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 * @return SR_OK upon success, SR_ERR on errors.
244 SR_API int sr_session_iteration(gboolean block)
249 ret = g_poll(session->pollfds, session->num_sources,
250 block ? session->source_timeout : 0);
251 for (i = 0; i < session->num_sources; i++) {
252 if (session->pollfds[i].revents > 0 || (ret == 0
253 && session->source_timeout == session->sources[i].timeout)) {
255 * Invoke the source's callback on an event,
256 * or if the poll timed out and this source
257 * asked for that timeout.
259 if (!session->sources[i].cb(session->pollfds[i].fd,
260 session->pollfds[i].revents,
261 session->sources[i].cb_data))
262 sr_session_source_remove(session->sources[i].poll_object);
265 * We want to take as little time as possible to stop
266 * the session if we have been told to do so. Therefore,
267 * we check the flag after processing every source, not
268 * just once per main event loop.
270 g_mutex_lock(&session->stop_mutex);
271 if (session->abort_session) {
272 sr_session_stop_sync();
273 /* But once is enough. */
274 session->abort_session = FALSE;
276 g_mutex_unlock(&session->stop_mutex);
285 * There can only be one session at a time.
287 * @return SR_OK upon success, SR_ERR upon errors.
289 SR_API int sr_session_start(void)
291 struct sr_dev_inst *sdi;
296 sr_err("%s: session was NULL; a session must be "
297 "created before starting it.", __func__);
301 if (!session->devs) {
302 sr_err("%s: session->devs was NULL; a session "
303 "cannot be started without devices.", __func__);
307 sr_info("Starting.");
310 for (l = session->devs; l; l = l->next) {
312 if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
313 sr_err("%s: could not start an acquisition "
314 "(%d)", __func__, ret);
319 /* TODO: What if there are multiple devices? Which return code? */
327 * @return SR_OK upon success, SR_ERR_BUG upon errors.
329 SR_API int sr_session_run(void)
332 sr_err("%s: session was NULL; a session must be "
333 "created first, before running it.", __func__);
337 if (!session->devs) {
338 /* TODO: Actually the case? */
339 sr_err("%s: session->devs was NULL; a session "
340 "cannot be run without devices.", __func__);
346 /* Do we have real sources? */
347 if (session->num_sources == 1 && session->pollfds[0].fd == -1) {
348 /* Dummy source, freewheel over it. */
349 while (session->num_sources)
350 session->sources[0].cb(-1, 0, session->sources[0].cb_data);
352 /* Real sources, use g_poll() main loop. */
353 while (session->num_sources)
354 sr_session_iteration(TRUE);
361 * Stop the current session.
363 * The current session is stopped immediately, with all acquisition sessions
364 * being stopped and hardware drivers cleaned up.
366 * This must be called from within the session thread, to prevent freeing
367 * resources that the session thread will try to use.
369 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
371 SR_PRIV int sr_session_stop_sync(void)
373 struct sr_dev_inst *sdi;
377 sr_err("%s: session was NULL", __func__);
381 sr_info("Stopping.");
383 for (l = session->devs; l; l = l->next) {
386 if (sdi->driver->dev_acquisition_stop)
387 sdi->driver->dev_acquisition_stop(sdi, sdi);
395 * Stop the current session.
397 * The current session is stopped immediately, with all acquisition sessions
398 * being stopped and hardware drivers cleaned up.
400 * If the session is run in a separate thread, this function will not block
401 * until the session is finished executing. It is the caller's responsibility
402 * to wait for the session thread to return before assuming that the session is
403 * completely decommissioned.
405 * @return SR_OK upon success, SR_ERR_BUG if no session exists.
407 SR_API int sr_session_stop(void)
410 sr_err("%s: session was NULL", __func__);
414 g_mutex_lock(&session->stop_mutex);
415 session->abort_session = TRUE;
416 g_mutex_unlock(&session->stop_mutex);
424 * @param packet The packet to show debugging information for.
426 static void datafeed_dump(const struct sr_datafeed_packet *packet)
428 const struct sr_datafeed_logic *logic;
429 const struct sr_datafeed_analog *analog;
431 switch (packet->type) {
433 sr_dbg("bus: Received SR_DF_HEADER packet.");
436 sr_dbg("bus: Received SR_DF_TRIGGER packet.");
439 sr_dbg("bus: Received SR_DF_META packet.");
442 logic = packet->payload;
443 sr_dbg("bus: Received SR_DF_LOGIC packet (%" PRIu64 " bytes).",
447 analog = packet->payload;
448 sr_dbg("bus: Received SR_DF_ANALOG packet (%d samples).",
449 analog->num_samples);
452 sr_dbg("bus: Received SR_DF_END packet.");
454 case SR_DF_FRAME_BEGIN:
455 sr_dbg("bus: Received SR_DF_FRAME_BEGIN packet.");
457 case SR_DF_FRAME_END:
458 sr_dbg("bus: Received SR_DF_FRAME_END packet.");
461 sr_dbg("bus: Received unknown packet type: %d.", packet->type);
467 * Send a packet to whatever is listening on the datafeed bus.
469 * Hardware drivers use this to send a data packet to the frontend.
472 * @param packet The datafeed packet to send to the session bus.
474 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
478 SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
479 const struct sr_datafeed_packet *packet)
482 struct datafeed_callback *cb_struct;
485 sr_err("%s: sdi was NULL", __func__);
490 sr_err("%s: packet was NULL", __func__);
494 for (l = session->datafeed_callbacks; l; l = l->next) {
495 if (sr_log_loglevel_get() >= SR_LOG_DBG)
496 datafeed_dump(packet);
498 cb_struct->cb(sdi, packet, cb_struct->cb_data);
505 * Add an event source for a file descriptor.
507 * @param pollfd The GPollFD.
508 * @param timeout Max time to wait before the callback is called, ignored if 0.
509 * @param cb Callback function to add. Must not be NULL.
510 * @param cb_data Data for the callback function. Can be NULL.
511 * @param poll_object TODO.
513 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
514 * SR_ERR_MALLOC upon memory allocation errors.
516 static int _sr_session_source_add(GPollFD *pollfd, int timeout,
517 sr_receive_data_callback_t cb, void *cb_data, gintptr poll_object)
519 struct source *new_sources, *s;
520 GPollFD *new_pollfds;
523 sr_err("%s: cb was NULL", __func__);
527 /* Note: cb_data can be NULL, that's not a bug. */
529 new_pollfds = g_try_realloc(session->pollfds,
530 sizeof(GPollFD) * (session->num_sources + 1));
532 sr_err("%s: new_pollfds malloc failed", __func__);
533 return SR_ERR_MALLOC;
536 new_sources = g_try_realloc(session->sources, sizeof(struct source) *
537 (session->num_sources + 1));
539 sr_err("%s: new_sources malloc failed", __func__);
540 return SR_ERR_MALLOC;
543 new_pollfds[session->num_sources] = *pollfd;
544 s = &new_sources[session->num_sources++];
545 s->timeout = timeout;
547 s->cb_data = cb_data;
548 s->poll_object = poll_object;
549 session->pollfds = new_pollfds;
550 session->sources = new_sources;
552 if (timeout != session->source_timeout && timeout > 0
553 && (session->source_timeout == -1 || timeout < session->source_timeout))
554 session->source_timeout = timeout;
560 * Add an event source for a file descriptor.
562 * @param fd The file descriptor.
563 * @param events Events to check for.
564 * @param timeout Max time to wait before the callback is called, ignored if 0.
565 * @param cb Callback function to add. Must not be NULL.
566 * @param cb_data Data for the callback function. Can be NULL.
568 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
569 * SR_ERR_MALLOC upon memory allocation errors.
571 SR_API int sr_session_source_add(int fd, int events, int timeout,
572 sr_receive_data_callback_t cb, void *cb_data)
579 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)fd);
583 * Add an event source for a GPollFD.
585 * @param pollfd The GPollFD.
586 * @param timeout Max time to wait before the callback is called, ignored if 0.
587 * @param cb Callback function to add. Must not be NULL.
588 * @param cb_data Data for the callback function. Can be NULL.
590 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
591 * SR_ERR_MALLOC upon memory allocation errors.
593 SR_API int sr_session_source_add_pollfd(GPollFD *pollfd, int timeout,
594 sr_receive_data_callback_t cb, void *cb_data)
596 return _sr_session_source_add(pollfd, timeout, cb,
597 cb_data, (gintptr)pollfd);
601 * Add an event source for a GIOChannel.
603 * @param channel The GIOChannel.
604 * @param events Events to poll on.
605 * @param timeout Max time to wait before the callback is called, ignored if 0.
606 * @param cb Callback function to add. Must not be NULL.
607 * @param cb_data Data for the callback function. Can be NULL.
609 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
610 * SR_ERR_MALLOC upon memory allocation errors.
612 SR_API int sr_session_source_add_channel(GIOChannel *channel, int events,
613 int timeout, sr_receive_data_callback_t cb, void *cb_data)
618 g_io_channel_win32_make_pollfd(channel, events, &p);
620 p.fd = g_io_channel_unix_get_fd(channel);
624 return _sr_session_source_add(&p, timeout, cb, cb_data, (gintptr)channel);
628 * Remove the source belonging to the specified channel.
630 * @todo Add more error checks and logging.
632 * @param channel The channel for which the source should be removed.
634 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
635 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
638 static int _sr_session_source_remove(gintptr poll_object)
640 struct source *new_sources;
641 GPollFD *new_pollfds;
644 if (!session->sources || !session->num_sources) {
645 sr_err("%s: sources was NULL", __func__);
649 for (old = 0; old < session->num_sources; old++) {
650 if (session->sources[old].poll_object == poll_object)
654 /* fd not found, nothing to do */
655 if (old == session->num_sources)
658 session->num_sources -= 1;
660 if (old != session->num_sources) {
661 memmove(&session->pollfds[old], &session->pollfds[old+1],
662 (session->num_sources - old) * sizeof(GPollFD));
663 memmove(&session->sources[old], &session->sources[old+1],
664 (session->num_sources - old) * sizeof(struct source));
667 new_pollfds = g_try_realloc(session->pollfds, sizeof(GPollFD) * session->num_sources);
668 if (!new_pollfds && session->num_sources > 0) {
669 sr_err("%s: new_pollfds malloc failed", __func__);
670 return SR_ERR_MALLOC;
673 new_sources = g_try_realloc(session->sources, sizeof(struct source) * session->num_sources);
674 if (!new_sources && session->num_sources > 0) {
675 sr_err("%s: new_sources malloc failed", __func__);
676 return SR_ERR_MALLOC;
679 session->pollfds = new_pollfds;
680 session->sources = new_sources;
686 * Remove the source belonging to the specified file descriptor.
688 * @param fd The file descriptor for which the source should be removed.
690 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
691 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
694 SR_API int sr_session_source_remove(int fd)
696 return _sr_session_source_remove((gintptr)fd);
700 * Remove the source belonging to the specified poll descriptor.
702 * @param pollfd The poll descriptor for which the source should be removed.
704 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
705 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
708 SR_API int sr_session_source_remove_pollfd(GPollFD *pollfd)
710 return _sr_session_source_remove((gintptr)pollfd);
714 * Remove the source belonging to the specified channel.
716 * @param channel The channel for which the source should be removed.
718 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
719 * SR_ERR_MALLOC upon memory allocation errors, SR_ERR_BUG upon
722 SR_API int sr_session_source_remove_channel(GIOChannel *channel)
724 return _sr_session_source_remove((gintptr)channel);