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"
28 /* Message logging helpers with subsystem-specific prefix string. */
29 #define LOG_PREFIX "session: "
30 #define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
31 #define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
32 #define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
33 #define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
34 #define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
35 #define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
40 * Creating, using, or destroying libsigrok sessions.
44 * @defgroup grp_session Session handling
46 * Creating, using, or destroying libsigrok sessions.
53 sr_receive_data_callback_t cb;
56 /* This is used to keep track of the object (fd, pollfd or channel) which is
57 * being polled and will be used to match the source when removing it again.
62 struct datafeed_callback {
63 sr_datafeed_callback_t cb;
67 /* There can only be one session at a time. */
68 /* 'session' is not static, it's used elsewhere (via 'extern'). */
69 struct sr_session *session;
72 * Create a new session.
74 * @todo Should it use the file-global "session" variable or take an argument?
75 * The same question applies to all the other session functions.
78 * @retval other A pointer to the newly allocated session->
80 SR_API struct sr_session *sr_session_new(void)
82 if (!(session = g_try_malloc0(sizeof(struct sr_session)))) {
83 sr_err("Session malloc failed.");
87 session->source_timeout = -1;
88 session->running = FALSE;
89 session->abort_session = FALSE;
90 g_mutex_init(&session->stop_mutex);
96 * Destroy the current session.
97 * This frees up all memory used by the session.
99 * @retval SR_OK Success.
100 * @retval SR_ERR_BUG No session exists.
102 SR_API int sr_session_destroy(void)
105 sr_err("%s: session was NULL", __func__);
109 sr_session_dev_remove_all();
111 /* TODO: Error checks needed? */
113 g_mutex_clear(&session->stop_mutex);
122 * Remove all the devices from the current session.
124 * The session itself (i.e., the struct sr_session) is not free'd and still
125 * exists after this function returns.
127 * @retval SR_OK Success.
128 * @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.
154 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
159 sr_err("%s: sdi was NULL", __func__);
164 sr_err("%s: session was NULL", __func__);
168 /* If sdi->driver is NULL, this is a virtual device. */
170 sr_dbg("%s: sdi->driver was NULL, this seems to be "
171 "a virtual device; continuing", __func__);
172 /* Just add the device, don't run dev_open(). */
173 session->devs = g_slist_append(session->devs, (gpointer)sdi);
177 /* sdi->driver is non-NULL (i.e. we have a real device). */
178 if (!sdi->driver->dev_open) {
179 sr_err("%s: sdi->driver->dev_open was NULL", __func__);
183 session->devs = g_slist_append(session->devs, (gpointer)sdi);
185 if (session->running) {
186 /* Adding a device to a running session. Start acquisition
187 * on that device now. */
188 if ((ret = sdi->driver->dev_acquisition_start(sdi,
189 (void *)sdi)) != SR_OK)
190 sr_err("Failed to start acquisition of device in "
191 "running session: %d", ret);
198 * List all device instances attached to the current session.
200 * @param devlist A pointer where the device instance list will be
201 * stored on return. If no devices are in the session,
202 * this will be NULL. Each element in the list points
203 * to a struct sr_dev_inst *.
204 * The list must be freed by the caller, but not the
205 * elements pointed to.
207 * @retval SR_OK Success.
208 * @retval SR_ERR Invalid argument.
210 SR_API int sr_session_dev_list(GSList **devlist)
218 *devlist = g_slist_copy(session->devs);
224 * Remove all datafeed callbacks in the current session.
226 * @retval SR_OK Success.
227 * @retval SR_ERR_BUG No session exists.
229 SR_API int sr_session_datafeed_callback_remove_all(void)
232 sr_err("%s: session was NULL", __func__);
236 g_slist_free_full(session->datafeed_callbacks, g_free);
237 session->datafeed_callbacks = NULL;
243 * Add a datafeed callback to the current session.
245 * @param cb Function to call when a chunk of data is received.
247 * @param cb_data Opaque pointer passed in by the caller.
249 * @retval SR_OK Success.
250 * @retval SR_ERR_BUG No session exists.
252 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb, void *cb_data)
254 struct datafeed_callback *cb_struct;
257 sr_err("%s: session was NULL", __func__);
262 sr_err("%s: cb was NULL", __func__);
266 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
267 return SR_ERR_MALLOC;
270 cb_struct->cb_data = cb_data;
272 session->datafeed_callbacks =
273 g_slist_append(session->datafeed_callbacks, cb_struct);
279 * Call every device in the session's callback.
281 * For sessions not driven by select loops such as sr_session_run(),
282 * but driven by another scheduler, this can be used to poll the devices
283 * from within that scheduler.
285 * @param block If TRUE, this call will wait for any of the session's
286 * sources to fire an event on the file descriptors, or
287 * any of their timeouts to activate. In other words, this
288 * can be used as a select loop.
289 * If FALSE, all sources have their callback run, regardless
290 * of file descriptor or timeout status.
292 * @retval SR_OK Success.
293 * @retval SR_ERR Error occured.
295 static int sr_session_iteration(gboolean block)
300 ret = g_poll(session->pollfds, session->num_sources,
301 block ? session->source_timeout : 0);
302 for (i = 0; i < session->num_sources; i++) {
303 if (session->pollfds[i].revents > 0 || (ret == 0
304 && session->source_timeout == session->sources[i].timeout)) {
306 * Invoke the source's callback on an event,
307 * or if the poll timed out and this source
308 * asked for that timeout.
310 if (!session->sources[i].cb(session->pollfds[i].fd,
311 session->pollfds[i].revents,
312 session->sources[i].cb_data))
313 sr_session_source_remove(session->sources[i].poll_object);
316 * We want to take as little time as possible to stop
317 * the session if we have been told to do so. Therefore,
318 * we check the flag after processing every source, not
319 * just once per main event loop.
321 g_mutex_lock(&session->stop_mutex);
322 if (session->abort_session) {
323 sr_session_stop_sync();
324 /* But once is enough. */
325 session->abort_session = FALSE;
327 g_mutex_unlock(&session->stop_mutex);
336 * There can only be one session at a time.
338 * @retval SR_OK Success.
339 * @retval SR_ERR Error occured.
341 SR_API int sr_session_start(void)
343 struct sr_dev_inst *sdi;
348 sr_err("%s: session was NULL; a session must be "
349 "created before starting it.", __func__);
353 if (!session->devs) {
354 sr_err("%s: session->devs was NULL; a session "
355 "cannot be started without devices.", __func__);
359 sr_info("Starting.");
362 for (l = session->devs; l; l = l->next) {
364 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
365 sr_err("%s: could not start an acquisition "
366 "(%s)", __func__, sr_strerror(ret));
371 /* TODO: What if there are multiple devices? Which return code? */
379 * @retval SR_OK Success.
380 * @retval SR_ERR_BUG Error occured.
382 SR_API int sr_session_run(void)
385 sr_err("%s: session was NULL; a session must be "
386 "created first, before running it.", __func__);
390 if (!session->devs) {
391 /* TODO: Actually the case? */
392 sr_err("%s: session->devs was NULL; a session "
393 "cannot be run without devices.", __func__);
396 session->running = TRUE;
400 /* Do we have real sources? */
401 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
402 /* Dummy source, freewheel over it. */
403 while (session->num_sources)
404 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
406 /* Real sources, use g_poll() main loop. */
407 while (session->num_sources)
408 sr_session_iteration(TRUE);
415 * Stop the current session.
417 * The current session is stopped immediately, with all acquisition sessions
418 * being stopped and hardware drivers cleaned up.
420 * This must be called from within the session thread, to prevent freeing
421 * resources that the session thread will try to use.
423 * @retval SR_OK Success.
424 * @retval SR_ERR_BUG No session exists.
428 SR_PRIV int sr_session_stop_sync(void)
430 struct sr_dev_inst *sdi;
434 sr_err("%s: session was NULL", __func__);
438 sr_info("Stopping.");
440 for (l = session->devs; l; l = l->next) {
443 if (sdi->driver->dev_acquisition_stop)
444 sdi->driver->dev_acquisition_stop(sdi, sdi);
447 session->running = FALSE;
453 * Stop the current session.
455 * The current session is stopped immediately, with all acquisition sessions
456 * being stopped and hardware drivers cleaned up.
458 * If the session is run in a separate thread, this function will not block
459 * until the session is finished executing. It is the caller's responsibility
460 * to wait for the session thread to return before assuming that the session is
461 * completely decommissioned.
463 * @retval SR_OK Success.
464 * @retval SR_ERR_BUG No session exists.
466 SR_API int sr_session_stop(void)
469 sr_err("%s: session was NULL", __func__);
473 g_mutex_lock(&session->stop_mutex);
474 session->abort_session = TRUE;
475 g_mutex_unlock(&session->stop_mutex);
483 * @param packet The packet to show debugging information for.
485 static void datafeed_dump(const struct sr_datafeed_packet *packet)
487 const struct sr_datafeed_logic *logic;
488 const struct sr_datafeed_analog *analog;
490 switch (packet->type) {
492 sr_dbg("bus: Received SR_DF_HEADER packet.");
495 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
498 sr_dbg("bus: Received SR_DF_META packet.");
501 logic = packet->payload;
502 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
506 analog = packet->payload;
507 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
508 analog->num_samples);
511 sr_dbg("bus: Received SR_DF_END packet.");
513 case SR_DF_FRAME_BEGIN:
514 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
516 case SR_DF_FRAME_END:
517 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
520 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
526 * Send a packet to whatever is listening on the datafeed bus.
528 * Hardware drivers use this to send a data packet to the frontend.
531 * @param packet The datafeed packet to send to the session bus.
533 * @retval SR_OK Success.
534 * @retval SR_ERR_ARG Invalid argument.
538 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
539 const struct sr_datafeed_packet *packet)
542 struct datafeed_callback *cb_struct;
545 sr_err("%s: sdi was NULL", __func__);
550 sr_err("%s: packet was NULL", __func__);
554 for (l = session->datafeed_callbacks; l; l = l->next) {
555 if (sr_log_loglevel_get() >= SR_LOG_DBG)
556 datafeed_dump(packet);
558 cb_struct->cb(sdi, packet, cb_struct->cb_data);
565 * Add an event source for a file descriptor.
567 * @param pollfd The GPollFD.
568 * @param[in] timeout Max time to wait before the callback is called,
570 * @param cb Callback function to add. Must not be NULL.
571 * @param cb_data Data for the callback function. Can be NULL.
572 * @param poll_object TODO.
574 * @retval SR_OK Success.
575 * @retval SR_ERR_ARG Invalid argument.
576 * @retval SR_ERR_MALLOC Memory allocation error.
578 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
579 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
581 struct source *new_sources, *s;
582 GPollFD *new_pollfds;
585 sr_err("%s: cb was NULL", __func__);
589 /* Note: cb_data can be NULL, that's not a bug. */
591 new_pollfds = g_try_realloc(session->pollfds,
592 sizeof(GPollFD) * (session->num_sources + 1));
594 sr_err("%s: new_pollfds malloc failed", __func__);
595 return SR_ERR_MALLOC;
598 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
599 (session->num_sources + 1));
601 sr_err("%s: new_sources malloc failed", __func__);
602 return SR_ERR_MALLOC;
605 new_pollfds[session->num_sources] = *pollfd;
606 s = &new_sources[session->num_sources++];
607 s->timeout = timeout;
609 s->cb_data = cb_data;
610 s->poll_object = poll_object;
611 session->pollfds = new_pollfds;
612 session->sources = new_sources;
614 if (timeout != session->source_timeout && timeout > 0
615 && (session->source_timeout == -1 || timeout < session->source_timeout))
616 session->source_timeout = timeout;
622 * Add an event source for a file descriptor.
624 * @param fd The file descriptor.
625 * @param events Events to check for.
626 * @param timeout Max time to wait before the callback is called, ignored if 0.
627 * @param cb Callback function to add. Must not be NULL.
628 * @param cb_data Data for the callback function. Can be NULL.
630 * @retval SR_OK Success.
631 * @retval SR_ERR_ARG Invalid argument.
632 * @retval SR_ERR_MALLOC Memory allocation error.
634 SR_API int sr_session_source_add(int fd, int events, int timeout,
635 sr_receive_data_callback_t cb, void *cb_data)
642 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
646 * Add an event source for a GPollFD.
648 * @param pollfd The GPollFD.
649 * @param timeout Max time to wait before the callback is called, ignored if 0.
650 * @param cb Callback function to add. Must not be NULL.
651 * @param cb_data Data for the callback function. Can be NULL.
653 * @retval SR_OK Success.
654 * @retval SR_ERR_ARG Invalid argument.
655 * @retval SR_ERR_MALLOC Memory allocation error.
657 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
658 sr_receive_data_callback_t cb, void *cb_data)
660 return _sr_session_source_add(pollfd, timeout, cb,
661 cb_data, (gintptr)pollfd);
665 * Add an event source for a GIOChannel.
667 * @param channel The GIOChannel.
668 * @param events Events to poll on.
669 * @param timeout Max time to wait before the callback is called, ignored if 0.
670 * @param cb Callback function to add. Must not be NULL.
671 * @param cb_data Data for the callback function. Can be NULL.
673 * @retval SR_OK Success.
674 * @retval SR_ERR_ARG Invalid argument.
675 * @retval SR_ERR_MALLOC Memory allocation error.
677 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
678 int timeout, sr_receive_data_callback_t cb, void *cb_data)
683 g_io_channel_win32_make_pollfd(channel, events, &p);
685 p.fd = g_io_channel_unix_get_fd(channel);
689 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
693 * Remove the source belonging to the specified channel.
695 * @todo Add more error checks and logging.
697 * @param poll_object The channel for which the source should be removed.
699 * @retval SR_OK Success
700 * @retval SR_ERR_ARG Invalid arguments
701 * @retval SR_ERR_MALLOC Memory allocation error
702 * @retval SR_ERR_BUG Internal error
704 static int _sr_session_source_remove(gintptr poll_object)
706 struct source *new_sources;
707 GPollFD *new_pollfds;
710 if (!session->sources || !session->num_sources) {
711 sr_err("%s: sources was NULL", __func__);
715 for (old = 0; old < session->num_sources; old++) {
716 if (session->sources[old].poll_object == poll_object)
720 /* fd not found, nothing to do */
721 if (old == session->num_sources)
724 session->num_sources -= 1;
726 if (old != session->num_sources) {
727 memmove(&session->pollfds[old], &session->pollfds[old+1],
728 (session->num_sources - old) * sizeof(GPollFD));
729 memmove(&session->sources[old], &session->sources[old+1],
730 (session->num_sources - old) * sizeof(struct source));
733 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
734 if (!new_pollfds && session->num_sources > 0) {
735 sr_err("%s: new_pollfds malloc failed", __func__);
736 return SR_ERR_MALLOC;
739 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
740 if (!new_sources && session->num_sources > 0) {
741 sr_err("%s: new_sources malloc failed", __func__);
742 return SR_ERR_MALLOC;
745 session->pollfds = new_pollfds;
746 session->sources = new_sources;
752 * Remove the source belonging to the specified file descriptor.
754 * @param fd The file descriptor for which the source should be removed.
756 * @retval SR_OK Success
757 * @retval SR_ERR_ARG Invalid argument
758 * @retval SR_ERR_MALLOC Memory allocation error.
759 * @retval SR_ERR_BUG Internal error.
761 SR_API int sr_session_source_remove(int fd)
763 return _sr_session_source_remove((gintptr)fd);
767 * Remove the source belonging to the specified poll descriptor.
769 * @param pollfd The poll descriptor for which the source should be removed.
771 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
772 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
775 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
777 return _sr_session_source_remove((gintptr)pollfd);
781 * Remove the source belonging to the specified channel.
783 * @param channel The channel for which the source should be removed.
785 * @retval SR_OK Success.
786 * @retval SR_ERR_ARG Invalid argument.
787 * @retval SR_ERR_MALLOC Memory allocation error.
788 * @return SR_ERR_BUG Internal error.
790 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
792 return _sr_session_source_remove((gintptr)channel);