sessiond: generate packet header, packet context and event header dynamically

[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.cpp

diff --git a/src/bin/lttng-sessiond/ust-app.cpp b/src/bin/lttng-sessiond/ust-app.cpp
index 88db75f8f4d7da8f1f2ae5cc3d7978cae26fafdd..3f39b02e4d9ee3d0e6faf65fa1d243ddf242f2e0 100644 (file)
--- a/src/bin/lttng-sessiond/ust-app.cpp
+++ b/src/bin/lttng-sessiond/ust-app.cpp
@@ -6426,23 +6426,47 @@ static int handle_app_register_channel_notification(int sock,
         * that all apps provide the same typing for the context fields as a
         * sanity check.
         */
-       lst::type::cuptr context_fields = lttng::make_unique<lst::structure_type>(0,
-                       lsu::create_trace_fields_from_ust_ctl_fields(*locked_registry_session,
-                                       ust_ctl_context_fields.get(), context_field_count));
+       try {
+               auto app_context_fields = lsu::create_trace_fields_from_ust_ctl_fields(
+                               *locked_registry_session, ust_ctl_context_fields.get(),
+                               context_field_count);
 
-       if (!ust_reg_chan.is_registered()) {
-               ust_reg_chan.set_context(std::move(context_fields));
-       } else {
-               /*
-                * Validate that the context fields match between
-                * registry and newcoming application.
-                */
-               if (ust_reg_chan.get_context() != *context_fields) {
-                       ERR("Registering application channel due to context field mismatch: pid = %d, sock = %d",
-                               app->pid, app->sock);
-                       ret_code = -EINVAL;
-                       goto reply;
+               if (!ust_reg_chan.is_registered()) {
+                       lst::type::cuptr event_context = app_context_fields.size() ?
+                                       lttng::make_unique<lst::structure_type>(
+                                                       0, std::move(app_context_fields)) :
+                                       nullptr;
+
+                       ust_reg_chan.set_event_context(std::move(event_context));
+               } else {
+                       /*
+                        * Validate that the context fields match between
+                        * registry and newcoming application.
+                        */
+                       bool context_fields_match;
+                       const auto *previous_event_context = ust_reg_chan.get_event_context();
+
+                       if (!previous_event_context) {
+                               context_fields_match = app_context_fields.size() == 0;
+                       } else {
+                               const lst::structure_type app_event_context_struct(
+                                               0, std::move(app_context_fields));
+
+                               context_fields_match = *previous_event_context ==
+                                               app_event_context_struct;
+                       }
+
+                       if (!context_fields_match) {
+                               ERR("Registering application channel due to context field mismatch: pid = %d, sock = %d",
+                                               app->pid, app->sock);
+                               ret_code = -EINVAL;
+                               goto reply;
+                       }
                }
+       } catch (std::exception& ex) {
+               ERR("Failed to handle application context: %s", ex.what());
+               ret_code = -EINVAL;
+               goto reply;
        }
 
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