X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=session.c;h=1cf4170e220a1904ee798cb0161a29e67fcbef90;hb=8819bf5a960c37561e2bbbffa2685ec477938083;hp=2ea7dbef29e50fcc64ab2c9876f2f62e8767e0de;hpb=efdecf4c0553ce00ea2a6365212f5fe305496fed;p=libsigrok.git

diff --git a/session.c b/session.c
index 2ea7dbef..1cf4170e 100644
--- a/session.c
+++ b/session.c
@@ -25,14 +25,14 @@
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
 
-/* Message logging helpers with driver-specific prefix string. */
-#define DRIVER_LOG_DOMAIN "session: "
-#define sr_log(l, s, args...) sr_log(l, DRIVER_LOG_DOMAIN s, ## args)
-#define sr_spew(s, args...) sr_spew(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_dbg(s, args...) sr_dbg(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_info(s, args...) sr_info(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN s, ## args)
+/* Message logging helpers with subsystem-specific prefix string. */
+#define LOG_PREFIX "session: "
+#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
+#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
+#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
+#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
+#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
+#define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
 
 /**
  * @file
@@ -84,6 +84,7 @@ SR_API struct sr_session *sr_session_new(void)
 	}
 
 	session->source_timeout = -1;
+	session->running = FALSE;
 	session->abort_session = FALSE;
 	g_mutex_init(&session->stop_mutex);
 
@@ -131,7 +132,7 @@ SR_API int sr_session_dev_remove_all(void)
 		return SR_ERR_BUG;
 	}
 
-	g_slist_free_full(session->devs, (GDestroyNotify)sr_dev_close);
+	g_slist_free(session->devs);
 	session->devs = NULL;
 
 	return SR_OK;
@@ -148,6 +149,7 @@ SR_API int sr_session_dev_remove_all(void)
  */
 SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
 {
+	int ret;
 
 	if (!sdi) {
 		sr_err("%s: sdi was NULL", __func__);
@@ -176,6 +178,40 @@ SR_API int sr_session_dev_add(const struct sr_dev_inst *sdi)
 
 	session->devs = g_slist_append(session->devs, (gpointer)sdi);
 
+	if (session->running) {
+		/* Adding a device to a running session. Start acquisition
+		 * on that device now. */
+		if ((ret = sdi->driver->dev_acquisition_start(sdi,
+						(void *)sdi)) != SR_OK)
+			sr_err("Failed to start acquisition of device in "
+					"running session: %d", ret);
+	}
+
+	return SR_OK;
+}
+
+/**
+ * List all device instances attached to the current session.
+ *
+ * @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
+ *                to a struct sr_dev_inst *.
+ *                The list must be freed by the caller, but not the
+ *                elements pointed to.
+ *
+ * @return SR_OK upon success, SR_ERR upon invalid arguments.
+ */
+SR_API int sr_session_dev_list(GSList **devlist)
+{
+
+	*devlist = NULL;
+
+	if (!session)
+		return SR_ERR;
+
+	*devlist = g_slist_copy(session->devs);
+
 	return SR_OK;
 }
 
@@ -232,38 +268,55 @@ SR_API int sr_session_datafeed_callback_add(sr_datafeed_callback_t cb, void *cb_
 	return SR_OK;
 }
 
-static int sr_session_run_poll(void)
+/**
+ * Call every device in the session's callback.
+ *
+ * For sessions not driven by select loops such as sr_session_run(),
+ * but driven by another scheduler, this can be used to poll the devices
+ * from within that scheduler.
+ *
+ * @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
+ *              can be used as a select loop.
+ *              If FALSE, all sources have their callback run, regardless
+ *              of file descriptor or timeout status.
+ *
+ * @return SR_OK upon success, SR_ERR on errors.
+ */
+static int sr_session_iteration(gboolean block)
 {
 	unsigned int i;
 	int ret;
 
-	while (session->num_sources > 0) {
-		ret = g_poll(session->pollfds, session->num_sources,
-				session->source_timeout);
-		for (i = 0; i < session->num_sources; i++) {
-			if (session->pollfds[i].revents > 0 || (ret == 0
-				&& session->source_timeout == session->sources[i].timeout)) {
-				/*
-				 * Invoke the source's callback on an event,
-				 * or if the poll timed out and this source
-				 * asked for that timeout.
-				 */
-				if (!session->sources[i].cb(session->pollfds[i].fd,
-						session->pollfds[i].revents,
-						session->sources[i].cb_data))
-					sr_session_source_remove(session->sources[i].poll_object);
-			}
+	ret = g_poll(session->pollfds, session->num_sources,
+			block ? session->source_timeout : 0);
+	for (i = 0; i < session->num_sources; i++) {
+		if (session->pollfds[i].revents > 0 || (ret == 0
+			&& session->source_timeout == session->sources[i].timeout)) {
 			/*
-			 * 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.
+			 * Invoke the source's callback on an event,
+			 * or if the poll timed out and this source
+			 * asked for that timeout.
 			 */
-			g_mutex_lock(&session->stop_mutex);
-			if (session->abort_session)
-				sr_session_stop_sync();
-			g_mutex_unlock(&session->stop_mutex);
+			if (!session->sources[i].cb(session->pollfds[i].fd,
+					session->pollfds[i].revents,
+					session->sources[i].cb_data))
+				sr_session_source_remove(session->sources[i].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.
+		 */
+		g_mutex_lock(&session->stop_mutex);
+		if (session->abort_session) {
+			sr_session_stop_sync();
+			/* But once is enough. */
+			session->abort_session = FALSE;
+		}
+		g_mutex_unlock(&session->stop_mutex);
 	}
 
 	return SR_OK;
@@ -301,7 +354,7 @@ SR_API int sr_session_start(void)
 		sdi = l->data;
 		if ((ret = sdi->driver->dev_acquisition_start(sdi, sdi)) != SR_OK) {
 			sr_err("%s: could not start an acquisition "
-			       "(%d)", __func__, ret);
+			       "(%s)", __func__, sr_strerror(ret));
 			break;
 		}
 	}
@@ -330,6 +383,7 @@ SR_API int sr_session_run(void)
 		       "cannot be run without devices.", __func__);
 		return SR_ERR_BUG;
 	}
+	session->running = TRUE;
 
 	sr_info("Running.");
 
@@ -340,7 +394,8 @@ SR_API int sr_session_run(void)
 			session->sources[0].cb(-1, 0, session->sources[0].cb_data);
 	} else {
 		/* Real sources, use g_poll() main loop. */
-		sr_session_run_poll();
+		while (session->num_sources)
+			sr_session_iteration(TRUE);
 	}
 
 	return SR_OK;
@@ -356,6 +411,8 @@ SR_API int sr_session_run(void)
  * resources that the session thread will try to use.
  *
  * @return SR_OK upon success, SR_ERR_BUG if no session exists.
+ *
+ * @private
  */
 SR_PRIV int sr_session_stop_sync(void)
 {
@@ -376,15 +433,7 @@ SR_PRIV int sr_session_stop_sync(void)
 				sdi->driver->dev_acquisition_stop(sdi, sdi);
 		}
 	}
-
-	/*
-	 * Some sources may not be necessarily associated with a device.
-	 * Those sources may still be present even after stopping all devices.
-	 * We need to make sure all sources are removed, or we risk running the
-	 * session in an infinite loop.
-	 */
-	while (session->num_sources)
-		sr_session_source_remove(session->sources[0].poll_object);
+	session->running = FALSE;
 
 	return SR_OK;
 }