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);
235 static int sr_session_run_poll(void)
240 while (session->num_sources > 0) {
241 ret = g_poll(session->pollfds, session->num_sources,
242 session->source_timeout);
243 for (i = 0; i < session->num_sources; i++) {
244 if (session->pollfds[i].revents > 0 || (ret == 0
245 && session->source_timeout == session->sources[i].timeout)) {
247 * Invoke the source's callback on an event,
248 * or if the poll timed out and this source
249 * asked for that timeout.
251 if (!session->sources[i].cb(session->pollfds[i].fd,
252 session->pollfds[i].revents,
253 session->sources[i].cb_data))
254 sr_session_source_remove(session->sources[i].poll_object);
257 * We want to take as little time as possible to stop
258 * the session if we have been told to do so. Therefore,
259 * we check the flag after processing every source, not
260 * just once per main event loop.
262 g_mutex_lock(&session->stop_mutex);
263 if (session->abort_session) {
264 sr_session_stop_sync();
265 /* But once is enough. */
266 session->abort_session = FALSE;
268 g_mutex_unlock(&session->stop_mutex);
278 * There can only be one session at a time.
280 * @return SR_OK upon success, SR_ERR upon errors.
282 SR_API int sr_session_start(void)
284 struct sr_dev_inst *sdi;
289 sr_err("%s: session was NULL; a session must be "
290 "created before starting it.", __func__);
294 if (!session->devs) {
295 sr_err("%s: session->devs was NULL; a session "
296 "cannot be started without devices.", __func__);
300 sr_info("Starting.");
303 for (l = session->devs; l; l = l->next) {
305 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
306 sr_err("%s: could not start an acquisition "
307 "(%d)", __func__, ret);
312 /* TODO: What if there are multiple devices? Which return code? */
320 * @return SR_OK upon success, SR_ERR_BUG upon errors.
322 SR_API int sr_session_run(void)
325 sr_err("%s: session was NULL; a session must be "
326 "created first, before running it.", __func__);
330 if (!session->devs) {
331 /* TODO: Actually the case? */
332 sr_err("%s: session->devs was NULL; a session "
333 "cannot be run without devices.", __func__);
339 /* Do we have real sources? */
340 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
341 /* Dummy source, freewheel over it. */
342 while (session->num_sources)
343 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
345 /* Real sources, use g_poll() main loop. */
346 sr_session_run_poll();
353 * Stop the current session.
355 * The current session is stopped immediately, with all acquisition sessions
356 * being stopped and hardware drivers cleaned up.
358 * This must be called from within the session thread, to prevent freeing
359 * resources that the session thread will try to use.
361 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
363 SR_PRIV int sr_session_stop_sync(void)
365 struct sr_dev_inst *sdi;
369 sr_err("%s: session was NULL", __func__);
373 sr_info("Stopping.");
375 for (l = session->devs; l; l = l->next) {
378 if (sdi->driver->dev_acquisition_stop)
379 sdi->driver->dev_acquisition_stop(sdi, sdi);
387 * Stop the current session.
389 * The current session is stopped immediately, with all acquisition sessions
390 * being stopped and hardware drivers cleaned up.
392 * If the session is run in a separate thread, this function will not block
393 * until the session is finished executing. It is the caller's responsibility
394 * to wait for the session thread to return before assuming that the session is
395 * completely decommissioned.
397 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
399 SR_API int sr_session_stop(void)
402 sr_err("%s: session was NULL", __func__);
406 g_mutex_lock(&session->stop_mutex);
407 session->abort_session = TRUE;
408 g_mutex_unlock(&session->stop_mutex);
416 * @param packet The packet to show debugging information for.
418 static void datafeed_dump(const struct sr_datafeed_packet *packet)
420 const struct sr_datafeed_logic *logic;
421 const struct sr_datafeed_analog *analog;
423 switch (packet->type) {
425 sr_dbg("bus: Received SR_DF_HEADER packet.");
428 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
431 sr_dbg("bus: Received SR_DF_META packet.");
434 logic = packet->payload;
435 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
439 analog = packet->payload;
440 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
441 analog->num_samples);
444 sr_dbg("bus: Received SR_DF_END packet.");
446 case SR_DF_FRAME_BEGIN:
447 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
449 case SR_DF_FRAME_END:
450 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
453 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
459 * Send a packet to whatever is listening on the datafeed bus.
461 * Hardware drivers use this to send a data packet to the frontend.
464 * @param packet The datafeed packet to send to the session bus.
466 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
470 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
471 const struct sr_datafeed_packet *packet)
474 struct datafeed_callback *cb_struct;
477 sr_err("%s: sdi was NULL", __func__);
482 sr_err("%s: packet was NULL", __func__);
486 for (l = session->datafeed_callbacks; l; l = l->next) {
487 if (sr_log_loglevel_get() >= SR_LOG_DBG)
488 datafeed_dump(packet);
490 cb_struct->cb(sdi, packet, cb_struct->cb_data);
497 * Add an event source for a file descriptor.
499 * @param pollfd The GPollFD.
500 * @param timeout Max time to wait before the callback is called, ignored if 0.
501 * @param cb Callback function to add. Must not be NULL.
502 * @param cb_data Data for the callback function. Can be NULL.
503 * @param poll_object TODO.
505 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
506 * SR_ERR_MALLOC upon memory allocation errors.
508 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
509 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
511 struct source *new_sources, *s;
512 GPollFD *new_pollfds;
515 sr_err("%s: cb was NULL", __func__);
519 /* Note: cb_data can be NULL, that's not a bug. */
521 new_pollfds = g_try_realloc(session->pollfds,
522 sizeof(GPollFD) * (session->num_sources + 1));
524 sr_err("%s: new_pollfds malloc failed", __func__);
525 return SR_ERR_MALLOC;
528 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
529 (session->num_sources + 1));
531 sr_err("%s: new_sources malloc failed", __func__);
532 return SR_ERR_MALLOC;
535 new_pollfds[session->num_sources] = *pollfd;
536 s = &new_sources[session->num_sources++];
537 s->timeout = timeout;
539 s->cb_data = cb_data;
540 s->poll_object = poll_object;
541 session->pollfds = new_pollfds;
542 session->sources = new_sources;
544 if (timeout != session->source_timeout && timeout > 0
545 && (session->source_timeout == -1 || timeout < session->source_timeout))
546 session->source_timeout = timeout;
552 * Add an event source for a file descriptor.
554 * @param fd The file descriptor.
555 * @param events Events to check for.
556 * @param timeout Max time to wait before the callback is called, ignored if 0.
557 * @param cb Callback function to add. Must not be NULL.
558 * @param cb_data Data for the callback function. Can be NULL.
560 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
561 * SR_ERR_MALLOC upon memory allocation errors.
563 SR_API int sr_session_source_add(int fd, int events, int timeout,
564 sr_receive_data_callback_t cb, void *cb_data)
571 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
575 * Add an event source for a GPollFD.
577 * @param pollfd The GPollFD.
578 * @param timeout Max time to wait before the callback is called, ignored if 0.
579 * @param cb Callback function to add. Must not be NULL.
580 * @param cb_data Data for the callback function. Can be NULL.
582 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
583 * SR_ERR_MALLOC upon memory allocation errors.
585 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
586 sr_receive_data_callback_t cb, void *cb_data)
588 return _sr_session_source_add(pollfd, timeout, cb,
589 cb_data, (gintptr)pollfd);
593 * Add an event source for a GIOChannel.
595 * @param channel The GIOChannel.
596 * @param events Events to poll on.
597 * @param timeout Max time to wait before the callback is called, ignored if 0.
598 * @param cb Callback function to add. Must not be NULL.
599 * @param cb_data Data for the callback function. Can be NULL.
601 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
602 * SR_ERR_MALLOC upon memory allocation errors.
604 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
605 int timeout, sr_receive_data_callback_t cb, void *cb_data)
610 g_io_channel_win32_make_pollfd(channel, events, &p);
612 p.fd = g_io_channel_unix_get_fd(channel);
616 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
620 * Remove the source belonging to the specified channel.
622 * @todo Add more error checks and logging.
624 * @param channel The channel for which the source should be removed.
626 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
627 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
630 static int _sr_session_source_remove(gintptr poll_object)
632 struct source *new_sources;
633 GPollFD *new_pollfds;
636 if (!session->sources || !session->num_sources) {
637 sr_err("%s: sources was NULL", __func__);
641 for (old = 0; old < session->num_sources; old++) {
642 if (session->sources[old].poll_object == poll_object)
646 /* fd not found, nothing to do */
647 if (old == session->num_sources)
650 session->num_sources -= 1;
652 if (old != session->num_sources) {
653 memmove(&session->pollfds[old], &session->pollfds[old+1],
654 (session->num_sources - old) * sizeof(GPollFD));
655 memmove(&session->sources[old], &session->sources[old+1],
656 (session->num_sources - old) * sizeof(struct source));
659 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
660 if (!new_pollfds && session->num_sources > 0) {
661 sr_err("%s: new_pollfds malloc failed", __func__);
662 return SR_ERR_MALLOC;
665 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
666 if (!new_sources && session->num_sources > 0) {
667 sr_err("%s: new_sources malloc failed", __func__);
668 return SR_ERR_MALLOC;
671 session->pollfds = new_pollfds;
672 session->sources = new_sources;
678 * Remove the source belonging to the specified file descriptor.
680 * @param fd The file descriptor for which the source should be removed.
682 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
683 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
686 SR_API int sr_session_source_remove(int fd)
688 return _sr_session_source_remove((gintptr)fd);
692 * Remove the source belonging to the specified poll descriptor.
694 * @param pollfd The poll descriptor for which the source should be removed.
696 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
697 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
700 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
702 return _sr_session_source_remove((gintptr)pollfd);
706 * Remove the source belonging to the specified channel.
708 * @param channel The channel for which the source should be removed.
710 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
711 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
714 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
716 return _sr_session_source_remove((gintptr)channel);