sessiond: ust: conditionally enable the underscore prefix variant quirk

[lttng-tools.git] / src / bin / lttng-sessiond / tsdl-trace-class-visitor.hpp

diff --git a/src/bin/lttng-sessiond/tsdl-trace-class-visitor.hpp b/src/bin/lttng-sessiond/tsdl-trace-class-visitor.hpp
index d06ea9983afd4871d306fde9f56ed92e7670f48f..1b8bd642de9b885614972a19250da54824b05e2b 100644 (file)
--- a/src/bin/lttng-sessiond/tsdl-trace-class-visitor.hpp
+++ b/src/bin/lttng-sessiond/tsdl-trace-class-visitor.hpp
@@ -15,6 +15,7 @@
 #include <vendor/optional.hpp>
 
 #include <functional>
+#include <unordered_map>
 
 namespace lttng {
 namespace sessiond {
@@ -22,6 +23,36 @@ namespace tsdl {
 
 using append_metadata_fragment_function = std::function<void(const std::string& fragment)>;
 
+namespace details {
+/*
+ * Register types to be overriden. For example, a TSDL-safe copy of a type can
+ * be added to be overriden whenever the original type is encountered.
+ *
+ * Note that this class assumes no ownership of the original types. It assumes
+ * that the original types live as long as the original trace.
+ */
+class type_overrider {
+public:
+       type_overrider() = default;
+
+       void publish(const lttng::sessiond::trace::type& original,
+                       lttng::sessiond::trace::type::cuptr new_type_override);
+       const lttng::sessiond::trace::type& type(
+                       const lttng::sessiond::trace::type& original) const noexcept;
+
+private:
+       std::unordered_map<const lttng::sessiond::trace::type *, lttng::sessiond::trace::type::cuptr>
+                       _overriden_types;
+};
+} /* namespace details. */
+
+/*
+ * TSDL-producing trace class visitor.
+ *
+ * An instance of this class must not be used on multiple trace class instances.
+ * The `append_metadata` callback is automatically invoked when a coherent
+ * fragment of TSDL is available.
+ */
 class trace_class_visitor : public lttng::sessiond::trace::trace_class_visitor {
 public:
        trace_class_visitor(const lttng::sessiond::trace::abi& trace_abi,
@@ -35,9 +66,30 @@ public:
 private:
        /* Coherent (parseable) fragments must be appended. */
        void append_metadata_fragment(const std::string& fragment) const;
+       const lttng::sessiond::trace::type& _lookup_field_type(
+                       const lttng::sessiond::trace::field_location& field_location) const;
 
        const lttng::sessiond::trace::abi& _trace_abi;
        const append_metadata_fragment_function _append_metadata_fragment;
+       details::type_overrider _sanitized_types_overrides;
+
+       /*
+        * Current visit context.
+        *
+        * The members of a trace class hierarchy do not provide back-references
+        * up the hierarchy (e.g. stream class to its parent trace class).
+        *
+        * This context allows the visitor to evaluate a "field location".
+        *
+        * _current_trace_class is set the first time a trace class is visited and
+        * remains valid until the destruction of this object.
+        *
+        * _current_stream_class and _current_event_class are set only in the
+        * context of the visit of a stream class and of its event class(es).
+        */
+       const lttng::sessiond::trace::trace_class *_current_trace_class = nullptr;
+       const lttng::sessiond::trace::stream_class *_current_stream_class = nullptr;
+       const lttng::sessiond::trace::event_class *_current_event_class = nullptr;
 };
 
 } /* namespace tsdl */