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.
77 * @return A pointer to the newly allocated session, or NULL upon errors.
79 SR_API struct sr_session *sr_session_new(void)
81 if (!(session = g_try_malloc0(sizeof(struct sr_session)))) {
82 sr_err("Session malloc failed.");
86 session->source_timeout = -1;
87 session->running = FALSE;
88 session->abort_session = FALSE;
89 g_mutex_init(&session->stop_mutex);
95 * Destroy the current session.
97 * This frees up all memory used by the session.
99 * @return SR_OK upon success, SR_ERR_BUG if 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 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
128 SR_API int sr_session_dev_remove_all(void)
131 sr_err("%s: session was NULL", __func__);
135 g_slist_free(session->devs);
136 session->devs = NULL;
142 * Add a device instance to the current session.
144 * @param sdi The device instance to add to the current session. Must not
145 * be NULL. Also, sdi->driver and sdi->driver->dev_open must
148 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
150 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
155 sr_err("%s: sdi was NULL", __func__);
160 sr_err("%s: session was NULL", __func__);
164 /* If sdi->driver is NULL, this is a virtual device. */
166 sr_dbg("%s: sdi->driver was NULL, this seems to be "
167 "a virtual device; continuing", __func__);
168 /* Just add the device, don't run dev_open(). */
169 session->devs = g_slist_append(session->devs, (gpointer)sdi);
173 /* sdi->driver is non-NULL (i.e. we have a real device). */
174 if (!sdi->driver->dev_open) {
175 sr_err("%s: sdi->driver->dev_open was NULL", __func__);
179 session->devs = g_slist_append(session->devs, (gpointer)sdi);
181 if (session->running) {
182 /* Adding a device to a running session. Start acquisition
183 * on that device now. */
184 if ((ret = sdi->driver->dev_acquisition_start(sdi,
185 (void *)sdi)) != SR_OK)
186 sr_err("Failed to start acquisition of device in "
187 "running session: %d", ret);
194 * Remove all datafeed callbacks in the current session.
196 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
198 SR_API int sr_session_datafeed_callback_remove_all(void)
201 sr_err("%s: session was NULL", __func__);
205 g_slist_free_full(session->datafeed_callbacks, g_free);
206 session->datafeed_callbacks = NULL;
212 * Add a datafeed callback to the current session.
214 * @param cb Function to call when a chunk of data is received.
216 * @param cb_data Opaque pointer passed in by the caller.
218 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
220 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb, void *cb_data)
222 struct datafeed_callback *cb_struct;
225 sr_err("%s: session was NULL", __func__);
230 sr_err("%s: cb was NULL", __func__);
234 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
235 return SR_ERR_MALLOC;
238 cb_struct->cb_data = cb_data;
240 session->datafeed_callbacks =
241 g_slist_append(session->datafeed_callbacks, cb_struct);
247 * Call every device in the session's callback.
249 * For sessions not driven by select loops such as sr_session_run(),
250 * but driven by another scheduler, this can be used to poll the devices
251 * from within that scheduler.
253 * @param block If TRUE, this call will wait for any of the session's
254 * sources to fire an event on the file descriptors, or
255 * any of their timeouts to activate. In other words, this
256 * can be used as a select loop.
257 * If FALSE, all sources have their callback run, regardless
258 * of file descriptor or timeout status.
260 * @return SR_OK upon success, SR_ERR on errors.
262 static int sr_session_iteration(gboolean block)
267 ret = g_poll(session->pollfds, session->num_sources,
268 block ? session->source_timeout : 0);
269 for (i = 0; i < session->num_sources; i++) {
270 if (session->pollfds[i].revents > 0 || (ret == 0
271 && session->source_timeout == session->sources[i].timeout)) {
273 * Invoke the source's callback on an event,
274 * or if the poll timed out and this source
275 * asked for that timeout.
277 if (!session->sources[i].cb(session->pollfds[i].fd,
278 session->pollfds[i].revents,
279 session->sources[i].cb_data))
280 sr_session_source_remove(session->sources[i].poll_object);
283 * We want to take as little time as possible to stop
284 * the session if we have been told to do so. Therefore,
285 * we check the flag after processing every source, not
286 * just once per main event loop.
288 g_mutex_lock(&session->stop_mutex);
289 if (session->abort_session) {
290 sr_session_stop_sync();
291 /* But once is enough. */
292 session->abort_session = FALSE;
294 g_mutex_unlock(&session->stop_mutex);
303 * There can only be one session at a time.
305 * @return SR_OK upon success, SR_ERR upon errors.
307 SR_API int sr_session_start(void)
309 struct sr_dev_inst *sdi;
314 sr_err("%s: session was NULL; a session must be "
315 "created before starting it.", __func__);
319 if (!session->devs) {
320 sr_err("%s: session->devs was NULL; a session "
321 "cannot be started without devices.", __func__);
325 sr_info("Starting.");
328 for (l = session->devs; l; l = l->next) {
330 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
331 sr_err("%s: could not start an acquisition "
332 "(%s)", __func__, sr_strerror(ret));
337 /* TODO: What if there are multiple devices? Which return code? */
345 * @return SR_OK upon success, SR_ERR_BUG upon errors.
347 SR_API int sr_session_run(void)
350 sr_err("%s: session was NULL; a session must be "
351 "created first, before running it.", __func__);
355 if (!session->devs) {
356 /* TODO: Actually the case? */
357 sr_err("%s: session->devs was NULL; a session "
358 "cannot be run without devices.", __func__);
361 session->running = TRUE;
365 /* Do we have real sources? */
366 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
367 /* Dummy source, freewheel over it. */
368 while (session->num_sources)
369 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
371 /* Real sources, use g_poll() main loop. */
372 while (session->num_sources)
373 sr_session_iteration(TRUE);
380 * Stop the current session.
382 * The current session is stopped immediately, with all acquisition sessions
383 * being stopped and hardware drivers cleaned up.
385 * This must be called from within the session thread, to prevent freeing
386 * resources that the session thread will try to use.
388 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
392 SR_PRIV int sr_session_stop_sync(void)
394 struct sr_dev_inst *sdi;
398 sr_err("%s: session was NULL", __func__);
402 sr_info("Stopping.");
404 for (l = session->devs; l; l = l->next) {
407 if (sdi->driver->dev_acquisition_stop)
408 sdi->driver->dev_acquisition_stop(sdi, sdi);
411 session->running = FALSE;
417 * Stop the current session.
419 * The current session is stopped immediately, with all acquisition sessions
420 * being stopped and hardware drivers cleaned up.
422 * If the session is run in a separate thread, this function will not block
423 * until the session is finished executing. It is the caller's responsibility
424 * to wait for the session thread to return before assuming that the session is
425 * completely decommissioned.
427 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
429 SR_API int sr_session_stop(void)
432 sr_err("%s: session was NULL", __func__);
436 g_mutex_lock(&session->stop_mutex);
437 session->abort_session = TRUE;
438 g_mutex_unlock(&session->stop_mutex);
446 * @param packet The packet to show debugging information for.
448 static void datafeed_dump(const struct sr_datafeed_packet *packet)
450 const struct sr_datafeed_logic *logic;
451 const struct sr_datafeed_analog *analog;
453 switch (packet->type) {
455 sr_dbg("bus: Received SR_DF_HEADER packet.");
458 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
461 sr_dbg("bus: Received SR_DF_META packet.");
464 logic = packet->payload;
465 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
469 analog = packet->payload;
470 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
471 analog->num_samples);
474 sr_dbg("bus: Received SR_DF_END packet.");
476 case SR_DF_FRAME_BEGIN:
477 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
479 case SR_DF_FRAME_END:
480 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
483 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
489 * Send a packet to whatever is listening on the datafeed bus.
491 * Hardware drivers use this to send a data packet to the frontend.
494 * @param packet The datafeed packet to send to the session bus.
496 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
500 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
501 const struct sr_datafeed_packet *packet)
504 struct datafeed_callback *cb_struct;
507 sr_err("%s: sdi was NULL", __func__);
512 sr_err("%s: packet was NULL", __func__);
516 for (l = session->datafeed_callbacks; l; l = l->next) {
517 if (sr_log_loglevel_get() >= SR_LOG_DBG)
518 datafeed_dump(packet);
520 cb_struct->cb(sdi, packet, cb_struct->cb_data);
527 * Add an event source for a file descriptor.
529 * @param pollfd The GPollFD.
530 * @param timeout Max time to wait before the callback is called, ignored if 0.
531 * @param cb Callback function to add. Must not be NULL.
532 * @param cb_data Data for the callback function. Can be NULL.
533 * @param poll_object TODO.
535 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
536 * SR_ERR_MALLOC upon memory allocation errors.
538 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
539 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
541 struct source *new_sources, *s;
542 GPollFD *new_pollfds;
545 sr_err("%s: cb was NULL", __func__);
549 /* Note: cb_data can be NULL, that's not a bug. */
551 new_pollfds = g_try_realloc(session->pollfds,
552 sizeof(GPollFD) * (session->num_sources + 1));
554 sr_err("%s: new_pollfds malloc failed", __func__);
555 return SR_ERR_MALLOC;
558 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
559 (session->num_sources + 1));
561 sr_err("%s: new_sources malloc failed", __func__);
562 return SR_ERR_MALLOC;
565 new_pollfds[session->num_sources] = *pollfd;
566 s = &new_sources[session->num_sources++];
567 s->timeout = timeout;
569 s->cb_data = cb_data;
570 s->poll_object = poll_object;
571 session->pollfds = new_pollfds;
572 session->sources = new_sources;
574 if (timeout != session->source_timeout && timeout > 0
575 && (session->source_timeout == -1 || timeout < session->source_timeout))
576 session->source_timeout = timeout;
582 * Add an event source for a file descriptor.
584 * @param fd The file descriptor.
585 * @param events Events to check for.
586 * @param timeout Max time to wait before the callback is called, ignored if 0.
587 * @param cb Callback function to add. Must not be NULL.
588 * @param cb_data Data for the callback function. Can be NULL.
590 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
591 * SR_ERR_MALLOC upon memory allocation errors.
593 SR_API int sr_session_source_add(int fd, int events, int timeout,
594 sr_receive_data_callback_t cb, void *cb_data)
601 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
605 * Add an event source for a GPollFD.
607 * @param pollfd The GPollFD.
608 * @param timeout Max time to wait before the callback is called, ignored if 0.
609 * @param cb Callback function to add. Must not be NULL.
610 * @param cb_data Data for the callback function. Can be NULL.
612 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
613 * SR_ERR_MALLOC upon memory allocation errors.
615 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
616 sr_receive_data_callback_t cb, void *cb_data)
618 return _sr_session_source_add(pollfd, timeout, cb,
619 cb_data, (gintptr)pollfd);
623 * Add an event source for a GIOChannel.
625 * @param channel The GIOChannel.
626 * @param events Events to poll on.
627 * @param timeout Max time to wait before the callback is called, ignored if 0.
628 * @param cb Callback function to add. Must not be NULL.
629 * @param cb_data Data for the callback function. Can be NULL.
631 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
632 * SR_ERR_MALLOC upon memory allocation errors.
634 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
635 int timeout, sr_receive_data_callback_t cb, void *cb_data)
640 g_io_channel_win32_make_pollfd(channel, events, &p);
642 p.fd = g_io_channel_unix_get_fd(channel);
646 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
650 * Remove the source belonging to the specified channel.
652 * @todo Add more error checks and logging.
654 * @param channel The channel for which the source should be removed.
656 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
657 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
660 static int _sr_session_source_remove(gintptr poll_object)
662 struct source *new_sources;
663 GPollFD *new_pollfds;
666 if (!session->sources || !session->num_sources) {
667 sr_err("%s: sources was NULL", __func__);
671 for (old = 0; old < session->num_sources; old++) {
672 if (session->sources[old].poll_object == poll_object)
676 /* fd not found, nothing to do */
677 if (old == session->num_sources)
680 session->num_sources -= 1;
682 if (old != session->num_sources) {
683 memmove(&session->pollfds[old], &session->pollfds[old+1],
684 (session->num_sources - old) * sizeof(GPollFD));
685 memmove(&session->sources[old], &session->sources[old+1],
686 (session->num_sources - old) * sizeof(struct source));
689 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
690 if (!new_pollfds && session->num_sources > 0) {
691 sr_err("%s: new_pollfds malloc failed", __func__);
692 return SR_ERR_MALLOC;
695 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
696 if (!new_sources && session->num_sources > 0) {
697 sr_err("%s: new_sources malloc failed", __func__);
698 return SR_ERR_MALLOC;
701 session->pollfds = new_pollfds;
702 session->sources = new_sources;
708 * Remove the source belonging to the specified file descriptor.
710 * @param fd The file descriptor for which the source should be removed.
712 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
713 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
716 SR_API int sr_session_source_remove(int fd)
718 return _sr_session_source_remove((gintptr)fd);
722 * Remove the source belonging to the specified poll descriptor.
724 * @param pollfd The poll descriptor for which the source should be removed.
726 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
727 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
730 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
732 return _sr_session_source_remove((gintptr)pollfd);
736 * Remove the source belonging to the specified channel.
738 * @param channel The channel for which the source should be removed.
740 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
741 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
744 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
746 return _sr_session_source_remove((gintptr)channel);