Fix: don't update the trace collection if no new streams were received

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/formats/lttng-live/lttng-live-comm.c b/formats/lttng-live/lttng-live-comm.c
index 3aad981008bbe02022ecce743fb7de2e9c6ee2c9..5b7f058aabdf493f82dff238afad69fe8b19587e 100644 (file)
--- a/formats/lttng-live/lttng-live-comm.c
+++ b/formats/lttng-live/lttng-live-comm.c
@@ -532,18 +532,22 @@ error:
        return -1;
 }
 
+/*
+ * Ask the relay for new streams.
+ *
+ * Returns the number of new streams received or a negative value on error.
+ */
 static
 int ask_new_streams(struct lttng_live_ctx *ctx)
 {
-       int i, ret = 0;
+       int i, ret = 0, nb_streams = 0;
        uint64_t id;
 
 restart:
        for (i = 0; i < ctx->session_ids->len; i++) {
                id = g_array_index(ctx->session_ids, uint64_t, i);
                ret = lttng_live_get_new_streams(ctx, id);
-               printf_verbose("Asking for new streams returns %d\n",
-                               ret);
+               printf_verbose("Asking for new streams returns %d\n", ret);
                if (ret < 0) {
                        if (lttng_live_should_quit()) {
                                goto end;
@@ -566,8 +570,11 @@ restart:
                                ret = -1;
                                goto end;
                        }
+               } else {
+                       nb_streams += ret;
                }
        }
+       ret = nb_streams;
 
 end:
        return ret;
@@ -692,8 +699,9 @@ retry:
                        ret = ask_new_streams(ctx);
                        if (ret < 0)
                                goto error;
-                       g_hash_table_foreach(ctx->session->ctf_traces,
-                                       add_traces, ctx->bt_ctx);
+                       else if (ret > 0)
+                               g_hash_table_foreach(ctx->session->ctf_traces,
+                                               add_traces, ctx->bt_ctx);
                }
                if (rp.flags & (LTTNG_VIEWER_FLAG_NEW_METADATA
                                | LTTNG_VIEWER_FLAG_NEW_STREAM)) {
@@ -875,7 +883,7 @@ int get_new_metadata(struct lttng_live_ctx *ctx,
 {
        int ret = 0;
        struct lttng_live_viewer_stream *metadata_stream;
-       size_t size, len_read = 0;;
+       size_t size, len_read = 0;
 
        metadata_stream = viewer_stream->ctf_trace->metadata_stream;
        if (!metadata_stream) {
@@ -989,11 +997,13 @@ retry:
                                goto error;
                }
                if (rp.flags & LTTNG_VIEWER_FLAG_NEW_STREAM) {
+                       printf_verbose("get_next_index: need new streams\n");
                        ret = ask_new_streams(ctx);
                        if (ret < 0)
                                goto error;
-                       g_hash_table_foreach(ctx->session->ctf_traces,
-                                       add_traces, ctx->bt_ctx);
+                       else if (ret > 0)
+                               g_hash_table_foreach(ctx->session->ctf_traces,
+                                               add_traces, ctx->bt_ctx);
                }
                break;
        case LTTNG_VIEWER_INDEX_RETRY:
@@ -1316,13 +1326,17 @@ end:
        return;
 }
 
+/*
+ * Request new streams for a session.
+ * Returns the number of streams received or a negative value on error.
+ */
 int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
 {
        struct lttng_viewer_cmd cmd;
        struct lttng_viewer_new_streams_request rq;
        struct lttng_viewer_new_streams_response rp;
        struct lttng_viewer_stream stream;
-       int ret, i;
+       int ret, i, nb_streams = 0;
        ssize_t ret_len;
        uint32_t stream_count;
 
@@ -1427,9 +1441,10 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
                if (ret < 0) {
                        goto error;
                }
+               nb_streams++;
 
        }
-       ret = 0;
+       ret = nb_streams;
 end:
        return ret;