os_mbox.c 30 KB

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  1. /*
  2. *********************************************************************************************************
  3. * uC/OS-II
  4. * The Real-Time Kernel
  5. * MESSAGE MAILBOX MANAGEMENT
  6. *
  7. * (c) Copyright 1992-2009, Micrium, Weston, FL
  8. * All Rights Reserved
  9. *
  10. * File : OS_MBOX.C
  11. * By : Jean J. Labrosse
  12. * Version : V2.91
  13. *
  14. * LICENSING TERMS:
  15. * ---------------
  16. * uC/OS-II is provided in source form for FREE evaluation, for educational use or for peaceful research.
  17. * If you plan on using uC/OS-II in a commercial product you need to contact Micriµm to properly license
  18. * its use in your product. We provide ALL the source code for your convenience and to help you experience
  19. * uC/OS-II. The fact that the source is provided does NOT mean that you can use it without paying a
  20. * licensing fee.
  21. *********************************************************************************************************
  22. */
  23. #ifndef OS_MASTER_FILE
  24. #include <ucos_ii.h>
  25. #endif
  26. #if OS_MBOX_EN > 0u
  27. /*
  28. *********************************************************************************************************
  29. * ACCEPT MESSAGE FROM MAILBOX
  30. *
  31. * Description: This function checks the mailbox to see if a message is available. Unlike OSMboxPend(),
  32. * OSMboxAccept() does not suspend the calling task if a message is not available.
  33. *
  34. * Arguments : pevent is a pointer to the event control block
  35. *
  36. * Returns : != (void *)0 is the message in the mailbox if one is available. The mailbox is cleared
  37. * so the next time OSMboxAccept() is called, the mailbox will be empty.
  38. * == (void *)0 if the mailbox is empty or,
  39. * if 'pevent' is a NULL pointer or,
  40. * if you didn't pass the proper event pointer.
  41. *********************************************************************************************************
  42. */
  43. #if OS_MBOX_ACCEPT_EN > 0u
  44. void *OSMboxAccept (OS_EVENT *pevent)
  45. {
  46. void *pmsg;
  47. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  48. OS_CPU_SR cpu_sr = 0u;
  49. #endif
  50. #if OS_ARG_CHK_EN > 0u
  51. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  52. return ((void *)0);
  53. }
  54. #endif
  55. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  56. return ((void *)0);
  57. }
  58. OS_ENTER_CRITICAL();
  59. pmsg = pevent->OSEventPtr;
  60. pevent->OSEventPtr = (void *)0; /* Clear the mailbox */
  61. OS_EXIT_CRITICAL();
  62. return (pmsg); /* Return the message received (or NULL) */
  63. }
  64. #endif
  65. /*$PAGE*/
  66. /*
  67. *********************************************************************************************************
  68. * CREATE A MESSAGE MAILBOX
  69. *
  70. * Description: This function creates a message mailbox if free event control blocks are available.
  71. *
  72. * Arguments : pmsg is a pointer to a message that you wish to deposit in the mailbox. If
  73. * you set this value to the NULL pointer (i.e. (void *)0) then the mailbox
  74. * will be considered empty.
  75. *
  76. * Returns : != (OS_EVENT *)0 is a pointer to the event control clock (OS_EVENT) associated with the
  77. * created mailbox
  78. * == (OS_EVENT *)0 if no event control blocks were available
  79. *********************************************************************************************************
  80. */
  81. OS_EVENT *OSMboxCreate (void *pmsg)
  82. {
  83. OS_EVENT *pevent;
  84. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  85. OS_CPU_SR cpu_sr = 0u;
  86. #endif
  87. #ifdef OS_SAFETY_CRITICAL_IEC61508
  88. if (OSSafetyCriticalStartFlag == OS_TRUE) {
  89. OS_SAFETY_CRITICAL_EXCEPTION();
  90. }
  91. #endif
  92. if (OSIntNesting > 0u) { /* See if called from ISR ... */
  93. return ((OS_EVENT *)0); /* ... can't CREATE from an ISR */
  94. }
  95. OS_ENTER_CRITICAL();
  96. pevent = OSEventFreeList; /* Get next free event control block */
  97. if (OSEventFreeList != (OS_EVENT *)0) { /* See if pool of free ECB pool was empty */
  98. OSEventFreeList = (OS_EVENT *)OSEventFreeList->OSEventPtr;
  99. }
  100. OS_EXIT_CRITICAL();
  101. if (pevent != (OS_EVENT *)0) {
  102. pevent->OSEventType = OS_EVENT_TYPE_MBOX;
  103. pevent->OSEventCnt = 0u;
  104. pevent->OSEventPtr = pmsg; /* Deposit message in event control block */
  105. #if OS_EVENT_NAME_EN > 0u
  106. pevent->OSEventName = (INT8U *)(void *)"?";
  107. #endif
  108. OS_EventWaitListInit(pevent);
  109. }
  110. return (pevent); /* Return pointer to event control block */
  111. }
  112. /*$PAGE*/
  113. /*
  114. *********************************************************************************************************
  115. * DELETE A MAIBOX
  116. *
  117. * Description: This function deletes a mailbox and readies all tasks pending on the mailbox.
  118. *
  119. * Arguments : pevent is a pointer to the event control block associated with the desired
  120. * mailbox.
  121. *
  122. * opt determines delete options as follows:
  123. * opt == OS_DEL_NO_PEND Delete the mailbox ONLY if no task pending
  124. * opt == OS_DEL_ALWAYS Deletes the mailbox even if tasks are waiting.
  125. * In this case, all the tasks pending will be readied.
  126. *
  127. * perr is a pointer to an error code that can contain one of the following values:
  128. * OS_ERR_NONE The call was successful and the mailbox was deleted
  129. * OS_ERR_DEL_ISR If you attempted to delete the mailbox from an ISR
  130. * OS_ERR_INVALID_OPT An invalid option was specified
  131. * OS_ERR_TASK_WAITING One or more tasks were waiting on the mailbox
  132. * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a mailbox
  133. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
  134. *
  135. * Returns : pevent upon error
  136. * (OS_EVENT *)0 if the mailbox was successfully deleted.
  137. *
  138. * Note(s) : 1) This function must be used with care. Tasks that would normally expect the presence of
  139. * the mailbox MUST check the return code of OSMboxPend().
  140. * 2) OSMboxAccept() callers will not know that the intended mailbox has been deleted!
  141. * 3) This call can potentially disable interrupts for a long time. The interrupt disable
  142. * time is directly proportional to the number of tasks waiting on the mailbox.
  143. * 4) Because ALL tasks pending on the mailbox will be readied, you MUST be careful in
  144. * applications where the mailbox is used for mutual exclusion because the resource(s)
  145. * will no longer be guarded by the mailbox.
  146. *********************************************************************************************************
  147. */
  148. #if OS_MBOX_DEL_EN > 0u
  149. OS_EVENT *OSMboxDel (OS_EVENT *pevent,
  150. INT8U opt,
  151. INT8U *perr)
  152. {
  153. BOOLEAN tasks_waiting;
  154. OS_EVENT *pevent_return;
  155. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  156. OS_CPU_SR cpu_sr = 0u;
  157. #endif
  158. #ifdef OS_SAFETY_CRITICAL
  159. if (perr == (INT8U *)0) {
  160. OS_SAFETY_CRITICAL_EXCEPTION();
  161. }
  162. #endif
  163. #if OS_ARG_CHK_EN > 0u
  164. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  165. *perr = OS_ERR_PEVENT_NULL;
  166. return (pevent);
  167. }
  168. #endif
  169. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  170. *perr = OS_ERR_EVENT_TYPE;
  171. return (pevent);
  172. }
  173. if (OSIntNesting > 0u) { /* See if called from ISR ... */
  174. *perr = OS_ERR_DEL_ISR; /* ... can't DELETE from an ISR */
  175. return (pevent);
  176. }
  177. OS_ENTER_CRITICAL();
  178. if (pevent->OSEventGrp != 0u) { /* See if any tasks waiting on mailbox */
  179. tasks_waiting = OS_TRUE; /* Yes */
  180. } else {
  181. tasks_waiting = OS_FALSE; /* No */
  182. }
  183. switch (opt) {
  184. case OS_DEL_NO_PEND: /* Delete mailbox only if no task waiting */
  185. if (tasks_waiting == OS_FALSE) {
  186. #if OS_EVENT_NAME_EN > 0u
  187. pevent->OSEventName = (INT8U *)(void *)"?";
  188. #endif
  189. pevent->OSEventType = OS_EVENT_TYPE_UNUSED;
  190. pevent->OSEventPtr = OSEventFreeList; /* Return Event Control Block to free list */
  191. pevent->OSEventCnt = 0u;
  192. OSEventFreeList = pevent; /* Get next free event control block */
  193. OS_EXIT_CRITICAL();
  194. *perr = OS_ERR_NONE;
  195. pevent_return = (OS_EVENT *)0; /* Mailbox has been deleted */
  196. } else {
  197. OS_EXIT_CRITICAL();
  198. *perr = OS_ERR_TASK_WAITING;
  199. pevent_return = pevent;
  200. }
  201. break;
  202. case OS_DEL_ALWAYS: /* Always delete the mailbox */
  203. while (pevent->OSEventGrp != 0u) { /* Ready ALL tasks waiting for mailbox */
  204. (void)OS_EventTaskRdy(pevent, (void *)0, OS_STAT_MBOX, OS_STAT_PEND_OK);
  205. }
  206. #if OS_EVENT_NAME_EN > 0u
  207. pevent->OSEventName = (INT8U *)(void *)"?";
  208. #endif
  209. pevent->OSEventType = OS_EVENT_TYPE_UNUSED;
  210. pevent->OSEventPtr = OSEventFreeList; /* Return Event Control Block to free list */
  211. pevent->OSEventCnt = 0u;
  212. OSEventFreeList = pevent; /* Get next free event control block */
  213. OS_EXIT_CRITICAL();
  214. if (tasks_waiting == OS_TRUE) { /* Reschedule only if task(s) were waiting */
  215. OS_Sched(); /* Find highest priority task ready to run */
  216. }
  217. *perr = OS_ERR_NONE;
  218. pevent_return = (OS_EVENT *)0; /* Mailbox has been deleted */
  219. break;
  220. default:
  221. OS_EXIT_CRITICAL();
  222. *perr = OS_ERR_INVALID_OPT;
  223. pevent_return = pevent;
  224. break;
  225. }
  226. return (pevent_return);
  227. }
  228. #endif
  229. /*$PAGE*/
  230. /*
  231. *********************************************************************************************************
  232. * PEND ON MAILBOX FOR A MESSAGE
  233. *
  234. * Description: This function waits for a message to be sent to a mailbox
  235. *
  236. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  237. *
  238. * timeout is an optional timeout period (in clock ticks). If non-zero, your task will
  239. * wait for a message to arrive at the mailbox up to the amount of time
  240. * specified by this argument. If you specify 0, however, your task will wait
  241. * forever at the specified mailbox or, until a message arrives.
  242. *
  243. * perr is a pointer to where an error message will be deposited. Possible error
  244. * messages are:
  245. *
  246. * OS_ERR_NONE The call was successful and your task received a
  247. * message.
  248. * OS_ERR_TIMEOUT A message was not received within the specified 'timeout'.
  249. * OS_ERR_PEND_ABORT The wait on the mailbox was aborted.
  250. * OS_ERR_EVENT_TYPE Invalid event type
  251. * OS_ERR_PEND_ISR If you called this function from an ISR and the result
  252. * would lead to a suspension.
  253. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  254. * OS_ERR_PEND_LOCKED If you called this function when the scheduler is locked
  255. *
  256. * Returns : != (void *)0 is a pointer to the message received
  257. * == (void *)0 if no message was received or,
  258. * if 'pevent' is a NULL pointer or,
  259. * if you didn't pass the proper pointer to the event control block.
  260. *********************************************************************************************************
  261. */
  262. /*$PAGE*/
  263. void *OSMboxPend (OS_EVENT *pevent,
  264. INT32U timeout,
  265. INT8U *perr)
  266. {
  267. void *pmsg;
  268. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  269. OS_CPU_SR cpu_sr = 0u;
  270. #endif
  271. #ifdef OS_SAFETY_CRITICAL
  272. if (perr == (INT8U *)0) {
  273. OS_SAFETY_CRITICAL_EXCEPTION();
  274. }
  275. #endif
  276. #if OS_ARG_CHK_EN > 0u
  277. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  278. *perr = OS_ERR_PEVENT_NULL;
  279. return ((void *)0);
  280. }
  281. #endif
  282. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  283. *perr = OS_ERR_EVENT_TYPE;
  284. return ((void *)0);
  285. }
  286. if (OSIntNesting > 0u) { /* See if called from ISR ... */
  287. *perr = OS_ERR_PEND_ISR; /* ... can't PEND from an ISR */
  288. return ((void *)0);
  289. }
  290. if (OSLockNesting > 0u) { /* See if called with scheduler locked ... */
  291. *perr = OS_ERR_PEND_LOCKED; /* ... can't PEND when locked */
  292. return ((void *)0);
  293. }
  294. OS_ENTER_CRITICAL();
  295. pmsg = pevent->OSEventPtr;
  296. if (pmsg != (void *)0) { /* See if there is already a message */
  297. pevent->OSEventPtr = (void *)0; /* Clear the mailbox */
  298. OS_EXIT_CRITICAL();
  299. *perr = OS_ERR_NONE;
  300. return (pmsg); /* Return the message received (or NULL) */
  301. }
  302. OSTCBCur->OSTCBStat |= OS_STAT_MBOX; /* Message not available, task will pend */
  303. OSTCBCur->OSTCBStatPend = OS_STAT_PEND_OK;
  304. OSTCBCur->OSTCBDly = timeout; /* Load timeout in TCB */
  305. OS_EventTaskWait(pevent); /* Suspend task until event or timeout occurs */
  306. OS_EXIT_CRITICAL();
  307. OS_Sched(); /* Find next highest priority task ready to run */
  308. OS_ENTER_CRITICAL();
  309. switch (OSTCBCur->OSTCBStatPend) { /* See if we timed-out or aborted */
  310. case OS_STAT_PEND_OK:
  311. pmsg = OSTCBCur->OSTCBMsg;
  312. *perr = OS_ERR_NONE;
  313. break;
  314. case OS_STAT_PEND_ABORT:
  315. pmsg = (void *)0;
  316. *perr = OS_ERR_PEND_ABORT; /* Indicate that we aborted */
  317. break;
  318. case OS_STAT_PEND_TO:
  319. default:
  320. OS_EventTaskRemove(OSTCBCur, pevent);
  321. pmsg = (void *)0;
  322. *perr = OS_ERR_TIMEOUT; /* Indicate that we didn't get event within TO */
  323. break;
  324. }
  325. OSTCBCur->OSTCBStat = OS_STAT_RDY; /* Set task status to ready */
  326. OSTCBCur->OSTCBStatPend = OS_STAT_PEND_OK; /* Clear pend status */
  327. OSTCBCur->OSTCBEventPtr = (OS_EVENT *)0; /* Clear event pointers */
  328. #if (OS_EVENT_MULTI_EN > 0u)
  329. OSTCBCur->OSTCBEventMultiPtr = (OS_EVENT **)0;
  330. #endif
  331. OSTCBCur->OSTCBMsg = (void *)0; /* Clear received message */
  332. OS_EXIT_CRITICAL();
  333. return (pmsg); /* Return received message */
  334. }
  335. /*$PAGE*/
  336. /*
  337. *********************************************************************************************************
  338. * ABORT WAITING ON A MESSAGE MAILBOX
  339. *
  340. * Description: This function aborts & readies any tasks currently waiting on a mailbox. This function
  341. * should be used to fault-abort the wait on the mailbox, rather than to normally signal
  342. * the mailbox via OSMboxPost() or OSMboxPostOpt().
  343. *
  344. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox.
  345. *
  346. * opt determines the type of ABORT performed:
  347. * OS_PEND_OPT_NONE ABORT wait for a single task (HPT) waiting on the
  348. * mailbox
  349. * OS_PEND_OPT_BROADCAST ABORT wait for ALL tasks that are waiting on the
  350. * mailbox
  351. *
  352. * perr is a pointer to where an error message will be deposited. Possible error
  353. * messages are:
  354. *
  355. * OS_ERR_NONE No tasks were waiting on the mailbox.
  356. * OS_ERR_PEND_ABORT At least one task waiting on the mailbox was readied
  357. * and informed of the aborted wait; check return value
  358. * for the number of tasks whose wait on the mailbox
  359. * was aborted.
  360. * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a mailbox.
  361. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
  362. *
  363. * Returns : == 0 if no tasks were waiting on the mailbox, or upon error.
  364. * > 0 if one or more tasks waiting on the mailbox are now readied and informed.
  365. *********************************************************************************************************
  366. */
  367. #if OS_MBOX_PEND_ABORT_EN > 0u
  368. INT8U OSMboxPendAbort (OS_EVENT *pevent,
  369. INT8U opt,
  370. INT8U *perr)
  371. {
  372. INT8U nbr_tasks;
  373. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  374. OS_CPU_SR cpu_sr = 0u;
  375. #endif
  376. #ifdef OS_SAFETY_CRITICAL
  377. if (perr == (INT8U *)0) {
  378. OS_SAFETY_CRITICAL_EXCEPTION();
  379. }
  380. #endif
  381. #if OS_ARG_CHK_EN > 0u
  382. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  383. *perr = OS_ERR_PEVENT_NULL;
  384. return (0u);
  385. }
  386. #endif
  387. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  388. *perr = OS_ERR_EVENT_TYPE;
  389. return (0u);
  390. }
  391. OS_ENTER_CRITICAL();
  392. if (pevent->OSEventGrp != 0u) { /* See if any task waiting on mailbox? */
  393. nbr_tasks = 0u;
  394. switch (opt) {
  395. case OS_PEND_OPT_BROADCAST: /* Do we need to abort ALL waiting tasks? */
  396. while (pevent->OSEventGrp != 0u) { /* Yes, ready ALL tasks waiting on mailbox */
  397. (void)OS_EventTaskRdy(pevent, (void *)0, OS_STAT_MBOX, OS_STAT_PEND_ABORT);
  398. nbr_tasks++;
  399. }
  400. break;
  401. case OS_PEND_OPT_NONE:
  402. default: /* No, ready HPT waiting on mailbox */
  403. (void)OS_EventTaskRdy(pevent, (void *)0, OS_STAT_MBOX, OS_STAT_PEND_ABORT);
  404. nbr_tasks++;
  405. break;
  406. }
  407. OS_EXIT_CRITICAL();
  408. OS_Sched(); /* Find HPT ready to run */
  409. *perr = OS_ERR_PEND_ABORT;
  410. return (nbr_tasks);
  411. }
  412. OS_EXIT_CRITICAL();
  413. *perr = OS_ERR_NONE;
  414. return (0u); /* No tasks waiting on mailbox */
  415. }
  416. #endif
  417. /*$PAGE*/
  418. /*
  419. *********************************************************************************************************
  420. * POST MESSAGE TO A MAILBOX
  421. *
  422. * Description: This function sends a message to a mailbox
  423. *
  424. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  425. *
  426. * pmsg is a pointer to the message to send. You MUST NOT send a NULL pointer.
  427. *
  428. * Returns : OS_ERR_NONE The call was successful and the message was sent
  429. * OS_ERR_MBOX_FULL If the mailbox already contains a message. You can can only send one
  430. * message at a time and thus, the message MUST be consumed before you
  431. * are allowed to send another one.
  432. * OS_ERR_EVENT_TYPE If you are attempting to post to a non mailbox.
  433. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  434. * OS_ERR_POST_NULL_PTR If you are attempting to post a NULL pointer
  435. *
  436. * Note(s) : 1) HPT means Highest Priority Task
  437. *********************************************************************************************************
  438. */
  439. #if OS_MBOX_POST_EN > 0u
  440. INT8U OSMboxPost (OS_EVENT *pevent,
  441. void *pmsg)
  442. {
  443. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  444. OS_CPU_SR cpu_sr = 0u;
  445. #endif
  446. #if OS_ARG_CHK_EN > 0u
  447. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  448. return (OS_ERR_PEVENT_NULL);
  449. }
  450. if (pmsg == (void *)0) { /* Make sure we are not posting a NULL pointer */
  451. return (OS_ERR_POST_NULL_PTR);
  452. }
  453. #endif
  454. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  455. return (OS_ERR_EVENT_TYPE);
  456. }
  457. OS_ENTER_CRITICAL();
  458. if (pevent->OSEventGrp != 0u) { /* See if any task pending on mailbox */
  459. /* Ready HPT waiting on event */
  460. (void)OS_EventTaskRdy(pevent, pmsg, OS_STAT_MBOX, OS_STAT_PEND_OK);
  461. OS_EXIT_CRITICAL();
  462. OS_Sched(); /* Find highest priority task ready to run */
  463. return (OS_ERR_NONE);
  464. }
  465. if (pevent->OSEventPtr != (void *)0) { /* Make sure mailbox doesn't already have a msg */
  466. OS_EXIT_CRITICAL();
  467. return (OS_ERR_MBOX_FULL);
  468. }
  469. pevent->OSEventPtr = pmsg; /* Place message in mailbox */
  470. OS_EXIT_CRITICAL();
  471. return (OS_ERR_NONE);
  472. }
  473. #endif
  474. /*$PAGE*/
  475. /*
  476. *********************************************************************************************************
  477. * POST MESSAGE TO A MAILBOX
  478. *
  479. * Description: This function sends a message to a mailbox
  480. *
  481. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  482. *
  483. * pmsg is a pointer to the message to send. You MUST NOT send a NULL pointer.
  484. *
  485. * opt determines the type of POST performed:
  486. * OS_POST_OPT_NONE POST to a single waiting task
  487. * (Identical to OSMboxPost())
  488. * OS_POST_OPT_BROADCAST POST to ALL tasks that are waiting on the mailbox
  489. *
  490. * OS_POST_OPT_NO_SCHED Indicates that the scheduler will NOT be invoked
  491. *
  492. * Returns : OS_ERR_NONE The call was successful and the message was sent
  493. * OS_ERR_MBOX_FULL If the mailbox already contains a message. You can can only send one
  494. * message at a time and thus, the message MUST be consumed before you
  495. * are allowed to send another one.
  496. * OS_ERR_EVENT_TYPE If you are attempting to post to a non mailbox.
  497. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  498. * OS_ERR_POST_NULL_PTR If you are attempting to post a NULL pointer
  499. *
  500. * Note(s) : 1) HPT means Highest Priority Task
  501. *
  502. * Warning : Interrupts can be disabled for a long time if you do a 'broadcast'. In fact, the
  503. * interrupt disable time is proportional to the number of tasks waiting on the mailbox.
  504. *********************************************************************************************************
  505. */
  506. #if OS_MBOX_POST_OPT_EN > 0u
  507. INT8U OSMboxPostOpt (OS_EVENT *pevent,
  508. void *pmsg,
  509. INT8U opt)
  510. {
  511. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  512. OS_CPU_SR cpu_sr = 0u;
  513. #endif
  514. #if OS_ARG_CHK_EN > 0u
  515. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  516. return (OS_ERR_PEVENT_NULL);
  517. }
  518. if (pmsg == (void *)0) { /* Make sure we are not posting a NULL pointer */
  519. return (OS_ERR_POST_NULL_PTR);
  520. }
  521. #endif
  522. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  523. return (OS_ERR_EVENT_TYPE);
  524. }
  525. OS_ENTER_CRITICAL();
  526. if (pevent->OSEventGrp != 0u) { /* See if any task pending on mailbox */
  527. if ((opt & OS_POST_OPT_BROADCAST) != 0x00u) { /* Do we need to post msg to ALL waiting tasks ? */
  528. while (pevent->OSEventGrp != 0u) { /* Yes, Post to ALL tasks waiting on mailbox */
  529. (void)OS_EventTaskRdy(pevent, pmsg, OS_STAT_MBOX, OS_STAT_PEND_OK);
  530. }
  531. } else { /* No, Post to HPT waiting on mbox */
  532. (void)OS_EventTaskRdy(pevent, pmsg, OS_STAT_MBOX, OS_STAT_PEND_OK);
  533. }
  534. OS_EXIT_CRITICAL();
  535. if ((opt & OS_POST_OPT_NO_SCHED) == 0u) { /* See if scheduler needs to be invoked */
  536. OS_Sched(); /* Find HPT ready to run */
  537. }
  538. return (OS_ERR_NONE);
  539. }
  540. if (pevent->OSEventPtr != (void *)0) { /* Make sure mailbox doesn't already have a msg */
  541. OS_EXIT_CRITICAL();
  542. return (OS_ERR_MBOX_FULL);
  543. }
  544. pevent->OSEventPtr = pmsg; /* Place message in mailbox */
  545. OS_EXIT_CRITICAL();
  546. return (OS_ERR_NONE);
  547. }
  548. #endif
  549. /*$PAGE*/
  550. /*
  551. *********************************************************************************************************
  552. * QUERY A MESSAGE MAILBOX
  553. *
  554. * Description: This function obtains information about a message mailbox.
  555. *
  556. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  557. *
  558. * p_mbox_data is a pointer to a structure that will contain information about the message
  559. * mailbox.
  560. *
  561. * Returns : OS_ERR_NONE The call was successful and the message was sent
  562. * OS_ERR_EVENT_TYPE If you are attempting to obtain data from a non mailbox.
  563. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  564. * OS_ERR_PDATA_NULL If 'p_mbox_data' is a NULL pointer
  565. *********************************************************************************************************
  566. */
  567. #if OS_MBOX_QUERY_EN > 0u
  568. INT8U OSMboxQuery (OS_EVENT *pevent,
  569. OS_MBOX_DATA *p_mbox_data)
  570. {
  571. INT8U i;
  572. OS_PRIO *psrc;
  573. OS_PRIO *pdest;
  574. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  575. OS_CPU_SR cpu_sr = 0u;
  576. #endif
  577. #if OS_ARG_CHK_EN > 0u
  578. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  579. return (OS_ERR_PEVENT_NULL);
  580. }
  581. if (p_mbox_data == (OS_MBOX_DATA *)0) { /* Validate 'p_mbox_data' */
  582. return (OS_ERR_PDATA_NULL);
  583. }
  584. #endif
  585. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  586. return (OS_ERR_EVENT_TYPE);
  587. }
  588. OS_ENTER_CRITICAL();
  589. p_mbox_data->OSEventGrp = pevent->OSEventGrp; /* Copy message mailbox wait list */
  590. psrc = &pevent->OSEventTbl[0];
  591. pdest = &p_mbox_data->OSEventTbl[0];
  592. for (i = 0u; i < OS_EVENT_TBL_SIZE; i++) {
  593. *pdest++ = *psrc++;
  594. }
  595. p_mbox_data->OSMsg = pevent->OSEventPtr; /* Get message from mailbox */
  596. OS_EXIT_CRITICAL();
  597. return (OS_ERR_NONE);
  598. }
  599. #endif /* OS_MBOX_QUERY_EN */
  600. #endif /* OS_MBOX_EN */