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 * List all device instances attached to the current session.
196 * @param devlist A pointer where the device instance list will be
197 * stored on return. If no devices are in the session,
198 * this will be NULL. Each element in the list points
199 * to a struct sr_dev_inst *.
200 * The list must be freed by the caller, but not the
201 * elements pointed to.
203 * @return SR_OK upon success, SR_ERR upon invalid arguments.
205 SR_API int sr_session_dev_list(GSList **devlist)
213 *devlist = g_slist_copy(session->devs);
219 * Remove all datafeed callbacks in the current session.
221 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
223 SR_API int sr_session_datafeed_callback_remove_all(void)
226 sr_err("%s: session was NULL", __func__);
230 g_slist_free_full(session->datafeed_callbacks, g_free);
231 session->datafeed_callbacks = NULL;
237 * Add a datafeed callback to the current session.
239 * @param cb Function to call when a chunk of data is received.
241 * @param cb_data Opaque pointer passed in by the caller.
243 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
245 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb, void *cb_data)
247 struct datafeed_callback *cb_struct;
250 sr_err("%s: session was NULL", __func__);
255 sr_err("%s: cb was NULL", __func__);
259 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
260 return SR_ERR_MALLOC;
263 cb_struct->cb_data = cb_data;
265 session->datafeed_callbacks =
266 g_slist_append(session->datafeed_callbacks, cb_struct);
272 * Call every device in the session's callback.
274 * For sessions not driven by select loops such as sr_session_run(),
275 * but driven by another scheduler, this can be used to poll the devices
276 * from within that scheduler.
278 * @param block If TRUE, this call will wait for any of the session's
279 * sources to fire an event on the file descriptors, or
280 * any of their timeouts to activate. In other words, this
281 * can be used as a select loop.
282 * If FALSE, all sources have their callback run, regardless
283 * of file descriptor or timeout status.
285 * @return SR_OK upon success, SR_ERR on errors.
287 static int sr_session_iteration(gboolean block)
292 ret = g_poll(session->pollfds, session->num_sources,
293 block ? session->source_timeout : 0);
294 for (i = 0; i < session->num_sources; i++) {
295 if (session->pollfds[i].revents > 0 || (ret == 0
296 && session->source_timeout == session->sources[i].timeout)) {
298 * Invoke the source's callback on an event,
299 * or if the poll timed out and this source
300 * asked for that timeout.
302 if (!session->sources[i].cb(session->pollfds[i].fd,
303 session->pollfds[i].revents,
304 session->sources[i].cb_data))
305 sr_session_source_remove(session->sources[i].poll_object);
308 * We want to take as little time as possible to stop
309 * the session if we have been told to do so. Therefore,
310 * we check the flag after processing every source, not
311 * just once per main event loop.
313 g_mutex_lock(&session->stop_mutex);
314 if (session->abort_session) {
315 sr_session_stop_sync();
316 /* But once is enough. */
317 session->abort_session = FALSE;
319 g_mutex_unlock(&session->stop_mutex);
328 * There can only be one session at a time.
330 * @return SR_OK upon success, SR_ERR upon errors.
332 SR_API int sr_session_start(void)
334 struct sr_dev_inst *sdi;
339 sr_err("%s: session was NULL; a session must be "
340 "created before starting it.", __func__);
344 if (!session->devs) {
345 sr_err("%s: session->devs was NULL; a session "
346 "cannot be started without devices.", __func__);
350 sr_info("Starting.");
353 for (l = session->devs; l; l = l->next) {
355 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
356 sr_err("%s: could not start an acquisition "
357 "(%s)", __func__, sr_strerror(ret));
362 /* TODO: What if there are multiple devices? Which return code? */
370 * @return SR_OK upon success, SR_ERR_BUG upon errors.
372 SR_API int sr_session_run(void)
375 sr_err("%s: session was NULL; a session must be "
376 "created first, before running it.", __func__);
380 if (!session->devs) {
381 /* TODO: Actually the case? */
382 sr_err("%s: session->devs was NULL; a session "
383 "cannot be run without devices.", __func__);
386 session->running = TRUE;
390 /* Do we have real sources? */
391 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
392 /* Dummy source, freewheel over it. */
393 while (session->num_sources)
394 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
396 /* Real sources, use g_poll() main loop. */
397 while (session->num_sources)
398 sr_session_iteration(TRUE);
405 * Stop the current session.
407 * The current session is stopped immediately, with all acquisition sessions
408 * being stopped and hardware drivers cleaned up.
410 * This must be called from within the session thread, to prevent freeing
411 * resources that the session thread will try to use.
413 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
417 SR_PRIV int sr_session_stop_sync(void)
419 struct sr_dev_inst *sdi;
423 sr_err("%s: session was NULL", __func__);
427 sr_info("Stopping.");
429 for (l = session->devs; l; l = l->next) {
432 if (sdi->driver->dev_acquisition_stop)
433 sdi->driver->dev_acquisition_stop(sdi, sdi);
436 session->running = FALSE;
442 * Stop the current session.
444 * The current session is stopped immediately, with all acquisition sessions
445 * being stopped and hardware drivers cleaned up.
447 * If the session is run in a separate thread, this function will not block
448 * until the session is finished executing. It is the caller's responsibility
449 * to wait for the session thread to return before assuming that the session is
450 * completely decommissioned.
452 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
454 SR_API int sr_session_stop(void)
457 sr_err("%s: session was NULL", __func__);
461 g_mutex_lock(&session->stop_mutex);
462 session->abort_session = TRUE;
463 g_mutex_unlock(&session->stop_mutex);
471 * @param packet The packet to show debugging information for.
473 static void datafeed_dump(const struct sr_datafeed_packet *packet)
475 const struct sr_datafeed_logic *logic;
476 const struct sr_datafeed_analog *analog;
478 switch (packet->type) {
480 sr_dbg("bus: Received SR_DF_HEADER packet.");
483 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
486 sr_dbg("bus: Received SR_DF_META packet.");
489 logic = packet->payload;
490 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
494 analog = packet->payload;
495 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
496 analog->num_samples);
499 sr_dbg("bus: Received SR_DF_END packet.");
501 case SR_DF_FRAME_BEGIN:
502 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
504 case SR_DF_FRAME_END:
505 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
508 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
514 * Send a packet to whatever is listening on the datafeed bus.
516 * Hardware drivers use this to send a data packet to the frontend.
519 * @param packet The datafeed packet to send to the session bus.
521 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
525 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
526 const struct sr_datafeed_packet *packet)
529 struct datafeed_callback *cb_struct;
532 sr_err("%s: sdi was NULL", __func__);
537 sr_err("%s: packet was NULL", __func__);
541 for (l = session->datafeed_callbacks; l; l = l->next) {
542 if (sr_log_loglevel_get() >= SR_LOG_DBG)
543 datafeed_dump(packet);
545 cb_struct->cb(sdi, packet, cb_struct->cb_data);
552 * Add an event source for a file descriptor.
554 * @param pollfd The GPollFD.
555 * @param timeout Max time to wait before the callback is called, ignored if 0.
556 * @param cb Callback function to add. Must not be NULL.
557 * @param cb_data Data for the callback function. Can be NULL.
558 * @param poll_object TODO.
560 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
561 * SR_ERR_MALLOC upon memory allocation errors.
563 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
564 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
566 struct source *new_sources, *s;
567 GPollFD *new_pollfds;
570 sr_err("%s: cb was NULL", __func__);
574 /* Note: cb_data can be NULL, that's not a bug. */
576 new_pollfds = g_try_realloc(session->pollfds,
577 sizeof(GPollFD) * (session->num_sources + 1));
579 sr_err("%s: new_pollfds malloc failed", __func__);
580 return SR_ERR_MALLOC;
583 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
584 (session->num_sources + 1));
586 sr_err("%s: new_sources malloc failed", __func__);
587 return SR_ERR_MALLOC;
590 new_pollfds[session->num_sources] = *pollfd;
591 s = &new_sources[session->num_sources++];
592 s->timeout = timeout;
594 s->cb_data = cb_data;
595 s->poll_object = poll_object;
596 session->pollfds = new_pollfds;
597 session->sources = new_sources;
599 if (timeout != session->source_timeout && timeout > 0
600 && (session->source_timeout == -1 || timeout < session->source_timeout))
601 session->source_timeout = timeout;
607 * Add an event source for a file descriptor.
609 * @param fd The file descriptor.
610 * @param events Events to check for.
611 * @param timeout Max time to wait before the callback is called, ignored if 0.
612 * @param cb Callback function to add. Must not be NULL.
613 * @param cb_data Data for the callback function. Can be NULL.
615 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
616 * SR_ERR_MALLOC upon memory allocation errors.
618 SR_API int sr_session_source_add(int fd, int events, int timeout,
619 sr_receive_data_callback_t cb, void *cb_data)
626 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
630 * Add an event source for a GPollFD.
632 * @param pollfd The GPollFD.
633 * @param timeout Max time to wait before the callback is called, ignored if 0.
634 * @param cb Callback function to add. Must not be NULL.
635 * @param cb_data Data for the callback function. Can be NULL.
637 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
638 * SR_ERR_MALLOC upon memory allocation errors.
640 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
641 sr_receive_data_callback_t cb, void *cb_data)
643 return _sr_session_source_add(pollfd, timeout, cb,
644 cb_data, (gintptr)pollfd);
648 * Add an event source for a GIOChannel.
650 * @param channel The GIOChannel.
651 * @param events Events to poll on.
652 * @param timeout Max time to wait before the callback is called, ignored if 0.
653 * @param cb Callback function to add. Must not be NULL.
654 * @param cb_data Data for the callback function. Can be NULL.
656 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
657 * SR_ERR_MALLOC upon memory allocation errors.
659 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
660 int timeout, sr_receive_data_callback_t cb, void *cb_data)
665 g_io_channel_win32_make_pollfd(channel, events, &p);
667 p.fd = g_io_channel_unix_get_fd(channel);
671 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
675 * Remove the source belonging to the specified channel.
677 * @todo Add more error checks and logging.
679 * @param channel The channel for which the source should be removed.
681 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
682 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
685 static int _sr_session_source_remove(gintptr poll_object)
687 struct source *new_sources;
688 GPollFD *new_pollfds;
691 if (!session->sources || !session->num_sources) {
692 sr_err("%s: sources was NULL", __func__);
696 for (old = 0; old < session->num_sources; old++) {
697 if (session->sources[old].poll_object == poll_object)
701 /* fd not found, nothing to do */
702 if (old == session->num_sources)
705 session->num_sources -= 1;
707 if (old != session->num_sources) {
708 memmove(&session->pollfds[old], &session->pollfds[old+1],
709 (session->num_sources - old) * sizeof(GPollFD));
710 memmove(&session->sources[old], &session->sources[old+1],
711 (session->num_sources - old) * sizeof(struct source));
714 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
715 if (!new_pollfds && session->num_sources > 0) {
716 sr_err("%s: new_pollfds malloc failed", __func__);
717 return SR_ERR_MALLOC;
720 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
721 if (!new_sources && session->num_sources > 0) {
722 sr_err("%s: new_sources malloc failed", __func__);
723 return SR_ERR_MALLOC;
726 session->pollfds = new_pollfds;
727 session->sources = new_sources;
733 * Remove the source belonging to the specified file descriptor.
735 * @param fd The file descriptor for which the source should be removed.
737 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
738 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
741 SR_API int sr_session_source_remove(int fd)
743 return _sr_session_source_remove((gintptr)fd);
747 * Remove the source belonging to the specified poll descriptor.
749 * @param pollfd The poll descriptor for which the source should be removed.
751 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
752 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
755 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
757 return _sr_session_source_remove((gintptr)pollfd);
761 * Remove the source belonging to the specified channel.
763 * @param channel The channel for which the source should be removed.
765 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
766 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
769 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
771 return _sr_session_source_remove((gintptr)channel);