Fix: prevent calling adding the same trace recursively

[babeltrace.git] / formats / lttng-live / lttng-live-comm.c

diff --git a/formats/lttng-live/lttng-live-comm.c b/formats/lttng-live/lttng-live-comm.c
index b61371fc5dba65523eb46f5f1e69b391d2103990..e08926380efab45e306a01ec59607012f51fbc90 100644 (file)
--- a/formats/lttng-live/lttng-live-comm.c
+++ b/formats/lttng-live/lttng-live-comm.c
@@ -1499,6 +1499,12 @@ int add_one_trace(struct lttng_live_ctx *ctx,
                ret = 0;
                goto end;
        }
+       /*
+        * add_one_trace can be called recursively if during the
+        * bt_context_add_trace call we need to fetch new streams, so we need to
+        * prevent a recursive call to process our current trace.
+        */
+       trace->in_use = 1;
 
        BT_INIT_LIST_HEAD(&mmap_list.head);
 
@@ -1561,7 +1567,6 @@ int add_one_trace(struct lttng_live_ctx *ctx,
        }
 
        trace->trace_id = ret;
-       trace->in_use = 1;
        printf_verbose("Trace now in use, id = %d\n", trace->trace_id);
 
        goto end;
@@ -1630,9 +1635,13 @@ int add_traces(struct lttng_live_ctx *ctx)
        GHashTableIter it;
        gpointer key;
        gpointer value;
+       unsigned int nr_traces;
 
        printf_verbose("Begin add traces\n");
 
+retry:
+       nr_traces = g_hash_table_size(ctx->session->ctf_traces);
+
        ret = check_traces_metadata(ctx);
        if (ret < 0) {
                goto end;
@@ -1645,6 +1654,15 @@ int add_traces(struct lttng_live_ctx *ctx)
                if (ret < 0) {
                        goto end;
                }
+               /*
+                * If a new trace got added while we were adding the trace, the
+                * iterator is invalid and we have to restart.
+                */
+               if (g_hash_table_size(ctx->session->ctf_traces) != nr_traces) {
+                       printf_verbose("New trace(s) added during add_one_trace()\n");
+                       printf_verbose("JORAJ: GREP HERE\n");
+                       goto retry;
+               }
        }
 
        ret = 0;