list.h 24 KB

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