Implement PID tracker content listing

[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c

diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index c2210f48aa484c94393003e9f5b782ddbc5770c4..004b0ccebf1c7b24e49674e2f3d66d53bfde7abe 100644 (file)
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -1990,6 +1990,51 @@ end:
        return ret;
 }
 
        return ret;
 }
 

+/*
+ * List PIDs in the tracker.
+ *
+ * @enabled is set to whether the PID tracker is enabled.
+ * @pids is set to an allocated array of PIDs currently tracked. On
+ * success, @pids must be freed by the caller.
+ * @nr_pids is set to the number of entries contained by the @pids array.
+ *
+ * Returns 0 on success, else a negative LTTng error code.
+ */
+int lttng_list_tracker_pids(struct lttng_handle *handle,
+               int *_enabled, int32_t **_pids, size_t *_nr_pids)
+{
+       int ret, enabled = 1;
+       struct lttcomm_session_msg lsm;
+       size_t nr_pids;
+       int32_t *pids;
+
+       if (handle == NULL) {
+               return -LTTNG_ERR_INVALID;
+       }
+
+       memset(&lsm, 0, sizeof(lsm));
+       lsm.cmd_type = LTTNG_LIST_TRACKER_PIDS;
+       lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+                       sizeof(lsm.session.name));
+       lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+       ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pids);
+       if (ret < 0) {
+               return ret;
+       }
+       nr_pids = ret / sizeof(int32_t);
+       if (nr_pids == 1 && pids[0] == -1) {
+               free(pids);
+               pids = NULL;
+               enabled = 0;
+               nr_pids = 0;
+       }
+       *_enabled = enabled;
+       *_pids = pids;
+       *_nr_pids = nr_pids;
+       return 0;
+}
+

 /*
  * lib constructor
  */
 /*
  * lib constructor
  */