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 driver-specific prefix string. */
29 #define DRIVER_LOG_DOMAIN "session: "
30 #define sr_log(l, s, args...) sr_log(l, DRIVER_LOG_DOMAIN s, ## args)
31 #define sr_spew(s, args...) sr_spew(DRIVER_LOG_DOMAIN s, ## args)
32 #define sr_dbg(s, args...) sr_dbg(DRIVER_LOG_DOMAIN s, ## args)
33 #define sr_info(s, args...) sr_info(DRIVER_LOG_DOMAIN s, ## args)
34 #define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args)
35 #define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN 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_full(session->devs, (GDestroyNotify)sr_dev_close);
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 g_mutex_unlock(&session->stop_mutex);
275 * There can only be one session at a time.
277 * @return SR_OK upon success, SR_ERR upon errors.
279 SR_API int sr_session_start(void)
281 struct sr_dev_inst *sdi;
286 sr_err("%s: session was NULL; a session must be "
287 "created before starting it.", __func__);
291 if (!session->devs) {
292 sr_err("%s: session->devs was NULL; a session "
293 "cannot be started without devices.", __func__);
297 sr_info("Starting.");
300 for (l = session->devs; l; l = l->next) {
302 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
303 sr_err("%s: could not start an acquisition "
304 "(%d)", __func__, ret);
309 /* TODO: What if there are multiple devices? Which return code? */
317 * @return SR_OK upon success, SR_ERR_BUG upon errors.
319 SR_API int sr_session_run(void)
322 sr_err("%s: session was NULL; a session must be "
323 "created first, before running it.", __func__);
327 if (!session->devs) {
328 /* TODO: Actually the case? */
329 sr_err("%s: session->devs was NULL; a session "
330 "cannot be run without devices.", __func__);
336 /* Do we have real sources? */
337 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
338 /* Dummy source, freewheel over it. */
339 while (session->num_sources)
340 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
342 /* Real sources, use g_poll() main loop. */
343 sr_session_run_poll();
350 * Stop the current session.
352 * The current session is stopped immediately, with all acquisition sessions
353 * being stopped and hardware drivers cleaned up.
355 * This must be called from within the session thread, to prevent freeing
356 * resources that the session thread will try to use.
358 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
360 SR_PRIV int sr_session_stop_sync(void)
362 struct sr_dev_inst *sdi;
366 sr_err("%s: session was NULL", __func__);
370 sr_info("Stopping.");
372 for (l = session->devs; l; l = l->next) {
375 if (sdi->driver->dev_acquisition_stop)
376 sdi->driver->dev_acquisition_stop(sdi, sdi);
381 * Some sources may not be necessarily associated with a device.
382 * Those sources may still be present even after stopping all devices.
383 * We need to make sure all sources are removed, or we risk running the
384 * session in an infinite loop.
386 while (session->num_sources)
387 sr_session_source_remove(session->sources[0].poll_object);
393 * Stop the current session.
395 * The current session is stopped immediately, with all acquisition sessions
396 * being stopped and hardware drivers cleaned up.
398 * If the session is run in a separate thread, this function will not block
399 * until the session is finished executing. It is the caller's responsibility
400 * to wait for the session thread to return before assuming that the session is
401 * completely decommissioned.
403 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
405 SR_API int sr_session_stop(void)
408 sr_err("%s: session was NULL", __func__);
412 g_mutex_lock(&session->stop_mutex);
413 session->abort_session = TRUE;
414 g_mutex_unlock(&session->stop_mutex);
422 * @param packet The packet to show debugging information for.
424 static void datafeed_dump(const struct sr_datafeed_packet *packet)
426 const struct sr_datafeed_logic *logic;
427 const struct sr_datafeed_analog *analog;
429 switch (packet->type) {
431 sr_dbg("bus: Received SR_DF_HEADER packet.");
434 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
437 sr_dbg("bus: Received SR_DF_META packet.");
440 logic = packet->payload;
441 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
445 analog = packet->payload;
446 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
447 analog->num_samples);
450 sr_dbg("bus: Received SR_DF_END packet.");
452 case SR_DF_FRAME_BEGIN:
453 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
455 case SR_DF_FRAME_END:
456 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
459 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
465 * Send a packet to whatever is listening on the datafeed bus.
467 * Hardware drivers use this to send a data packet to the frontend.
470 * @param packet The datafeed packet to send to the session bus.
472 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
476 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
477 const struct sr_datafeed_packet *packet)
480 struct datafeed_callback *cb_struct;
483 sr_err("%s: sdi was NULL", __func__);
488 sr_err("%s: packet was NULL", __func__);
492 for (l = session->datafeed_callbacks; l; l = l->next) {
493 if (sr_log_loglevel_get() >= SR_LOG_DBG)
494 datafeed_dump(packet);
496 cb_struct->cb(sdi, packet, cb_struct->cb_data);
503 * Add an event source for a file descriptor.
505 * @param pollfd The GPollFD.
506 * @param timeout Max time to wait before the callback is called, ignored if 0.
507 * @param cb Callback function to add. Must not be NULL.
508 * @param cb_data Data for the callback function. Can be NULL.
509 * @param poll_object TODO.
511 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
512 * SR_ERR_MALLOC upon memory allocation errors.
514 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
515 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
517 struct source *new_sources, *s;
518 GPollFD *new_pollfds;
521 sr_err("%s: cb was NULL", __func__);
525 /* Note: cb_data can be NULL, that's not a bug. */
527 new_pollfds = g_try_realloc(session->pollfds,
528 sizeof(GPollFD) * (session->num_sources + 1));
530 sr_err("%s: new_pollfds malloc failed", __func__);
531 return SR_ERR_MALLOC;
534 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
535 (session->num_sources + 1));
537 sr_err("%s: new_sources malloc failed", __func__);
538 return SR_ERR_MALLOC;
541 new_pollfds[session->num_sources] = *pollfd;
542 s = &new_sources[session->num_sources++];
543 s->timeout = timeout;
545 s->cb_data = cb_data;
546 s->poll_object = poll_object;
547 session->pollfds = new_pollfds;
548 session->sources = new_sources;
550 if (timeout != session->source_timeout && timeout > 0
551 && (session->source_timeout == -1 || timeout < session->source_timeout))
552 session->source_timeout = timeout;
558 * Add an event source for a file descriptor.
560 * @param fd The file descriptor.
561 * @param events Events to check for.
562 * @param timeout Max time to wait before the callback is called, ignored if 0.
563 * @param cb Callback function to add. Must not be NULL.
564 * @param cb_data Data for the callback function. Can be NULL.
566 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
567 * SR_ERR_MALLOC upon memory allocation errors.
569 SR_API int sr_session_source_add(int fd, int events, int timeout,
570 sr_receive_data_callback_t cb, void *cb_data)
577 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
581 * Add an event source for a GPollFD.
583 * @param pollfd The GPollFD.
584 * @param timeout Max time to wait before the callback is called, ignored if 0.
585 * @param cb Callback function to add. Must not be NULL.
586 * @param cb_data Data for the callback function. Can be NULL.
588 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
589 * SR_ERR_MALLOC upon memory allocation errors.
591 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
592 sr_receive_data_callback_t cb, void *cb_data)
594 return _sr_session_source_add(pollfd, timeout, cb,
595 cb_data, (gintptr)pollfd);
599 * Add an event source for a GIOChannel.
601 * @param channel The GIOChannel.
602 * @param events Events to poll on.
603 * @param timeout Max time to wait before the callback is called, ignored if 0.
604 * @param cb Callback function to add. Must not be NULL.
605 * @param cb_data Data for the callback function. Can be NULL.
607 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
608 * SR_ERR_MALLOC upon memory allocation errors.
610 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
611 int timeout, sr_receive_data_callback_t cb, void *cb_data)
616 g_io_channel_win32_make_pollfd(channel, events, &p);
618 p.fd = g_io_channel_unix_get_fd(channel);
622 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
626 * Remove the source belonging to the specified channel.
628 * @todo Add more error checks and logging.
630 * @param channel The channel for which the source should be removed.
632 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
633 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
636 static int _sr_session_source_remove(gintptr poll_object)
638 struct source *new_sources;
639 GPollFD *new_pollfds;
642 if (!session->sources || !session->num_sources) {
643 sr_err("%s: sources was NULL", __func__);
647 for (old = 0; old < session->num_sources; old++) {
648 if (session->sources[old].poll_object == poll_object)
652 /* fd not found, nothing to do */
653 if (old == session->num_sources)
656 session->num_sources -= 1;
658 if (old != session->num_sources) {
659 memmove(&session->pollfds[old], &session->pollfds[old+1],
660 (session->num_sources - old) * sizeof(GPollFD));
661 memmove(&session->sources[old], &session->sources[old+1],
662 (session->num_sources - old) * sizeof(struct source));
665 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
666 if (!new_pollfds && session->num_sources > 0) {
667 sr_err("%s: new_pollfds malloc failed", __func__);
668 return SR_ERR_MALLOC;
671 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
672 if (!new_sources && session->num_sources > 0) {
673 sr_err("%s: new_sources malloc failed", __func__);
674 return SR_ERR_MALLOC;
677 session->pollfds = new_pollfds;
678 session->sources = new_sources;
684 * Remove the source belonging to the specified file descriptor.
686 * @param fd The file descriptor for which the source should be removed.
688 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
689 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
692 SR_API int sr_session_source_remove(int fd)
694 return _sr_session_source_remove((gintptr)fd);
698 * Remove the source belonging to the specified poll descriptor.
700 * @param pollfd The poll descriptor for which the source should be removed.
702 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
703 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
706 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
708 return _sr_session_source_remove((gintptr)pollfd);
712 * Remove the source belonging to the specified channel.
714 * @param channel The channel for which the source should be removed.
716 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
717 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
720 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
722 return _sr_session_source_remove((gintptr)channel);