1 //----------------------------------------------------------------------
2 // Copyright (C) 2006 - 2007 by the FRESCOR consortium:
4 // Universidad de Cantabria, SPAIN
5 // University of York, UK
6 // Scuola Superiore Sant'Anna, ITALY
7 // Kaiserslautern University, GERMANY
8 // Univ. Politecnica Valencia, SPAIN
9 // Czech Technical University in Prague, CZECH REPUBLIC
11 // Thales Communication S.A. FRANCE
12 // Visual Tools S.A. SPAIN
13 // Rapita Systems Ltd UK
16 // See http://www.frescor.org
18 // The FRESCOR project (FP6/2005/IST/5-034026) is funded
19 // in part by the European Union Sixth Framework Programme
20 // The European Union is not liable of any use that may be
24 // based on previous work (FSF) done in the FIRST project
26 // Copyright (C) 2005 Mälardalen University, SWEDEN
27 // Scuola Superiore S.Anna, ITALY
28 // Universidad de Cantabria, SPAIN
29 // University of York, UK
31 // This file is part of FOSA (Frsh Operating System Abstraction)
33 // FOSA is free software; you can redistribute it and/or modify it
34 // under terms of the GNU General Public License as published by the
35 // Free Software Foundation; either version 2, or (at your option) any
36 // later version. FOSA is distributed in the hope that it will be
37 // useful, but WITHOUT ANY WARRANTY; without even the implied warranty
38 // of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
39 // General Public License for more details. You should have received a
40 // copy of the GNU General Public License along with FOSA; see file
41 // COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,
42 // Cambridge, MA 02139, USA.
44 // As a special exception, including FOSA header files in a file,
45 // instantiating FOSA generics or templates, or linking other files
46 // with FOSA objects to produce an executable application, does not
47 // by itself cause the resulting executable application to be covered
48 // by the GNU General Public License. This exception does not
49 // however invalidate any other reasons why the executable file might be
50 // covered by the GNU Public License.
51 // -----------------------------------------------------------------------
52 //fosa_clocks_and_timers.c
53 //==============================================
54 // ******** ****** ******** **********
55 // **///// /** ** **////// /** /**
56 // ** /** ** /** /** /**
57 // ******* /** ** /********* /**********
58 // **//// /** ** ////////** /**//////**
59 // ** /** ** /** /** /**
60 // ** /** ** ******** /** /**
61 // // /******/ //////// // //
63 // FOSA(Frescor Operating System Adaptation layer)
64 //================================================
71 #include "fosa_time.h"
72 #include "fosa_clocks_and_timers.h"
74 static const struct timespec zero_time={0,0};
77 /*************************
79 *************************/
84 * Get the time from a clock
86 * This function sets the variable pointed to by current_time to the
87 * current value of the clock specified by clockid, which may be the
88 * FOSA_CLOCK_REALTIME constant or a value obtained with
89 * fosa_get_cputime_clock()
91 * Returns 0 if successful; otherwise it returns an error code:
92 * EINVAL: the value of clockid is invalid
94 * Alternatively, in case of error the implementation is allowed to
95 * notify it to the system console and then terminate the FRSH
96 * implementation and dependant applications
98 int fosa_clock_get_time(fosa_clock_id_t clockid, fosa_abs_time_t *current_time)
100 struct timespec current_time_tspec;
103 ret_value = clock_gettime(clockid, ¤t_time_tspec);
104 *current_time = fosa_timespec_to_abs_time(current_time_tspec);
111 * fosa_get_cputime_clock()
113 * Get the identifier of a cpu-time clock
115 * This function stores in the variable pointed to by clockid the
116 * identifier of a cpu-time clock for the thread specified by tid.
118 * Returns 0 if successful; otherwise it returns an error code:
119 * EINVAL: the value of tid is invalid
121 * Alternatively, in case of error the implementation is allowed to
122 * notify it to the system console and then terminate the FRSH
123 * implementation and dependant applications
125 int fosa_thread_get_cputime_clock
126 (fosa_thread_id_t tid, fosa_clock_id_t *clockid)
128 return pthread_getcpuclockid(tid,clockid);
132 /*************************
134 *************************/
137 * fosa_create_timer()
139 * Create a one-shot timer
141 * This function creates a timer based on the clock specified by clock,
142 * and associates to this timer a notification mechanism consisting of
143 * a signal and associated information. Initially, the timer is in the
144 * disarmed state, i.e., not counting time. It can be armed to start
145 * counting time with fosa_timer_arm().
147 * The function stores the identifier of the newly created timer in the
148 * variable pointed to by timerid.
150 * When the timer expires, the signal number specified by signal will be
151 * sent together with the information specified by info, to the thread
152 * that armed the timer (@see fosa_timer_arm()).
154 * In those implementations that do not support queueing a
155 * signal with information to a thread (such as POSIX), the signal may
156 * be sent to any thread that is waiting for this signal via
157 * fosa_signal_wait(). Portability can be ensured by having the receiver
158 * thread be the one who is waiting for the signal.
160 * Returns 0 if successful; otherwise it returns an error code:
161 * EINVAL: the value of clockid or signal is invalid
163 * EAGAIN: the system lacks enough resources to create the timer
165 * Alternatively, in case of error the implementation is allowed to
166 * notify it to the system console and then terminate the FRSH
167 * implementation and dependant applications
169 int fosa_timer_create
170 (fosa_clock_id_t clockid, fosa_signal_t signal, fosa_signal_info_t info,
171 fosa_timer_id_t *timerid)
174 evp.sigev_notify=SIGEV_SIGNAL;
175 evp.sigev_signo=signal;
176 evp.sigev_value=* ((union sigval *) &info);
177 // the above casting construct is used to overcome the compiler
178 // restriction that does not allow casts between unions
179 return timer_create(clockid,&evp,timerid);
183 * fosa_timer_create_with_receiver()
185 * Create a one-shot timer with a specific signal receiver thread
187 * This function creates a timer in the same way as fosa_timer_create,
188 * except that the signal generated when the timer expires is sent to
189 * the thread specified by receiver
191 * Returns 0 if successful; otherwise it returns an error code:
192 * FOSA_EINVAL: the value of clockid or signal is invalid
194 * FOSA_EAGAIN: the system lacks enough resources to create the timer
196 * Alternatively, in case of error the implementation is allowed to
197 * notify it to the system console and then terminate the FRSH
198 * implementation and dependant applications
200 int fosa_timer_create_with_receiver
201 (fosa_clock_id_t clockid, fosa_signal_t signal, fosa_signal_info_t info,
202 fosa_timer_id_t *timerid, fosa_thread_id_t receiver)
204 // in POSIX the receiver thread cannot be specified
205 return fosa_timer_create(clockid,signal,info,timerid);
212 * The function deletes the timer specified by timerid, which becomes
213 * unusable. If the timer was armed, it is automatically disarmed before
216 * Returns 0 if successful; otherwise it returns an error code:
217 * EINVAL: the value of timerid is not valid
219 * Alternatively, in case of error the implementation is allowed to
220 * notify it to the system console and then terminate the FRSH
221 * implementation and dependant applications
223 int fosa_timer_delete(fosa_timer_id_t timerid)
225 return timer_delete(timerid);
230 * fosa_rel_timer_arm()
232 * Arm a timer with a relative time interval
234 * The timer specified by timer is armed and starts counting time.
236 * The value pointed to by value is the relative interval that must
237 * elapse for the timer to expire. Negative values cause the timer to
238 * expire immediately.
240 * The time is measured with the clock associated with the timer when
243 * If the timer was already armed, the previous time or interval is discarded
244 * and the timer is rearmed with the new value.
246 * When the timer expires, it is disarmed.
248 * Returns 0 if successful; otherwise it returns an error code:
249 * FOSA_EINVAL: the value of timerid or value is invalid
251 * Alternatively, in case of error the implementation is allowed to
252 * notify it to the system console and then terminate the FRSH
253 * implementation and dependant applications
255 int fosa_rel_timer_arm
256 (fosa_timer_id_t timerid, const fosa_rel_time_t *value)
258 struct itimerspec timer_value;
260 // set the timer to the specified value, one shot only
261 timer_value.it_value= fosa_rel_time_to_timespec(*value);
262 timer_value.it_interval=zero_time;
265 return timer_settime(timerid, 0, &timer_value,NULL);
270 * fosa_abs_timer_arm()
272 * Arm a timer that will expire in an absolute time instant.
274 * The timer specified by timer is armed and starts counting time.
276 * The value pointed to by value is the absolute time at which the
277 * timer will expire. If value specifies a time instant in the past,
278 * the timer expires immediately.
280 * The time is measured with the clock associated with the timer when
283 * If the timer was already armed, the previous time or interval is discarded
284 * and the timer is rearmed with the new value.
286 * When the timer expires, it is disarmed.
288 * Returns 0 if successful; otherwise it returns an error code:
289 * FOSA_EINVAL: the value of timerid or value is invalid
291 * Alternatively, in case of error the implementation is allowed to
292 * notify it to the system console and then terminate the FRSH
293 * implementation and dependant applications
295 int fosa_abs_timer_arm
296 (fosa_timer_id_t timerid, const fosa_abs_time_t *value)
298 struct itimerspec timer_value;
300 // set the timer to the specified value, one shot only
301 timer_value.it_value= fosa_abs_time_to_timespec(*value);
302 timer_value.it_interval=zero_time;
305 return timer_settime(timerid, TIMER_ABSTIME,&timer_value,NULL);
312 * fosa_timer_get_remaining_time()
314 * Get the remaining time for timer expiration
316 * Returns the relative remaining time for timer expiration. If the
317 * clock is a CPU clock it returns the time as if the thread was
318 * executing constantly.
320 * If the timer is disarmed it returns 0.
322 * Returns 0 if successful; otherwise it returns an error code:
323 * EINVAL: the value of timerid or value is invalid
325 * Alternatively, in case of error the implementation is allowed to
326 * notify it to the system console and then terminate the FRSH
327 * implementation and dependant applications
329 int fosa_timer_get_remaining_time
330 (fosa_timer_id_t timerid, fosa_rel_time_t *remaining_time)
332 struct itimerspec timer_value;
335 if (remaining_time == NULL) {
338 error_code=timer_gettime(timerid,&timer_value);
339 if (error_code==-1) return errno;
341 *remaining_time = fosa_timespec_to_rel_time(timer_value.it_value);
347 * fosa_timer_disarm()
351 * The timer specified by timer is disarmed, and will not expire unless
352 * it is rearmed. If the timer was already disramed, the function has
355 * If the pointer remaining_time is != NULL, the remaining time before
356 * expiration will be returned in that pointer. If the timer was
357 * disarmed a 0 value will be set.
359 * Returns 0 if successful; otherwise it returns an error code:
360 * EINVAL: the value of timerid or value is invalid
362 * Alternatively, in case of error the implementation is allowed to
363 * notify it to the system console and then terminate the FRSH
364 * implementation and dependant applications
366 int fosa_timer_disarm
367 (fosa_timer_id_t timerid,
368 fosa_rel_time_t *remaining_time)
370 struct itimerspec timer_value;
373 if (remaining_time!=NULL) {
374 error_code=timer_gettime(timerid,&timer_value);
375 if (error_code==-1) return errno;
376 *remaining_time = fosa_timespec_to_rel_time(timer_value.it_value);
378 timer_value.it_value=zero_time;
379 timer_value.it_interval=zero_time;
380 return timer_settime(timerid,0,&timer_value,NULL);