2 * This file is part of the libsigrok project.
4 * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 #include "libsigrok.h"
26 #include "libsigrok-internal.h"
29 #define LOG_PREFIX "session"
35 * Creating, using, or destroying libsigrok sessions.
39 * @defgroup grp_session Session handling
41 * Creating, using, or destroying libsigrok sessions.
48 sr_receive_data_callback cb;
51 /* This is used to keep track of the object (fd, pollfd or channel) which is
52 * being polled and will be used to match the source when removing it again.
57 struct datafeed_callback {
58 sr_datafeed_callback cb;
63 * Create a new session.
65 * @param new_session This will contain a pointer to the newly created
66 * session if the return value is SR_OK, otherwise the value
67 * is undefined and should not be used. Must not be NULL.
69 * @retval SR_OK Success.
70 * @retval SR_ERR_ARG Invalid argument.
74 SR_API int sr_session_new(struct sr_session **new_session)
76 struct sr_session *session;
81 session = g_malloc0(sizeof(struct sr_session));
83 session->source_timeout = -1;
84 session->running = FALSE;
85 session->abort_session = FALSE;
86 g_mutex_init(&session->stop_mutex);
88 *new_session = session;
95 * This frees up all memory used by the session.
97 * @param session The session to destroy. Must not be NULL.
99 * @retval SR_OK Success.
100 * @retval SR_ERR_ARG Invalid session passed.
104 SR_API int sr_session_destroy(struct sr_session *session)
107 sr_err("%s: session was NULL", __func__);
111 sr_session_dev_remove_all(session);
112 g_mutex_clear(&session->stop_mutex);
113 if (session->trigger)
114 sr_trigger_free(session->trigger);
122 * Remove all the devices from a session.
124 * The session itself (i.e., the struct sr_session) is not free'd and still
125 * exists after this function returns.
127 * @param session The session to use. Must not be NULL.
129 * @retval SR_OK Success.
130 * @retval SR_ERR_BUG Invalid session passed.
134 SR_API int sr_session_dev_remove_all(struct sr_session *session)
136 struct sr_dev_inst *sdi;
140 sr_err("%s: session was NULL", __func__);
144 for (l = session->devs; l; l = l->next) {
145 sdi = (struct sr_dev_inst *) l->data;
149 g_slist_free(session->devs);
150 session->devs = NULL;
156 * Add a device instance to a session.
158 * @param session The session to add to. Must not be NULL.
159 * @param sdi The device instance to add to a session. Must not
160 * be NULL. Also, sdi->driver and sdi->driver->dev_open must
163 * @retval SR_OK Success.
164 * @retval SR_ERR_ARG Invalid argument.
168 SR_API int sr_session_dev_add(struct sr_session *session,
169 struct sr_dev_inst *sdi)
174 sr_err("%s: sdi was NULL", __func__);
179 sr_err("%s: session was NULL", __func__);
183 /* If sdi->session is not NULL, the device is already in this or
184 * another session. */
186 sr_err("%s: already assigned to session", __func__);
190 /* If sdi->driver is NULL, this is a virtual device. */
192 sr_dbg("%s: sdi->driver was NULL, this seems to be "
193 "a virtual device; continuing", __func__);
194 /* Just add the device, don't run dev_open(). */
195 session->devs = g_slist_append(session->devs, (gpointer)sdi);
196 sdi->session = session;
200 /* sdi->driver is non-NULL (i.e. we have a real device). */
201 if (!sdi->driver->dev_open) {
202 sr_err("%s: sdi->driver->dev_open was NULL", __func__);
206 session->devs = g_slist_append(session->devs, (gpointer)sdi);
207 sdi->session = session;
209 if (session->running) {
210 /* Adding a device to a running session. Commit settings
211 * and start acquisition on that device now. */
212 if ((ret = sr_config_commit(sdi)) != SR_OK) {
213 sr_err("Failed to commit device settings before "
214 "starting acquisition in running session (%s)",
218 if ((ret = sdi->driver->dev_acquisition_start(sdi,
219 (void *)sdi)) != SR_OK) {
220 sr_err("Failed to start acquisition of device in "
221 "running session (%s)", sr_strerror(ret));
230 * List all device instances attached to a session.
232 * @param session The session to use. Must not be NULL.
233 * @param devlist A pointer where the device instance list will be
234 * stored on return. If no devices are in the session,
235 * this will be NULL. Each element in the list points
236 * to a struct sr_dev_inst *.
237 * The list must be freed by the caller, but not the
238 * elements pointed to.
240 * @retval SR_OK Success.
241 * @retval SR_ERR_ARG Invalid argument.
245 SR_API int sr_session_dev_list(struct sr_session *session, GSList **devlist)
253 *devlist = g_slist_copy(session->devs);
259 * Remove all datafeed callbacks in a session.
261 * @param session The session to use. Must not be NULL.
263 * @retval SR_OK Success.
264 * @retval SR_ERR_ARG Invalid session passed.
268 SR_API int sr_session_datafeed_callback_remove_all(struct sr_session *session)
271 sr_err("%s: session was NULL", __func__);
275 g_slist_free_full(session->datafeed_callbacks, g_free);
276 session->datafeed_callbacks = NULL;
282 * Add a datafeed callback to a session.
284 * @param session The session to use. Must not be NULL.
285 * @param cb Function to call when a chunk of data is received.
287 * @param cb_data Opaque pointer passed in by the caller.
289 * @retval SR_OK Success.
290 * @retval SR_ERR_BUG No session exists.
294 SR_API int sr_session_datafeed_callback_add(struct sr_session *session,
295 sr_datafeed_callback cb, void *cb_data)
297 struct datafeed_callback *cb_struct;
300 sr_err("%s: session was NULL", __func__);
305 sr_err("%s: cb was NULL", __func__);
309 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
310 return SR_ERR_MALLOC;
313 cb_struct->cb_data = cb_data;
315 session->datafeed_callbacks =
316 g_slist_append(session->datafeed_callbacks, cb_struct);
321 SR_API struct sr_trigger *sr_session_trigger_get(struct sr_session *session)
323 return session->trigger;
326 SR_API int sr_session_trigger_set(struct sr_session *session, struct sr_trigger *trig)
328 session->trigger = trig;
334 * Call every device in the current session's callback.
336 * For sessions not driven by select loops such as sr_session_run(),
337 * but driven by another scheduler, this can be used to poll the devices
338 * from within that scheduler.
340 * @param session The session to use. Must not be NULL.
341 * @param block If TRUE, this call will wait for any of the session's
342 * sources to fire an event on the file descriptors, or
343 * any of their timeouts to activate. In other words, this
344 * can be used as a select loop.
345 * If FALSE, all sources have their callback run, regardless
346 * of file descriptor or timeout status.
348 * @retval SR_OK Success.
349 * @retval SR_ERR Error occured.
351 static int sr_session_iteration(struct sr_session *session, gboolean block)
356 ret = g_poll(session->pollfds, session->num_sources,
357 block ? session->source_timeout : 0);
358 for (i = 0; i < session->num_sources; i++) {
359 if (session->pollfds[i].revents > 0 || (ret == 0
360 && session->source_timeout == session->sources[i].timeout)) {
362 * Invoke the source's callback on an event,
363 * or if the poll timed out and this source
364 * asked for that timeout.
366 if (!session->sources[i].cb(session->pollfds[i].fd,
367 session->pollfds[i].revents,
368 session->sources[i].cb_data))
369 sr_session_source_remove(session,
370 session->sources[i].poll_object);
373 * We want to take as little time as possible to stop
374 * the session if we have been told to do so. Therefore,
375 * we check the flag after processing every source, not
376 * just once per main event loop.
378 g_mutex_lock(&session->stop_mutex);
379 if (session->abort_session) {
380 sr_session_stop_sync(session);
381 /* But once is enough. */
382 session->abort_session = FALSE;
384 g_mutex_unlock(&session->stop_mutex);
391 static int verify_trigger(struct sr_trigger *trigger)
393 struct sr_trigger_stage *stage;
394 struct sr_trigger_match *match;
397 if (!trigger->stages) {
398 sr_err("No trigger stages defined.");
402 sr_spew("Checking trigger:");
403 for (l = trigger->stages; l; l = l->next) {
405 if (!stage->matches) {
406 sr_err("Stage %d has no matches defined.", stage->stage);
409 for (m = stage->matches; m; m = m->next) {
411 if (!match->channel) {
412 sr_err("Stage %d match has no channel.", stage->stage);
416 sr_err("Stage %d match is not defined.", stage->stage);
419 sr_spew("Stage %d match on channel %s, match %d", stage->stage,
420 match->channel->name, match->match);
429 * @param session The session to use. Must not be NULL.
431 * @retval SR_OK Success.
432 * @retval SR_ERR_ARG Invalid session passed.
436 SR_API int sr_session_start(struct sr_session *session)
438 struct sr_dev_inst *sdi;
443 sr_err("%s: session was NULL", __func__);
447 if (!session->devs) {
448 sr_err("%s: session->devs was NULL; a session "
449 "cannot be started without devices.", __func__);
453 if (session->trigger && verify_trigger(session->trigger) != SR_OK)
456 sr_info("Starting.");
459 for (l = session->devs; l; l = l->next) {
461 if ((ret = sr_config_commit(sdi)) != SR_OK) {
462 sr_err("Failed to commit device settings before "
463 "starting acquisition (%s)", sr_strerror(ret));
466 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
467 sr_err("%s: could not start an acquisition "
468 "(%s)", __func__, sr_strerror(ret));
473 /* TODO: What if there are multiple devices? Which return code? */
481 * @param session The session to use. Must not be NULL.
483 * @retval SR_OK Success.
484 * @retval SR_ERR_ARG Invalid session passed.
488 SR_API int sr_session_run(struct sr_session *session)
491 sr_err("%s: session was NULL", __func__);
495 if (!session->devs) {
496 /* TODO: Actually the case? */
497 sr_err("%s: session->devs was NULL; a session "
498 "cannot be run without devices.", __func__);
501 session->running = TRUE;
505 /* Do we have real sources? */
506 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
507 /* Dummy source, freewheel over it. */
508 while (session->num_sources)
509 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
511 /* Real sources, use g_poll() main loop. */
512 while (session->num_sources)
513 sr_session_iteration(session, TRUE);
522 * The session is stopped immediately, with all acquisition sessions stopped
523 * and hardware drivers cleaned up.
525 * This must be called from within the session thread, to prevent freeing
526 * resources that the session thread will try to use.
528 * @param session The session to use. Must not be NULL.
530 * @retval SR_OK Success.
531 * @retval SR_ERR_ARG Invalid session passed.
535 SR_PRIV int sr_session_stop_sync(struct sr_session *session)
537 struct sr_dev_inst *sdi;
541 sr_err("%s: session was NULL", __func__);
545 sr_info("Stopping.");
547 for (l = session->devs; l; l = l->next) {
550 if (sdi->driver->dev_acquisition_stop)
551 sdi->driver->dev_acquisition_stop(sdi, sdi);
554 session->running = FALSE;
562 * The session is stopped immediately, with all acquisition sessions being
563 * stopped and hardware drivers cleaned up.
565 * If the session is run in a separate thread, this function will not block
566 * until the session is finished executing. It is the caller's responsibility
567 * to wait for the session thread to return before assuming that the session is
568 * completely decommissioned.
570 * @param session The session to use. Must not be NULL.
572 * @retval SR_OK Success.
573 * @retval SR_ERR_ARG Invalid session passed.
577 SR_API int sr_session_stop(struct sr_session *session)
580 sr_err("%s: session was NULL", __func__);
584 g_mutex_lock(&session->stop_mutex);
585 session->abort_session = TRUE;
586 g_mutex_unlock(&session->stop_mutex);
594 * @param packet The packet to show debugging information for.
596 static void datafeed_dump(const struct sr_datafeed_packet *packet)
598 const struct sr_datafeed_logic *logic;
599 const struct sr_datafeed_analog *analog;
601 switch (packet->type) {
603 sr_dbg("bus: Received SR_DF_HEADER packet.");
606 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
609 sr_dbg("bus: Received SR_DF_META packet.");
612 logic = packet->payload;
613 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes, "
614 "unitsize = %d).", logic->length, logic->unitsize);
617 analog = packet->payload;
618 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
619 analog->num_samples);
622 sr_dbg("bus: Received SR_DF_END packet.");
624 case SR_DF_FRAME_BEGIN:
625 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
627 case SR_DF_FRAME_END:
628 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
631 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
637 * Send a packet to whatever is listening on the datafeed bus.
639 * Hardware drivers use this to send a data packet to the frontend.
642 * @param packet The datafeed packet to send to the session bus.
644 * @retval SR_OK Success.
645 * @retval SR_ERR_ARG Invalid argument.
649 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
650 const struct sr_datafeed_packet *packet)
653 struct datafeed_callback *cb_struct;
656 sr_err("%s: sdi was NULL", __func__);
661 sr_err("%s: packet was NULL", __func__);
665 for (l = sdi->session->datafeed_callbacks; l; l = l->next) {
666 if (sr_log_loglevel_get() >= SR_LOG_DBG)
667 datafeed_dump(packet);
669 cb_struct->cb(sdi, packet, cb_struct->cb_data);
676 * Add an event source for a file descriptor.
678 * @param session The session to use. Must not be NULL.
679 * @param pollfd The GPollFD.
680 * @param[in] timeout Max time to wait before the callback is called,
682 * @param cb Callback function to add. Must not be NULL.
683 * @param cb_data Data for the callback function. Can be NULL.
684 * @param poll_object TODO.
686 * @retval SR_OK Success.
687 * @retval SR_ERR_ARG Invalid argument.
688 * @retval SR_ERR_MALLOC Memory allocation error.
690 static int _sr_session_source_add(struct sr_session *session, GPollFD *pollfd,
691 int timeout, sr_receive_data_callback cb, void *cb_data, gintptr poll_object)
693 struct source *new_sources, *s;
694 GPollFD *new_pollfds;
697 sr_err("%s: cb was NULL", __func__);
701 /* Note: cb_data can be NULL, that's not a bug. */
703 new_pollfds = g_try_realloc(session->pollfds,
704 sizeof(GPollFD) * (session->num_sources + 1));
706 sr_err("%s: new_pollfds malloc failed", __func__);
707 return SR_ERR_MALLOC;
710 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
711 (session->num_sources + 1));
713 sr_err("%s: new_sources malloc failed", __func__);
714 return SR_ERR_MALLOC;
717 new_pollfds[session->num_sources] = *pollfd;
718 s = &new_sources[session->num_sources++];
719 s->timeout = timeout;
721 s->cb_data = cb_data;
722 s->poll_object = poll_object;
723 session->pollfds = new_pollfds;
724 session->sources = new_sources;
726 if (timeout != session->source_timeout && timeout > 0
727 && (session->source_timeout == -1 || timeout < session->source_timeout))
728 session->source_timeout = timeout;
734 * Add an event source for a file descriptor.
736 * @param session The session to use. Must not be NULL.
737 * @param fd The file descriptor.
738 * @param events Events to check for.
739 * @param timeout Max time to wait before the callback is called, ignored if 0.
740 * @param cb Callback function to add. Must not be NULL.
741 * @param cb_data Data for the callback function. Can be NULL.
743 * @retval SR_OK Success.
744 * @retval SR_ERR_ARG Invalid argument.
745 * @retval SR_ERR_MALLOC Memory allocation error.
749 SR_API int sr_session_source_add(struct sr_session *session, int fd,
750 int events, int timeout, sr_receive_data_callback cb, void *cb_data)
757 return _sr_session_source_add(session, &p, timeout, cb, cb_data, (gintptr)fd);
761 * Add an event source for a GPollFD.
763 * @param session The session to use. Must not be NULL.
764 * @param pollfd The GPollFD.
765 * @param timeout Max time to wait before the callback is called, ignored if 0.
766 * @param cb Callback function to add. Must not be NULL.
767 * @param cb_data Data for the callback function. Can be NULL.
769 * @retval SR_OK Success.
770 * @retval SR_ERR_ARG Invalid argument.
771 * @retval SR_ERR_MALLOC Memory allocation error.
775 SR_API int sr_session_source_add_pollfd(struct sr_session *session,
776 GPollFD *pollfd, int timeout, sr_receive_data_callback cb,
779 return _sr_session_source_add(session, pollfd, timeout, cb,
780 cb_data, (gintptr)pollfd);
784 * Add an event source for a GIOChannel.
786 * @param session The session to use. Must not be NULL.
787 * @param channel The GIOChannel.
788 * @param events Events to poll on.
789 * @param timeout Max time to wait before the callback is called, ignored if 0.
790 * @param cb Callback function to add. Must not be NULL.
791 * @param cb_data Data for the callback function. Can be NULL.
793 * @retval SR_OK Success.
794 * @retval SR_ERR_ARG Invalid argument.
795 * @retval SR_ERR_MALLOC Memory allocation error.
799 SR_API int sr_session_source_add_channel(struct sr_session *session,
800 GIOChannel *channel, int events, int timeout,
801 sr_receive_data_callback cb, void *cb_data)
806 g_io_channel_win32_make_pollfd(channel, events, &p);
808 p.fd = g_io_channel_unix_get_fd(channel);
812 return _sr_session_source_add(session, &p, timeout, cb, cb_data, (gintptr)channel);
816 * Remove the source belonging to the specified channel.
818 * @todo Add more error checks and logging.
820 * @param session The session to use. Must not be NULL.
821 * @param poll_object The channel for which the source should be removed.
823 * @retval SR_OK Success
824 * @retval SR_ERR_ARG Invalid arguments
825 * @retval SR_ERR_MALLOC Memory allocation error
826 * @retval SR_ERR_BUG Internal error
828 static int _sr_session_source_remove(struct sr_session *session, gintptr poll_object)
830 struct source *new_sources;
831 GPollFD *new_pollfds;
834 if (!session->sources || !session->num_sources) {
835 sr_err("%s: sources was NULL", __func__);
839 for (old = 0; old < session->num_sources; old++) {
840 if (session->sources[old].poll_object == poll_object)
844 /* fd not found, nothing to do */
845 if (old == session->num_sources)
848 session->num_sources -= 1;
850 if (old != session->num_sources) {
851 memmove(&session->pollfds[old], &session->pollfds[old+1],
852 (session->num_sources - old) * sizeof(GPollFD));
853 memmove(&session->sources[old], &session->sources[old+1],
854 (session->num_sources - old) * sizeof(struct source));
857 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
858 if (!new_pollfds && session->num_sources > 0) {
859 sr_err("%s: new_pollfds malloc failed", __func__);
860 return SR_ERR_MALLOC;
863 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
864 if (!new_sources && session->num_sources > 0) {
865 sr_err("%s: new_sources malloc failed", __func__);
866 return SR_ERR_MALLOC;
869 session->pollfds = new_pollfds;
870 session->sources = new_sources;
876 * Remove the source belonging to the specified file descriptor.
878 * @param session The session to use. Must not be NULL.
879 * @param fd The file descriptor for which the source should be removed.
881 * @retval SR_OK Success
882 * @retval SR_ERR_ARG Invalid argument
883 * @retval SR_ERR_MALLOC Memory allocation error.
884 * @retval SR_ERR_BUG Internal error.
888 SR_API int sr_session_source_remove(struct sr_session *session, int fd)
890 return _sr_session_source_remove(session, (gintptr)fd);
894 * Remove the source belonging to the specified poll descriptor.
896 * @param session The session to use. Must not be NULL.
897 * @param pollfd The poll descriptor for which the source should be removed.
899 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
900 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
905 SR_API int sr_session_source_remove_pollfd(struct sr_session *session,
908 return _sr_session_source_remove(session, (gintptr)pollfd);
912 * Remove the source belonging to the specified channel.
914 * @param session The session to use. Must not be NULL.
915 * @param channel The channel for which the source should be removed.
917 * @retval SR_OK Success.
918 * @retval SR_ERR_ARG Invalid argument.
919 * @retval SR_ERR_MALLOC Memory allocation error.
920 * @return SR_ERR_BUG Internal error.
924 SR_API int sr_session_source_remove_channel(struct sr_session *session,
927 return _sr_session_source_remove(session, (gintptr)channel);