X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fsession.c;h=dc8fd4fbeaffc2ce3c78cdeabcd5156f30c44363;hb=db560903d196c39bceeaa543317fa602a02b51ac;hp=d8a3b00b5efabe157ab546498bee39139b249853;hpb=155b680da482cea2381becb73c51cfb838bff31e;p=libsigrok.git

diff --git a/src/session.c b/src/session.c
index d8a3b00b..dc8fd4fb 100644
--- a/src/session.c
+++ b/src/session.c
@@ -61,10 +61,13 @@ struct datafeed_callback {
 
 /**
  * Create a new session.
- * Currently, there can be only one session at a time within the same process.
+ *
+ * @param new_session This will contain a pointer to the newly created
+ *                    session if the return value is SR_OK, otherwise the value
+ *                    is undefined and should not be used. Must not be NULL.
  *
  * @retval SR_OK Success.
- * @retval SR_ERR_BUG A session exists already.
+ * @retval SR_ERR_ARG Invalid argument.
  *
  * @since 0.4.0
  */
@@ -72,6 +75,9 @@ SR_API int sr_session_new(struct sr_session **new_session)
 {
 	struct sr_session *session;
 
+	if (!new_session)
+		return SR_ERR_ARG;
+
 	session = g_malloc0(sizeof(struct sr_session));
 
 	session->source_timeout = -1;
@@ -88,6 +94,8 @@ SR_API int sr_session_new(struct sr_session **new_session)
  * Destroy a session.
  * This frees up all memory used by the session.
  *
+ * @param session The session to destroy. Must not be NULL.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR_ARG Invalid session passed.
  *
@@ -116,6 +124,8 @@ SR_API int sr_session_destroy(struct sr_session *session)
  * The session itself (i.e., the struct sr_session) is not free'd and still
  * exists after this function returns.
  *
+ * @param session The session to use. Must not be NULL.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR_BUG Invalid session passed.
  *
@@ -145,6 +155,7 @@ SR_API int sr_session_dev_remove_all(struct sr_session *session)
 /**
  * Add a device instance to a session.
  *
+ * @param session The session to add to. Must not be NULL.
  * @param sdi The device instance to add to a session. Must not
  *            be NULL. Also, sdi->driver and sdi->driver->dev_open must
  *            not be NULL.
@@ -178,8 +189,6 @@ SR_API int sr_session_dev_add(struct sr_session *session,
 
 	/* If sdi->driver is NULL, this is a virtual device. */
 	if (!sdi->driver) {
-		sr_dbg("%s: sdi->driver was NULL, this seems to be "
-		       "a virtual device; continuing", __func__);
 		/* Just add the device, don't run dev_open(). */
 		session->devs = g_slist_append(session->devs, (gpointer)sdi);
 		sdi->session = session;
@@ -218,6 +227,7 @@ SR_API int sr_session_dev_add(struct sr_session *session,
 /**
  * List all device instances attached to a session.
  *
+ * @param session The session to use. Must not be NULL.
  * @param devlist A pointer where the device instance list will be
  *                stored on return. If no devices are in the session,
  *                this will be NULL. Each element in the list points
@@ -246,6 +256,8 @@ SR_API int sr_session_dev_list(struct sr_session *session, GSList **devlist)
 /**
  * Remove all datafeed callbacks in a session.
  *
+ * @param session The session to use. Must not be NULL.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR_ARG Invalid session passed.
  *
@@ -267,6 +279,7 @@ SR_API int sr_session_datafeed_callback_remove_all(struct sr_session *session)
 /**
  * Add a datafeed callback to a session.
  *
+ * @param session The session to use. Must not be NULL.
  * @param cb Function to call when a chunk of data is received.
  *           Must not be NULL.
  * @param cb_data Opaque pointer passed in by the caller.
@@ -322,6 +335,7 @@ SR_API int sr_session_trigger_set(struct sr_session *session, struct sr_trigger
  * but driven by another scheduler, this can be used to poll the devices
  * from within that scheduler.
  *
+ * @param session The session to use. Must not be NULL.
  * @param block If TRUE, this call will wait for any of the session's
  *              sources to fire an event on the file descriptors, or
  *              any of their timeouts to activate. In other words, this
@@ -410,6 +424,8 @@ static int verify_trigger(struct sr_trigger *trigger)
 /**
  * Start a session.
  *
+ * @param session The session to use. Must not be NULL.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR_ARG Invalid session passed.
  *
@@ -418,8 +434,9 @@ static int verify_trigger(struct sr_trigger *trigger)
 SR_API int sr_session_start(struct sr_session *session)
 {
 	struct sr_dev_inst *sdi;
-	GSList *l;
-	int ret;
+	struct sr_channel *ch;
+	GSList *l, *c;
+	int enabled_channels, ret;
 
 	if (!session) {
 		sr_err("%s: session was NULL", __func__);
@@ -440,6 +457,21 @@ SR_API int sr_session_start(struct sr_session *session)
 	ret = SR_OK;
 	for (l = session->devs; l; l = l->next) {
 		sdi = l->data;
+		enabled_channels = 0;
+		for (c = sdi->channels; c; c = c->next) {
+			ch = c->data;
+			if (ch->enabled) {
+				enabled_channels++;
+				break;
+			}
+		}
+		if (enabled_channels == 0) {
+			ret = SR_ERR;
+			sr_err("%s instance %d has no enabled channels!",
+					sdi->driver->name, sdi->index);
+			break;
+		}
+
 		if ((ret = sr_config_commit(sdi)) != SR_OK) {
 			sr_err("Failed to commit device settings before "
 			       "starting acquisition (%s)", sr_strerror(ret));
@@ -460,6 +492,8 @@ SR_API int sr_session_start(struct sr_session *session)
 /**
  * Run a session.
  *
+ * @param session The session to use. Must not be NULL.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR_ARG Invalid session passed.
  *
@@ -505,6 +539,8 @@ SR_API int sr_session_run(struct sr_session *session)
  * 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.
  *
@@ -545,6 +581,8 @@ SR_PRIV int sr_session_stop_sync(struct sr_session *session)
  * to wait for the session thread to return before assuming that the session is
  * completely decommissioned.
  *
+ * @param session The session to use. Must not be NULL.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR_ARG Invalid session passed.
  *
@@ -651,6 +689,7 @@ SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
 /**
  * Add an event source for a file descriptor.
  *
+ * @param session The session to use. Must not be NULL.
  * @param pollfd The GPollFD.
  * @param[in] timeout Max time to wait before the callback is called,
  *              ignored if 0.
@@ -708,6 +747,7 @@ static int _sr_session_source_add(struct sr_session *session, GPollFD *pollfd,
 /**
  * Add an event source for a file descriptor.
  *
+ * @param session The session to use. Must not be NULL.
  * @param fd The file descriptor.
  * @param events Events to check for.
  * @param timeout Max time to wait before the callback is called, ignored if 0.
@@ -725,8 +765,6 @@ SR_API int sr_session_source_add(struct sr_session *session, int fd,
 {
 	GPollFD p;
 
-	(void) session;
-
 	p.fd = fd;
 	p.events = events;
 
@@ -736,6 +774,7 @@ SR_API int sr_session_source_add(struct sr_session *session, int fd,
 /**
  * Add an event source for a GPollFD.
  *
+ * @param session The session to use. Must not be NULL.
  * @param pollfd The GPollFD.
  * @param timeout Max time to wait before the callback is called, ignored if 0.
  * @param cb Callback function to add. Must not be NULL.
@@ -751,8 +790,6 @@ SR_API int sr_session_source_add_pollfd(struct sr_session *session,
 		GPollFD *pollfd, int timeout, sr_receive_data_callback cb,
 		void *cb_data)
 {
-	(void) session;
-
 	return _sr_session_source_add(session, pollfd, timeout, cb,
 				      cb_data, (gintptr)pollfd);
 }
@@ -760,6 +797,7 @@ SR_API int sr_session_source_add_pollfd(struct sr_session *session,
 /**
  * Add an event source for a GIOChannel.
  *
+ * @param session The session to use. Must not be NULL.
  * @param channel The GIOChannel.
  * @param events Events to poll on.
  * @param timeout Max time to wait before the callback is called, ignored if 0.
@@ -778,8 +816,6 @@ SR_API int sr_session_source_add_channel(struct sr_session *session,
 {
 	GPollFD p;
 
-	(void) session;
-
 #ifdef _WIN32
 	g_io_channel_win32_make_pollfd(channel, events, &p);
 #else
@@ -795,6 +831,7 @@ SR_API int sr_session_source_add_channel(struct sr_session *session,
  *
  * @todo Add more error checks and logging.
  *
+ * @param session The session to use. Must not be NULL.
  * @param poll_object The channel for which the source should be removed.
  *
  * @retval SR_OK Success
@@ -852,6 +889,7 @@ static int _sr_session_source_remove(struct sr_session *session, gintptr poll_ob
 /**
  * Remove the source belonging to the specified file descriptor.
  *
+ * @param session The session to use. Must not be NULL.
  * @param fd The file descriptor for which the source should be removed.
  *
  * @retval SR_OK Success
@@ -863,14 +901,13 @@ static int _sr_session_source_remove(struct sr_session *session, gintptr poll_ob
  */
 SR_API int sr_session_source_remove(struct sr_session *session, int fd)
 {
-	(void) session;
-
 	return _sr_session_source_remove(session, (gintptr)fd);
 }
 
 /**
  * Remove the source belonging to the specified poll descriptor.
  *
+ * @param session The session to use. Must not be NULL.
  * @param pollfd The poll descriptor for which the source should be removed.
  *
  * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
@@ -882,14 +919,13 @@ SR_API int sr_session_source_remove(struct sr_session *session, int fd)
 SR_API int sr_session_source_remove_pollfd(struct sr_session *session,
 		GPollFD *pollfd)
 {
-	(void) session;
-
 	return _sr_session_source_remove(session, (gintptr)pollfd);
 }
 
 /**
  * Remove the source belonging to the specified channel.
  *
+ * @param session The session to use. Must not be NULL.
  * @param channel The channel for which the source should be removed.
  *
  * @retval SR_OK Success.
@@ -902,8 +938,6 @@ SR_API int sr_session_source_remove_pollfd(struct sr_session *session,
 SR_API int sr_session_source_remove_channel(struct sr_session *session,
 		GIOChannel *channel)
 {
-	(void) session;
-
 	return _sr_session_source_remove(session, (gintptr)channel);
 }