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;
62 /* There can only be one session at a time. */
63 /* 'session' is not static, it's used elsewhere (via 'extern'). */
64 struct sr_session *session;
67 * Create a new session.
69 * @todo Should it use the file-global "session" variable or take an argument?
70 * The same question applies to all the other session functions.
73 * @retval other A pointer to the newly allocated session.
77 SR_API struct sr_session *sr_session_new(void)
79 if (!(session = g_try_malloc0(sizeof(struct sr_session)))) {
80 sr_err("Session malloc failed.");
84 session->source_timeout = -1;
85 session->running = FALSE;
86 session->abort_session = FALSE;
87 g_mutex_init(&session->stop_mutex);
93 * Destroy the current session.
94 * This frees up all memory used by the session.
96 * @retval SR_OK Success.
97 * @retval SR_ERR_BUG No session exists.
101 SR_API int sr_session_destroy(void)
104 sr_err("%s: session was NULL", __func__);
108 sr_session_dev_remove_all();
109 g_mutex_clear(&session->stop_mutex);
110 if (session->trigger)
111 sr_trigger_free(session->trigger);
120 * Remove all the devices from the current session.
122 * The session itself (i.e., the struct sr_session) is not free'd and still
123 * exists after this function returns.
125 * @retval SR_OK Success.
126 * @retval SR_ERR_BUG No session exists.
130 SR_API int sr_session_dev_remove_all(void)
133 sr_err("%s: session was NULL", __func__);
137 g_slist_free(session->devs);
138 session->devs = NULL;
144 * Add a device instance to the current session.
146 * @param sdi The device instance to add to the current session. Must not
147 * be NULL. Also, sdi->driver and sdi->driver->dev_open must
150 * @retval SR_OK Success.
151 * @retval SR_ERR_ARG Invalid argument.
152 * @retval SR_ERR_BUG No session exists.
156 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
161 sr_err("%s: sdi was NULL", __func__);
166 sr_err("%s: session was NULL", __func__);
170 /* If sdi->driver is NULL, this is a virtual device. */
172 sr_dbg("%s: sdi->driver was NULL, this seems to be "
173 "a virtual device; continuing", __func__);
174 /* Just add the device, don't run dev_open(). */
175 session->devs = g_slist_append(session->devs, (gpointer)sdi);
179 /* sdi->driver is non-NULL (i.e. we have a real device). */
180 if (!sdi->driver->dev_open) {
181 sr_err("%s: sdi->driver->dev_open was NULL", __func__);
185 session->devs = g_slist_append(session->devs, (gpointer)sdi);
187 if (session->running) {
188 /* Adding a device to a running session. Commit settings
189 * and start acquisition on that device now. */
190 if ((ret = sr_config_commit(sdi)) != SR_OK) {
191 sr_err("Failed to commit device settings before "
192 "starting acquisition in running session (%s)",
196 if ((ret = sdi->driver->dev_acquisition_start(sdi,
197 (void *)sdi)) != SR_OK) {
198 sr_err("Failed to start acquisition of device in "
199 "running session (%s)", sr_strerror(ret));
208 * List all device instances attached to the current session.
210 * @param devlist A pointer where the device instance list will be
211 * stored on return. If no devices are in the session,
212 * this will be NULL. Each element in the list points
213 * to a struct sr_dev_inst *.
214 * The list must be freed by the caller, but not the
215 * elements pointed to.
217 * @retval SR_OK Success.
218 * @retval SR_ERR Invalid argument.
222 SR_API int sr_session_dev_list(GSList **devlist)
230 *devlist = g_slist_copy(session->devs);
236 * Remove all datafeed callbacks in the current session.
238 * @retval SR_OK Success.
239 * @retval SR_ERR_BUG No session exists.
243 SR_API int sr_session_datafeed_callback_remove_all(void)
246 sr_err("%s: session was NULL", __func__);
250 g_slist_free_full(session->datafeed_callbacks, g_free);
251 session->datafeed_callbacks = NULL;
257 * Add a datafeed callback to the current session.
259 * @param cb Function to call when a chunk of data is received.
261 * @param cb_data Opaque pointer passed in by the caller.
263 * @retval SR_OK Success.
264 * @retval SR_ERR_BUG No session exists.
268 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback cb, void *cb_data)
270 struct datafeed_callback *cb_struct;
273 sr_err("%s: session was NULL", __func__);
278 sr_err("%s: cb was NULL", __func__);
282 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
283 return SR_ERR_MALLOC;
286 cb_struct->cb_data = cb_data;
288 session->datafeed_callbacks =
289 g_slist_append(session->datafeed_callbacks, cb_struct);
294 SR_API struct sr_trigger *sr_session_trigger_get(void)
296 return session->trigger;
299 SR_API int sr_session_trigger_set(struct sr_trigger *trig)
301 session->trigger = trig;
307 * Call every device in the session's callback.
309 * For sessions not driven by select loops such as sr_session_run(),
310 * but driven by another scheduler, this can be used to poll the devices
311 * from within that scheduler.
313 * @param block If TRUE, this call will wait for any of the session's
314 * sources to fire an event on the file descriptors, or
315 * any of their timeouts to activate. In other words, this
316 * can be used as a select loop.
317 * If FALSE, all sources have their callback run, regardless
318 * of file descriptor or timeout status.
320 * @retval SR_OK Success.
321 * @retval SR_ERR Error occured.
323 static int sr_session_iteration(gboolean block)
328 ret = g_poll(session->pollfds, session->num_sources,
329 block ? session->source_timeout : 0);
330 for (i = 0; i < session->num_sources; i++) {
331 if (session->pollfds[i].revents > 0 || (ret == 0
332 && session->source_timeout == session->sources[i].timeout)) {
334 * Invoke the source's callback on an event,
335 * or if the poll timed out and this source
336 * asked for that timeout.
338 if (!session->sources[i].cb(session->pollfds[i].fd,
339 session->pollfds[i].revents,
340 session->sources[i].cb_data))
341 sr_session_source_remove(session->sources[i].poll_object);
344 * We want to take as little time as possible to stop
345 * the session if we have been told to do so. Therefore,
346 * we check the flag after processing every source, not
347 * just once per main event loop.
349 g_mutex_lock(&session->stop_mutex);
350 if (session->abort_session) {
351 sr_session_stop_sync();
352 /* But once is enough. */
353 session->abort_session = FALSE;
355 g_mutex_unlock(&session->stop_mutex);
362 static int verify_trigger(struct sr_trigger *trigger)
364 struct sr_trigger_stage *stage;
365 struct sr_trigger_match *match;
368 if (!trigger->stages) {
369 sr_err("No trigger stages defined.");
373 sr_spew("Checking trigger:");
374 for (l = trigger->stages; l; l = l->next) {
376 if (!stage->matches) {
377 sr_err("Stage %d has no matches defined.", stage->stage);
380 for (m = stage->matches; m; m = m->next) {
382 if (!match->channel) {
383 sr_err("Stage %d match has no channel.", stage->stage);
387 sr_err("Stage %d match is not defined.", stage->stage);
390 sr_spew("Stage %d match on channel %s, match %d", stage->stage,
391 match->channel->name, match->match);
400 * There can only be one session at a time.
402 * @retval SR_OK Success.
403 * @retval SR_ERR Error occured.
407 SR_API int sr_session_start(void)
409 struct sr_dev_inst *sdi;
414 sr_err("%s: session was NULL; a session must be "
415 "created before starting it.", __func__);
419 if (!session->devs) {
420 sr_err("%s: session->devs was NULL; a session "
421 "cannot be started without devices.", __func__);
425 if (session->trigger && verify_trigger(session->trigger) != SR_OK)
428 sr_info("Starting.");
431 for (l = session->devs; l; l = l->next) {
433 if ((ret = sr_config_commit(sdi)) != SR_OK) {
434 sr_err("Failed to commit device settings before "
435 "starting acquisition (%s)", sr_strerror(ret));
438 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
439 sr_err("%s: could not start an acquisition "
440 "(%s)", __func__, sr_strerror(ret));
445 /* TODO: What if there are multiple devices? Which return code? */
453 * @retval SR_OK Success.
454 * @retval SR_ERR_BUG Error occured.
458 SR_API int sr_session_run(void)
461 sr_err("%s: session was NULL; a session must be "
462 "created first, before running it.", __func__);
466 if (!session->devs) {
467 /* TODO: Actually the case? */
468 sr_err("%s: session->devs was NULL; a session "
469 "cannot be run without devices.", __func__);
472 session->running = TRUE;
476 /* Do we have real sources? */
477 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
478 /* Dummy source, freewheel over it. */
479 while (session->num_sources)
480 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
482 /* Real sources, use g_poll() main loop. */
483 while (session->num_sources)
484 sr_session_iteration(TRUE);
491 * Stop the current session.
493 * The current session is stopped immediately, with all acquisition sessions
494 * being stopped and hardware drivers cleaned up.
496 * This must be called from within the session thread, to prevent freeing
497 * resources that the session thread will try to use.
499 * @retval SR_OK Success.
500 * @retval SR_ERR_BUG No session exists.
504 SR_PRIV int sr_session_stop_sync(void)
506 struct sr_dev_inst *sdi;
510 sr_err("%s: session was NULL", __func__);
514 sr_info("Stopping.");
516 for (l = session->devs; l; l = l->next) {
519 if (sdi->driver->dev_acquisition_stop)
520 sdi->driver->dev_acquisition_stop(sdi, sdi);
523 session->running = FALSE;
529 * Stop the current session.
531 * The current session is stopped immediately, with all acquisition sessions
532 * being stopped and hardware drivers cleaned up.
534 * If the session is run in a separate thread, this function will not block
535 * until the session is finished executing. It is the caller's responsibility
536 * to wait for the session thread to return before assuming that the session is
537 * completely decommissioned.
539 * @retval SR_OK Success.
540 * @retval SR_ERR_BUG No session exists.
544 SR_API int sr_session_stop(void)
547 sr_err("%s: session was NULL", __func__);
551 g_mutex_lock(&session->stop_mutex);
552 session->abort_session = TRUE;
553 g_mutex_unlock(&session->stop_mutex);
561 * @param packet The packet to show debugging information for.
563 static void datafeed_dump(const struct sr_datafeed_packet *packet)
565 const struct sr_datafeed_logic *logic;
566 const struct sr_datafeed_analog *analog;
568 switch (packet->type) {
570 sr_dbg("bus: Received SR_DF_HEADER packet.");
573 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
576 sr_dbg("bus: Received SR_DF_META packet.");
579 logic = packet->payload;
580 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes, "
581 "unitsize = %d).", logic->length, logic->unitsize);
584 analog = packet->payload;
585 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
586 analog->num_samples);
589 sr_dbg("bus: Received SR_DF_END packet.");
591 case SR_DF_FRAME_BEGIN:
592 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
594 case SR_DF_FRAME_END:
595 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
598 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
604 * Send a packet to whatever is listening on the datafeed bus.
606 * Hardware drivers use this to send a data packet to the frontend.
609 * @param packet The datafeed packet to send to the session bus.
611 * @retval SR_OK Success.
612 * @retval SR_ERR_ARG Invalid argument.
616 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
617 const struct sr_datafeed_packet *packet)
620 struct datafeed_callback *cb_struct;
623 sr_err("%s: sdi was NULL", __func__);
628 sr_err("%s: packet was NULL", __func__);
632 for (l = session->datafeed_callbacks; l; l = l->next) {
633 if (sr_log_loglevel_get() >= SR_LOG_DBG)
634 datafeed_dump(packet);
636 cb_struct->cb(sdi, packet, cb_struct->cb_data);
643 * Add an event source for a file descriptor.
645 * @param pollfd The GPollFD.
646 * @param[in] timeout Max time to wait before the callback is called,
648 * @param cb Callback function to add. Must not be NULL.
649 * @param cb_data Data for the callback function. Can be NULL.
650 * @param poll_object TODO.
652 * @retval SR_OK Success.
653 * @retval SR_ERR_ARG Invalid argument.
654 * @retval SR_ERR_MALLOC Memory allocation error.
656 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
657 sr_receive_data_callback cb, void *cb_data, gintptr poll_object)
659 struct source *new_sources, *s;
660 GPollFD *new_pollfds;
663 sr_err("%s: cb was NULL", __func__);
667 /* Note: cb_data can be NULL, that's not a bug. */
669 new_pollfds = g_try_realloc(session->pollfds,
670 sizeof(GPollFD) * (session->num_sources + 1));
672 sr_err("%s: new_pollfds malloc failed", __func__);
673 return SR_ERR_MALLOC;
676 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
677 (session->num_sources + 1));
679 sr_err("%s: new_sources malloc failed", __func__);
680 return SR_ERR_MALLOC;
683 new_pollfds[session->num_sources] = *pollfd;
684 s = &new_sources[session->num_sources++];
685 s->timeout = timeout;
687 s->cb_data = cb_data;
688 s->poll_object = poll_object;
689 session->pollfds = new_pollfds;
690 session->sources = new_sources;
692 if (timeout != session->source_timeout && timeout > 0
693 && (session->source_timeout == -1 || timeout < session->source_timeout))
694 session->source_timeout = timeout;
700 * Add an event source for a file descriptor.
702 * @param fd The file descriptor.
703 * @param events Events to check for.
704 * @param timeout Max time to wait before the callback is called, ignored if 0.
705 * @param cb Callback function to add. Must not be NULL.
706 * @param cb_data Data for the callback function. Can be NULL.
708 * @retval SR_OK Success.
709 * @retval SR_ERR_ARG Invalid argument.
710 * @retval SR_ERR_MALLOC Memory allocation error.
714 SR_API int sr_session_source_add(int fd, int events, int timeout,
715 sr_receive_data_callback cb, void *cb_data)
722 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
726 * Add an event source for a GPollFD.
728 * @param pollfd The GPollFD.
729 * @param timeout Max time to wait before the callback is called, ignored if 0.
730 * @param cb Callback function to add. Must not be NULL.
731 * @param cb_data Data for the callback function. Can be NULL.
733 * @retval SR_OK Success.
734 * @retval SR_ERR_ARG Invalid argument.
735 * @retval SR_ERR_MALLOC Memory allocation error.
739 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
740 sr_receive_data_callback cb, void *cb_data)
742 return _sr_session_source_add(pollfd, timeout, cb,
743 cb_data, (gintptr)pollfd);
747 * Add an event source for a GIOChannel.
749 * @param channel The GIOChannel.
750 * @param events Events to poll on.
751 * @param timeout Max time to wait before the callback is called, ignored if 0.
752 * @param cb Callback function to add. Must not be NULL.
753 * @param cb_data Data for the callback function. Can be NULL.
755 * @retval SR_OK Success.
756 * @retval SR_ERR_ARG Invalid argument.
757 * @retval SR_ERR_MALLOC Memory allocation error.
761 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
762 int timeout, sr_receive_data_callback cb, void *cb_data)
767 g_io_channel_win32_make_pollfd(channel, events, &p);
769 p.fd = g_io_channel_unix_get_fd(channel);
773 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
777 * Remove the source belonging to the specified channel.
779 * @todo Add more error checks and logging.
781 * @param poll_object The channel for which the source should be removed.
783 * @retval SR_OK Success
784 * @retval SR_ERR_ARG Invalid arguments
785 * @retval SR_ERR_MALLOC Memory allocation error
786 * @retval SR_ERR_BUG Internal error
788 static int _sr_session_source_remove(gintptr poll_object)
790 struct source *new_sources;
791 GPollFD *new_pollfds;
794 if (!session->sources || !session->num_sources) {
795 sr_err("%s: sources was NULL", __func__);
799 for (old = 0; old < session->num_sources; old++) {
800 if (session->sources[old].poll_object == poll_object)
804 /* fd not found, nothing to do */
805 if (old == session->num_sources)
808 session->num_sources -= 1;
810 if (old != session->num_sources) {
811 memmove(&session->pollfds[old], &session->pollfds[old+1],
812 (session->num_sources - old) * sizeof(GPollFD));
813 memmove(&session->sources[old], &session->sources[old+1],
814 (session->num_sources - old) * sizeof(struct source));
817 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
818 if (!new_pollfds && session->num_sources > 0) {
819 sr_err("%s: new_pollfds malloc failed", __func__);
820 return SR_ERR_MALLOC;
823 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
824 if (!new_sources && session->num_sources > 0) {
825 sr_err("%s: new_sources malloc failed", __func__);
826 return SR_ERR_MALLOC;
829 session->pollfds = new_pollfds;
830 session->sources = new_sources;
836 * Remove the source belonging to the specified file descriptor.
838 * @param fd The file descriptor for which the source should be removed.
840 * @retval SR_OK Success
841 * @retval SR_ERR_ARG Invalid argument
842 * @retval SR_ERR_MALLOC Memory allocation error.
843 * @retval SR_ERR_BUG Internal error.
847 SR_API int sr_session_source_remove(int fd)
849 return _sr_session_source_remove((gintptr)fd);
853 * Remove the source belonging to the specified poll descriptor.
855 * @param pollfd The poll descriptor for which the source should be removed.
857 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
858 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
863 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
865 return _sr_session_source_remove((gintptr)pollfd);
869 * Remove the source belonging to the specified channel.
871 * @param channel The channel for which the source should be removed.
873 * @retval SR_OK Success.
874 * @retval SR_ERR_ARG Invalid argument.
875 * @retval SR_ERR_MALLOC Memory allocation error.
876 * @return SR_ERR_BUG Internal error.
880 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
882 return _sr_session_source_remove((gintptr)channel);