* This file is part of the libsigrok project.
*
* Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
+ * Copyright (C) 2015 Daniel Elstner <daniel.kitta@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* @{
*/
-struct source {
- int64_t timeout; /* microseconds */
- int64_t due; /* microseconds */
-
- sr_receive_data_callback cb;
+struct datafeed_callback {
+ sr_datafeed_callback cb;
void *cb_data;
+};
- /* This is used to keep track of the object (fd, pollfd or channel) which is
- * being polled and will be used to match the source when removing it again.
- */
- gintptr poll_object;
+/** Custom GLib event source for generic descriptor I/O.
+ * @internal
+ */
+struct fd_source {
+ GSource base;
- /* Number of fds to poll for this source. This will be 0 for timer
- * sources, 1 for normal I/O sources, and 1 or more for libusb I/O
- * sources on Unix platforms.
- */
- int num_fds;
+ int64_t timeout_us;
+ int64_t due_us;
- gboolean triggered;
-};
+ /* Meta-data needed to keep track of installed sources */
+ struct sr_session *session;
+ void *key;
-struct datafeed_callback {
- sr_datafeed_callback cb;
- void *cb_data;
+ GPollFD pollfd;
};
+/** FD event source prepare() method.
+ */
+static gboolean fd_source_prepare(GSource *source, int *timeout)
+{
+ int64_t now_us;
+ struct fd_source *fsource;
+ int remaining_ms;
+
+ fsource = (struct fd_source *)source;
+
+ if (fsource->timeout_us >= 0) {
+ now_us = g_source_get_time(source);
+
+ if (fsource->due_us == 0) {
+ /* First-time initialization of the expiration time */
+ fsource->due_us = now_us + fsource->timeout_us;
+ }
+ remaining_ms = (MAX(0, fsource->due_us - now_us) + 999) / 1000;
+ } else {
+ remaining_ms = -1;
+ }
+ *timeout = remaining_ms;
+
+ return (remaining_ms == 0);
+}
+
+/** FD event source check() method.
+ */
+static gboolean fd_source_check(GSource *source)
+{
+ struct fd_source *fsource;
+ unsigned int revents;
+
+ fsource = (struct fd_source *)source;
+ revents = fsource->pollfd.revents;
+
+ return (revents != 0 || (fsource->timeout_us >= 0
+ && fsource->due_us <= g_source_get_time(source)));
+}
+
+/** FD event source dispatch() method.
+ */
+static gboolean fd_source_dispatch(GSource *source,
+ GSourceFunc callback, void *user_data)
+{
+ struct fd_source *fsource;
+ const char *name;
+ unsigned int revents;
+ gboolean keep;
+
+ fsource = (struct fd_source *)source;
+ name = g_source_get_name(source);
+ revents = fsource->pollfd.revents;
+
+ if (revents != 0) {
+ sr_spew("%s: %s " G_POLLFD_FORMAT ", revents 0x%.2X",
+ __func__, name, fsource->pollfd.fd, revents);
+ } else {
+ sr_spew("%s: %s " G_POLLFD_FORMAT ", timed out",
+ __func__, name, fsource->pollfd.fd);
+ }
+ if (!callback) {
+ sr_err("Callback not set, cannot dispatch event.");
+ return G_SOURCE_REMOVE;
+ }
+ keep = (*(sr_receive_data_callback)callback)
+ (fsource->pollfd.fd, revents, user_data);
+
+ if (fsource->timeout_us >= 0 && G_LIKELY(keep)
+ && G_LIKELY(!g_source_is_destroyed(source)))
+ fsource->due_us = g_source_get_time(source)
+ + fsource->timeout_us;
+ return keep;
+}
+
+/** FD event source finalize() method.
+ */
+static void fd_source_finalize(GSource *source)
+{
+ struct fd_source *fsource;
+
+ fsource = (struct fd_source *)source;
+
+ sr_dbg("%s: key %p", __func__, fsource->key);
+
+ sr_session_source_destroyed(fsource->session, fsource->key, source);
+}
+
+/** Create an event source for I/O on a file descriptor.
+ *
+ * In order to maintain API compatibility, this event source also doubles
+ * as a timer event source.
+ *
+ * @param session The session the event source belongs to.
+ * @param key The key used to identify this source.
+ * @param fd The file descriptor or HANDLE.
+ * @param timeout_ms The timeout interval in ms, or -1 to wait indefinitely.
+ * @return A new event source object, or NULL on failure.
+ */
+static GSource *fd_source_new(struct sr_session *session, void *key,
+ gintptr fd, int events, int timeout_ms)
+{
+ static GSourceFuncs fd_source_funcs = {
+ .prepare = &fd_source_prepare,
+ .check = &fd_source_check,
+ .dispatch = &fd_source_dispatch,
+ .finalize = &fd_source_finalize
+ };
+ GSource *source;
+ struct fd_source *fsource;
+
+ source = g_source_new(&fd_source_funcs, sizeof(struct fd_source));
+ fsource = (struct fd_source *)source;
+
+ g_source_set_name(source, (fd < 0) ? "timer" : "fd");
+
+ if (timeout_ms >= 0) {
+ fsource->timeout_us = 1000 * (int64_t)timeout_ms;
+ fsource->due_us = 0;
+ } else {
+ fsource->timeout_us = -1;
+ fsource->due_us = INT64_MAX;
+ }
+ fsource->session = session;
+ fsource->key = key;
+
+ fsource->pollfd.fd = fd;
+ fsource->pollfd.events = events;
+ fsource->pollfd.revents = 0;
+
+ if (fd >= 0)
+ g_source_add_poll(source, &fsource->pollfd);
+
+ return source;
+}
+
/**
* Create a new session.
*
session->ctx = ctx;
- session->sources = g_array_new(FALSE, FALSE, sizeof(struct source));
- session->pollfds = g_array_new(FALSE, FALSE, sizeof(GPollFD));
+ g_mutex_init(&session->main_mutex);
- g_mutex_init(&session->stop_mutex);
+ /* To maintain API compatibility, we need a lookup table
+ * which maps poll_object IDs to GSource* pointers.
+ */
+ session->event_sources = g_hash_table_new(NULL, NULL);
*new_session = session;
}
sr_session_dev_remove_all(session);
- g_mutex_clear(&session->stop_mutex);
-
g_slist_free_full(session->owned_devs, (GDestroyNotify)sr_dev_inst_free);
- g_array_unref(session->pollfds);
- g_array_unref(session->sources);
+ g_hash_table_unref(session->event_sources);
+
+ g_mutex_clear(&session->main_mutex);
g_free(session);
return SR_OK;
}
-static gboolean sr_session_check_aborted(struct sr_session *session)
-{
- gboolean stop;
-
- g_mutex_lock(&session->stop_mutex);
- stop = session->abort_session;
- if (stop) {
- sr_session_stop_sync(session);
- /* But once is enough. */
- session->abort_session = FALSE;
- }
- g_mutex_unlock(&session->stop_mutex);
-
- return stop;
-}
-
-/**
- * Poll the session's event sources.
- *
- * @param session The session to use. Must not be NULL.
- * @retval SR_OK Success.
- * @retval SR_ERR Error occurred.
- */
-static int sr_session_iteration(struct sr_session *session)
-{
- int64_t start_time, stop_time, min_due, due;
- int timeout_ms;
- unsigned int i;
- int k, fd_index;
- int ret;
- int fd;
- int revents;
- gboolean triggered, stopped;
- struct source *source;
- GPollFD *pollfd;
- gintptr poll_object;
-#if HAVE_LIBUSB_1_0
- int64_t usb_timeout;
- int64_t usb_due;
- struct timeval tv;
-#endif
- if (session->sources->len == 0) {
- sr_session_check_aborted(session);
- return SR_OK;
- }
- start_time = g_get_monotonic_time();
- min_due = INT64_MAX;
-
- for (i = 0; i < session->sources->len; ++i) {
- source = &g_array_index(session->sources, struct source, i);
- if (source->due < min_due)
- min_due = source->due;
- source->triggered = FALSE;
- }
-#if HAVE_LIBUSB_1_0
- usb_due = INT64_MAX;
- if (session->ctx->usb_source_present) {
- ret = libusb_get_next_timeout(session->ctx->libusb_ctx, &tv);
- if (ret < 0) {
- sr_err("Error getting libusb timeout: %s",
- libusb_error_name(ret));
- return SR_ERR;
- } else if (ret == 1) {
- usb_timeout = (int64_t)tv.tv_sec * G_USEC_PER_SEC
- + tv.tv_usec;
- usb_due = start_time + usb_timeout;
- if (usb_due < min_due)
- min_due = usb_due;
-
- sr_spew("poll: next USB timeout %g ms",
- 1e-3 * usb_timeout);
- }
- }
-#endif
- if (min_due == INT64_MAX)
- timeout_ms = -1;
- else if (min_due > start_time)
- timeout_ms = MIN((min_due - start_time + 999) / 1000, INT_MAX);
- else
- timeout_ms = 0;
-
- sr_spew("poll enter: %u sources, %u fds, %d ms timeout",
- session->sources->len, session->pollfds->len, timeout_ms);
-
- ret = g_poll((GPollFD *)session->pollfds->data,
- session->pollfds->len, timeout_ms);
-#ifdef G_OS_UNIX
- if (ret < 0 && errno != EINTR) {
- sr_err("Error in poll: %s", g_strerror(errno));
- return SR_ERR;
- }
-#else
- if (ret < 0) {
- sr_err("Error in poll: %d", ret);
- return SR_ERR;
- }
-#endif
- stop_time = g_get_monotonic_time();
-
- sr_spew("poll leave: %g ms elapsed, %d events",
- 1e-3 * (stop_time - start_time), ret);
-
- triggered = FALSE;
- stopped = FALSE;
- fd_index = 0;
-
- for (i = 0; i < session->sources->len; ++i) {
- source = &g_array_index(session->sources, struct source, i);
-
- poll_object = source->poll_object;
- fd = (int)poll_object;
- revents = 0;
-
- for (k = 0; k < source->num_fds; ++k) {
- pollfd = &g_array_index(session->pollfds,
- GPollFD, fd_index + k);
- fd = pollfd->fd;
- revents |= pollfd->revents;
- }
- fd_index += source->num_fds;
-
- if (source->triggered)
- continue; /* already handled */
- if (ret > 0 && revents == 0)
- continue; /* skip timeouts if any I/O event occurred */
-
- /* Make invalid to avoid confusion in case of multiple FDs. */
- if (source->num_fds > 1)
- fd = -1;
- if (ret <= 0)
- revents = 0;
-
- due = source->due;
-#if HAVE_LIBUSB_1_0
- if (usb_due < due && poll_object
- == (gintptr)session->ctx->libusb_ctx)
- due = usb_due;
-#endif
- if (revents == 0 && stop_time < due)
- continue;
- /*
- * The source may be gone after the callback returns,
- * so access any data now that needs accessing.
- */
- if (source->timeout >= 0)
- source->due = stop_time + source->timeout;
- source->triggered = TRUE;
- triggered = TRUE;
- /*
- * Invoke the source's callback on an event or timeout.
- */
- sr_spew("callback for event source %" G_GINTPTR_FORMAT " with"
- " event mask 0x%.2X", poll_object, (unsigned)revents);
- if (!source->cb(fd, revents, source->cb_data)) {
-#if HAVE_LIBUSB_1_0
- /* Hackish, to be cleaned up when porting to
- * the GLib main loop.
- */
- if (poll_object == (gintptr)session->ctx->libusb_ctx)
- usb_source_remove(session, session->ctx);
- else
-#endif
- sr_session_source_remove_internal(session,
- poll_object);
- }
- /*
- * We want to take as little time as possible to stop
- * the session if we have been told to do so. Therefore,
- * we check the flag after processing every source, not
- * just once per main event loop.
- */
- if (!stopped)
- stopped = sr_session_check_aborted(session);
-
- /* Restart loop as the sources list may have changed. */
- fd_index = 0;
- i = 0;
- }
-
- /* Check for abort at least once per iteration. */
- if (!triggered)
- sr_session_check_aborted(session);
-
- return SR_OK;
-}
-
static int verify_trigger(struct sr_trigger *trigger)
{
struct sr_trigger_stage *stage;
return SR_OK;
}
+/** Set up the main context the session will be executing in.
+ *
+ * Must be called just before the session starts, by the thread which
+ * will execute the session main loop. Once acquired, the main context
+ * pointer is immutable for the duration of the session run.
+ */
+static int set_main_context(struct sr_session *session)
+{
+ GMainContext *def_context;
+
+ /* May happen if sr_session_start() is called again after
+ * sr_session_run(), but the session hasn't been stopped yet.
+ */
+ if (session->main_loop) {
+ sr_err("Cannot set main context; main loop already created.");
+ return SR_ERR;
+ }
+
+ g_mutex_lock(&session->main_mutex);
+
+ def_context = g_main_context_get_thread_default();
+
+ if (!def_context)
+ def_context = g_main_context_default();
+ /*
+ * Try to use an existing main context if possible, but only if we
+ * can make it owned by the current thread. Otherwise, create our
+ * own main context so that event source callbacks can execute in
+ * the session thread.
+ */
+ if (g_main_context_acquire(def_context)) {
+ g_main_context_release(def_context);
+
+ sr_dbg("Using thread-default main context.");
+
+ session->main_context = def_context;
+ session->main_context_is_default = TRUE;
+ } else {
+ sr_dbg("Creating our own main context.");
+
+ session->main_context = g_main_context_new();
+ session->main_context_is_default = FALSE;
+ }
+ g_mutex_unlock(&session->main_mutex);
+
+ return SR_OK;
+}
+
+/** Unset the main context used for the current session run.
+ *
+ * Must be called right after stopping the session. Note that if the
+ * session is stopped asynchronously, the main loop may still be running
+ * after the main context has been unset. This is OK as long as no new
+ * event sources are created -- the main loop holds its own reference
+ * to the main context.
+ */
+static int unset_main_context(struct sr_session *session)
+{
+ int ret;
+
+ g_mutex_lock(&session->main_mutex);
+
+ if (session->main_context) {
+ if (!session->main_context_is_default)
+ g_main_context_unref(session->main_context);
+
+ session->main_context = NULL;
+ ret = SR_OK;
+ } else {
+ /* May happen if the set/unset calls are not matched.
+ */
+ sr_err("No main context to unset.");
+ ret = SR_ERR;
+ }
+ g_mutex_unlock(&session->main_mutex);
+
+ return ret;
+}
+
/**
* Start a session.
*
if (session->trigger && verify_trigger(session->trigger) != SR_OK)
return SR_ERR;
+ ret = set_main_context(session);
+ if (ret != SR_OK)
+ return ret;
+
+ session->running = TRUE;
+
sr_info("Starting.");
- ret = SR_OK;
for (l = session->devs; l; l = l->next) {
sdi = l->data;
enabled_channels = 0;
}
}
+ if (ret != SR_OK) {
+ unset_main_context(session);
+ session->running = FALSE;
+ }
/* TODO: What if there are multiple devices? Which return code? */
return ret;
*/
SR_API int sr_session_run(struct sr_session *session)
{
- int ret;
-
if (!session) {
sr_err("%s: session was NULL", __func__);
return SR_ERR_ARG;
}
-
if (!session->devs) {
/* TODO: Actually the case? */
sr_err("%s: session->devs was NULL; a session "
"cannot be run without devices.", __func__);
return SR_ERR_ARG;
}
- session->running = TRUE;
+ if (session->main_loop) {
+ sr_err("Main loop already created.");
+ return SR_ERR;
+ }
+ if (g_hash_table_size(session->event_sources) == 0) {
+ sr_err("Refusing to run without any event sources.");
+ return SR_ERR;
+ }
+ g_mutex_lock(&session->main_mutex);
+ if (!session->main_context) {
+ sr_err("Cannot run without main context.");
+ g_mutex_unlock(&session->main_mutex);
+ return SR_ERR;
+ }
sr_info("Running.");
- /* Poll event sources until none are left. */
- while (session->sources->len > 0) {
- ret = sr_session_iteration(session);
- if (ret != SR_OK)
- return ret;
- }
+ session->main_loop = g_main_loop_new(session->main_context, FALSE);
+ g_mutex_unlock(&session->main_mutex);
+
+ g_main_loop_run(session->main_loop);
+
+ g_main_loop_unref(session->main_loop);
+ session->main_loop = NULL;
+
return SR_OK;
}
-/**
- * Stop a session.
- *
- * The session is stopped immediately, with all acquisition sessions stopped
- * and hardware drivers cleaned up.
- *
- * This must be called from within the session thread, to prevent freeing
- * resources that the session thread will try to use.
- *
- * @param session The session to use. Must not be NULL.
- *
- * @retval SR_OK Success.
- * @retval SR_ERR_ARG Invalid session passed.
- *
- * @private
- */
-SR_PRIV int sr_session_stop_sync(struct sr_session *session)
+static gboolean session_stop_sync(void *user_data)
{
+ struct sr_session *session;
struct sr_dev_inst *sdi;
- GSList *l;
+ GSList *node;
- if (!session) {
- sr_err("%s: session was NULL", __func__);
- return SR_ERR_ARG;
- }
+ session = user_data;
+
+ if (!session->running)
+ return G_SOURCE_REMOVE;
sr_info("Stopping.");
- for (l = session->devs; l; l = l->next) {
- sdi = l->data;
- if (sdi->driver) {
- if (sdi->driver->dev_acquisition_stop)
- sdi->driver->dev_acquisition_stop(sdi, sdi);
- }
+ for (node = session->devs; node; node = node->next) {
+ sdi = node->data;
+ if (sdi->driver && sdi->driver->dev_acquisition_stop)
+ sdi->driver->dev_acquisition_stop(sdi, sdi);
}
session->running = FALSE;
- return SR_OK;
+ return G_SOURCE_REMOVE;
}
/**
*
* @retval SR_OK Success.
* @retval SR_ERR_ARG Invalid session passed.
+ * @retval SR_ERR Other error.
*
* @since 0.4.0
*/
{
if (!session) {
sr_err("%s: session was NULL", __func__);
- return SR_ERR_BUG;
+ return SR_ERR_ARG;
}
+ g_mutex_lock(&session->main_mutex);
- g_mutex_lock(&session->stop_mutex);
- session->abort_session = TRUE;
- g_mutex_unlock(&session->stop_mutex);
+ if (session->main_context) {
+ g_main_context_invoke(session->main_context,
+ &session_stop_sync, session);
+ } else {
+ sr_err("No main context set; already stopped?");
+ }
+ g_mutex_unlock(&session->main_mutex);
- return SR_OK;
+ return unset_main_context(session);
}
/**
* Add an event source for a file descriptor.
*
* @param session The session to use. Must not be NULL.
- * @param[in] timeout Max time in ms to wait before the callback is called,
- * or -1 to wait indefinitely.
- * @param cb Callback function to add. Must not be NULL.
- * @param cb_data Data for the callback function. Can be NULL.
- * @param poll_object Handle by which the source is identified
- *
+ * @param key The key which identifies the event source.
+ * @param source An event source object. Must not be NULL.
* @retval SR_OK Success.
* @retval SR_ERR_ARG Invalid argument.
- * @retval SR_ERR An event source for @a poll_object is already installed.
+ * @retval SR_ERR_BUG Event source with @a key already installed.
+ * @retval SR_ERR Other error.
*/
SR_PRIV int sr_session_source_add_internal(struct sr_session *session,
- int timeout, sr_receive_data_callback cb, void *cb_data,
- gintptr poll_object)
+ void *key, GSource *source)
{
- struct source src;
- unsigned int i;
-
- /* Note: cb_data can be NULL, that's not a bug. */
- if (!cb) {
- sr_err("%s: cb was NULL", __func__);
- return SR_ERR_ARG;
- }
- /* Make sure that poll_object is unique.
+ int ret;
+ /*
+ * This must not ever happen, since the source has already been
+ * created and its finalize() method will remove the key for the
+ * already installed source. (Well it would, if we did not have
+ * another sanity check there.)
*/
- for (i = 0; i < session->sources->len; ++i) {
- if (g_array_index(session->sources, struct source, i)
- .poll_object == poll_object) {
- sr_err("Event source %" G_GINTPTR_FORMAT
- " already installed.", poll_object);
- return SR_ERR;
- }
+ if (g_hash_table_contains(session->event_sources, key)) {
+ sr_err("Event source with key %p already exists.", key);
+ return SR_ERR_BUG;
}
- sr_dbg("Installing event source %" G_GINTPTR_FORMAT
- " with %d ms timeout.", poll_object, timeout);
- src.cb = cb;
- src.cb_data = cb_data;
- src.poll_object = poll_object;
- src.num_fds = 0;
- src.triggered = FALSE;
-
- if (timeout >= 0) {
- src.timeout = INT64_C(1000) * timeout;
- src.due = g_get_monotonic_time() + src.timeout;
+ g_hash_table_insert(session->event_sources, key, source);
+
+ g_mutex_lock(&session->main_mutex);
+
+ if (session->main_context) {
+ if (g_source_attach(source, session->main_context) > 0)
+ ret = SR_OK;
+ else
+ ret = SR_ERR;
} else {
- src.timeout = -1;
- src.due = INT64_MAX;
+ sr_err("Cannot add event source without main context.");
+ ret = SR_ERR;
}
- g_array_append_val(session->sources, src);
+ g_mutex_unlock(&session->main_mutex);
- return SR_OK;
+ return ret;
}
-SR_PRIV int sr_session_source_poll_add(struct sr_session *session,
- gintptr poll_object, gintptr fd, int events)
+static int attach_fd_source(struct sr_session *session,
+ void *key, int fd, int events, int timeout,
+ sr_receive_data_callback cb, void *cb_data)
{
- struct source *source;
- GPollFD pollfd;
- unsigned int i;
- int fd_index, k;
-
- source = NULL;
- fd_index = 0;
+ GSource *source;
+ int ret;
- /* Look up existing event source.
- */
- for (i = 0; i < session->sources->len; ++i) {
- source = &g_array_index(session->sources, struct source, i);
- if (source->poll_object == poll_object)
- break;
- fd_index += source->num_fds;
- }
- if (!source) {
- sr_err("Cannot add poll FD %" G_GINTPTR_FORMAT
- " to non-existing event source %" G_GINTPTR_FORMAT
- ".", fd, poll_object);
+ source = fd_source_new(session, key, fd, events, timeout);
+ if (!source)
return SR_ERR;
- }
- /* Make sure the FD is unique.
- */
- for (k = 0; k < source->num_fds; ++k)
- if (g_array_index(session->pollfds, GPollFD, fd_index + k)
- .fd == fd) {
- sr_err("Cannot add poll FD %" G_GINTPTR_FORMAT
- " twice to event source %" G_GINTPTR_FORMAT
- ".", fd, poll_object);
- return SR_ERR;
- }
-
- pollfd.fd = fd;
- pollfd.events = events;
- pollfd.revents = 0;
- g_array_insert_val(session->pollfds,
- fd_index + source->num_fds, pollfd);
- ++source->num_fds;
+ g_source_set_callback(source, (GSourceFunc)cb, cb_data, NULL);
- sr_dbg("Added poll FD %" G_GINTPTR_FORMAT " with event mask 0x%.2X"
- " to event source %" G_GINTPTR_FORMAT ".",
- fd, (unsigned)events, poll_object);
+ ret = sr_session_source_add_internal(session, key, source);
+ g_source_unref(source);
- return SR_OK;
+ return ret;
}
/**
SR_API int sr_session_source_add(struct sr_session *session, int fd,
int events, int timeout, sr_receive_data_callback cb, void *cb_data)
{
- int ret;
-
if (fd < 0 && timeout < 0) {
- sr_err("Timer source without timeout would block indefinitely");
+ sr_err("Cannot create timer source without timeout.");
return SR_ERR_ARG;
}
- ret = sr_session_source_add_internal(session, timeout, cb, cb_data, fd);
- if (ret != SR_OK || fd < 0)
- return ret;
-
- return sr_session_source_poll_add(session, fd, fd, events);
+ return attach_fd_source(session, GINT_TO_POINTER(fd),
+ fd, events, timeout, cb, cb_data);
}
/**
GPollFD *pollfd, int timeout, sr_receive_data_callback cb,
void *cb_data)
{
- int ret;
-
if (!pollfd) {
sr_err("%s: pollfd was NULL", __func__);
return SR_ERR_ARG;
}
- ret = sr_session_source_add_internal(session,
- timeout, cb, cb_data, (gintptr)pollfd);
- if (ret != SR_OK)
- return ret;
-
- return sr_session_source_poll_add(session,
- (gintptr)pollfd, pollfd->fd, pollfd->events);
+ return attach_fd_source(session, pollfd, pollfd->fd,
+ pollfd->events, timeout, cb, cb_data);
}
/**
GIOChannel *channel, int events, int timeout,
sr_receive_data_callback cb, void *cb_data)
{
- int ret;
+ GPollFD pollfd;
- ret = sr_session_source_add_internal(session,
- timeout, cb, cb_data, (gintptr)channel);
- if (ret != SR_OK)
- return ret;
+ if (!channel) {
+ sr_err("%s: channel was NULL", __func__);
+ return SR_ERR_ARG;
+ }
+ /* We should be using g_io_create_watch(), but can't without
+ * changing the driver API, as the callback signature is different.
+ */
#ifdef G_OS_WIN32
- GPollFD p;
- g_io_channel_win32_make_pollfd(channel, events, &p);
-
- return sr_session_source_poll_add(session,
- (gintptr)channel, p.fd, p.events);
+ g_io_channel_win32_make_pollfd(channel, events, &pollfd);
#else
- return sr_session_source_poll_add(session, (gintptr)channel,
- g_io_channel_unix_get_fd(channel), events);
+ pollfd.fd = g_io_channel_unix_get_fd(channel);
+ pollfd.events = events;
#endif
+ return attach_fd_source(session, channel, pollfd.fd,
+ pollfd.events, timeout, cb, cb_data);
}
/**
* Remove the source identified by the specified poll object.
*
* @param session The session to use. Must not be NULL.
- * @param poll_object The channel for which the source should be removed.
+ * @param key The key by which the source is identified.
*
* @retval SR_OK Success
* @retval SR_ERR_BUG No event source for poll_object found.
*/
SR_PRIV int sr_session_source_remove_internal(struct sr_session *session,
- gintptr poll_object)
+ void *key)
{
- struct source *source;
- unsigned int i;
- int fd_index = 0;
+ GSource *source;
- for (i = 0; i < session->sources->len; ++i) {
- source = &g_array_index(session->sources, struct source, i);
-
- if (source->poll_object == poll_object) {
- if (source->num_fds > 0)
- g_array_remove_range(session->pollfds,
- fd_index, source->num_fds);
- g_array_remove_index(session->sources, i);
-
- sr_dbg("Removed event source %" G_GINTPTR_FORMAT ".",
- poll_object);
- return SR_OK;
- }
- fd_index += source->num_fds;
- }
- /* Trying to remove an already removed event source is problematic
+ source = g_hash_table_lookup(session->event_sources, key);
+ /*
+ * Trying to remove an already removed event source is problematic
* since the poll_object handle may have been reused in the meantime.
*/
- sr_warn("Cannot remove non-existing event source %"
- G_GINTPTR_FORMAT ".", poll_object);
-
- return SR_ERR_BUG;
-}
-
-SR_PRIV int sr_session_source_poll_remove(struct sr_session *session,
- gintptr poll_object, gintptr fd)
-{
- struct source *source;
- unsigned int i;
- int fd_index, k;
-
- source = NULL;
- fd_index = 0;
-
- /* Look up existing event source.
- */
- for (i = 0; i < session->sources->len; ++i) {
- source = &g_array_index(session->sources, struct source, i);
- if (source->poll_object == poll_object)
- break;
- fd_index += source->num_fds;
- }
if (!source) {
- sr_err("Cannot remove poll FD %" G_GINTPTR_FORMAT
- " from non-existing event source %" G_GINTPTR_FORMAT
- ".", fd, poll_object);
- return SR_ERR;
+ sr_warn("Cannot remove non-existing event source %p.", key);
+ return SR_ERR_BUG;
}
- /* Look up the FD in the poll set.
- */
- for (k = 0; k < source->num_fds; ++k)
- if (g_array_index(session->pollfds, GPollFD, fd_index + k)
- .fd == fd) {
+ g_source_destroy(source);
- g_array_remove_index(session->pollfds, fd_index + k);
- --source->num_fds;
-
- sr_dbg("Removed poll FD %" G_GINTPTR_FORMAT
- " from event source %" G_GINTPTR_FORMAT ".",
- fd, poll_object);
- return SR_OK;
- }
-
- sr_err("Cannot remove non-existing poll FD %" G_GINTPTR_FORMAT
- " from event source %" G_GINTPTR_FORMAT ".",
- fd, poll_object);
-
- return SR_ERR;
+ return SR_OK;
}
/**
*/
SR_API int sr_session_source_remove(struct sr_session *session, int fd)
{
- return sr_session_source_remove_internal(session, fd);
+ return sr_session_source_remove_internal(session, GINT_TO_POINTER(fd));
}
/**
sr_err("%s: pollfd was NULL", __func__);
return SR_ERR_ARG;
}
- return sr_session_source_remove_internal(session, (gintptr)pollfd);
+ return sr_session_source_remove_internal(session, pollfd);
}
/**
sr_err("%s: channel was NULL", __func__);
return SR_ERR_ARG;
}
- return sr_session_source_remove_internal(session, (gintptr)channel);
+ return sr_session_source_remove_internal(session, channel);
+}
+
+/** Unregister an event source that has been destroyed.
+ *
+ * This is intended to be called from a source's finalize() method.
+ *
+ * @param session The session to use. Must not be NULL.
+ * @param key The key used to identify @a source.
+ * @param source The source object that was destroyed.
+ *
+ * @retval SR_OK Success.
+ * @retval SR_ERR_BUG Event source for @a key does not match @a source.
+ */
+SR_PRIV int sr_session_source_destroyed(struct sr_session *session,
+ void *key, GSource *source)
+{
+ GSource *registered_source;
+
+ registered_source = g_hash_table_lookup(session->event_sources, key);
+ /*
+ * Trying to remove an already removed event source is problematic
+ * since the poll_object handle may have been reused in the meantime.
+ */
+ if (!registered_source) {
+ sr_err("No event source for key %p found.", key);
+ return SR_ERR_BUG;
+ }
+ if (registered_source != source) {
+ sr_err("Event source for key %p does not match"
+ " destroyed source.", key);
+ return SR_ERR_BUG;
+ }
+ g_hash_table_remove(session->event_sources, key);
+ /*
+ * Quit the main loop if we just removed the last event source.
+ * TODO: This may need an idle callback depending on when event
+ * sources are finalized. (The issue is remove followed by add
+ * within the same main loop iteration.)
+ */
+ if (session->main_loop
+ && g_hash_table_size(session->event_sources) == 0) {
+ sr_dbg("Stopping main loop...");
+ g_main_loop_quit(session->main_loop);
+ }
+ return SR_OK;
}
static void copy_src(struct sr_config *src, struct sr_datafeed_meta *meta_copy)
*
* Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
+ * Copyright (C) 2015 Daniel Elstner <daniel.kitta@gmail.com>
*
- * This program is free software; you can redistribute it and/or modify
+ * This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
typedef int libusb_os_handle;
#endif
+/** Custom GLib event source for libusb I/O.
+ * @internal
+ */
+struct usb_source {
+ GSource base;
+
+ int64_t timeout_us;
+ int64_t due_us;
+
+ /* Needed to keep track of installed sources */
+ struct sr_session *session;
+
+ struct libusb_context *usb_ctx;
+ GPtrArray *pollfds;
+};
+
+/** USB event source prepare() method.
+ */
+static gboolean usb_source_prepare(GSource *source, int *timeout)
+{
+ int64_t now_us, usb_due_us;
+ struct usb_source *usource;
+ struct timeval usb_timeout;
+ int remaining_ms;
+ int ret;
+
+ usource = (struct usb_source *)source;
+
+ ret = libusb_get_next_timeout(usource->usb_ctx, &usb_timeout);
+ if (G_UNLIKELY(ret < 0)) {
+ sr_err("Failed to get libusb timeout: %s",
+ libusb_error_name(ret));
+ }
+ now_us = g_source_get_time(source);
+
+ if (usource->due_us == 0) {
+ /* First-time initialization of the expiration time */
+ usource->due_us = now_us + usource->timeout_us;
+ }
+ if (ret == 1) {
+ usb_due_us = (int64_t)usb_timeout.tv_sec * G_USEC_PER_SEC
+ + usb_timeout.tv_usec + now_us;
+ if (usb_due_us < usource->due_us)
+ usource->due_us = usb_due_us;
+ }
+ if (usource->due_us != INT64_MAX)
+ remaining_ms = (MAX(0, usource->due_us - now_us) + 999) / 1000;
+ else
+ remaining_ms = -1;
+
+ *timeout = remaining_ms;
+
+ return (remaining_ms == 0);
+}
+
+/** USB event source check() method.
+ */
+static gboolean usb_source_check(GSource *source)
+{
+ struct usb_source *usource;
+ GPollFD *pollfd;
+ unsigned int revents;
+ unsigned int i;
+
+ usource = (struct usb_source *)source;
+ revents = 0;
+
+ for (i = 0; i < usource->pollfds->len; i++) {
+ pollfd = g_ptr_array_index(usource->pollfds, i);
+ revents |= pollfd->revents;
+ }
+ return (revents != 0 || (usource->due_us != INT64_MAX
+ && usource->due_us <= g_source_get_time(source)));
+}
+
+/** USB event source dispatch() method.
+ */
+static gboolean usb_source_dispatch(GSource *source,
+ GSourceFunc callback, void *user_data)
+{
+ struct usb_source *usource;
+ GPollFD *pollfd;
+ unsigned int revents;
+ unsigned int i;
+ gboolean keep;
+
+ usource = (struct usb_source *)source;
+ revents = 0;
+ /*
+ * This is somewhat arbitrary, but drivers use revents to distinguish
+ * actual I/O from timeouts. When we remove the user timeout from the
+ * driver API, this will no longer be needed.
+ */
+ for (i = 0; i < usource->pollfds->len; i++) {
+ pollfd = g_ptr_array_index(usource->pollfds, i);
+ revents |= pollfd->revents;
+ }
+ if (revents != 0)
+ sr_spew("%s: revents 0x%.2X", __func__, revents);
+ else
+ sr_spew("%s: timed out", __func__);
+
+ if (!callback) {
+ sr_err("Callback not set, cannot dispatch event.");
+ return G_SOURCE_REMOVE;
+ }
+ keep = (*(sr_receive_data_callback)callback)(-1, revents, user_data);
+
+ if (G_LIKELY(keep) && G_LIKELY(!g_source_is_destroyed(source))) {
+ if (usource->timeout_us >= 0)
+ usource->due_us = g_source_get_time(source)
+ + usource->timeout_us;
+ else
+ usource->due_us = INT64_MAX;
+ }
+ return keep;
+}
+
+/** USB event source finalize() method.
+ */
+static void usb_source_finalize(GSource *source)
+{
+ struct usb_source *usource;
+
+ usource = (struct usb_source *)source;
+
+ sr_spew("%s", __func__);
+
+ libusb_set_pollfd_notifiers(usource->usb_ctx, NULL, NULL, NULL);
+
+ g_ptr_array_unref(usource->pollfds);
+ usource->pollfds = NULL;
+
+ sr_session_source_destroyed(usource->session,
+ usource->usb_ctx, source);
+}
+
+/** Callback invoked when a new libusb FD should be added to the poll set.
+ */
+static LIBUSB_CALL void usb_pollfd_added(libusb_os_handle fd,
+ short events, void *user_data)
+{
+ struct usb_source *usource;
+ GPollFD *pollfd;
+
+ usource = user_data;
+
+ pollfd = g_slice_new(GPollFD);
+#ifdef G_OS_WIN32
+ events = G_IO_IN;
+#endif
+ pollfd->fd = (gintptr)fd;
+ pollfd->events = events;
+ pollfd->revents = 0;
+
+ g_ptr_array_add(usource->pollfds, pollfd);
+ g_source_add_poll((GSource *)usource, pollfd);
+}
+
+/** Callback invoked when a libusb FD should be removed from the poll set.
+ */
+static LIBUSB_CALL void usb_pollfd_removed(libusb_os_handle fd, void *user_data)
+{
+ struct usb_source *usource;
+ GPollFD *pollfd;
+ unsigned int i;
+
+ usource = user_data;
+
+ /* It's likely that the removed poll FD is at the end.
+ */
+ for (i = usource->pollfds->len; G_LIKELY(i > 0); i--) {
+ pollfd = g_ptr_array_index(usource->pollfds, i - 1);
+
+ if ((libusb_os_handle)pollfd->fd == fd) {
+ g_source_remove_poll((GSource *)usource, pollfd);
+ g_ptr_array_remove_index_fast(usource->pollfds, i - 1);
+ return;
+ }
+ }
+ sr_err("FD to be removed (%" G_GINTPTR_FORMAT
+ ") not found in event source poll set.", (gintptr)fd);
+}
+
+/** Destroy notify callback for FDs maintained by the USB event source.
+ */
+static void usb_source_free_pollfd(void *data)
+{
+ g_slice_free(GPollFD, data);
+}
+
+/** Create an event source for libusb I/O.
+ *
+ * TODO: The combination of the USB I/O source with a user timeout is
+ * conceptually broken. The user timeout supplied here is completely
+ * unrelated to I/O -- the actual I/O timeout is set when submitting
+ * a USB transfer.
+ * The sigrok drivers generally use the timeout to poll device state.
+ * Usually, this polling can be sensibly done only when there is no
+ * active USB transfer -- i.e. it's actually mutually exclusive with
+ * waiting for transfer completion.
+ * Thus, the user timeout should be removed from the USB event source
+ * API at some point. Instead, drivers should install separate timer
+ * event sources for their polling needs.
+ *
+ * @param session The session the event source belongs to.
+ * @param usb_ctx The libusb context for which to handle events.
+ * @param timeout_ms The timeout interval in ms, or -1 to wait indefinitely.
+ * @return A new event source object, or NULL on failure.
+ */
+static GSource *usb_source_new(struct sr_session *session,
+ struct libusb_context *usb_ctx, int timeout_ms)
+{
+ static GSourceFuncs usb_source_funcs = {
+ .prepare = &usb_source_prepare,
+ .check = &usb_source_check,
+ .dispatch = &usb_source_dispatch,
+ .finalize = &usb_source_finalize
+ };
+ GSource *source;
+ struct usb_source *usource;
+ const struct libusb_pollfd **upollfds, **upfd;
+
+ upollfds = libusb_get_pollfds(usb_ctx);
+ if (!upollfds) {
+ sr_err("Failed to get libusb file descriptors.");
+ return NULL;
+ }
+ source = g_source_new(&usb_source_funcs, sizeof(struct usb_source));
+ usource = (struct usb_source *)source;
+
+ g_source_set_name(source, "usb");
+
+ if (timeout_ms >= 0) {
+ usource->timeout_us = 1000 * (int64_t)timeout_ms;
+ usource->due_us = 0;
+ } else {
+ usource->timeout_us = -1;
+ usource->due_us = INT64_MAX;
+ }
+ usource->session = session;
+ usource->usb_ctx = usb_ctx;
+ usource->pollfds = g_ptr_array_new_full(8, &usb_source_free_pollfd);
+
+ for (upfd = upollfds; *upfd != NULL; upfd++)
+ usb_pollfd_added((*upfd)->fd, (*upfd)->events, usource);
+
+#if (LIBUSB_API_VERSION >= 0x01000104)
+ libusb_free_pollfds(upollfds);
+#else
+ free(upollfds);
+#endif
+ libusb_set_pollfd_notifiers(usb_ctx,
+ &usb_pollfd_added, &usb_pollfd_removed, usource);
+
+ return source;
+}
+
/**
* Find USB devices according to a connection string.
*
sr_dbg("Closed USB device %d.%d.", usb->bus, usb->address);
}
-static LIBUSB_CALL void usb_pollfd_added(libusb_os_handle fd,
- short events, void *user_data)
-{
- struct sr_session *session;
- gintptr tag;
-
- session = user_data;
- tag = (gintptr)session->ctx->libusb_ctx;
-#ifdef G_OS_WIN32
- events = G_IO_IN;
-#endif
- sr_session_source_poll_add(session, tag, (gintptr)fd, events);
-}
-
-static LIBUSB_CALL void usb_pollfd_removed(libusb_os_handle fd, void *user_data)
-{
- struct sr_session *session;
- gintptr tag;
-
- session = user_data;
- tag = (gintptr)session->ctx->libusb_ctx;
-
- sr_session_source_poll_remove(session, tag, (gintptr)fd);
-}
-
SR_PRIV int usb_source_add(struct sr_session *session, struct sr_context *ctx,
int timeout, sr_receive_data_callback cb, void *cb_data)
{
- const struct libusb_pollfd **pollfds;
- gintptr tag;
- int i;
+ GSource *source;
int ret;
- int events;
- if (ctx->usb_source_present) {
- sr_err("A USB event source is already present.");
- return SR_ERR;
- }
- pollfds = libusb_get_pollfds(ctx->libusb_ctx);
- if (!pollfds) {
- sr_err("Failed to get libusb file descriptors.");
+ source = usb_source_new(session, ctx->libusb_ctx, timeout);
+ if (!source)
return SR_ERR;
- }
- tag = (gintptr)ctx->libusb_ctx;
- ret = sr_session_source_add_internal(session,
- timeout, cb, cb_data, tag);
- ctx->usb_source_present = (ret == SR_OK);
+ g_source_set_callback(source, (GSourceFunc)cb, cb_data, NULL);
- for (i = 0; ret == SR_OK && pollfds[i]; ++i) {
-#ifdef G_OS_WIN32
- events = G_IO_IN;
-#else
- events = pollfds[i]->events;
-#endif
- ret = sr_session_source_poll_add(session, tag,
- (gintptr)pollfds[i]->fd, events);
- }
-#if (LIBUSB_API_VERSION >= 0x01000104)
- libusb_free_pollfds(pollfds);
-#else
- free(pollfds);
-#endif
- if (ret != SR_OK)
- return ret;
+ ret = sr_session_source_add_internal(session, ctx->libusb_ctx, source);
+ g_source_unref(source);
- libusb_set_pollfd_notifiers(ctx->libusb_ctx,
- &usb_pollfd_added, &usb_pollfd_removed, session);
-
- return SR_OK;
+ return ret;
}
SR_PRIV int usb_source_remove(struct sr_session *session, struct sr_context *ctx)
{
- ctx->usb_source_present = FALSE;
-
- libusb_set_pollfd_notifiers(ctx->libusb_ctx, NULL, NULL, NULL);
-
- return sr_session_source_remove_internal(session,
- (gintptr)ctx->libusb_ctx);
+ return sr_session_source_remove_internal(session, ctx->libusb_ctx);
}
SR_PRIV int usb_get_port_path(libusb_device *dev, char *path, int path_len)
projects / libsigrok.git / commitdiff