2 * This file is part of the sigrok 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"
31 * Creating, using, or destroying libsigrok sessions.
35 * @defgroup grp_session Session handling
37 * Creating, using, or destroying libsigrok sessions.
44 sr_receive_data_callback_t cb;
47 /* This is used to keep track of the object (fd, pollfd or channel) which is
48 * being polled and will be used to match the source when removing it again.
53 /* There can only be one session at a time. */
54 /* 'session' is not static, it's used elsewhere (via 'extern'). */
55 struct sr_session *session;
58 * Create a new session.
60 * @todo Should it use the file-global "session" variable or take an argument?
61 * The same question applies to all the other session functions.
63 * @return A pointer to the newly allocated session, or NULL upon errors.
65 SR_API struct sr_session *sr_session_new(void)
67 if (!(session = g_try_malloc0(sizeof(struct sr_session)))) {
68 sr_err("session: %s: session malloc failed", __func__);
69 return NULL; /* TODO: SR_ERR_MALLOC? */
72 session->source_timeout = -1;
78 * Destroy the current session.
80 * This frees up all memory used by the session.
82 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
84 SR_API int sr_session_destroy(void)
87 sr_err("session: %s: session was NULL", __func__);
91 sr_session_dev_remove_all();
93 /* TODO: Error checks needed? */
101 static void sr_dev_close(struct sr_dev_inst *sdi)
103 if (sdi->driver && sdi->driver->dev_close)
104 sdi->driver->dev_close(sdi);
108 * Remove all the devices from the current session.
110 * The session itself (i.e., the struct sr_session) is not free'd and still
111 * exists after this function returns.
113 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
115 SR_API int sr_session_dev_remove_all(void)
118 sr_err("session: %s: session was NULL", __func__);
122 g_slist_free_full(session->devs, (GDestroyNotify)sr_dev_close);
123 session->devs = NULL;
129 * Add a device instance to the current session.
131 * @param sdi The device instance to add to the current session. Must not
132 * be NULL. Also, sdi->driver and sdi->driver->dev_open must
135 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
137 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
142 sr_err("session: %s: sdi was NULL", __func__);
147 sr_err("session: %s: session was NULL", __func__);
151 /* If sdi->driver is NULL, this is a virtual device. */
153 sr_dbg("session: %s: sdi->driver was NULL, this seems to be "
154 "a virtual device; continuing", __func__);
155 /* Just add the device, don't run dev_open(). */
156 session->devs = g_slist_append(session->devs, (gpointer)sdi);
160 /* sdi->driver is non-NULL (i.e. we have a real device). */
161 if (!sdi->driver->dev_open) {
162 sr_err("session: %s: sdi->driver->dev_open was NULL", __func__);
166 if ((ret = sdi->driver->dev_open((struct sr_dev_inst *)sdi)) != SR_OK) {
167 sr_err("session: %s: dev_open failed (%d)", __func__, ret);
171 session->devs = g_slist_append(session->devs, (gpointer)sdi);
177 * Remove all datafeed callbacks in the current session.
179 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
181 SR_API int sr_session_datafeed_callback_remove_all(void)
184 sr_err("session: %s: session was NULL", __func__);
188 g_slist_free(session->datafeed_callbacks);
189 session->datafeed_callbacks = NULL;
195 * Add a datafeed callback to the current session.
197 * @param cb Function to call when a chunk of data is received.
200 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
202 SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb)
205 sr_err("session: %s: session was NULL", __func__);
210 sr_err("session: %s: cb was NULL", __func__);
214 session->datafeed_callbacks =
215 g_slist_append(session->datafeed_callbacks, cb);
220 static int sr_session_run_poll(void)
225 while (session->num_sources > 0) {
226 ret = g_poll(session->pollfds, session->num_sources,
227 session->source_timeout);
228 for (i = 0; i < session->num_sources; i++) {
229 if (session->pollfds[i].revents > 0 || (ret == 0
230 && session->source_timeout == session->sources[i].timeout)) {
232 * Invoke the source's callback on an event,
233 * or if the poll timed out and this source
234 * asked for that timeout.
236 if (!session->sources[i].cb(session->pollfds[i].fd,
237 session->pollfds[i].revents,
238 session->sources[i].cb_data))
239 sr_session_source_remove(session->sources[i].poll_object);
250 * There can only be one session at a time.
252 * @return SR_OK upon success, SR_ERR upon errors.
254 SR_API int sr_session_start(void)
256 struct sr_dev_inst *sdi;
261 sr_err("session: %s: session was NULL; a session must be "
262 "created before starting it.", __func__);
266 if (!session->devs) {
267 sr_err("session: %s: session->devs was NULL; a session "
268 "cannot be started without devices.", __func__);
272 sr_info("session: starting");
275 for (l = session->devs; l; l = l->next) {
277 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
278 sr_err("session: %s: could not start an acquisition "
279 "(%d)", __func__, ret);
284 /* TODO: What if there are multiple devices? Which return code? */
292 * @return SR_OK upon success, SR_ERR_BUG upon errors.
294 SR_API int sr_session_run(void)
297 sr_err("session: %s: session was NULL; a session must be "
298 "created first, before running it.", __func__);
302 if (!session->devs) {
303 /* TODO: Actually the case? */
304 sr_err("session: %s: session->devs was NULL; a session "
305 "cannot be run without devices.", __func__);
309 sr_info("session: running");
311 /* Do we have real sources? */
312 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
313 /* Dummy source, freewheel over it. */
314 while (session->num_sources)
315 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
317 /* Real sources, use g_poll() main loop. */
318 sr_session_run_poll();
325 * Halt the current session.
327 * This function is deprecated and should not be used in new code, use
328 * sr_session_stop() instead. The behaviour of this function is identical to
331 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
333 SR_API int sr_session_halt(void)
335 return sr_session_stop();
339 * Stop the current session.
341 * The current session is stopped immediately, with all acquisition sessions
342 * being stopped and hardware drivers cleaned up.
344 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
346 SR_API int sr_session_stop(void)
348 struct sr_dev_inst *sdi;
352 sr_err("session: %s: session was NULL", __func__);
356 sr_info("session: stopping");
358 for (l = session->devs; l; l = l->next) {
361 if (sdi->driver->dev_acquisition_stop)
362 sdi->driver->dev_acquisition_stop(sdi, sdi);
367 * Some sources may not be necessarily associated with a device.
368 * Those sources may still be present even after stopping all devices.
369 * We need to make sure all sources are removed, or we risk running the
370 * session in an infinite loop.
372 while (session->num_sources)
373 sr_session_source_remove(session->sources[0].poll_object);
381 * @param packet The packet to show debugging information for.
383 static void datafeed_dump(const struct sr_datafeed_packet *packet)
385 const struct sr_datafeed_logic *logic;
386 const struct sr_datafeed_analog *analog;
388 switch (packet->type) {
390 sr_dbg("bus: received SR_DF_HEADER");
393 sr_dbg("bus: received SR_DF_TRIGGER");
395 case SR_DF_META_LOGIC:
396 sr_dbg("bus: received SR_DF_META_LOGIC");
399 logic = packet->payload;
400 /* TODO: Check for logic != NULL. */
401 sr_dbg("bus: received SR_DF_LOGIC %" PRIu64 " bytes", logic->length);
403 case SR_DF_META_ANALOG:
404 sr_dbg("bus: received SR_DF_META_ANALOG");
407 analog = packet->payload;
408 /* TODO: Check for analog != NULL. */
409 sr_dbg("bus: received SR_DF_ANALOG %d samples", analog->num_samples);
412 sr_dbg("bus: received SR_DF_END");
414 case SR_DF_FRAME_BEGIN:
415 sr_dbg("bus: received SR_DF_FRAME_BEGIN");
417 case SR_DF_FRAME_END:
418 sr_dbg("bus: received SR_DF_FRAME_END");
421 sr_dbg("bus: received unknown packet type %d", packet->type);
427 * Send a packet to whatever is listening on the datafeed bus.
429 * Hardware drivers use this to send a data packet to the frontend.
432 * @param packet The datafeed packet to send to the session bus.
434 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
438 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
439 const struct sr_datafeed_packet *packet)
442 sr_datafeed_callback_t cb;
445 sr_err("session: %s: sdi was NULL", __func__);
450 sr_err("session: %s: packet was NULL", __func__);
454 for (l = session->datafeed_callbacks; l; l = l->next) {
455 if (sr_log_loglevel_get() >= SR_LOG_DBG)
456 datafeed_dump(packet);
465 * Add an event source for a file descriptor.
467 * @param pollfd The GPollFD.
468 * @param timeout Max time to wait before the callback is called, ignored if 0.
469 * @param cb Callback function to add. Must not be NULL.
470 * @param cb_data Data for the callback function. Can be NULL.
471 * @param poll_object TODO.
473 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
474 * SR_ERR_MALLOC upon memory allocation errors.
476 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
477 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
479 struct source *new_sources, *s;
480 GPollFD *new_pollfds;
483 sr_err("session: %s: cb was NULL", __func__);
487 /* Note: cb_data can be NULL, that's not a bug. */
489 new_pollfds = g_try_realloc(session->pollfds,
490 sizeof(GPollFD) * (session->num_sources + 1));
492 sr_err("session: %s: new_pollfds malloc failed", __func__);
493 return SR_ERR_MALLOC;
496 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
497 (session->num_sources + 1));
499 sr_err("session: %s: new_sources malloc failed", __func__);
500 return SR_ERR_MALLOC;
503 new_pollfds[session->num_sources] = *pollfd;
504 s = &new_sources[session->num_sources++];
505 s->timeout = timeout;
507 s->cb_data = cb_data;
508 s->poll_object = poll_object;
509 session->pollfds = new_pollfds;
510 session->sources = new_sources;
512 if (timeout != session->source_timeout && timeout > 0
513 && (session->source_timeout == -1 || timeout < session->source_timeout))
514 session->source_timeout = timeout;
520 * Add an event source for a file descriptor.
522 * @param fd The file descriptor.
523 * @param events Events to check for.
524 * @param timeout Max time to wait before the callback is called, ignored if 0.
525 * @param cb Callback function to add. Must not be NULL.
526 * @param cb_data Data for the callback function. Can be NULL.
528 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
529 * SR_ERR_MALLOC upon memory allocation errors.
531 SR_API int sr_session_source_add(int fd, int events, int timeout,
532 sr_receive_data_callback_t cb, void *cb_data)
539 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
543 * Add an event source for a GPollFD.
545 * @param pollfd The GPollFD.
546 * @param timeout Max time to wait before the callback is called, ignored if 0.
547 * @param cb Callback function to add. Must not be NULL.
548 * @param cb_data Data for the callback function. Can be NULL.
550 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
551 * SR_ERR_MALLOC upon memory allocation errors.
553 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
554 sr_receive_data_callback_t cb, void *cb_data)
556 return _sr_session_source_add(pollfd, timeout, cb,
557 cb_data, (gintptr)pollfd);
561 * Add an event source for a GIOChannel.
563 * @param channel The GIOChannel.
564 * @param events Events to poll on.
565 * @param timeout Max time to wait before the callback is called, ignored if 0.
566 * @param cb Callback function to add. Must not be NULL.
567 * @param cb_data Data for the callback function. Can be NULL.
569 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
570 * SR_ERR_MALLOC upon memory allocation errors.
572 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
573 int timeout, sr_receive_data_callback_t cb, void *cb_data)
578 g_io_channel_win32_make_pollfd(channel, events, &p);
580 p.fd = g_io_channel_unix_get_fd(channel);
584 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
588 * Remove the source belonging to the specified channel.
590 * @todo Add more error checks and logging.
592 * @param channel The channel for which the source should be removed.
594 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
595 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
598 static int _sr_session_source_remove(gintptr poll_object)
600 struct source *new_sources;
601 GPollFD *new_pollfds;
604 if (!session->sources || !session->num_sources) {
605 sr_err("session: %s: sources was NULL", __func__);
609 for (old = 0; old < session->num_sources; old++) {
610 if (session->sources[old].poll_object == poll_object)
614 /* fd not found, nothing to do */
615 if (old == session->num_sources)
618 session->num_sources -= 1;
620 if (old != session->num_sources) {
621 memmove(&session->pollfds[old], &session->pollfds[old+1],
622 (session->num_sources - old) * sizeof(GPollFD));
623 memmove(&session->sources[old], &session->sources[old+1],
624 (session->num_sources - old) * sizeof(struct source));
627 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
628 if (!new_pollfds && session->num_sources > 0) {
629 sr_err("session: %s: new_pollfds malloc failed", __func__);
630 return SR_ERR_MALLOC;
633 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
634 if (!new_sources && session->num_sources > 0) {
635 sr_err("session: %s: new_sources malloc failed", __func__);
636 return SR_ERR_MALLOC;
639 session->pollfds = new_pollfds;
640 session->sources = new_sources;
646 * Remove the source belonging to the specified file descriptor.
648 * @param fd The file descriptor for which the source should be removed.
650 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
651 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
654 SR_API int sr_session_source_remove(int fd)
656 return _sr_session_source_remove((gintptr)fd);
660 * Remove the source belonging to the specified poll descriptor.
662 * @param pollfd The poll descriptor for which the source should be removed.
664 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
665 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
668 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
670 return _sr_session_source_remove((gintptr)pollfd);
674 * Remove the source belonging to the specified channel.
676 * @param channel The channel for which the source should be removed.
678 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
679 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
682 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
684 return _sr_session_source_remove((gintptr)channel);