]> sigrok.org Git - libsigrok.git/blobdiff - session.c
Bump libzip requirement to >= 0.10.
[libsigrok.git] / session.c
index 266207259ca3c82e9c42c76208af3ae8afb88880..1cf4170e220a1904ee798cb0161a29e67fcbef90 100644 (file)
--- a/session.c
+++ b/session.c
 #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);
 
@@ -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;
 }