source: rtems/c/src/exec/rtems/src/event.c @ ac7d5ef0

4.104.114.84.95
Last change on this file since ac7d5ef0 was ac7d5ef0, checked in by Joel Sherrill <joel.sherrill@…>, on May 11, 1995 at 5:39:37 PM

Initial revision

  • Property mode set to 100644
File size: 7.1 KB
Line 
1/*
2 *  Event Manager
3 *
4 *  COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
5 *  On-Line Applications Research Corporation (OAR).
6 *  All rights assigned to U.S. Government, 1994.
7 *
8 *  This material may be reproduced by or for the U.S. Government pursuant
9 *  to the copyright license under the clause at DFARS 252.227-7013.  This
10 *  notice must appear in all copies of this file and its derivatives.
11 *
12 *  $Id$
13 */
14
15#include <rtems/system.h>
16#include <rtems/event.h>
17#include <rtems/isr.h>
18#include <rtems/object.h>
19#include <rtems/options.h>
20#include <rtems/states.h>
21#include <rtems/thread.h>
22
23/*PAGE
24 *
25 *  rtems_event_send
26 *
27 *  This directive allows a thread send an event set to another thread.
28 *
29 *  Input parameters:
30 *    id    - thread id
31 *    event - event set
32 *
33 *  Output parameters:
34 *    RTEMS_SUCCESSFUL - if successful
35 *    error code - if unsuccessful
36 */
37
38rtems_status_code rtems_event_send(
39  Objects_Id         id,
40  rtems_event_set event_in
41)
42{
43  register Thread_Control *the_thread;
44  Objects_Locations        location;
45
46  the_thread = _Thread_Get( id, &location );
47  switch ( location ) {
48    case OBJECTS_ERROR:
49      return( RTEMS_INVALID_ID );
50    case OBJECTS_REMOTE:
51      return(
52        _Event_MP_Send_request_packet(
53          EVENT_MP_SEND_REQUEST,
54          id,
55          event_in
56        )
57      );
58    case OBJECTS_LOCAL:
59      _Event_sets_Post( event_in, &the_thread->pending_events );
60      _Event_Surrender( the_thread );
61      _Thread_Enable_dispatch();
62      return( RTEMS_SUCCESSFUL );
63  }
64
65  return( RTEMS_INTERNAL_ERROR );   /* unreached - only to remove warnings */
66}
67
68/*PAGE
69 *
70 *  rtems_event_receive
71 *
72 *  This directive allows a thread to receive a set of events.
73 *
74 *  Input parameters:
75 *    event_in   - input event condition
76 *    option_set - options
77 *    ticks      - number of ticks to wait (0 means wait forever)
78 *    event_out  - pointer to output event set
79 *
80 *  Output parameters:
81 *    event out         - event set
82 *    RTEMS_SUCCESSFUL - if successful
83 *    error code        - if unsuccessful
84 */
85
86rtems_status_code rtems_event_receive(
87  rtems_event_set  event_in,
88  rtems_option     option_set,
89  rtems_interval   ticks,
90  rtems_event_set *event_out
91)
92{
93  if ( _Event_sets_Is_empty( event_in ) ) {
94    *event_out = _Thread_Executing->pending_events;
95    return( RTEMS_SUCCESSFUL );
96  }
97
98  _Thread_Disable_dispatch();
99  _Event_Seize( event_in, option_set, ticks );
100  _Thread_Enable_dispatch();
101  *event_out = _Thread_Executing->events_out;
102  return( _Thread_Executing->Wait.return_code );
103}
104
105/*PAGE
106 *
107 *  _Event_Seize
108 *
109 *  This routine attempts to satisfy the requested event condition
110 *  for the running thread.
111 *
112 *  Input parameters:
113 *    event_in   - the event condition to satisfy
114 *    option_set - acquire event options
115 *    ticks      - interval to wait
116 *
117 *  Output parameters: NONE
118 *
119 *  INTERRUPT LATENCY:
120 *    available
121 *    wait
122 *    check sync
123 */
124
125void _Event_Seize(
126  rtems_event_set event_in,
127  rtems_option    option_set,
128  rtems_interval  ticks
129)
130{
131  Thread_Control   *executing;
132  rtems_event_set   seized_events;
133  rtems_event_set   pending_events;
134  ISR_Level         level;
135
136  executing = _Thread_Executing;
137  executing->Wait.return_code = RTEMS_SUCCESSFUL;
138
139  _ISR_Disable( level );
140  pending_events = executing->pending_events;
141  seized_events  = _Event_sets_Get( pending_events, event_in );
142
143  if ( !_Event_sets_Is_empty( seized_events ) &&
144       (seized_events == event_in || _Options_Is_any( option_set )) ) {
145    executing->pending_events =
146      _Event_sets_Clear( pending_events, seized_events );
147    _ISR_Enable( level );
148    executing->events_out = seized_events;
149    return;
150  }
151
152  if ( _Options_Is_no_wait( option_set ) ) {
153    _ISR_Enable( level );
154    executing->Wait.return_code = RTEMS_UNSATISFIED;
155    executing->events_out = seized_events;
156    return;
157  }
158
159  _Event_Sync = TRUE;
160  executing->Wait.option_set            = option_set;
161  executing->Wait.Extra.event_condition = event_in;
162
163  _ISR_Enable( level );
164  _Thread_Set_state( executing, STATES_WAITING_FOR_EVENT );
165
166  if ( ticks ) {
167    _Watchdog_Initialize(
168      &executing->Timer,
169      _Event_Timeout,
170      executing->Object.id,
171      NULL
172    );
173    _Watchdog_Insert_ticks(
174      &executing->Timer,
175      ticks,
176      WATCHDOG_NO_ACTIVATE
177    );
178  }
179
180  _ISR_Disable( level );
181  if ( _Event_Sync == TRUE ) {
182    _Event_Sync = FALSE;
183    if ( ticks )
184      _Watchdog_Activate( &executing->Timer );
185    _ISR_Enable( level );
186    return;
187  }
188  _ISR_Enable( level );
189  (void) _Watchdog_Remove( &executing->Timer );
190  _Thread_Unblock( executing );
191  return;
192}
193
194/*PAGE
195 *
196 *  _Event_Surrender
197 *
198 *  This routines remove a thread from the specified threadq.
199 *
200 *  Input parameters:
201 *    the_thread - pointer to thread to be dequeued
202 *
203 *  Output parameters: NONE
204 *
205 *  INTERRUPT LATENCY:
206 *    before flash
207 *    after flash
208 *    check sync
209 */
210
211void _Event_Surrender(
212  Thread_Control *the_thread
213)
214{
215  ISR_Level          level;
216  rtems_event_set pending_events;
217  rtems_event_set event_condition;
218  rtems_event_set seized_events;
219
220  _ISR_Disable( level );
221  pending_events  = the_thread->pending_events;
222  event_condition = the_thread->Wait.Extra.event_condition;
223
224  seized_events = _Event_sets_Get( pending_events, event_condition );
225
226  if ( !_Event_sets_Is_empty( seized_events ) ) {
227    if ( _States_Is_waiting_for_event( the_thread->current_state ) ) {
228      if ( seized_events == event_condition ||
229                    _Options_Is_any( the_thread->Wait.option_set ) ) {
230        the_thread->pending_events =
231           _Event_sets_Clear( pending_events, seized_events );
232        (rtems_event_set *)the_thread->events_out = seized_events;
233
234        _ISR_Flash( level );
235
236        if ( !_Watchdog_Is_active( &the_thread->Timer ) ) {
237          _ISR_Enable( level );
238          _Thread_Unblock( the_thread );
239        }
240        else {
241          _Watchdog_Deactivate( &the_thread->Timer );
242          _ISR_Enable( level );
243          (void) _Watchdog_Remove( &the_thread->Timer );
244          _Thread_Unblock( the_thread );
245        }
246        return;
247      }
248    }
249    else if ( _Thread_Is_executing( the_thread ) && _Event_Sync == TRUE ) {
250      if ( seized_events == event_condition ||
251                    _Options_Is_any( the_thread->Wait.option_set ) ) {
252        the_thread->pending_events =
253           _Event_sets_Clear( pending_events,seized_events );
254        (rtems_event_set *)the_thread->events_out = seized_events;
255        _Event_Sync = FALSE;
256      }
257    }
258  }
259  _ISR_Enable( level );
260}
261
262/*PAGE
263 *
264 *  _Event_Timeout
265 *
266 *  This routine processes a thread which timeouts while waiting to
267 *  receive an event_set. It is called by the watchdog handler.
268 *
269 *  Input parameters:
270 *    id - thread id
271 *
272 *  Output parameters: NONE
273 */
274
275void _Event_Timeout(
276  Objects_Id  id,
277  void       *ignored
278)
279{
280  Thread_Control *the_thread;
281  Objects_Locations      location;
282
283  the_thread = _Thread_Get( id, &location );
284  switch ( location ) {
285    case OBJECTS_ERROR:
286    case OBJECTS_REMOTE:  /* impossible */
287      break;
288    case OBJECTS_LOCAL:
289      the_thread->Wait.return_code = RTEMS_TIMEOUT;
290      _Thread_Unblock( the_thread );
291      _Thread_Unnest_dispatch();
292      break;
293  }
294}
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