A context switch is required. */\r
1402                                                 vTaskMissedYield();\r
1403                                         }\r
1404                                 }\r
1405                                 else\r
1406                                 {\r
1407                                         /* Tasks that are removed from the event list will get added to\r
1408                                         the pending ready list as the scheduler is still suspended. */\r
1409                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
1410                                         {\r
1411                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
1412                                                 {\r
1413                                                         /* The task waiting has a higher priority so record that a\r
1414                                                         context switch is required. */\r
1415                                                         vTaskMissedYield();\r
1416                                                 }\r
1417                                         }\r
1418                                         else\r
1419                                         {\r
1420                                                 break;\r
1421                                         }\r
1422                                 }\r
1423                         }\r
1424                         #else /* configUSE_QUEUE_SETS */\r
1425                         {\r
1426                                 /* Tasks that are removed from the event list will get added to\r
1427                                 the pending ready list as the scheduler is still suspended. */\r
1428                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
1429                                 {\r
1430                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
1431                                         {\r
1432                                                 /* The task waiting has a higher priority so record that a\r
1433                                                 context switch is required. */\r
1434                                                 vTaskMissedYield();\r
1435                                         }\r
1436                                 }\r
1437                                 else\r
1438                                 {\r
1439                                         break;\r
1440                                 }\r
1441                         }\r
1442                         #endif /* configUSE_QUEUE_SETS */\r
1443 \r
1444                         --( pxQueue->xTxLock );\r
1445                 }\r
1446 \r
1447                 pxQueue->xTxLock = queueUNLOCKED;\r
1448         }\r
1449         taskEXIT_CRITICAL();\r
1450 \r
1451         /* Do the same for the Rx lock. */\r
1452         taskENTER_CRITICAL();\r
1453         {\r
1454                 while( pxQueue->xRxLock > queueLOCKED_UNMODIFIED )\r
1455                 {\r
1456                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
1457                         {\r
1458                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )\r
1459                                 {\r
1460                                         vTaskMissedYield();\r
1461                                 }\r
1462 \r
1463                                 --( pxQueue->xRxLock );\r
1464                         }\r
1465                         else\r
1466                         {\r
1467                                 break;\r
1468                         }\r
1469                 }\r
1470 \r
1471                 pxQueue->xRxLock = queueUNLOCKED;\r
1472         }\r
1473         taskEXIT_CRITICAL();\r
1474 }\r
1475 /*-----------------------------------------------------------*/\r
1476 \r
1477 static signed portBASE_TYPE prvIsQueueEmpty( const xQUEUE *pxQueue )\r
1478 {\r
1479 signed portBASE_TYPE xReturn;\r
1480 \r
1481         taskENTER_CRITICAL();\r
1482         {\r
1483                 if( pxQueue->uxMessagesWaiting == 0 )\r
1484                 {\r
1485                         xReturn = pdTRUE;\r
1486                 }\r
1487                 else\r
1488                 {\r
1489                         xReturn = pdFALSE;\r
1490                 }\r
1491         }\r
1492         taskEXIT_CRITICAL();\r
1493 \r
1494         return xReturn;\r
1495 }\r
1496 /*-----------------------------------------------------------*/\r
1497 \r
1498 signed portBASE_TYPE xQueueIsQueueEmptyFromISR( const xQueueHandle xQueue )\r
1499 {\r
1500 signed portBASE_TYPE xReturn;\r
1501 \r
1502         configASSERT( xQueue );\r
1503         if( ( ( xQUEUE * ) xQueue )->uxMessagesWaiting == 0 )\r
1504         {\r
1505                 xReturn = pdTRUE;\r
1506         }\r
1507         else\r
1508         {\r
1509                 xReturn = pdFALSE;\r
1510         }\r
1511 \r
1512         return xReturn;\r
1513 }\r
1514 /*-----------------------------------------------------------*/\r
1515 \r
1516 static signed portBASE_TYPE prvIsQueueFull( const xQUEUE *pxQueue )\r
1517 {\r
1518 signed portBASE_TYPE xReturn;\r
1519 \r
1520         taskENTER_CRITICAL();\r
1521         {\r
1522                 if( pxQueue->uxMessagesWaiting == pxQueue->uxLength )\r
1523                 {\r
1524                         xReturn = pdTRUE;\r
1525                 }\r
1526                 else\r
1527                 {\r
1528                         xReturn = pdFALSE;\r
1529                 }\r
1530         }\r
1531         taskEXIT_CRITICAL();\r
1532 \r
1533         return xReturn;\r
1534 }\r
1535 /*-----------------------------------------------------------*/\r
1536 \r
1537 signed portBASE_TYPE xQueueIsQueueFullFromISR( const xQueueHandle xQueue )\r
1538 {\r
1539 signed portBASE_TYPE xReturn;\r
1540 \r
1541         configASSERT( xQueue );\r
1542         if( ( ( xQUEUE * ) xQueue )->uxMessagesWaiting == ( ( xQUEUE * ) xQueue )->uxLength )\r
1543         {\r
1544                 xReturn = pdTRUE;\r
1545         }\r
1546         else\r
1547         {\r
1548                 xReturn = pdFALSE;\r
1549         }\r
1550 \r
1551         return xReturn;\r
1552 }\r
1553 /*-----------------------------------------------------------*/\r
1554 \r
1555 #if ( configUSE_CO_ROUTINES == 1 )\r
1556 \r
1557         signed portBASE_TYPE xQueueCRSend( xQueueHandle xQueue, const void *pvItemToQueue, portTickType xTicksToWait )\r
1558         {\r
1559         signed portBASE_TYPE xReturn;\r
1560         xQUEUE *pxQueue;\r
1561 \r
1562                 pxQueue = ( xQUEUE * ) xQueue;\r
1563 \r
1564                 /* If the queue is already full we may have to block.  A critical section\r
1565                 is required to prevent an interrupt removing something from the queue\r
1566                 between the check to see if the queue is full and blocking on the queue. */\r
1567                 portDISABLE_INTERRUPTS();\r
1568                 {\r
1569                         if( prvIsQueueFull( pxQueue ) != pdFALSE )\r
1570                         {\r
1571                                 /* The queue is full - do we want to block or just leave without\r
1572                                 posting? */\r
1573                                 if( xTicksToWait > ( portTickType ) 0 )\r
1574                                 {\r
1575                                         /* As this is called from a coroutine we cannot block directly, but\r
1576                                         return indicating that we need to block. */\r
1577                                         vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) );\r
1578                                         portENABLE_INTERRUPTS();\r
1579                                         return errQUEUE_BLOCKED;\r
1580                                 }\r
1581                                 else\r
1582                                 {\r
1583                                         portENABLE_INTERRUPTS();\r
1584                                         return errQUEUE_FULL;\r
1585                                 }\r
1586                         }\r
1587                 }\r
1588                 portENABLE_INTERRUPTS();\r
1589 \r
1590                 portDISABLE_INTERRUPTS();\r
1591                 {\r
1592                         if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )\r
1593                         {\r
1594                                 /* There is room in the queue, copy the data into the queue. */\r
1595                                 prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );\r
1596                                 xReturn = pdPASS;\r
1597 \r
1598                                 /* Were any co-routines waiting for data to become available? */\r
1599                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
1600                                 {\r
1601                                         /* In this instance the co-routine could be placed directly\r
1602                                         into the ready list as we are within a critical section.\r
1603                                         Instead the same pending ready list mechanism is used as if\r
1604                                         the event were caused from within an interrupt. */\r
1605                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
1606                                         {\r
1607                                                 /* The co-routine waiting has a higher priority so record\r
1608                                                 that a yield might be appropriate. */\r
1609                                                 xReturn = errQUEUE_YIELD;\r
1610                                         }\r
1611                                 }\r
1612                         }\r
1613                         else\r
1614                         {\r
1615                                 xReturn = errQUEUE_FULL;\r
1616                         }\r
1617                 }\r
1618                 portENABLE_INTERRUPTS();\r
1619 \r
1620                 return xReturn;\r
1621         }\r
1622 \r
1623 #endif /* configUSE_CO_ROUTINES */\r
1624 /*-----------------------------------------------------------*/\r
1625 \r
1626 #if ( configUSE_CO_ROUTINES == 1 )\r
1627 \r
1628         signed portBASE_TYPE xQueueCRReceive( xQueueHandle xQueue, void *pvBuffer, portTickType xTicksToWait )\r
1629         {\r
1630         signed portBASE_TYPE xReturn;\r
1631         xQUEUE *pxQueue;\r
1632 \r
1633                 pxQueue = ( xQUEUE * ) xQueue;\r
1634 \r
1635                 /* If the queue is already empty we may have to block.  A critical section\r
1636                 is required to prevent an interrupt adding something to the queue\r
1637                 between the check to see if the queue is empty and blocking on the queue. */\r
1638                 portDISABLE_INTERRUPTS();\r
1639                 {\r
1640                         if( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 )\r
1641                         {\r
1642                                 /* There are no messages in the queue, do we want to block or just\r
1643                                 leave with nothing? */\r
1644                                 if( xTicksToWait > ( portTickType ) 0 )\r
1645                                 {\r
1646                                         /* As this is a co-routine we cannot block directly, but return\r
1647                                         indicating that we need to block. */\r
1648                                         vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) );\r
1649                                         portENABLE_INTERRUPTS();\r
1650                                         return errQUEUE_BLOCKED;\r
1651                                 }\r
1652                                 else\r
1653                                 {\r
1654                                         portENABLE_INTERRUPTS();\r
1655                                         return errQUEUE_FULL;\r
1656                                 }\r
1657                         }\r
1658                 }\r
1659                 portENABLE_INTERRUPTS();\r
1660 \r
1661                 portDISABLE_INTERRUPTS();\r
1662                 {\r
1663                         if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )\r
1664                         {\r
1665                                 /* Data is available from the queue. */\r
1666                                 pxQueue->u.pcReadFrom += pxQueue->uxItemSize;\r
1667                                 if( pxQueue->u.pcReadFrom >= pxQueue->pcTail )\r
1668                                 {\r
1669                                         pxQueue->u.pcReadFrom = pxQueue->pcHead;\r
1670                                 }\r
1671                                 --( pxQueue->uxMessagesWaiting );\r
1672                                 memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );\r
1673 \r
1674                                 xReturn = pdPASS;\r
1675 \r
1676                                 /* Were any co-routines waiting for space to become available? */\r
1677                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
1678                                 {\r
1679                                         /* In this instance the co-routine could be placed directly\r
1680                                         into the ready list as we are within a critical section.\r
1681                                         Instead the same pending ready list mechanism is used as if\r
1682                                         the event were caused from within an interrupt. */\r
1683                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )\r
1684                                         {\r
1685                                                 xReturn = errQUEUE_YIELD;\r
1686                                         }\r
1687                                 }\r
1688                         }\r
1689                         else\r
1690                         {\r
1691                                 xReturn = pdFAIL;\r
1692                         }\r
1693                 }\r
1694                 portENABLE_INTERRUPTS();\r
1695 \r
1696                 return xReturn;\r
1697         }\r
1698 \r
1699 #endif /* configUSE_CO_ROUTINES */\r
1700 /*-----------------------------------------------------------*/\r
1701 \r
1702 #if ( configUSE_CO_ROUTINES == 1 )\r
1703 \r
1704         signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle xQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken )\r
1705         {\r
1706         xQUEUE *pxQueue;\r
1707 \r
1708                 pxQueue = ( xQUEUE * ) xQueue;\r
1709 \r
1710                 /* Cannot block within an ISR so if there is no space on the queue then\r
1711                 exit without doing anything. */\r
1712                 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )\r
1713                 {\r
1714                         prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );\r
1715 \r
1716                         /* We only want to wake one co-routine per ISR, so check that a\r
1717                         co-routine has not already been woken. */\r
1718                         if( xCoRoutinePreviouslyWoken == pdFALSE )\r
1719                         {\r
1720                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )\r
1721                                 {\r
1722                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )\r
1723                                         {\r
1724                                                 return pdTRUE;\r
1725                                         }\r
1726                                 }\r
1727                         }\r
1728                 }\r
1729 \r
1730                 return xCoRoutinePreviouslyWoken;\r
1731         }\r
1732 \r
1733 #endif /* configUSE_CO_ROUTINES */\r
1734 /*-----------------------------------------------------------*/\r
1735 \r
1736 #if ( configUSE_CO_ROUTINES == 1 )\r
1737 \r
1738         signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle xQueue, void *pvBuffer, signed portBASE_TYPE *pxCoRoutineWoken )\r
1739         {\r
1740         signed portBASE_TYPE xReturn;\r
1741         xQUEUE * pxQueue;\r
1742 \r
1743                 pxQueue = ( xQUEUE * ) xQueue;\r
1744 \r
1745                 /* We cannot block from an ISR, so check there is data available. If\r
1746                 not then just leave without doing anything. */\r
1747                 if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )\r
1748                 {\r
1749                         /* Copy the data from the queue. */\r
1750                         pxQueue->u.pcReadFrom += pxQueue->uxItemSize;\r
1751                         if( pxQueue->u.pcReadFrom >= pxQueue->pcTail )\r
1752                         {\r
1753                                 pxQueue->u.pcReadFrom = pxQueue->pcHead;\r
1754                         }\r
1755                         --( pxQueue->uxMessagesWaiting );\r
1756                         memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );\r
1757 \r
1758                         if( ( *pxCoRoutineWoken ) == pdFALSE )\r
1759                         {\r
1760                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )\r
1761                                 {\r
1762                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )\r
1763                                         {\r
1764                                                 *pxCoRoutineWoken = pdTRUE;\r
1765                                         }\r
1766                                 }\r
1767                         }\r
1768 \r
1769                         xReturn = pdPASS;\r
1770                 }\r
1771                 else\r
1772                 {\r
1773                         xReturn = pdFAIL;\r
1774                 }\r
1775 \r
1776                 return xReturn;\r
1777         }\r
1778 \r
1779 #endif /* configUSE_CO_ROUTINES */\r
1780 /*-----------------------------------------------------------*/\r
1781 \r
1782 #if ( configQUEUE_REGISTRY_SIZE > 0 )\r
1783 \r
1784         void vQueueAddToRegistry( xQueueHandle xQueue, signed char *pcQueueName )\r
1785         {\r
1786         unsigned portBASE_TYPE ux;\r
1787 \r
1788                 /* See if there is an empty space in the registry.  A NULL name denotes\r
1789                 a free slot. */\r
1790                 for( ux = ( unsigned portBASE_TYPE ) 0U; ux < ( unsigned portBASE_TYPE ) configQUEUE_REGISTRY_SIZE; ux++ )\r
1791                 {\r
1792                         if( xQueueRegistry[ ux ].pcQueueName == NULL )\r
1793                         {\r
1794                                 /* Store the information on this queue. */\r
1795                                 xQueueRegistry[ ux ].pcQueueName = pcQueueName;\r
1796                                 xQueueRegistry[ ux ].xHandle = xQueue;\r
1797                                 break;\r
1798                         }\r
1799                 }\r
1800         }\r
1801 \r
1802 #endif /* configQUEUE_REGISTRY_SIZE */\r
1803 /*-----------------------------------------------------------*/\r
1804 \r
1805 #if ( configQUEUE_REGISTRY_SIZE > 0 )\r
1806 \r
1807         void vQueueUnregisterQueue( xQueueHandle xQueue )\r
1808         {\r
1809         unsigned portBASE_TYPE ux;\r
1810 \r
1811                 /* See if the handle of the queue being unregistered in actually in the\r
1812                 registry. */\r
1813                 for( ux = ( unsigned portBASE_TYPE ) 0U; ux < ( unsigned portBASE_TYPE ) configQUEUE_REGISTRY_SIZE; ux++ )\r
1814                 {\r
1815                         if( xQueueRegistry[ ux ].xHandle == xQueue )\r
1816                         {\r
1817                                 /* Set the name to NULL to show that this slot if free again. */\r
1818                                 xQueueRegistry[ ux ].pcQueueName = NULL;\r
1819                                 break;\r
1820                         }\r
1821                 }\r
1822 \r
1823         }\r
1824 \r
1825 #endif /* configQUEUE_REGISTRY_SIZE */\r
1826 /*-----------------------------------------------------------*/\r
1827 \r
1828 #if ( configUSE_TIMERS == 1 )\r
1829 \r
1830         void vQueueWaitForMessageRestricted( xQueueHandle xQueue, portTickType xTicksToWait )\r
1831         {\r
1832         xQUEUE *pxQueue;\r
1833 \r
1834                 pxQueue = ( xQUEUE * ) xQueue;\r
1835 \r
1836                 /* This function should not be called by application code hence the\r
1837                 'Restricted' in its name.  It is not part of the public API.  It is\r
1838                 designed for use by kernel code, and has special calling requirements.\r
1839                 It can result in vListInsert() being called on a list that can only\r
1840                 possibly ever have one item in it, so the list will be fast, but even\r
1841                 so it should be called with the scheduler locked and not from a critical\r
1842                 section. */\r
1843 \r
1844                 /* Only do anything if there are no messages in the queue.  This function\r
1845                 will not actually cause the task to block, just place it on a blocked\r
1846                 list.  It will not block until the scheduler is unlocked - at which\r
1847                 time a yield will be performed.  If an item is added to the queue while\r
1848                 the queue is locked, and the calling task blocks on the queue, then the\r
1849                 calling task will be immediately unblocked when the queue is unlocked. */\r
1850                 prvLockQueue( pxQueue );\r
1851                 if( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0U )\r
1852                 {\r
1853                         /* There is nothing in the queue, block for the specified period. */\r
1854                         vTaskPlaceOnEventListRestricted( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );\r
1855                 }\r
1856                 prvUnlockQueue( pxQueue );\r
1857         }\r
1858 \r
1859 #endif /* configUSE_TIMERS */\r
1860 /*-----------------------------------------------------------*/\r
1861 \r
1862 #if ( configUSE_QUEUE_SETS == 1 )\r
1863 \r
1864         xQueueSetHandle xQueueCreateSet( unsigned portBASE_TYPE uxEventQueueLength )\r
1865         {\r
1866         xQueueSetHandle pxQueue;\r
1867 \r
1868                 pxQueue = xQueueGenericCreate( uxEventQueueLength, sizeof( xQUEUE * ), queueQUEUE_TYPE_SET );\r
1869 \r
1870                 return pxQueue;\r
1871         }\r
1872 \r
1873 #endif /* configUSE_QUEUE_SETS */\r
1874 /*-----------------------------------------------------------*/\r
1875 \r
1876 #if ( configUSE_QUEUE_SETS == 1 )\r
1877 \r
1878         portBASE_TYPE xQueueAddToSet( xQueueSetMemberHandle xQueueOrSemaphore, xQueueSetHandle xQueueSet )\r
1879         {\r
1880         portBASE_TYPE xReturn;\r
1881 \r
1882                 if( ( ( xQUEUE * ) xQueueOrSemaphore )->pxQueueSetContainer != NULL )\r
1883                 {\r
1884                         /* Cannot add a queue/semaphore to more than one queue set. */\r
1885                         xReturn = pdFAIL;\r
1886                 }\r
1887                 else if( ( ( xQUEUE * ) xQueueOrSemaphore )->uxMessagesWaiting != 0 )\r
1888                 {\r
1889                         /* Cannot add a queue/semaphore to a queue set if there are already\r
1890                         items in the queue/semaphore. */\r
1891                         xReturn = pdFAIL;\r
1892                 }\r
1893                 else\r
1894                 {\r
1895                         taskENTER_CRITICAL();\r
1896                         {\r
1897                                 ( ( xQUEUE * ) xQueueOrSemaphore )->pxQueueSetContainer = xQueueSet;\r
1898                         }\r
1899                         taskEXIT_CRITICAL();\r
1900                         xReturn = pdPASS;\r
1901                 }\r
1902 \r
1903                 return xReturn;\r
1904         }\r
1905 \r
1906 #endif /* configUSE_QUEUE_SETS */\r
1907 /*-----------------------------------------------------------*/\r
1908 \r
1909 #if ( configUSE_QUEUE_SETS == 1 )\r
1910 \r
1911         portBASE_TYPE xQueueRemoveFromSet( xQueueSetMemberHandle xQueueOrSemaphore, xQueueSetHandle xQueueSet )\r
1912         {\r
1913         portBASE_TYPE xReturn;\r
1914         xQUEUE *pxQueueOrSemaphore;\r
1915 \r
1916                 pxQueueOrSemaphore = ( xQUEUE * ) xQueueOrSemaphore;\r
1917 \r
1918                 if( pxQueueOrSemaphore->pxQueueSetContainer != xQueueSet )\r
1919                 {\r
1920                         /* The queue was not a member of the set. */\r
1921                         xReturn = pdFAIL;\r
1922                 }\r
1923                 else if( pxQueueOrSemaphore->uxMessagesWaiting != 0 )\r
1924                 {\r
1925                         /* It is dangerous to remove a queue from a set when the queue is\r
1926                         not empty because the queue set will still hold pending events for\r
1927                         the queue. */\r
1928                         xReturn = pdFAIL;\r
1929                 }\r
1930                 else\r
1931                 {\r
1932                         taskENTER_CRITICAL();\r
1933                         {\r
1934                                 /* The queue is no longer contained in the set. */\r
1935                                 pxQueueOrSemaphore->pxQueueSetContainer = NULL;\r
1936                         }\r
1937                         taskEXIT_CRITICAL();\r
1938                         xReturn = pdPASS;\r
1939                 }\r
1940 \r
1941                 return xReturn;\r
1942         }\r
1943 \r
1944 #endif /* configUSE_QUEUE_SETS */\r
1945 /*-----------------------------------------------------------*/\r
1946 \r
1947 #if ( configUSE_QUEUE_SETS == 1 )\r
1948 \r
1949         xQueueSetMemberHandle xQueueSelectFromSet( xQueueSetHandle xQueueSet, portTickType xBlockTimeTicks )\r
1950         {\r
1951         xQueueSetMemberHandle xReturn = NULL;\r
1952 \r
1953                 xQueueGenericReceive( ( xQueueHandle ) xQueueSet, &xReturn, xBlockTimeTicks, pdFALSE );\r
1954                 return xReturn;\r
1955         }\r
1956 \r
1957 #endif /* configUSE_QUEUE_SETS */\r
1958 /*-----------------------------------------------------------*/\r
1959 \r
1960 #if ( configUSE_QUEUE_SETS == 1 )\r
1961 \r
1962         xQueueSetMemberHandle xQueueSelectFromSetFromISR( xQueueSetHandle xQueueSet )\r
1963         {\r
1964         xQueueSetMemberHandle xReturn = NULL;\r
1965 \r
1966                 xQueueReceiveFromISR( ( xQueueHandle ) xQueueSet, &xReturn, NULL );\r
1967                 return xReturn;\r
1968         }\r
1969 \r
1970 #endif /* configUSE_QUEUE_SETS */\r
1971 /*-----------------------------------------------------------*/\r
1972 \r
1973 #if ( configUSE_QUEUE_SETS == 1 )\r
1974 \r
1975         static portBASE_TYPE prvNotifyQueueSetContainer( xQUEUE *pxQueue, portBASE_TYPE xCopyPosition )\r
1976         {\r
1977         xQUEUE *pxQueueSetContainer = pxQueue->pxQueueSetContainer;\r
1978         portBASE_TYPE xReturn = pdFALSE;\r
1979 \r
1980                 configASSERT( pxQueueSetContainer );\r
1981                 configASSERT( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength );\r
1982 \r
1983                 if( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength )\r
1984                 {\r
1985                         traceQUEUE_SEND( pxQueueSetContainer );\r
1986                         /* The data copies is the handle of the queue that contains data. */\r
1987                         prvCopyDataToQueue( pxQueueSetContainer, &pxQueue, xCopyPosition );\r
1988                         if( listLIST_IS_EMPTY( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) == pdFALSE )\r
1989                         {\r
1990                                 if( xTaskRemoveFromEventList( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) != pdFALSE )\r
1991                                 {\r
1992                                         /* The task waiting has a higher priority */\r
1993                                         xReturn = pdTRUE;\r
1994                                 }\r
1995                         }\r
1996                 }\r
1997 \r
1998                 return xReturn;\r
1999         }\r
2000 \r
2001 #endif /* configUSE_QUEUE_SETS */\r
2002 \r