📄 os_flag.lst
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223 /*
224 *********************************************************************************************************
225 * DELETE AN EVENT FLAG GROUP
226 *
227 * Description: This function deletes an event flag group and readies all tasks pending on the event flag
228 * group.
229 *
230 * Arguments : pgrp is a pointer to the desired event flag group.
231 *
232 * opt determines delete options as follows:
233 * opt == OS_DEL_NO_PEND Deletes the event flag group ONLY if no task pending
234 * opt == OS_DEL_ALWAYS Deletes the event flag group even if tasks are
235 * waiting. In this case, all the tasks pending will be
236 * readied.
237 *
238 * err is a pointer to an error code that can contain one of the following values:
239 * OS_NO_ERR The call was successful and the event flag group was
240 * deleted
C51 COMPILER V6.23a OS_FLAG 12/09/2004 16:50:25 PAGE 5
241 * OS_ERR_DEL_ISR If you attempted to delete the event flag group from
242 * an ISR
243 * OS_FLAG_INVALID_PGRP If 'pgrp' is a NULL pointer.
244 * OS_ERR_EVENT_TYPE If you didn't pass a pointer to an event flag group
245 * OS_ERR_INVALID_OPT An invalid option was specified
246 * OS_ERR_TASK_WAITING One or more tasks were waiting on the event flag
247 * group.
248 *
249 * Returns : pevent upon error
250 * (OS_EVENT *)0 if the semaphore was successfully deleted.
251 *
252 * Note(s) : 1) This function must be used with care. Tasks that would normally expect the presence of
253 * the event flag group MUST check the return code of OSFlagAccept() and OSFlagPend().
254 * 2) This call can potentially disable interrupts for a long time. The interrupt disable
255 * time is directly proportional to the number of tasks waiting on the event flag group.
256 *********************************************************************************************************
257 */
258
259 #if OS_FLAG_DEL_EN > 0
260 OS_FLAG_GRP *OSFlagDel (OS_FLAG_GRP *pgrp, INT8U opt, INT8U *err) KCREENTRANT
261 {
262 1 #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
265 1 BOOLEAN tasks_waiting;
266 1 OS_FLAG_NODE *pnode;
267 1
268 1
269 1 if (OSIntNesting > 0) { /* See if called from ISR ... */
270 2 *err = OS_ERR_DEL_ISR; /* ... can't DELETE from an ISR */
271 2 return (pgrp);
272 2 }
273 1 #if OS_ARG_CHK_EN > 0
274 1 if (pgrp == (OS_FLAG_GRP *)0) { /* Validate 'pgrp' */
275 2 *err = OS_FLAG_INVALID_PGRP;
276 2 return (pgrp);
277 2 }
278 1 if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) { /* Validate event group type */
279 2 *err = OS_ERR_EVENT_TYPE;
280 2 return (pgrp);
281 2 }
282 1 #endif
283 1 OS_ENTER_CRITICAL();
284 1 if (pgrp->OSFlagWaitList != (void *)0) { /* See if any tasks waiting on event flags */
285 2 tasks_waiting = TRUE; /* Yes */
286 2 } else {
287 2 tasks_waiting = FALSE; /* No */
288 2 }
289 1 switch (opt) {
290 2 case OS_DEL_NO_PEND: /* Delete group if no task waiting */
291 2 if (tasks_waiting == FALSE) {
292 3 pgrp->OSFlagType = OS_EVENT_TYPE_UNUSED;
293 3 pgrp->OSFlagWaitList = (void *)OSFlagFreeList; /* Return group to free list */
294 3 OSFlagFreeList = pgrp;
295 3 OS_EXIT_CRITICAL();
296 3 *err = OS_NO_ERR;
297 3 return ((OS_FLAG_GRP *)0); /* Event Flag Group has been deleted */
298 3 } else {
299 3 OS_EXIT_CRITICAL();
300 3 *err = OS_ERR_TASK_WAITING;
301 3 return (pgrp);
302 3 }
C51 COMPILER V6.23a OS_FLAG 12/09/2004 16:50:25 PAGE 6
303 2
304 2 case OS_DEL_ALWAYS: /* Always delete the event flag group */
305 2 pnode = (OS_FLAG_NODE *)pgrp->OSFlagWaitList;
306 2 while (pnode != (OS_FLAG_NODE *)0) { /* Ready ALL tasks waiting for flags */
307 3 OS_FlagTaskRdy(pnode, (OS_FLAGS)0);
308 3 pnode = (OS_FLAG_NODE *)pnode->OSFlagNodeNext;
309 3 }
310 2 pgrp->OSFlagType = OS_EVENT_TYPE_UNUSED;
311 2 pgrp->OSFlagWaitList = (void *)OSFlagFreeList;/* Return group to free list */
312 2 OSFlagFreeList = pgrp;
313 2 OS_EXIT_CRITICAL();
314 2 if (tasks_waiting == TRUE) { /* Reschedule only if task(s) were waiting */
315 3 OS_Sched(); /* Find highest priority task ready to run */
316 3 }
317 2 *err = OS_NO_ERR;
318 2 return ((OS_FLAG_GRP *)0); /* Event Flag Group has been deleted */
319 2
320 2 default:
321 2 OS_EXIT_CRITICAL();
322 2 *err = OS_ERR_INVALID_OPT;
323 2 return (pgrp);
324 2 }
325 1 }
326 #endif
327 /*$PAGE*/
328 /*
329 *********************************************************************************************************
330 * WAIT ON AN EVENT FLAG GROUP
331 *
332 * Description: This function is called to wait for a combination of bits to be set in an event flag
333 * group. Your application can wait for ANY bit to be set or ALL bits to be set.
334 *
335 * Arguments : pgrp is a pointer to the desired event flag group.
336 *
337 * flags Is a bit pattern indicating which bit(s) (i.e. flags) you wish to wait for.
338 * The bits you want are specified by setting the corresponding bits in
339 * 'flags'. e.g. if your application wants to wait for bits 0 and 1 then
340 * 'flags' would contain 0x03.
341 *
342 * wait_type specifies whether you want ALL bits to be set or ANY of the bits to be set.
343 * You can specify the following argument:
344 *
345 * OS_FLAG_WAIT_CLR_ALL You will wait for ALL bits in 'mask' to be clear (0)
346 * OS_FLAG_WAIT_SET_ALL You will wait for ALL bits in 'mask' to be set (1)
347 * OS_FLAG_WAIT_CLR_ANY You will wait for ANY bit in 'mask' to be clear (0)
348 * OS_FLAG_WAIT_SET_ANY You will wait for ANY bit in 'mask' to be set (1)
349 *
350 * NOTE: Add OS_FLAG_CONSUME if you want the event flag to be 'consumed' by
351 * the call. Example, to wait for any flag in a group AND then clear
352 * the flags that are present, set 'wait_type' to:
353 *
354 * OS_FLAG_WAIT_SET_ANY + OS_FLAG_CONSUME
355 *
356 * timeout is an optional timeout (in clock ticks) that your task will wait for the
357 * desired bit combination. If you specify 0, however, your task will wait
358 * forever at the specified event flag group or, until a message arrives.
359 *
360 * err is a pointer to an error code and can be:
361 * OS_NO_ERR The desired bits have been set within the specified
362 * 'timeout'.
363 * OS_ERR_PEND_ISR If you tried to PEND from an ISR
364 * OS_FLAG_INVALID_PGRP If 'pgrp' is a NULL pointer.
C51 COMPILER V6.23a OS_FLAG 12/09/2004 16:50:25 PAGE 7
365 * OS_ERR_EVENT_TYPE You are not pointing to an event flag group
366 * OS_TIMEOUT The bit(s) have not been set in the specified
367 * 'timeout'.
368 * OS_FLAG_ERR_WAIT_TYPE You didn't specify a proper 'wait_type' argument.
369 *
370 * Returns : The new state of the flags in the event flag group when the task is resumed or,
371 * 0 if a timeout or an error occurred.
372 *
373 * Called from: Task ONLY
374 *********************************************************************************************************
375 */
376
377 OS_FLAGS OSFlagPend (OS_FLAG_GRP *pgrp, OS_FLAGS flags, INT8U wait_type, INT16U timeout, INT8U *err) KCRE
-ENTRANT
378 {
379 1 #if OS_CRITICAL_METHOD == 3 /* Allocate storage for CPU status register */
OS_CPU_SR cpu_sr;
#endif
382 1 OS_FLAG_NODE node;
383 1 OS_FLAGS flags_cur;
384 1 OS_FLAGS flags_rdy;
385 1 BOOLEAN consume;
386 1
387 1
388 1 if (OSIntNesting > 0) { /* See if called from ISR ... */
389 2 *err = OS_ERR_PEND_ISR; /* ... can't PEND from an ISR */
390 2 return ((OS_FLAGS)0);
391 2 }
392 1 #if OS_ARG_CHK_EN > 0
393 1 if (pgrp == (OS_FLAG_GRP *)0) { /* Validate 'pgrp' */
394 2 *err = OS_FLAG_INVALID_PGRP;
395 2 return ((OS_FLAGS)0);
396 2 }
397 1 if (pgrp->OSFlagType != OS_EVENT_TYPE_FLAG) { /* Validate event block type */
398 2 *err = OS_ERR_EVENT_TYPE;
399 2 return ((OS_FLAGS)0);
400 2 }
401 1 #endif
402 1 if (wait_type & OS_FLAG_CONSUME) { /* See if we need to consume the flags */
403 2 wait_type &= ~OS_FLAG_CONSUME;
404 2 consume = TRUE;
405 2 } else {
406 2 consume = FALSE;
407 2 }
408 1 /*$PAGE*/
409 1 OS_ENTER_CRITICAL();
410 1 switch (wait_type) {
411 2 case OS_FLAG_WAIT_SET_ALL: /* See if all required flags are set */
412 2 flags_rdy = pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
413 2 if (flags_rdy == flags) { /* Must match ALL the bits that we want */
414 3 if (consume == TRUE) { /* See if we need to consume the flags */
415 4 pgrp->OSFlagFlags &= ~flags_rdy; /* Clear ONLY the flags that we wanted */
416 4 }
417 3 flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
418 3 OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
419 3 *err = OS_NO_ERR;
420 3 return (flags_cur);
421 3 } else { /* Block task until events occur or timeout */
422 3 OS_FlagBlock(pgrp, &node, flags, wait_type, timeout);
423 3 OS_EXIT_CRITICAL();
424 3 }
425 2 break;
C51 COMPILER V6.23a OS_FLAG 12/09/2004 16:50:25 PAGE 8
426 2
427 2 case OS_FLAG_WAIT_SET_ANY:
428 2 flags_rdy = pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
429 2 if (flags_rdy != (OS_FLAGS)0) { /* See if any flag set */
430 3 if (consume == TRUE) { /* See if we need to consume the flags */
431 4 pgrp->OSFlagFlags &= ~flags_rdy; /* Clear ONLY the flags that we got */
432 4 }
433 3 flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
434 3 OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
435 3 *err = OS_NO_ERR;
436 3 return (flags_cur);
437 3 } else { /* Block task until events occur or timeout */
438 3 OS_FlagBlock(pgrp, &node, flags, wait_type, timeout);
439 3 OS_EXIT_CRITICAL();
440 3 }
441 2 break;
442 2
443 2 #if OS_FLAG_WAIT_CLR_EN > 0
444 2 case OS_FLAG_WAIT_CLR_ALL: /* See if all required flags are cleared */
445 2 flags_rdy = ~pgrp->OSFlagFlags & flags; /* Extract only the bits we want */
446 2 if (flags_rdy == flags) { /* Must match ALL the bits that we want */
447 3 if (consume == TRUE) { /* See if we need to consume the flags */
448 4 pgrp->OSFlagFlags |= flags_rdy; /* Set ONLY the flags that we wanted */
449 4 }
450 3 flags_cur = pgrp->OSFlagFlags; /* Will return the state of the group */
451 3 OS_EXIT_CRITICAL(); /* Yes, condition met, return to caller */
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