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->abort_session = FALSE;
88 g_mutex_init(&session->stop_mutex);
94 * Destroy the current session.
96 * This frees up all memory used by the session.
98 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
100 SR_API int sr_session_destroy(void)
103 sr_err("%s: session was NULL", __func__);
107 sr_session_dev_remove_all();
109 /* TODO: Error checks needed? */
111 g_mutex_clear(&session->stop_mutex);
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 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
127 SR_API int sr_session_dev_remove_all(void)
130 sr_err("%s: session was NULL", __func__);
134 g_slist_free(session->devs);
135 session->devs = NULL;
141 * Add a device instance to the current session.
143 * @param sdi The device instance to add to the current session. Must not
144 * be NULL. Also, sdi->driver and sdi->driver->dev_open must
147 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
149 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
153 sr_err("%s: sdi was NULL", __func__);
158 sr_err("%s: session was NULL", __func__);
162 /* If sdi->driver is NULL, this is a virtual device. */
164 sr_dbg("%s: sdi->driver was NULL, this seems to be "
165 "a virtual device; continuing", __func__);
166 /* Just add the device, don't run dev_open(). */
167 session->devs = g_slist_append(session->devs, (gpointer)sdi);
171 /* sdi->driver is non-NULL (i.e. we have a real device). */
172 if (!sdi->driver->dev_open) {
173 sr_err("%s: sdi->driver->dev_open was NULL", __func__);
177 session->devs = g_slist_append(session->devs, (gpointer)sdi);
183 * Remove all datafeed callbacks in the current session.
185 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
187 SR_API int sr_session_datafeed_callback_remove_all(void)
190 sr_err("%s: session was NULL", __func__);
194 g_slist_free_full(session->datafeed_callbacks, g_free);
195 session->datafeed_callbacks = NULL;
201 * Add a datafeed callback to the current session.
203 * @param cb Function to call when a chunk of data is received.
205 * @param cb_data Opaque pointer passed in by the caller.
207 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
209 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb, void *cb_data)
211 struct datafeed_callback *cb_struct;
214 sr_err("%s: session was NULL", __func__);
219 sr_err("%s: cb was NULL", __func__);
223 if (!(cb_struct = g_try_malloc0(sizeof(struct datafeed_callback))))
224 return SR_ERR_MALLOC;
227 cb_struct->cb_data = cb_data;
229 session->datafeed_callbacks =
230 g_slist_append(session->datafeed_callbacks, cb_struct);
236 * Call every device in the session's callback.
238 * For sessions not driven by select loops such as sr_session_run(),
239 * but driven by another scheduler, this can be used to poll the devices
240 * from within that scheduler.
242 * @param block If TRUE, this call will wait for any of the session's
243 * sources to fire an event on the file descriptors, or
244 * any of their timeouts to activate. In other words, this
245 * can be used as a select loop.
246 * If FALSE, all sources have their callback run, regardless
247 * of file descriptor or timeout status.
249 * @return SR_OK upon success, SR_ERR on errors.
251 static int sr_session_iteration(gboolean block)
256 ret = g_poll(session->pollfds, session->num_sources,
257 block ? session->source_timeout : 0);
258 for (i = 0; i < session->num_sources; i++) {
259 if (session->pollfds[i].revents > 0 || (ret == 0
260 && session->source_timeout == session->sources[i].timeout)) {
262 * Invoke the source's callback on an event,
263 * or if the poll timed out and this source
264 * asked for that timeout.
266 if (!session->sources[i].cb(session->pollfds[i].fd,
267 session->pollfds[i].revents,
268 session->sources[i].cb_data))
269 sr_session_source_remove(session->sources[i].poll_object);
272 * We want to take as little time as possible to stop
273 * the session if we have been told to do so. Therefore,
274 * we check the flag after processing every source, not
275 * just once per main event loop.
277 g_mutex_lock(&session->stop_mutex);
278 if (session->abort_session) {
279 sr_session_stop_sync();
280 /* But once is enough. */
281 session->abort_session = FALSE;
283 g_mutex_unlock(&session->stop_mutex);
292 * There can only be one session at a time.
294 * @return SR_OK upon success, SR_ERR upon errors.
296 SR_API int sr_session_start(void)
298 struct sr_dev_inst *sdi;
303 sr_err("%s: session was NULL; a session must be "
304 "created before starting it.", __func__);
308 if (!session->devs) {
309 sr_err("%s: session->devs was NULL; a session "
310 "cannot be started without devices.", __func__);
314 sr_info("Starting.");
317 for (l = session->devs; l; l = l->next) {
319 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
320 sr_err("%s: could not start an acquisition "
321 "(%d)", __func__, ret);
326 /* TODO: What if there are multiple devices? Which return code? */
334 * @return SR_OK upon success, SR_ERR_BUG upon errors.
336 SR_API int sr_session_run(void)
339 sr_err("%s: session was NULL; a session must be "
340 "created first, before running it.", __func__);
344 if (!session->devs) {
345 /* TODO: Actually the case? */
346 sr_err("%s: session->devs was NULL; a session "
347 "cannot be run without devices.", __func__);
353 /* Do we have real sources? */
354 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
355 /* Dummy source, freewheel over it. */
356 while (session->num_sources)
357 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
359 /* Real sources, use g_poll() main loop. */
360 while (session->num_sources)
361 sr_session_iteration(TRUE);
368 * Stop the current session.
370 * The current session is stopped immediately, with all acquisition sessions
371 * being stopped and hardware drivers cleaned up.
373 * This must be called from within the session thread, to prevent freeing
374 * resources that the session thread will try to use.
376 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
378 SR_PRIV int sr_session_stop_sync(void)
380 struct sr_dev_inst *sdi;
384 sr_err("%s: session was NULL", __func__);
388 sr_info("Stopping.");
390 for (l = session->devs; l; l = l->next) {
393 if (sdi->driver->dev_acquisition_stop)
394 sdi->driver->dev_acquisition_stop(sdi, sdi);
402 * Stop the current session.
404 * The current session is stopped immediately, with all acquisition sessions
405 * being stopped and hardware drivers cleaned up.
407 * If the session is run in a separate thread, this function will not block
408 * until the session is finished executing. It is the caller's responsibility
409 * to wait for the session thread to return before assuming that the session is
410 * completely decommissioned.
412 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
414 SR_API int sr_session_stop(void)
417 sr_err("%s: session was NULL", __func__);
421 g_mutex_lock(&session->stop_mutex);
422 session->abort_session = TRUE;
423 g_mutex_unlock(&session->stop_mutex);
431 * @param packet The packet to show debugging information for.
433 static void datafeed_dump(const struct sr_datafeed_packet *packet)
435 const struct sr_datafeed_logic *logic;
436 const struct sr_datafeed_analog *analog;
438 switch (packet->type) {
440 sr_dbg("bus: Received SR_DF_HEADER packet.");
443 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
446 sr_dbg("bus: Received SR_DF_META packet.");
449 logic = packet->payload;
450 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
454 analog = packet->payload;
455 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
456 analog->num_samples);
459 sr_dbg("bus: Received SR_DF_END packet.");
461 case SR_DF_FRAME_BEGIN:
462 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
464 case SR_DF_FRAME_END:
465 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
468 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
474 * Send a packet to whatever is listening on the datafeed bus.
476 * Hardware drivers use this to send a data packet to the frontend.
479 * @param packet The datafeed packet to send to the session bus.
481 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
485 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
486 const struct sr_datafeed_packet *packet)
489 struct datafeed_callback *cb_struct;
492 sr_err("%s: sdi was NULL", __func__);
497 sr_err("%s: packet was NULL", __func__);
501 for (l = session->datafeed_callbacks; l; l = l->next) {
502 if (sr_log_loglevel_get() >= SR_LOG_DBG)
503 datafeed_dump(packet);
505 cb_struct->cb(sdi, packet, cb_struct->cb_data);
512 * Add an event source for a file descriptor.
514 * @param pollfd The GPollFD.
515 * @param timeout Max time to wait before the callback is called, ignored if 0.
516 * @param cb Callback function to add. Must not be NULL.
517 * @param cb_data Data for the callback function. Can be NULL.
518 * @param poll_object TODO.
520 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
521 * SR_ERR_MALLOC upon memory allocation errors.
523 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
524 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
526 struct source *new_sources, *s;
527 GPollFD *new_pollfds;
530 sr_err("%s: cb was NULL", __func__);
534 /* Note: cb_data can be NULL, that's not a bug. */
536 new_pollfds = g_try_realloc(session->pollfds,
537 sizeof(GPollFD) * (session->num_sources + 1));
539 sr_err("%s: new_pollfds malloc failed", __func__);
540 return SR_ERR_MALLOC;
543 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
544 (session->num_sources + 1));
546 sr_err("%s: new_sources malloc failed", __func__);
547 return SR_ERR_MALLOC;
550 new_pollfds[session->num_sources] = *pollfd;
551 s = &new_sources[session->num_sources++];
552 s->timeout = timeout;
554 s->cb_data = cb_data;
555 s->poll_object = poll_object;
556 session->pollfds = new_pollfds;
557 session->sources = new_sources;
559 if (timeout != session->source_timeout && timeout > 0
560 && (session->source_timeout == -1 || timeout < session->source_timeout))
561 session->source_timeout = timeout;
567 * Add an event source for a file descriptor.
569 * @param fd The file descriptor.
570 * @param events Events to check for.
571 * @param timeout Max time to wait before the callback is called, ignored if 0.
572 * @param cb Callback function to add. Must not be NULL.
573 * @param cb_data Data for the callback function. Can be NULL.
575 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
576 * SR_ERR_MALLOC upon memory allocation errors.
578 SR_API int sr_session_source_add(int fd, int events, int timeout,
579 sr_receive_data_callback_t cb, void *cb_data)
586 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
590 * Add an event source for a GPollFD.
592 * @param pollfd The GPollFD.
593 * @param timeout Max time to wait before the callback is called, ignored if 0.
594 * @param cb Callback function to add. Must not be NULL.
595 * @param cb_data Data for the callback function. Can be NULL.
597 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
598 * SR_ERR_MALLOC upon memory allocation errors.
600 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
601 sr_receive_data_callback_t cb, void *cb_data)
603 return _sr_session_source_add(pollfd, timeout, cb,
604 cb_data, (gintptr)pollfd);
608 * Add an event source for a GIOChannel.
610 * @param channel The GIOChannel.
611 * @param events Events to poll on.
612 * @param timeout Max time to wait before the callback is called, ignored if 0.
613 * @param cb Callback function to add. Must not be NULL.
614 * @param cb_data Data for the callback function. Can be NULL.
616 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
617 * SR_ERR_MALLOC upon memory allocation errors.
619 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
620 int timeout, sr_receive_data_callback_t cb, void *cb_data)
625 g_io_channel_win32_make_pollfd(channel, events, &p);
627 p.fd = g_io_channel_unix_get_fd(channel);
631 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
635 * Remove the source belonging to the specified channel.
637 * @todo Add more error checks and logging.
639 * @param channel The channel for which the source should be removed.
641 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
642 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
645 static int _sr_session_source_remove(gintptr poll_object)
647 struct source *new_sources;
648 GPollFD *new_pollfds;
651 if (!session->sources || !session->num_sources) {
652 sr_err("%s: sources was NULL", __func__);
656 for (old = 0; old < session->num_sources; old++) {
657 if (session->sources[old].poll_object == poll_object)
661 /* fd not found, nothing to do */
662 if (old == session->num_sources)
665 session->num_sources -= 1;
667 if (old != session->num_sources) {
668 memmove(&session->pollfds[old], &session->pollfds[old+1],
669 (session->num_sources - old) * sizeof(GPollFD));
670 memmove(&session->sources[old], &session->sources[old+1],
671 (session->num_sources - old) * sizeof(struct source));
674 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
675 if (!new_pollfds && session->num_sources > 0) {
676 sr_err("%s: new_pollfds malloc failed", __func__);
677 return SR_ERR_MALLOC;
680 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
681 if (!new_sources && session->num_sources > 0) {
682 sr_err("%s: new_sources malloc failed", __func__);
683 return SR_ERR_MALLOC;
686 session->pollfds = new_pollfds;
687 session->sources = new_sources;
693 * Remove the source belonging to the specified file descriptor.
695 * @param fd The file descriptor for which the source should be removed.
697 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
698 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
701 SR_API int sr_session_source_remove(int fd)
703 return _sr_session_source_remove((gintptr)fd);
707 * Remove the source belonging to the specified poll descriptor.
709 * @param pollfd The poll descriptor for which the source should be removed.
711 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
712 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
715 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
717 return _sr_session_source_remove((gintptr)pollfd);
721 * Remove the source belonging to the specified channel.
723 * @param channel The channel for which the source should be removed.
725 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
726 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
729 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
731 return _sr_session_source_remove((gintptr)channel);