src/bin/lttng-sessiond/trace-class.hpp

   1 /*
   2  * Copyright (C) 2022 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-only
   5  *
   6  */
   7
   8 #ifndef LTTNG_TRACE_CLASS_H
   9 #define LTTNG_TRACE_CLASS_H
  10
  11 #include "field.hpp"
  12
  13 #include <common/uuid.hpp>
  14
  15 namespace lttng {
  16 namespace sessiond {
  17 namespace trace {
  18
  19 class clock_class;
  20 class stream_class;
  21 class event_class;
  22 class trace_class_visitor;
  23 class trace_class_environment_visitor;
  24
  25 struct abi {
  26         unsigned int bits_per_long;
  27         unsigned int long_alignment;
  28         unsigned int uint8_t_alignment;
  29         unsigned int uint16_t_alignment;
  30         unsigned int uint32_t_alignment;
  31         unsigned int uint64_t_alignment;
  32         enum byte_order byte_order;
  33 };
  34
  35 template <class ValueType>
  36 class environment_field {
  37 public:
  38         environment_field(const char *in_name, const ValueType& in_value) :
  39                 name(in_name), value(in_value)
  40         {
  41         }
  42
  43         const char* const name;
  44         const ValueType& value;
  45 };
  46
  47 class trace_class {
  48 public:
  49         virtual ~trace_class() = default;
  50         trace_class(const trace_class&) = delete;
  51         trace_class(trace_class&&) = delete;
  52         trace_class& operator=(trace_class&&) = delete;
  53         trace_class& operator=(const trace_class&) = delete;
  54
  55         /*
  56          * Derived classes must implement the _accept_on_*()
  57          * to continue the traversal to the trace class' children.
  58          */
  59         virtual void accept(trace_class_visitor& trace_class_visitor) const;
  60         virtual void accept(trace_class_environment_visitor& environment_visitor) const = 0;
  61         virtual const lttng::sessiond::trace::type *packet_header() const noexcept = 0;
  62
  63         const struct abi abi;
  64         const lttng_uuid uuid;
  65
  66 protected:
  67         trace_class(const struct abi& abi, const lttng_uuid& trace_uuid);
  68         virtual void _accept_on_clock_classes(trace_class_visitor& trace_class_visitor) const = 0;
  69         virtual void _accept_on_stream_classes(trace_class_visitor& trace_class_visitor) const = 0;
  70 };
  71
  72 class trace_class_environment_visitor {
  73 public:
  74         trace_class_environment_visitor() = default;
  75         virtual ~trace_class_environment_visitor() = default;
  76         trace_class_environment_visitor(const trace_class_environment_visitor&) = delete;
  77         trace_class_environment_visitor(trace_class_environment_visitor&&) = delete;
  78         trace_class_environment_visitor& operator=(trace_class_environment_visitor&&) = delete;
  79         trace_class_environment_visitor& operator=(const trace_class_environment_visitor&) = delete;
  80
  81         virtual void visit(const environment_field<int64_t>& field) = 0;
  82         virtual void visit(const environment_field<const char *>& field) = 0;
  83         virtual void visit(const environment_field<std::string>& field);
  84 };
  85
  86 class trace_class_visitor {
  87 public:
  88         using cuptr = std::unique_ptr<trace_class_visitor>;
  89
  90         trace_class_visitor() = default;
  91         virtual ~trace_class_visitor() = default;
  92         trace_class_visitor(const trace_class_visitor&) = delete;
  93         trace_class_visitor(trace_class_visitor&&) = delete;
  94         trace_class_visitor& operator=(trace_class_visitor&&) = delete;
  95         trace_class_visitor& operator=(const trace_class_visitor&) = delete;
  96
  97         virtual void visit(const lttng::sessiond::trace::trace_class& trace_class) = 0;
  98         virtual void visit(const lttng::sessiond::trace::clock_class& clock_class) = 0;
  99         virtual void visit(const lttng::sessiond::trace::stream_class& stream_class) = 0;
 100         virtual void visit(const lttng::sessiond::trace::event_class& event_class) = 0;
 101 };
 102
 103 } /* namespace trace */
 104 } /* namespace sessiond */
 105 } /* namespace lttng */
 106
 107 #endif /* LTTNG_TRACE_CLASS_H */