X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=session.c;h=8048fdfd7b22e00dc3294395076d23b8672a0dd4;hb=2f8701d112cc1c4b61b36fe4c7096431833a8c9d;hp=06d4a3b4f68bdfec6d10616632f663bb0f597f2e;hpb=31ccebc4925d245fed02545415ce3ee14055d897;p=libsigrok.git

diff --git a/session.c b/session.c
index 06d4a3b4..8048fdfd 100644
--- a/session.c
+++ b/session.c
@@ -33,7 +33,7 @@ struct source {
 	int events;
 	int timeout;
 	sr_receive_data_callback_t cb;
-	void *user_data;
+	void *cb_data;
 };
 
 /* There can only be one session at a time. */
@@ -127,20 +127,25 @@ SR_API int sr_session_dev_add(struct sr_dev *dev)
 		return SR_ERR_ARG;
 	}
 
+	if (!session) {
+		sr_err("session: %s: session was NULL", __func__);
+		return SR_ERR_BUG;
+	}
+
+	/* If dev->driver is NULL, this is a virtual device. */
 	if (!dev->driver) {
-		sr_err("session: %s: dev->driver was NULL", __func__);
-		return SR_ERR_ARG;
+		sr_dbg("session: %s: dev->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, dev);
+		return SR_OK;
 	}
 
+	/* dev->driver is non-NULL (i.e. we have a real device). */
 	if (!dev->driver->dev_open) {
 		sr_err("session: %s: dev->driver->dev_open was NULL",
 		       __func__);
-		return SR_ERR_ARG;
-	}
-
-	if (!session) {
-		sr_err("session: %s: session was NULL", __func__);
-		return SR_ERR; /* TODO: SR_ERR_BUG? */
+		return SR_ERR_BUG;
 	}
 
 	if ((ret = dev->driver->dev_open(dev->driver_index)) != SR_OK) {
@@ -175,6 +180,7 @@ SR_API int sr_session_datafeed_callback_clear(void)
  * Add a datafeed callback to the current session.
  *
  * @param cb Function to call when a chunk of data is received.
+ *           Must not be NULL.
  *
  * @return SR_OK upon success, SR_ERR_BUG if no session exists.
  */
@@ -185,7 +191,10 @@ SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb)
 		return SR_ERR_BUG;
 	}
 
-	/* TODO: Is 'cb' allowed to be NULL? */
+	if (!cb) {
+		sr_err("session: %s: cb was NULL", __func__);
+		return SR_ERR_ARG;
+	}
 
 	session->datafeed_callbacks =
 	    g_slist_append(session->datafeed_callbacks, cb);
@@ -233,7 +242,7 @@ static int sr_session_run_poll(void)
 				 * asked for that timeout.
 				 */
 				if (!sources[i].cb(fds[i].fd, fds[i].revents,
-						  sources[i].user_data))
+						  sources[i].cb_data))
 					sr_session_source_remove(sources[i].fd);
 			}
 		}
@@ -259,14 +268,14 @@ SR_API int sr_session_start(void)
 	if (!session) {
 		sr_err("session: %s: session was NULL; a session must be "
 		       "created first, before starting it.", __func__);
-		return SR_ERR; /* TODO: SR_ERR_BUG? */
+		return SR_ERR_BUG;
 	}
 
 	if (!session->devs) {
 		/* TODO: Actually the case? */
 		sr_err("session: %s: session->devs was NULL; a session "
 		       "cannot be started without devices.", __func__);
-		return SR_ERR; /* TODO: SR_ERR_BUG? */
+		return SR_ERR_BUG;
 	}
 
 	/* TODO: Check driver_index validity? */
@@ -318,7 +327,7 @@ SR_API int sr_session_run(void)
 	if (num_sources == 1 && sources[0].fd == -1) {
 		/* Dummy source, freewheel over it. */
 		while (session->running)
-			sources[0].cb(-1, 0, sources[0].user_data);
+			sources[0].cb(-1, 0, sources[0].cb_data);
 	} else {
 		/* Real sources, use g_poll() main loop. */
 		sr_session_run_poll();
@@ -434,11 +443,6 @@ SR_PRIV int sr_session_send(struct sr_dev *dev,
 		return SR_ERR_ARG;
 	}
 
-	if (!dev->driver) {
-		sr_err("session: %s: dev->driver was NULL", __func__);
-		return SR_ERR_ARG;
-	}
-
 	if (!packet) {
 		sr_err("session: %s: packet was NULL", __func__);
 		return SR_ERR_ARG;
@@ -463,14 +467,14 @@ SR_PRIV int sr_session_send(struct sr_dev *dev,
  * @param fd TODO.
  * @param events TODO.
  * @param timeout TODO.
- * @param cb TODO.
- * @param user_data TODO.
+ * @param cb Callback function to add. Must not be NULL.
+ * @param cb_data Data for the callback function. Can be NULL.
  *
  * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
  *         SR_ERR_MALLOC upon memory allocation errors.
  */
 SR_API int sr_session_source_add(int fd, int events, int timeout,
-		sr_receive_data_callback_t cb, void *user_data)
+		sr_receive_data_callback_t cb, void *cb_data)
 {
 	struct source *new_sources, *s;
 
@@ -479,7 +483,7 @@ SR_API int sr_session_source_add(int fd, int events, int timeout,
 		return SR_ERR_ARG;
 	}
 
-	/* Note: user_data can be NULL, that's not a bug. */
+	/* Note: cb_data can be NULL, that's not a bug. */
 
 	new_sources = g_try_malloc0(sizeof(struct source) * (num_sources + 1));
 	if (!new_sources) {
@@ -498,7 +502,7 @@ SR_API int sr_session_source_add(int fd, int events, int timeout,
 	s->events = events;
 	s->timeout = timeout;
 	s->cb = cb;
-	s->user_data = user_data;
+	s->cb_data = cb_data;
 	sources = new_sources;
 
 	if (timeout != source_timeout && timeout > 0
@@ -526,7 +530,7 @@ SR_API int sr_session_source_remove(int fd)
 
 	if (!sources) {
 		sr_err("session: %s: sources was NULL", __func__);
-		return SR_ERR_BUG; /* TODO: Other? */
+		return SR_ERR_BUG;
 	}
 
 	/* TODO: Check if 'fd' valid. */