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 1992-2013, Micrium, Weston, FL
  8. * All Rights Reserved
  9. *
  10. * File : OS_MBOX.C
  11. * By : Jean J. Labrosse
  12. * Version : V2.92.11
  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 Micrium 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. #define MICRIUM_SOURCE
  24. #ifndef OS_MASTER_FILE
  25. #include <ucos_ii.h>
  26. #endif
  27. #if OS_MBOX_EN > 0u
  28. /*
  29. *********************************************************************************************************
  30. * ACCEPT MESSAGE FROM MAILBOX
  31. *
  32. * Description: This function checks the mailbox to see if a message is available. Unlike OSMboxPend(),
  33. * OSMboxAccept() does not suspend the calling task if a message is not available.
  34. *
  35. * Arguments : pevent is a pointer to the event control block
  36. *
  37. * Returns : != (void *)0 is the message in the mailbox if one is available. The mailbox is cleared
  38. * so the next time OSMboxAccept() is called, the mailbox will be empty.
  39. * == (void *)0 if the mailbox is empty or,
  40. * if 'pevent' is a NULL pointer or,
  41. * if you didn't pass the proper event pointer.
  42. *********************************************************************************************************
  43. */
  44. #if OS_MBOX_ACCEPT_EN > 0u
  45. void *OSMboxAccept (OS_EVENT *pevent)
  46. {
  47. void *pmsg;
  48. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  49. OS_CPU_SR cpu_sr = 0u;
  50. #endif
  51. #if OS_ARG_CHK_EN > 0u
  52. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  53. return ((void *)0);
  54. }
  55. #endif
  56. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  57. return ((void *)0);
  58. }
  59. OS_ENTER_CRITICAL();
  60. pmsg = pevent->OSEventPtr;
  61. pevent->OSEventPtr = (void *)0; /* Clear the mailbox */
  62. OS_EXIT_CRITICAL();
  63. return (pmsg); /* Return the message received (or NULL) */
  64. }
  65. #endif
  66. /*$PAGE*/
  67. /*
  68. *********************************************************************************************************
  69. * CREATE A MESSAGE MAILBOX
  70. *
  71. * Description: This function creates a message mailbox if free event control blocks are available.
  72. *
  73. * Arguments : pmsg is a pointer to a message that you wish to deposit in the mailbox. If
  74. * you set this value to the NULL pointer (i.e. (void *)0) then the mailbox
  75. * will be considered empty.
  76. *
  77. * Returns : != (OS_EVENT *)0 is a pointer to the event control clock (OS_EVENT) associated with the
  78. * created mailbox
  79. * == (OS_EVENT *)0 if no event control blocks were available
  80. *********************************************************************************************************
  81. */
  82. OS_EVENT *OSMboxCreate (void *pmsg)
  83. {
  84. OS_EVENT *pevent;
  85. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  86. OS_CPU_SR cpu_sr = 0u;
  87. #endif
  88. #ifdef OS_SAFETY_CRITICAL_IEC61508
  89. if (OSSafetyCriticalStartFlag == OS_TRUE) {
  90. OS_SAFETY_CRITICAL_EXCEPTION();
  91. return ((OS_EVENT *)0);
  92. }
  93. #endif
  94. if (OSIntNesting > 0u) { /* See if called from ISR ... */
  95. return ((OS_EVENT *)0); /* ... can't CREATE from an ISR */
  96. }
  97. OS_ENTER_CRITICAL();
  98. pevent = OSEventFreeList; /* Get next free event control block */
  99. if (OSEventFreeList != (OS_EVENT *)0) { /* See if pool of free ECB pool was empty */
  100. OSEventFreeList = (OS_EVENT *)OSEventFreeList->OSEventPtr;
  101. }
  102. OS_EXIT_CRITICAL();
  103. if (pevent != (OS_EVENT *)0) {
  104. pevent->OSEventType = OS_EVENT_TYPE_MBOX;
  105. pevent->OSEventCnt = 0u;
  106. pevent->OSEventPtr = pmsg; /* Deposit message in event control block */
  107. #if OS_EVENT_NAME_EN > 0u
  108. pevent->OSEventName = (INT8U *)(void *)"?";
  109. #endif
  110. OS_EventWaitListInit(pevent);
  111. }
  112. return (pevent); /* Return pointer to event control block */
  113. }
  114. /*$PAGE*/
  115. /*
  116. *********************************************************************************************************
  117. * DELETE A MAIBOX
  118. *
  119. * Description: This function deletes a mailbox and readies all tasks pending on the mailbox.
  120. *
  121. * Arguments : pevent is a pointer to the event control block associated with the desired
  122. * mailbox.
  123. *
  124. * opt determines delete options as follows:
  125. * opt == OS_DEL_NO_PEND Delete the mailbox ONLY if no task pending
  126. * opt == OS_DEL_ALWAYS Deletes the mailbox even if tasks are waiting.
  127. * In this case, all the tasks pending will be readied.
  128. *
  129. * perr is a pointer to an error code that can contain one of the following values:
  130. * OS_ERR_NONE The call was successful and the mailbox was deleted
  131. * OS_ERR_DEL_ISR If you attempted to delete the mailbox from an ISR
  132. * OS_ERR_INVALID_OPT An invalid option was specified
  133. * OS_ERR_TASK_WAITING One or more tasks were waiting on the mailbox
  134. * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a mailbox
  135. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
  136. *
  137. * Returns : pevent upon error
  138. * (OS_EVENT *)0 if the mailbox was successfully deleted.
  139. *
  140. * Note(s) : 1) This function must be used with care. Tasks that would normally expect the presence of
  141. * the mailbox MUST check the return code of OSMboxPend().
  142. * 2) OSMboxAccept() callers will not know that the intended mailbox has been deleted!
  143. * 3) This call can potentially disable interrupts for a long time. The interrupt disable
  144. * time is directly proportional to the number of tasks waiting on the mailbox.
  145. * 4) Because ALL tasks pending on the mailbox will be readied, you MUST be careful in
  146. * applications where the mailbox is used for mutual exclusion because the resource(s)
  147. * will no longer be guarded by the mailbox.
  148. * 5) All tasks that were waiting for the mailbox will be readied and returned an
  149. * OS_ERR_PEND_ABORT if OSMboxDel() was called with OS_DEL_ALWAYS
  150. *********************************************************************************************************
  151. */
  152. #if OS_MBOX_DEL_EN > 0u
  153. OS_EVENT *OSMboxDel (OS_EVENT *pevent,
  154. INT8U opt,
  155. INT8U *perr)
  156. {
  157. BOOLEAN tasks_waiting;
  158. OS_EVENT *pevent_return;
  159. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  160. OS_CPU_SR cpu_sr = 0u;
  161. #endif
  162. #ifdef OS_SAFETY_CRITICAL
  163. if (perr == (INT8U *)0) {
  164. OS_SAFETY_CRITICAL_EXCEPTION();
  165. return ((OS_EVENT *)0);
  166. }
  167. #endif
  168. #if OS_ARG_CHK_EN > 0u
  169. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  170. *perr = OS_ERR_PEVENT_NULL;
  171. return (pevent);
  172. }
  173. #endif
  174. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  175. *perr = OS_ERR_EVENT_TYPE;
  176. return (pevent);
  177. }
  178. if (OSIntNesting > 0u) { /* See if called from ISR ... */
  179. *perr = OS_ERR_DEL_ISR; /* ... can't DELETE from an ISR */
  180. return (pevent);
  181. }
  182. OS_ENTER_CRITICAL();
  183. if (pevent->OSEventGrp != 0u) { /* See if any tasks waiting on mailbox */
  184. tasks_waiting = OS_TRUE; /* Yes */
  185. } else {
  186. tasks_waiting = OS_FALSE; /* No */
  187. }
  188. switch (opt) {
  189. case OS_DEL_NO_PEND: /* Delete mailbox only if no task waiting */
  190. if (tasks_waiting == OS_FALSE) {
  191. #if OS_EVENT_NAME_EN > 0u
  192. pevent->OSEventName = (INT8U *)(void *)"?";
  193. #endif
  194. pevent->OSEventType = OS_EVENT_TYPE_UNUSED;
  195. pevent->OSEventPtr = OSEventFreeList; /* Return Event Control Block to free list */
  196. pevent->OSEventCnt = 0u;
  197. OSEventFreeList = pevent; /* Get next free event control block */
  198. OS_EXIT_CRITICAL();
  199. *perr = OS_ERR_NONE;
  200. pevent_return = (OS_EVENT *)0; /* Mailbox has been deleted */
  201. } else {
  202. OS_EXIT_CRITICAL();
  203. *perr = OS_ERR_TASK_WAITING;
  204. pevent_return = pevent;
  205. }
  206. break;
  207. case OS_DEL_ALWAYS: /* Always delete the mailbox */
  208. while (pevent->OSEventGrp != 0u) { /* Ready ALL tasks waiting for mailbox */
  209. (void)OS_EventTaskRdy(pevent, (void *)0, OS_STAT_MBOX, OS_STAT_PEND_ABORT);
  210. }
  211. #if OS_EVENT_NAME_EN > 0u
  212. pevent->OSEventName = (INT8U *)(void *)"?";
  213. #endif
  214. pevent->OSEventType = OS_EVENT_TYPE_UNUSED;
  215. pevent->OSEventPtr = OSEventFreeList; /* Return Event Control Block to free list */
  216. pevent->OSEventCnt = 0u;
  217. OSEventFreeList = pevent; /* Get next free event control block */
  218. OS_EXIT_CRITICAL();
  219. if (tasks_waiting == OS_TRUE) { /* Reschedule only if task(s) were waiting */
  220. OS_Sched(); /* Find highest priority task ready to run */
  221. }
  222. *perr = OS_ERR_NONE;
  223. pevent_return = (OS_EVENT *)0; /* Mailbox has been deleted */
  224. break;
  225. default:
  226. OS_EXIT_CRITICAL();
  227. *perr = OS_ERR_INVALID_OPT;
  228. pevent_return = pevent;
  229. break;
  230. }
  231. return (pevent_return);
  232. }
  233. #endif
  234. /*$PAGE*/
  235. /*
  236. *********************************************************************************************************
  237. * PEND ON MAILBOX FOR A MESSAGE
  238. *
  239. * Description: This function waits for a message to be sent to a mailbox
  240. *
  241. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  242. *
  243. * timeout is an optional timeout period (in clock ticks). If non-zero, your task will
  244. * wait for a message to arrive at the mailbox up to the amount of time
  245. * specified by this argument. If you specify 0, however, your task will wait
  246. * forever at the specified mailbox or, until a message arrives.
  247. *
  248. * perr is a pointer to where an error message will be deposited. Possible error
  249. * messages are:
  250. *
  251. * OS_ERR_NONE The call was successful and your task received a
  252. * message.
  253. * OS_ERR_TIMEOUT A message was not received within the specified 'timeout'.
  254. * OS_ERR_PEND_ABORT The wait on the mailbox was aborted.
  255. * OS_ERR_EVENT_TYPE Invalid event type
  256. * OS_ERR_PEND_ISR If you called this function from an ISR and the result
  257. * would lead to a suspension.
  258. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  259. * OS_ERR_PEND_LOCKED If you called this function when the scheduler is locked
  260. *
  261. * Returns : != (void *)0 is a pointer to the message received
  262. * == (void *)0 if no message was received or,
  263. * if 'pevent' is a NULL pointer or,
  264. * if you didn't pass the proper pointer to the event control block.
  265. *********************************************************************************************************
  266. */
  267. /*$PAGE*/
  268. void *OSMboxPend (OS_EVENT *pevent,
  269. INT32U timeout,
  270. INT8U *perr)
  271. {
  272. void *pmsg;
  273. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  274. OS_CPU_SR cpu_sr = 0u;
  275. #endif
  276. #ifdef OS_SAFETY_CRITICAL
  277. if (perr == (INT8U *)0) {
  278. OS_SAFETY_CRITICAL_EXCEPTION();
  279. return ((void *)0);
  280. }
  281. #endif
  282. #if OS_ARG_CHK_EN > 0u
  283. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  284. *perr = OS_ERR_PEVENT_NULL;
  285. return ((void *)0);
  286. }
  287. #endif
  288. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  289. *perr = OS_ERR_EVENT_TYPE;
  290. return ((void *)0);
  291. }
  292. if (OSIntNesting > 0u) { /* See if called from ISR ... */
  293. *perr = OS_ERR_PEND_ISR; /* ... can't PEND from an ISR */
  294. return ((void *)0);
  295. }
  296. if (OSLockNesting > 0u) { /* See if called with scheduler locked ... */
  297. *perr = OS_ERR_PEND_LOCKED; /* ... can't PEND when locked */
  298. return ((void *)0);
  299. }
  300. OS_ENTER_CRITICAL();
  301. pmsg = pevent->OSEventPtr;
  302. if (pmsg != (void *)0) { /* See if there is already a message */
  303. pevent->OSEventPtr = (void *)0; /* Clear the mailbox */
  304. OS_EXIT_CRITICAL();
  305. *perr = OS_ERR_NONE;
  306. return (pmsg); /* Return the message received (or NULL) */
  307. }
  308. OSTCBCur->OSTCBStat |= OS_STAT_MBOX; /* Message not available, task will pend */
  309. OSTCBCur->OSTCBStatPend = OS_STAT_PEND_OK;
  310. OSTCBCur->OSTCBDly = timeout; /* Load timeout in TCB */
  311. OS_EventTaskWait(pevent); /* Suspend task until event or timeout occurs */
  312. OS_EXIT_CRITICAL();
  313. OS_Sched(); /* Find next highest priority task ready to run */
  314. OS_ENTER_CRITICAL();
  315. switch (OSTCBCur->OSTCBStatPend) { /* See if we timed-out or aborted */
  316. case OS_STAT_PEND_OK:
  317. pmsg = OSTCBCur->OSTCBMsg;
  318. *perr = OS_ERR_NONE;
  319. break;
  320. case OS_STAT_PEND_ABORT:
  321. pmsg = (void *)0;
  322. *perr = OS_ERR_PEND_ABORT; /* Indicate that we aborted */
  323. break;
  324. case OS_STAT_PEND_TO:
  325. default:
  326. OS_EventTaskRemove(OSTCBCur, pevent);
  327. pmsg = (void *)0;
  328. *perr = OS_ERR_TIMEOUT; /* Indicate that we didn't get event within TO */
  329. break;
  330. }
  331. OSTCBCur->OSTCBStat = OS_STAT_RDY; /* Set task status to ready */
  332. OSTCBCur->OSTCBStatPend = OS_STAT_PEND_OK; /* Clear pend status */
  333. OSTCBCur->OSTCBEventPtr = (OS_EVENT *)0; /* Clear event pointers */
  334. #if (OS_EVENT_MULTI_EN > 0u)
  335. OSTCBCur->OSTCBEventMultiPtr = (OS_EVENT **)0;
  336. #endif
  337. OSTCBCur->OSTCBMsg = (void *)0; /* Clear received message */
  338. OS_EXIT_CRITICAL();
  339. return (pmsg); /* Return received message */
  340. }
  341. /*$PAGE*/
  342. /*
  343. *********************************************************************************************************
  344. * ABORT WAITING ON A MESSAGE MAILBOX
  345. *
  346. * Description: This function aborts & readies any tasks currently waiting on a mailbox. This function
  347. * should be used to fault-abort the wait on the mailbox, rather than to normally signal
  348. * the mailbox via OSMboxPost() or OSMboxPostOpt().
  349. *
  350. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox.
  351. *
  352. * opt determines the type of ABORT performed:
  353. * OS_PEND_OPT_NONE ABORT wait for a single task (HPT) waiting on the
  354. * mailbox
  355. * OS_PEND_OPT_BROADCAST ABORT wait for ALL tasks that are waiting on the
  356. * mailbox
  357. *
  358. * perr is a pointer to where an error message will be deposited. Possible error
  359. * messages are:
  360. *
  361. * OS_ERR_NONE No tasks were waiting on the mailbox.
  362. * OS_ERR_PEND_ABORT At least one task waiting on the mailbox was readied
  363. * and informed of the aborted wait; check return value
  364. * for the number of tasks whose wait on the mailbox
  365. * was aborted.
  366. * OS_ERR_EVENT_TYPE If you didn't pass a pointer to a mailbox.
  367. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer.
  368. *
  369. * Returns : == 0 if no tasks were waiting on the mailbox, or upon error.
  370. * > 0 if one or more tasks waiting on the mailbox are now readied and informed.
  371. *********************************************************************************************************
  372. */
  373. #if OS_MBOX_PEND_ABORT_EN > 0u
  374. INT8U OSMboxPendAbort (OS_EVENT *pevent,
  375. INT8U opt,
  376. INT8U *perr)
  377. {
  378. INT8U nbr_tasks;
  379. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  380. OS_CPU_SR cpu_sr = 0u;
  381. #endif
  382. #ifdef OS_SAFETY_CRITICAL
  383. if (perr == (INT8U *)0) {
  384. OS_SAFETY_CRITICAL_EXCEPTION();
  385. return (0u);
  386. }
  387. #endif
  388. #if OS_ARG_CHK_EN > 0u
  389. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  390. *perr = OS_ERR_PEVENT_NULL;
  391. return (0u);
  392. }
  393. #endif
  394. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  395. *perr = OS_ERR_EVENT_TYPE;
  396. return (0u);
  397. }
  398. OS_ENTER_CRITICAL();
  399. if (pevent->OSEventGrp != 0u) { /* See if any task waiting on mailbox? */
  400. nbr_tasks = 0u;
  401. switch (opt) {
  402. case OS_PEND_OPT_BROADCAST: /* Do we need to abort ALL waiting tasks? */
  403. while (pevent->OSEventGrp != 0u) { /* Yes, ready ALL tasks waiting on mailbox */
  404. (void)OS_EventTaskRdy(pevent, (void *)0, OS_STAT_MBOX, OS_STAT_PEND_ABORT);
  405. nbr_tasks++;
  406. }
  407. break;
  408. case OS_PEND_OPT_NONE:
  409. default: /* No, ready HPT waiting on mailbox */
  410. (void)OS_EventTaskRdy(pevent, (void *)0, OS_STAT_MBOX, OS_STAT_PEND_ABORT);
  411. nbr_tasks++;
  412. break;
  413. }
  414. OS_EXIT_CRITICAL();
  415. OS_Sched(); /* Find HPT ready to run */
  416. *perr = OS_ERR_PEND_ABORT;
  417. return (nbr_tasks);
  418. }
  419. OS_EXIT_CRITICAL();
  420. *perr = OS_ERR_NONE;
  421. return (0u); /* No tasks waiting on mailbox */
  422. }
  423. #endif
  424. /*$PAGE*/
  425. /*
  426. *********************************************************************************************************
  427. * POST MESSAGE TO A MAILBOX
  428. *
  429. * Description: This function sends a message to a mailbox
  430. *
  431. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  432. *
  433. * pmsg is a pointer to the message to send. You MUST NOT send a NULL pointer.
  434. *
  435. * Returns : OS_ERR_NONE The call was successful and the message was sent
  436. * OS_ERR_MBOX_FULL If the mailbox already contains a message. You can can only send one
  437. * message at a time and thus, the message MUST be consumed before you
  438. * are allowed to send another one.
  439. * OS_ERR_EVENT_TYPE If you are attempting to post to a non mailbox.
  440. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  441. * OS_ERR_POST_NULL_PTR If you are attempting to post a NULL pointer
  442. *
  443. * Note(s) : 1) HPT means Highest Priority Task
  444. *********************************************************************************************************
  445. */
  446. #if OS_MBOX_POST_EN > 0u
  447. INT8U OSMboxPost (OS_EVENT *pevent,
  448. void *pmsg)
  449. {
  450. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  451. OS_CPU_SR cpu_sr = 0u;
  452. #endif
  453. #if OS_ARG_CHK_EN > 0u
  454. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  455. return (OS_ERR_PEVENT_NULL);
  456. }
  457. if (pmsg == (void *)0) { /* Make sure we are not posting a NULL pointer */
  458. return (OS_ERR_POST_NULL_PTR);
  459. }
  460. #endif
  461. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  462. return (OS_ERR_EVENT_TYPE);
  463. }
  464. OS_ENTER_CRITICAL();
  465. if (pevent->OSEventGrp != 0u) { /* See if any task pending on mailbox */
  466. /* Ready HPT waiting on event */
  467. (void)OS_EventTaskRdy(pevent, pmsg, OS_STAT_MBOX, OS_STAT_PEND_OK);
  468. OS_EXIT_CRITICAL();
  469. OS_Sched(); /* Find highest priority task ready to run */
  470. return (OS_ERR_NONE);
  471. }
  472. if (pevent->OSEventPtr != (void *)0) { /* Make sure mailbox doesn't already have a msg */
  473. OS_EXIT_CRITICAL();
  474. return (OS_ERR_MBOX_FULL);
  475. }
  476. pevent->OSEventPtr = pmsg; /* Place message in mailbox */
  477. OS_EXIT_CRITICAL();
  478. return (OS_ERR_NONE);
  479. }
  480. #endif
  481. /*$PAGE*/
  482. /*
  483. *********************************************************************************************************
  484. * POST MESSAGE TO A MAILBOX
  485. *
  486. * Description: This function sends a message to a mailbox
  487. *
  488. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  489. *
  490. * pmsg is a pointer to the message to send. You MUST NOT send a NULL pointer.
  491. *
  492. * opt determines the type of POST performed:
  493. * OS_POST_OPT_NONE POST to a single waiting task
  494. * (Identical to OSMboxPost())
  495. * OS_POST_OPT_BROADCAST POST to ALL tasks that are waiting on the mailbox
  496. *
  497. * OS_POST_OPT_NO_SCHED Indicates that the scheduler will NOT be invoked
  498. *
  499. * Returns : OS_ERR_NONE The call was successful and the message was sent
  500. * OS_ERR_MBOX_FULL If the mailbox already contains a message. You can can only send one
  501. * message at a time and thus, the message MUST be consumed before you
  502. * are allowed to send another one.
  503. * OS_ERR_EVENT_TYPE If you are attempting to post to a non mailbox.
  504. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  505. * OS_ERR_POST_NULL_PTR If you are attempting to post a NULL pointer
  506. *
  507. * Note(s) : 1) HPT means Highest Priority Task
  508. *
  509. * Warning : Interrupts can be disabled for a long time if you do a 'broadcast'. In fact, the
  510. * interrupt disable time is proportional to the number of tasks waiting on the mailbox.
  511. *********************************************************************************************************
  512. */
  513. #if OS_MBOX_POST_OPT_EN > 0u
  514. INT8U OSMboxPostOpt (OS_EVENT *pevent,
  515. void *pmsg,
  516. INT8U opt)
  517. {
  518. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  519. OS_CPU_SR cpu_sr = 0u;
  520. #endif
  521. #if OS_ARG_CHK_EN > 0u
  522. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  523. return (OS_ERR_PEVENT_NULL);
  524. }
  525. if (pmsg == (void *)0) { /* Make sure we are not posting a NULL pointer */
  526. return (OS_ERR_POST_NULL_PTR);
  527. }
  528. #endif
  529. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  530. return (OS_ERR_EVENT_TYPE);
  531. }
  532. OS_ENTER_CRITICAL();
  533. if (pevent->OSEventGrp != 0u) { /* See if any task pending on mailbox */
  534. if ((opt & OS_POST_OPT_BROADCAST) != 0x00u) { /* Do we need to post msg to ALL waiting tasks ? */
  535. while (pevent->OSEventGrp != 0u) { /* Yes, Post to ALL tasks waiting on mailbox */
  536. (void)OS_EventTaskRdy(pevent, pmsg, OS_STAT_MBOX, OS_STAT_PEND_OK);
  537. }
  538. } else { /* No, Post to HPT waiting on mbox */
  539. (void)OS_EventTaskRdy(pevent, pmsg, OS_STAT_MBOX, OS_STAT_PEND_OK);
  540. }
  541. OS_EXIT_CRITICAL();
  542. if ((opt & OS_POST_OPT_NO_SCHED) == 0u) { /* See if scheduler needs to be invoked */
  543. OS_Sched(); /* Find HPT ready to run */
  544. }
  545. return (OS_ERR_NONE);
  546. }
  547. if (pevent->OSEventPtr != (void *)0) { /* Make sure mailbox doesn't already have a msg */
  548. OS_EXIT_CRITICAL();
  549. return (OS_ERR_MBOX_FULL);
  550. }
  551. pevent->OSEventPtr = pmsg; /* Place message in mailbox */
  552. OS_EXIT_CRITICAL();
  553. return (OS_ERR_NONE);
  554. }
  555. #endif
  556. /*$PAGE*/
  557. /*
  558. *********************************************************************************************************
  559. * QUERY A MESSAGE MAILBOX
  560. *
  561. * Description: This function obtains information about a message mailbox.
  562. *
  563. * Arguments : pevent is a pointer to the event control block associated with the desired mailbox
  564. *
  565. * p_mbox_data is a pointer to a structure that will contain information about the message
  566. * mailbox.
  567. *
  568. * Returns : OS_ERR_NONE The call was successful and the message was sent
  569. * OS_ERR_EVENT_TYPE If you are attempting to obtain data from a non mailbox.
  570. * OS_ERR_PEVENT_NULL If 'pevent' is a NULL pointer
  571. * OS_ERR_PDATA_NULL If 'p_mbox_data' is a NULL pointer
  572. *********************************************************************************************************
  573. */
  574. #if OS_MBOX_QUERY_EN > 0u
  575. INT8U OSMboxQuery (OS_EVENT *pevent,
  576. OS_MBOX_DATA *p_mbox_data)
  577. {
  578. INT8U i;
  579. OS_PRIO *psrc;
  580. OS_PRIO *pdest;
  581. #if OS_CRITICAL_METHOD == 3u /* Allocate storage for CPU status register */
  582. OS_CPU_SR cpu_sr = 0u;
  583. #endif
  584. #if OS_ARG_CHK_EN > 0u
  585. if (pevent == (OS_EVENT *)0) { /* Validate 'pevent' */
  586. return (OS_ERR_PEVENT_NULL);
  587. }
  588. if (p_mbox_data == (OS_MBOX_DATA *)0) { /* Validate 'p_mbox_data' */
  589. return (OS_ERR_PDATA_NULL);
  590. }
  591. #endif
  592. if (pevent->OSEventType != OS_EVENT_TYPE_MBOX) { /* Validate event block type */
  593. return (OS_ERR_EVENT_TYPE);
  594. }
  595. OS_ENTER_CRITICAL();
  596. p_mbox_data->OSEventGrp = pevent->OSEventGrp; /* Copy message mailbox wait list */
  597. psrc = &pevent->OSEventTbl[0];
  598. pdest = &p_mbox_data->OSEventTbl[0];
  599. for (i = 0u; i < OS_EVENT_TBL_SIZE; i++) {
  600. *pdest++ = *psrc++;
  601. }
  602. p_mbox_data->OSMsg = pevent->OSEventPtr; /* Get message from mailbox */
  603. OS_EXIT_CRITICAL();
  604. return (OS_ERR_NONE);
  605. }
  606. #endif /* OS_MBOX_QUERY_EN */
  607. #endif /* OS_MBOX_EN */