Clean-up: modernize pretty_xml.cpp

[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 6d629e2beff51dbe35268ca8b8f4721bf7e4031b..c15ee8f4586c24250219c1c7ffddcf48d7587e4c 100644 (file)
--- a/src/bin/lttng-sessiond/tsdl-trace-class-visitor.hpp
+++ b/src/bin/lttng-sessiond/tsdl-trace-class-visitor.hpp
@@ -8,13 +8,14 @@
 #ifndef LTTNG_TSDL_TRACE_CLASS_VISITOR_H
 #define LTTNG_TSDL_TRACE_CLASS_VISITOR_H
 
-#include "trace-class.hpp"
-#include "stream-class.hpp"
 #include "event-class.hpp"
+#include "stream-class.hpp"
+#include "trace-class.hpp"
 
 #include <vendor/optional.hpp>
 
 #include <functional>
+#include <unordered_map>
 
 namespace lttng {
 namespace sessiond {
@@ -22,36 +23,73 @@ namespace tsdl {
 
 using append_metadata_fragment_function = std::function<void(const std::string& fragment)>;
 
-class trace_class_visitor : public lttng::sessiond::trace::trace_class_visitor {
+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:
-       trace_class_visitor(const lttng::sessiond::trace::abi& trace_abi,
-                       append_metadata_fragment_function append_metadata);
+       type_overrider() = default;
 
-       /* trace class visitor interface. */
-       virtual void visit(const lttng::sessiond::trace::trace_class& trace_class) override final;
+       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;
 
-       /* clock class visitor interface. */
-       virtual void visit(const lttng::sessiond::trace::clock_class& clock_class) override final;
-
-       /* environment visitor interface. */
-       virtual void environment_begin() override final;
-       virtual void visit(const lttng::sessiond::trace::environment_field<int64_t>& field) override final;
-       virtual void visit(const lttng::sessiond::trace::environment_field<const char *>& field) override final;
-       virtual void environment_end() override final;
+private:
+       std::unordered_map<const lttng::sessiond::trace::type *, lttng::sessiond::trace::type::cuptr>
+               _overriden_types;
+};
+} /* namespace details. */
 
-       /* stream class visitor interface. */
-       virtual void visit(const lttng::sessiond::trace::stream_class& stream_class) override final;
+/*
+ * 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,
+                           append_metadata_fragment_function append_metadata);
 
-       /* event class visitor interface. */
-       virtual void visit(const lttng::sessiond::trace::event_class& event_class) override final;
+       void visit(const lttng::sessiond::trace::trace_class& trace_class) final;
+       void visit(const lttng::sessiond::trace::clock_class& clock_class) final;
+       void visit(const lttng::sessiond::trace::stream_class& stream_class) final;
+       void visit(const lttng::sessiond::trace::event_class& event_class) final;
 
 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;
-       std::string _environment;
+       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 */