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();
110 /* TODO: Error checks needed? */
112 g_mutex_clear(&session->stop_mutex);
121 * Remove all the devices from the current session.
123 * The session itself (i.e., the struct sr_session) is not free'd and still
124 * exists after this function returns.
126 * @retval SR_OK Success.
127 * @retval SR_ERR_BUG No session exists.
131 SR_API int sr_session_dev_remove_all(void)
134 sr_err("%s: session was NULL", __func__);
138 g_slist_free(session->devs);
139 session->devs = NULL;
145 * Add a device instance to the current session.
147 * @param sdi The device instance to add to the current session. Must not
148 * be NULL. Also, sdi->driver and sdi->driver->dev_open must
151 * @retval SR_OK Success.
152 * @retval SR_ERR_ARG Invalid argument.
153 * @retval SR_ERR_BUG No session exists.
157 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
162 sr_err("%s: sdi was NULL", __func__);
167 sr_err("%s: session was NULL", __func__);
171 /* If sdi->driver is NULL, this is a virtual device. */
173 sr_dbg("%s: sdi->driver was NULL, this seems to be "
174 "a virtual device; continuing", __func__);
175 /* Just add the device, don't run dev_open(). */
176 session->devs = g_slist_append(session->devs, (gpointer)sdi);
180 /* sdi->driver is non-NULL (i.e. we have a real device). */
181 if (!sdi->driver->dev_open) {
182 sr_err("%s: sdi->driver->dev_open was NULL", __func__);
186 session->devs = g_slist_append(session->devs, (gpointer)sdi);
188 if (session->running) {
189 /* Adding a device to a running session. Commit settings
190 * and start acquisition on that device now. */
191 if ((ret = sr_config_commit(sdi)) != SR_OK) {
192 sr_err("Failed to commit device settings before "
193 "starting acquisition in running session (%s)",
197 if ((ret = sdi->driver->dev_acquisition_start(sdi,
198 (void *)sdi)) != SR_OK) {
199 sr_err("Failed to start acquisition of device in "
200 "running session (%s)", sr_strerror(ret));
209 * List all device instances attached to the current session.
211 * @param devlist A pointer where the device instance list will be
212 * stored on return. If no devices are in the session,
213 * this will be NULL. Each element in the list points
214 * to a struct sr_dev_inst *.
215 * The list must be freed by the caller, but not the
216 * elements pointed to.
218 * @retval SR_OK Success.
219 * @retval SR_ERR Invalid argument.
223 SR_API int sr_session_dev_list(GSList **devlist)
231 *devlist = g_slist_copy(session->devs);
237 * Remove all datafeed callbacks in the current session.
239 * @retval SR_OK Success.
240 * @retval SR_ERR_BUG No session exists.
244 SR_API int sr_session_datafeed_callback_remove_all(void)
247 sr_err("%s: session was NULL", __func__);
251 g_slist_free_full(session->datafeed_callbacks, g_free);
252 session->datafeed_callbacks = NULL;
258 * Add a datafeed callback to the current session.
260 * @param cb Function to call when a chunk of data is received.
262 * @param cb_data Opaque pointer passed in by the caller.
264 * @retval SR_OK Success.
265 * @retval SR_ERR_BUG No session exists.
269 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback cb, void *cb_data)
271 struct datafeed_callback *cb_struct;
274 sr_err("%s: session was NULL", __func__);
279 sr_err("%s: cb was NULL", __func__);
283 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
284 return SR_ERR_MALLOC;
287 cb_struct->cb_data = cb_data;
289 session->datafeed_callbacks =
290 g_slist_append(session->datafeed_callbacks, cb_struct);
295 SR_PRIV struct sr_trigger *sr_session_trigger_get(void)
297 return session->trigger;
300 SR_API int sr_session_trigger_set(struct sr_trigger *trig)
302 session->trigger = trig;
308 * Call every device in the session's callback.
310 * For sessions not driven by select loops such as sr_session_run(),
311 * but driven by another scheduler, this can be used to poll the devices
312 * from within that scheduler.
314 * @param block If TRUE, this call will wait for any of the session's
315 * sources to fire an event on the file descriptors, or
316 * any of their timeouts to activate. In other words, this
317 * can be used as a select loop.
318 * If FALSE, all sources have their callback run, regardless
319 * of file descriptor or timeout status.
321 * @retval SR_OK Success.
322 * @retval SR_ERR Error occured.
324 static int sr_session_iteration(gboolean block)
329 ret = g_poll(session->pollfds, session->num_sources,
330 block ? session->source_timeout : 0);
331 for (i = 0; i < session->num_sources; i++) {
332 if (session->pollfds[i].revents > 0 || (ret == 0
333 && session->source_timeout == session->sources[i].timeout)) {
335 * Invoke the source's callback on an event,
336 * or if the poll timed out and this source
337 * asked for that timeout.
339 if (!session->sources[i].cb(session->pollfds[i].fd,
340 session->pollfds[i].revents,
341 session->sources[i].cb_data))
342 sr_session_source_remove(session->sources[i].poll_object);
345 * We want to take as little time as possible to stop
346 * the session if we have been told to do so. Therefore,
347 * we check the flag after processing every source, not
348 * just once per main event loop.
350 g_mutex_lock(&session->stop_mutex);
351 if (session->abort_session) {
352 sr_session_stop_sync();
353 /* But once is enough. */
354 session->abort_session = FALSE;
356 g_mutex_unlock(&session->stop_mutex);
363 static int verify_trigger(struct sr_trigger *trigger)
365 struct sr_trigger_stage *stage;
366 struct sr_trigger_match *match;
369 if (!trigger->stages) {
370 sr_err("No trigger stages defined.");
374 sr_spew("Checking trigger:");
375 for (l = trigger->stages; l; l = l->next) {
377 if (!stage->matches) {
378 sr_err("Stage %d has no matches defined.", stage->stage);
381 for (m = stage->matches; m; m = m->next) {
383 if (!match->channel) {
384 sr_err("Stage %d match has no channel.", stage->stage);
388 sr_err("Stage %d match is not defined.", stage->stage);
391 sr_spew("Stage %d match on channel %s, match %d", stage->stage,
392 match->channel->name, match->match);
401 * There can only be one session at a time.
403 * @retval SR_OK Success.
404 * @retval SR_ERR Error occured.
408 SR_API int sr_session_start(void)
410 struct sr_dev_inst *sdi;
415 sr_err("%s: session was NULL; a session must be "
416 "created before starting it.", __func__);
420 if (!session->devs) {
421 sr_err("%s: session->devs was NULL; a session "
422 "cannot be started without devices.", __func__);
426 if (session->trigger && verify_trigger(session->trigger) != SR_OK)
429 sr_info("Starting.");
432 for (l = session->devs; l; l = l->next) {
434 if ((ret = sr_config_commit(sdi)) != SR_OK) {
435 sr_err("Failed to commit device settings before "
436 "starting acquisition (%s)", sr_strerror(ret));
439 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
440 sr_err("%s: could not start an acquisition "
441 "(%s)", __func__, sr_strerror(ret));
446 /* TODO: What if there are multiple devices? Which return code? */
454 * @retval SR_OK Success.
455 * @retval SR_ERR_BUG Error occured.
459 SR_API int sr_session_run(void)
462 sr_err("%s: session was NULL; a session must be "
463 "created first, before running it.", __func__);
467 if (!session->devs) {
468 /* TODO: Actually the case? */
469 sr_err("%s: session->devs was NULL; a session "
470 "cannot be run without devices.", __func__);
473 session->running = TRUE;
477 /* Do we have real sources? */
478 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
479 /* Dummy source, freewheel over it. */
480 while (session->num_sources)
481 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
483 /* Real sources, use g_poll() main loop. */
484 while (session->num_sources)
485 sr_session_iteration(TRUE);
492 * Stop the current session.
494 * The current session is stopped immediately, with all acquisition sessions
495 * being stopped and hardware drivers cleaned up.
497 * This must be called from within the session thread, to prevent freeing
498 * resources that the session thread will try to use.
500 * @retval SR_OK Success.
501 * @retval SR_ERR_BUG No session exists.
505 SR_PRIV int sr_session_stop_sync(void)
507 struct sr_dev_inst *sdi;
511 sr_err("%s: session was NULL", __func__);
515 sr_info("Stopping.");
517 for (l = session->devs; l; l = l->next) {
520 if (sdi->driver->dev_acquisition_stop)
521 sdi->driver->dev_acquisition_stop(sdi, sdi);
524 session->running = FALSE;
530 * Stop the current session.
532 * The current session is stopped immediately, with all acquisition sessions
533 * being stopped and hardware drivers cleaned up.
535 * If the session is run in a separate thread, this function will not block
536 * until the session is finished executing. It is the caller's responsibility
537 * to wait for the session thread to return before assuming that the session is
538 * completely decommissioned.
540 * @retval SR_OK Success.
541 * @retval SR_ERR_BUG No session exists.
545 SR_API int sr_session_stop(void)
548 sr_err("%s: session was NULL", __func__);
552 g_mutex_lock(&session->stop_mutex);
553 session->abort_session = TRUE;
554 g_mutex_unlock(&session->stop_mutex);
562 * @param packet The packet to show debugging information for.
564 static void datafeed_dump(const struct sr_datafeed_packet *packet)
566 const struct sr_datafeed_logic *logic;
567 const struct sr_datafeed_analog *analog;
569 switch (packet->type) {
571 sr_dbg("bus: Received SR_DF_HEADER packet.");
574 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
577 sr_dbg("bus: Received SR_DF_META packet.");
580 logic = packet->payload;
581 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes, "
582 "unitsize = %d).", logic->length, logic->unitsize);
585 analog = packet->payload;
586 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
587 analog->num_samples);
590 sr_dbg("bus: Received SR_DF_END packet.");
592 case SR_DF_FRAME_BEGIN:
593 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
595 case SR_DF_FRAME_END:
596 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
599 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
605 * Send a packet to whatever is listening on the datafeed bus.
607 * Hardware drivers use this to send a data packet to the frontend.
610 * @param packet The datafeed packet to send to the session bus.
612 * @retval SR_OK Success.
613 * @retval SR_ERR_ARG Invalid argument.
617 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
618 const struct sr_datafeed_packet *packet)
621 struct datafeed_callback *cb_struct;
624 sr_err("%s: sdi was NULL", __func__);
629 sr_err("%s: packet was NULL", __func__);
633 for (l = session->datafeed_callbacks; l; l = l->next) {
634 if (sr_log_loglevel_get() >= SR_LOG_DBG)
635 datafeed_dump(packet);
637 cb_struct->cb(sdi, packet, cb_struct->cb_data);
644 * Add an event source for a file descriptor.
646 * @param pollfd The GPollFD.
647 * @param[in] timeout Max time to wait before the callback is called,
649 * @param cb Callback function to add. Must not be NULL.
650 * @param cb_data Data for the callback function. Can be NULL.
651 * @param poll_object TODO.
653 * @retval SR_OK Success.
654 * @retval SR_ERR_ARG Invalid argument.
655 * @retval SR_ERR_MALLOC Memory allocation error.
657 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
658 sr_receive_data_callback cb, void *cb_data, gintptr poll_object)
660 struct source *new_sources, *s;
661 GPollFD *new_pollfds;
664 sr_err("%s: cb was NULL", __func__);
668 /* Note: cb_data can be NULL, that's not a bug. */
670 new_pollfds = g_try_realloc(session->pollfds,
671 sizeof(GPollFD) * (session->num_sources + 1));
673 sr_err("%s: new_pollfds malloc failed", __func__);
674 return SR_ERR_MALLOC;
677 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
678 (session->num_sources + 1));
680 sr_err("%s: new_sources malloc failed", __func__);
681 return SR_ERR_MALLOC;
684 new_pollfds[session->num_sources] = *pollfd;
685 s = &new_sources[session->num_sources++];
686 s->timeout = timeout;
688 s->cb_data = cb_data;
689 s->poll_object = poll_object;
690 session->pollfds = new_pollfds;
691 session->sources = new_sources;
693 if (timeout != session->source_timeout && timeout > 0
694 && (session->source_timeout == -1 || timeout < session->source_timeout))
695 session->source_timeout = timeout;
701 * Add an event source for a file descriptor.
703 * @param fd The file descriptor.
704 * @param events Events to check for.
705 * @param timeout Max time to wait before the callback is called, ignored if 0.
706 * @param cb Callback function to add. Must not be NULL.
707 * @param cb_data Data for the callback function. Can be NULL.
709 * @retval SR_OK Success.
710 * @retval SR_ERR_ARG Invalid argument.
711 * @retval SR_ERR_MALLOC Memory allocation error.
715 SR_API int sr_session_source_add(int fd, int events, int timeout,
716 sr_receive_data_callback cb, void *cb_data)
723 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
727 * Add an event source for a GPollFD.
729 * @param pollfd The GPollFD.
730 * @param timeout Max time to wait before the callback is called, ignored if 0.
731 * @param cb Callback function to add. Must not be NULL.
732 * @param cb_data Data for the callback function. Can be NULL.
734 * @retval SR_OK Success.
735 * @retval SR_ERR_ARG Invalid argument.
736 * @retval SR_ERR_MALLOC Memory allocation error.
740 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
741 sr_receive_data_callback cb, void *cb_data)
743 return _sr_session_source_add(pollfd, timeout, cb,
744 cb_data, (gintptr)pollfd);
748 * Add an event source for a GIOChannel.
750 * @param channel The GIOChannel.
751 * @param events Events to poll on.
752 * @param timeout Max time to wait before the callback is called, ignored if 0.
753 * @param cb Callback function to add. Must not be NULL.
754 * @param cb_data Data for the callback function. Can be NULL.
756 * @retval SR_OK Success.
757 * @retval SR_ERR_ARG Invalid argument.
758 * @retval SR_ERR_MALLOC Memory allocation error.
762 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
763 int timeout, sr_receive_data_callback cb, void *cb_data)
768 g_io_channel_win32_make_pollfd(channel, events, &p);
770 p.fd = g_io_channel_unix_get_fd(channel);
774 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
778 * Remove the source belonging to the specified channel.
780 * @todo Add more error checks and logging.
782 * @param poll_object The channel for which the source should be removed.
784 * @retval SR_OK Success
785 * @retval SR_ERR_ARG Invalid arguments
786 * @retval SR_ERR_MALLOC Memory allocation error
787 * @retval SR_ERR_BUG Internal error
789 static int _sr_session_source_remove(gintptr poll_object)
791 struct source *new_sources;
792 GPollFD *new_pollfds;
795 if (!session->sources || !session->num_sources) {
796 sr_err("%s: sources was NULL", __func__);
800 for (old = 0; old < session->num_sources; old++) {
801 if (session->sources[old].poll_object == poll_object)
805 /* fd not found, nothing to do */
806 if (old == session->num_sources)
809 session->num_sources -= 1;
811 if (old != session->num_sources) {
812 memmove(&session->pollfds[old], &session->pollfds[old+1],
813 (session->num_sources - old) * sizeof(GPollFD));
814 memmove(&session->sources[old], &session->sources[old+1],
815 (session->num_sources - old) * sizeof(struct source));
818 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
819 if (!new_pollfds && session->num_sources > 0) {
820 sr_err("%s: new_pollfds malloc failed", __func__);
821 return SR_ERR_MALLOC;
824 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
825 if (!new_sources && session->num_sources > 0) {
826 sr_err("%s: new_sources malloc failed", __func__);
827 return SR_ERR_MALLOC;
830 session->pollfds = new_pollfds;
831 session->sources = new_sources;
837 * Remove the source belonging to the specified file descriptor.
839 * @param fd The file descriptor for which the source should be removed.
841 * @retval SR_OK Success
842 * @retval SR_ERR_ARG Invalid argument
843 * @retval SR_ERR_MALLOC Memory allocation error.
844 * @retval SR_ERR_BUG Internal error.
848 SR_API int sr_session_source_remove(int fd)
850 return _sr_session_source_remove((gintptr)fd);
854 * Remove the source belonging to the specified poll descriptor.
856 * @param pollfd The poll descriptor for which the source should be removed.
858 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
859 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
864 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
866 return _sr_session_source_remove((gintptr)pollfd);
870 * Remove the source belonging to the specified channel.
872 * @param channel The channel for which the source should be removed.
874 * @retval SR_OK Success.
875 * @retval SR_ERR_ARG Invalid argument.
876 * @retval SR_ERR_MALLOC Memory allocation error.
877 * @return SR_ERR_BUG Internal error.
881 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
883 return _sr_session_source_remove((gintptr)channel);