1 /* 2 * FreeRTOS Kernel V11.1.0 3 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. 4 * 5 * SPDX-License-Identifier: MIT 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy of 8 * this software and associated documentation files (the "Software"), to deal in 9 * the Software without restriction, including without limitation the rights to 10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of 11 * the Software, and to permit persons to whom the Software is furnished to do so, 12 * subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in all 15 * copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS 19 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR 20 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER 21 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23 * 24 * https://www.FreeRTOS.org 25 * https://github.com/FreeRTOS 26 * 27 */ 28 29 /* 30 * This is the list implementation used by the scheduler. While it is tailored 31 * heavily for the schedulers needs, it is also available for use by 32 * application code. 33 * 34 * list_ts can only store pointers to list_item_ts. Each ListItem_t contains a 35 * numeric value (xItemValue). Most of the time the lists are sorted in 36 * ascending item value order. 37 * 38 * Lists are created already containing one list item. The value of this 39 * item is the maximum possible that can be stored, it is therefore always at 40 * the end of the list and acts as a marker. The list member pxHead always 41 * points to this marker - even though it is at the tail of the list. This 42 * is because the tail contains a wrap back pointer to the true head of 43 * the list. 44 * 45 * In addition to it's value, each list item contains a pointer to the next 46 * item in the list (pxNext), a pointer to the list it is in (pxContainer) 47 * and a pointer to back to the object that contains it. These later two 48 * pointers are included for efficiency of list manipulation. There is 49 * effectively a two way link between the object containing the list item and 50 * the list item itself. 51 * 52 * 53 * \page ListIntroduction List Implementation 54 * \ingroup FreeRTOSIntro 55 */ 56 57 58 #ifndef LIST_H 59 #define LIST_H 60 61 #ifndef INC_FREERTOS_H 62 #error "FreeRTOS.h must be included before list.h" 63 #endif 64 65 /* 66 * The list structure members are modified from within interrupts, and therefore 67 * by rights should be declared volatile. However, they are only modified in a 68 * functionally atomic way (within critical sections of with the scheduler 69 * suspended) and are either passed by reference into a function or indexed via 70 * a volatile variable. Therefore, in all use cases tested so far, the volatile 71 * qualifier can be omitted in order to provide a moderate performance 72 * improvement without adversely affecting functional behaviour. The assembly 73 * instructions generated by the IAR, ARM and GCC compilers when the respective 74 * compiler's options were set for maximum optimisation has been inspected and 75 * deemed to be as intended. That said, as compiler technology advances, and 76 * especially if aggressive cross module optimisation is used (a use case that 77 * has not been exercised to any great extend) then it is feasible that the 78 * volatile qualifier will be needed for correct optimisation. It is expected 79 * that a compiler removing essential code because, without the volatile 80 * qualifier on the list structure members and with aggressive cross module 81 * optimisation, the compiler deemed the code unnecessary will result in 82 * complete and obvious failure of the scheduler. If this is ever experienced 83 * then the volatile qualifier can be inserted in the relevant places within the 84 * list structures by simply defining configLIST_VOLATILE to volatile in 85 * FreeRTOSConfig.h (as per the example at the bottom of this comment block). 86 * If configLIST_VOLATILE is not defined then the preprocessor directives below 87 * will simply #define configLIST_VOLATILE away completely. 88 * 89 * To use volatile list structure members then add the following line to 90 * FreeRTOSConfig.h (without the quotes): 91 * "#define configLIST_VOLATILE volatile" 92 */ 93 #ifndef configLIST_VOLATILE 94 #define configLIST_VOLATILE 95 #endif /* configSUPPORT_CROSS_MODULE_OPTIMISATION */ 96 97 /* *INDENT-OFF* */ 98 #ifdef __cplusplus 99 extern "C" { 100 #endif 101 /* *INDENT-ON* */ 102 103 /* Macros that can be used to place known values within the list structures, 104 * then check that the known values do not get corrupted during the execution of 105 * the application. These may catch the list data structures being overwritten in 106 * memory. They will not catch data errors caused by incorrect configuration or 107 * use of FreeRTOS.*/ 108 #if ( configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES == 0 ) 109 /* Define the macros to do nothing. */ 110 #define listFIRST_LIST_ITEM_INTEGRITY_CHECK_VALUE 111 #define listSECOND_LIST_ITEM_INTEGRITY_CHECK_VALUE 112 #define listFIRST_LIST_INTEGRITY_CHECK_VALUE 113 #define listSECOND_LIST_INTEGRITY_CHECK_VALUE 114 #define listSET_FIRST_LIST_ITEM_INTEGRITY_CHECK_VALUE( pxItem ) 115 #define listSET_SECOND_LIST_ITEM_INTEGRITY_CHECK_VALUE( pxItem ) 116 #define listSET_LIST_INTEGRITY_CHECK_1_VALUE( pxList ) 117 #define listSET_LIST_INTEGRITY_CHECK_2_VALUE( pxList ) 118 #define listTEST_LIST_ITEM_INTEGRITY( pxItem ) 119 #define listTEST_LIST_INTEGRITY( pxList ) 120 #else /* if ( configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES == 0 ) */ 121 /* Define macros that add new members into the list structures. */ 122 #define listFIRST_LIST_ITEM_INTEGRITY_CHECK_VALUE TickType_t xListItemIntegrityValue1; 123 #define listSECOND_LIST_ITEM_INTEGRITY_CHECK_VALUE TickType_t xListItemIntegrityValue2; 124 #define listFIRST_LIST_INTEGRITY_CHECK_VALUE TickType_t xListIntegrityValue1; 125 #define listSECOND_LIST_INTEGRITY_CHECK_VALUE TickType_t xListIntegrityValue2; 126 127 /* Define macros that set the new structure members to known values. */ 128 #define listSET_FIRST_LIST_ITEM_INTEGRITY_CHECK_VALUE( pxItem ) ( pxItem )->xListItemIntegrityValue1 = pdINTEGRITY_CHECK_VALUE 129 #define listSET_SECOND_LIST_ITEM_INTEGRITY_CHECK_VALUE( pxItem ) ( pxItem )->xListItemIntegrityValue2 = pdINTEGRITY_CHECK_VALUE 130 #define listSET_LIST_INTEGRITY_CHECK_1_VALUE( pxList ) ( pxList )->xListIntegrityValue1 = pdINTEGRITY_CHECK_VALUE 131 #define listSET_LIST_INTEGRITY_CHECK_2_VALUE( pxList ) ( pxList )->xListIntegrityValue2 = pdINTEGRITY_CHECK_VALUE 132 133 /* Define macros that will assert if one of the structure members does not 134 * contain its expected value. */ 135 #define listTEST_LIST_ITEM_INTEGRITY( pxItem ) configASSERT( ( ( pxItem )->xListItemIntegrityValue1 == pdINTEGRITY_CHECK_VALUE ) && ( ( pxItem )->xListItemIntegrityValue2 == pdINTEGRITY_CHECK_VALUE ) ) 136 #define listTEST_LIST_INTEGRITY( pxList ) configASSERT( ( ( pxList )->xListIntegrityValue1 == pdINTEGRITY_CHECK_VALUE ) && ( ( pxList )->xListIntegrityValue2 == pdINTEGRITY_CHECK_VALUE ) ) 137 #endif /* configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES */ 138 139 140 /* 141 * Definition of the only type of object that a list can contain. 142 */ 143 struct xLIST; 144 struct xLIST_ITEM 145 { 146 listFIRST_LIST_ITEM_INTEGRITY_CHECK_VALUE /**< Set to a known value if configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES is set to 1. */ 147 configLIST_VOLATILE TickType_t xItemValue; /**< The value being listed. In most cases this is used to sort the list in ascending order. */ 148 struct xLIST_ITEM * configLIST_VOLATILE pxNext; /**< Pointer to the next ListItem_t in the list. */ 149 struct xLIST_ITEM * configLIST_VOLATILE pxPrevious; /**< Pointer to the previous ListItem_t in the list. */ 150 void * pvOwner; /**< Pointer to the object (normally a TCB) that contains the list item. There is therefore a two way link between the object containing the list item and the list item itself. */ 151 struct xLIST * configLIST_VOLATILE pxContainer; /**< Pointer to the list in which this list item is placed (if any). */ 152 listSECOND_LIST_ITEM_INTEGRITY_CHECK_VALUE /**< Set to a known value if configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES is set to 1. */ 153 }; 154 typedef struct xLIST_ITEM ListItem_t; 155 156 #if ( configUSE_MINI_LIST_ITEM == 1 ) 157 struct xMINI_LIST_ITEM 158 { 159 listFIRST_LIST_ITEM_INTEGRITY_CHECK_VALUE /**< Set to a known value if configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES is set to 1. */ 160 configLIST_VOLATILE TickType_t xItemValue; 161 struct xLIST_ITEM * configLIST_VOLATILE pxNext; 162 struct xLIST_ITEM * configLIST_VOLATILE pxPrevious; 163 }; 164 typedef struct xMINI_LIST_ITEM MiniListItem_t; 165 #else 166 typedef struct xLIST_ITEM MiniListItem_t; 167 #endif 168 169 /* 170 * Definition of the type of queue used by the scheduler. 171 */ 172 typedef struct xLIST 173 { 174 listFIRST_LIST_INTEGRITY_CHECK_VALUE /**< Set to a known value if configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES is set to 1. */ 175 configLIST_VOLATILE UBaseType_t uxNumberOfItems; 176 ListItem_t * configLIST_VOLATILE pxIndex; /**< Used to walk through the list. Points to the last item returned by a call to listGET_OWNER_OF_NEXT_ENTRY (). */ 177 MiniListItem_t xListEnd; /**< List item that contains the maximum possible item value meaning it is always at the end of the list and is therefore used as a marker. */ 178 listSECOND_LIST_INTEGRITY_CHECK_VALUE /**< Set to a known value if configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES is set to 1. */ 179 } List_t; 180 181 /* 182 * Access macro to set the owner of a list item. The owner of a list item 183 * is the object (usually a TCB) that contains the list item. 184 * 185 * \page listSET_LIST_ITEM_OWNER listSET_LIST_ITEM_OWNER 186 * \ingroup LinkedList 187 */ 188 #define listSET_LIST_ITEM_OWNER( pxListItem, pxOwner ) ( ( pxListItem )->pvOwner = ( void * ) ( pxOwner ) ) 189 190 /* 191 * Access macro to get the owner of a list item. The owner of a list item 192 * is the object (usually a TCB) that contains the list item. 193 * 194 * \page listGET_LIST_ITEM_OWNER listSET_LIST_ITEM_OWNER 195 * \ingroup LinkedList 196 */ 197 #define listGET_LIST_ITEM_OWNER( pxListItem ) ( ( pxListItem )->pvOwner ) 198 199 /* 200 * Access macro to set the value of the list item. In most cases the value is 201 * used to sort the list in ascending order. 202 * 203 * \page listSET_LIST_ITEM_VALUE listSET_LIST_ITEM_VALUE 204 * \ingroup LinkedList 205 */ 206 #define listSET_LIST_ITEM_VALUE( pxListItem, xValue ) ( ( pxListItem )->xItemValue = ( xValue ) ) 207 208 /* 209 * Access macro to retrieve the value of the list item. The value can 210 * represent anything - for example the priority of a task, or the time at 211 * which a task should be unblocked. 212 * 213 * \page listGET_LIST_ITEM_VALUE listGET_LIST_ITEM_VALUE 214 * \ingroup LinkedList 215 */ 216 #define listGET_LIST_ITEM_VALUE( pxListItem ) ( ( pxListItem )->xItemValue ) 217 218 /* 219 * Access macro to retrieve the value of the list item at the head of a given 220 * list. 221 * 222 * \page listGET_LIST_ITEM_VALUE listGET_LIST_ITEM_VALUE 223 * \ingroup LinkedList 224 */ 225 #define listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxList ) ( ( ( pxList )->xListEnd ).pxNext->xItemValue ) 226 227 /* 228 * Return the list item at the head of the list. 229 * 230 * \page listGET_HEAD_ENTRY listGET_HEAD_ENTRY 231 * \ingroup LinkedList 232 */ 233 #define listGET_HEAD_ENTRY( pxList ) ( ( ( pxList )->xListEnd ).pxNext ) 234 235 /* 236 * Return the next list item. 237 * 238 * \page listGET_NEXT listGET_NEXT 239 * \ingroup LinkedList 240 */ 241 #define listGET_NEXT( pxListItem ) ( ( pxListItem )->pxNext ) 242 243 /* 244 * Return the list item that marks the end of the list 245 * 246 * \page listGET_END_MARKER listGET_END_MARKER 247 * \ingroup LinkedList 248 */ 249 #define listGET_END_MARKER( pxList ) ( ( ListItem_t const * ) ( &( ( pxList )->xListEnd ) ) ) 250 251 /* 252 * Access macro to determine if a list contains any items. The macro will 253 * only have the value true if the list is empty. 254 * 255 * \page listLIST_IS_EMPTY listLIST_IS_EMPTY 256 * \ingroup LinkedList 257 */ 258 #define listLIST_IS_EMPTY( pxList ) ( ( ( pxList )->uxNumberOfItems == ( UBaseType_t ) 0 ) ? pdTRUE : pdFALSE ) 259 260 /* 261 * Access macro to return the number of items in the list. 262 */ 263 #define listCURRENT_LIST_LENGTH( pxList ) ( ( pxList )->uxNumberOfItems ) 264 265 /* 266 * Access function to obtain the owner of the next entry in a list. 267 * 268 * The list member pxIndex is used to walk through a list. Calling 269 * listGET_OWNER_OF_NEXT_ENTRY increments pxIndex to the next item in the list 270 * and returns that entry's pxOwner parameter. Using multiple calls to this 271 * function it is therefore possible to move through every item contained in 272 * a list. 273 * 274 * The pxOwner parameter of a list item is a pointer to the object that owns 275 * the list item. In the scheduler this is normally a task control block. 276 * The pxOwner parameter effectively creates a two way link between the list 277 * item and its owner. 278 * 279 * @param pxTCB pxTCB is set to the address of the owner of the next list item. 280 * @param pxList The list from which the next item owner is to be returned. 281 * 282 * \page listGET_OWNER_OF_NEXT_ENTRY listGET_OWNER_OF_NEXT_ENTRY 283 * \ingroup LinkedList 284 */ 285 #if ( configNUMBER_OF_CORES == 1 ) 286 #define listGET_OWNER_OF_NEXT_ENTRY( pxTCB, pxList ) \ 287 do { \ 288 List_t * const pxConstList = ( pxList ); \ 289 /* Increment the index to the next item and return the item, ensuring */ \ 290 /* we don't return the marker used at the end of the list. */ \ 291 ( pxConstList )->pxIndex = ( pxConstList )->pxIndex->pxNext; \ 292 if( ( void * ) ( pxConstList )->pxIndex == ( void * ) &( ( pxConstList )->xListEnd ) ) \ 293 { \ 294 ( pxConstList )->pxIndex = ( pxConstList )->xListEnd.pxNext; \ 295 } \ 296 ( pxTCB ) = ( pxConstList )->pxIndex->pvOwner; \ 297 } while( 0 ) 298 #else /* #if ( configNUMBER_OF_CORES == 1 ) */ 299 300 /* This function is not required in SMP. FreeRTOS SMP scheduler doesn't use 301 * pxIndex and it should always point to the xListEnd. Not defining this macro 302 * here to prevent updating pxIndex. 303 */ 304 #endif /* #if ( configNUMBER_OF_CORES == 1 ) */ 305 306 /* 307 * Version of uxListRemove() that does not return a value. Provided as a slight 308 * optimisation for xTaskIncrementTick() by being inline. 309 * 310 * Remove an item from a list. The list item has a pointer to the list that 311 * it is in, so only the list item need be passed into the function. 312 * 313 * @param uxListRemove The item to be removed. The item will remove itself from 314 * the list pointed to by it's pxContainer parameter. 315 * 316 * @return The number of items that remain in the list after the list item has 317 * been removed. 318 * 319 * \page listREMOVE_ITEM listREMOVE_ITEM 320 * \ingroup LinkedList 321 */ 322 #define listREMOVE_ITEM( pxItemToRemove ) \ 323 do { \ 324 /* The list item knows which list it is in. Obtain the list from the list \ 325 * item. */ \ 326 List_t * const pxList = ( pxItemToRemove )->pxContainer; \ 327 \ 328 ( pxItemToRemove )->pxNext->pxPrevious = ( pxItemToRemove )->pxPrevious; \ 329 ( pxItemToRemove )->pxPrevious->pxNext = ( pxItemToRemove )->pxNext; \ 330 /* Make sure the index is left pointing to a valid item. */ \ 331 if( pxList->pxIndex == ( pxItemToRemove ) ) \ 332 { \ 333 pxList->pxIndex = ( pxItemToRemove )->pxPrevious; \ 334 } \ 335 \ 336 ( pxItemToRemove )->pxContainer = NULL; \ 337 ( ( pxList )->uxNumberOfItems ) = ( UBaseType_t ) ( ( ( pxList )->uxNumberOfItems ) - 1U ); \ 338 } while( 0 ) 339 340 /* 341 * Inline version of vListInsertEnd() to provide slight optimisation for 342 * xTaskIncrementTick(). 343 * 344 * Insert a list item into a list. The item will be inserted in a position 345 * such that it will be the last item within the list returned by multiple 346 * calls to listGET_OWNER_OF_NEXT_ENTRY. 347 * 348 * The list member pxIndex is used to walk through a list. Calling 349 * listGET_OWNER_OF_NEXT_ENTRY increments pxIndex to the next item in the list. 350 * Placing an item in a list using vListInsertEnd effectively places the item 351 * in the list position pointed to by pxIndex. This means that every other 352 * item within the list will be returned by listGET_OWNER_OF_NEXT_ENTRY before 353 * the pxIndex parameter again points to the item being inserted. 354 * 355 * @param pxList The list into which the item is to be inserted. 356 * 357 * @param pxNewListItem The list item to be inserted into the list. 358 * 359 * \page listINSERT_END listINSERT_END 360 * \ingroup LinkedList 361 */ 362 #define listINSERT_END( pxList, pxNewListItem ) \ 363 do { \ 364 ListItem_t * const pxIndex = ( pxList )->pxIndex; \ 365 \ 366 /* Only effective when configASSERT() is also defined, these tests may catch \ 367 * the list data structures being overwritten in memory. They will not catch \ 368 * data errors caused by incorrect configuration or use of FreeRTOS. */ \ 369 listTEST_LIST_INTEGRITY( ( pxList ) ); \ 370 listTEST_LIST_ITEM_INTEGRITY( ( pxNewListItem ) ); \ 371 \ 372 /* Insert a new list item into ( pxList ), but rather than sort the list, \ 373 * makes the new list item the last item to be removed by a call to \ 374 * listGET_OWNER_OF_NEXT_ENTRY(). */ \ 375 ( pxNewListItem )->pxNext = pxIndex; \ 376 ( pxNewListItem )->pxPrevious = pxIndex->pxPrevious; \ 377 \ 378 pxIndex->pxPrevious->pxNext = ( pxNewListItem ); \ 379 pxIndex->pxPrevious = ( pxNewListItem ); \ 380 \ 381 /* Remember which list the item is in. */ \ 382 ( pxNewListItem )->pxContainer = ( pxList ); \ 383 \ 384 ( ( pxList )->uxNumberOfItems ) = ( UBaseType_t ) ( ( ( pxList )->uxNumberOfItems ) + 1U ); \ 385 } while( 0 ) 386 387 /* 388 * Access function to obtain the owner of the first entry in a list. Lists 389 * are normally sorted in ascending item value order. 390 * 391 * This function returns the pxOwner member of the first item in the list. 392 * The pxOwner parameter of a list item is a pointer to the object that owns 393 * the list item. In the scheduler this is normally a task control block. 394 * The pxOwner parameter effectively creates a two way link between the list 395 * item and its owner. 396 * 397 * @param pxList The list from which the owner of the head item is to be 398 * returned. 399 * 400 * \page listGET_OWNER_OF_HEAD_ENTRY listGET_OWNER_OF_HEAD_ENTRY 401 * \ingroup LinkedList 402 */ 403 #define listGET_OWNER_OF_HEAD_ENTRY( pxList ) ( ( &( ( pxList )->xListEnd ) )->pxNext->pvOwner ) 404 405 /* 406 * Check to see if a list item is within a list. The list item maintains a 407 * "container" pointer that points to the list it is in. All this macro does 408 * is check to see if the container and the list match. 409 * 410 * @param pxList The list we want to know if the list item is within. 411 * @param pxListItem The list item we want to know if is in the list. 412 * @return pdTRUE if the list item is in the list, otherwise pdFALSE. 413 */ 414 #define listIS_CONTAINED_WITHIN( pxList, pxListItem ) ( ( ( pxListItem )->pxContainer == ( pxList ) ) ? ( pdTRUE ) : ( pdFALSE ) ) 415 416 /* 417 * Return the list a list item is contained within (referenced from). 418 * 419 * @param pxListItem The list item being queried. 420 * @return A pointer to the List_t object that references the pxListItem 421 */ 422 #define listLIST_ITEM_CONTAINER( pxListItem ) ( ( pxListItem )->pxContainer ) 423 424 /* 425 * This provides a crude means of knowing if a list has been initialised, as 426 * pxList->xListEnd.xItemValue is set to portMAX_DELAY by the vListInitialise() 427 * function. 428 */ 429 #define listLIST_IS_INITIALISED( pxList ) ( ( pxList )->xListEnd.xItemValue == portMAX_DELAY ) 430 431 /* 432 * Must be called before a list is used! This initialises all the members 433 * of the list structure and inserts the xListEnd item into the list as a 434 * marker to the back of the list. 435 * 436 * @param pxList Pointer to the list being initialised. 437 * 438 * \page vListInitialise vListInitialise 439 * \ingroup LinkedList 440 */ 441 void vListInitialise( List_t * const pxList ) PRIVILEGED_FUNCTION; 442 443 /* 444 * Must be called before a list item is used. This sets the list container to 445 * null so the item does not think that it is already contained in a list. 446 * 447 * @param pxItem Pointer to the list item being initialised. 448 * 449 * \page vListInitialiseItem vListInitialiseItem 450 * \ingroup LinkedList 451 */ 452 void vListInitialiseItem( ListItem_t * const pxItem ) PRIVILEGED_FUNCTION; 453 454 /* 455 * Insert a list item into a list. The item will be inserted into the list in 456 * a position determined by its item value (ascending item value order). 457 * 458 * @param pxList The list into which the item is to be inserted. 459 * 460 * @param pxNewListItem The item that is to be placed in the list. 461 * 462 * \page vListInsert vListInsert 463 * \ingroup LinkedList 464 */ 465 void vListInsert( List_t * const pxList, 466 ListItem_t * const pxNewListItem ) PRIVILEGED_FUNCTION; 467 468 /* 469 * Insert a list item into a list. The item will be inserted in a position 470 * such that it will be the last item within the list returned by multiple 471 * calls to listGET_OWNER_OF_NEXT_ENTRY. 472 * 473 * The list member pxIndex is used to walk through a list. Calling 474 * listGET_OWNER_OF_NEXT_ENTRY increments pxIndex to the next item in the list. 475 * Placing an item in a list using vListInsertEnd effectively places the item 476 * in the list position pointed to by pxIndex. This means that every other 477 * item within the list will be returned by listGET_OWNER_OF_NEXT_ENTRY before 478 * the pxIndex parameter again points to the item being inserted. 479 * 480 * @param pxList The list into which the item is to be inserted. 481 * 482 * @param pxNewListItem The list item to be inserted into the list. 483 * 484 * \page vListInsertEnd vListInsertEnd 485 * \ingroup LinkedList 486 */ 487 void vListInsertEnd( List_t * const pxList, 488 ListItem_t * const pxNewListItem ) PRIVILEGED_FUNCTION; 489 490 /* 491 * Remove an item from a list. The list item has a pointer to the list that 492 * it is in, so only the list item need be passed into the function. 493 * 494 * @param uxListRemove The item to be removed. The item will remove itself from 495 * the list pointed to by it's pxContainer parameter. 496 * 497 * @return The number of items that remain in the list after the list item has 498 * been removed. 499 * 500 * \page uxListRemove uxListRemove 501 * \ingroup LinkedList 502 */ 503 UBaseType_t uxListRemove( ListItem_t * const pxItemToRemove ) PRIVILEGED_FUNCTION; 504 505 /* *INDENT-OFF* */ 506 #ifdef __cplusplus 507 } 508 #endif 509 /* *INDENT-ON* */ 510 511 #endif /* ifndef LIST_H */ 512