From cb0369458c84a18946db78af09d403a43d5df26e Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@efficios.com>
Date: Wed, 14 Feb 2024 11:09:27 -0500
Subject: [PATCH] cpp-common/bt2: add C++ component class bindings

Add C++ bindings for component classes.

Similar to how C++ bindings for components work, the
`CommonComponentClass` type is implicitly constructible from the
specialized component class types, so that it's possible to pass a
`SourceComponentClass` to something expecting a `ComponentClass`, for
instance.

Get a component class' name, description or help with the methods of the
same name.

Change-Id: Ia6301f4b37f4f86036f6e09cc2aaf49d7028c6fc
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/11803
---
 src/Makefile.am                        |   1 +
 src/cpp-common/bt2/component-class.hpp | 446 +++++++++++++++++++++++++
 2 files changed, 447 insertions(+)
 create mode 100644 src/cpp-common/bt2/component-class.hpp

diff --git a/src/Makefile.am b/src/Makefile.am
index 1a9ac61d..b226abee 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -118,6 +118,7 @@ cpp_common_libcpp_common_la_SOURCES = \
 	cpp-common/bt2/clock-class.hpp \
 	cpp-common/bt2/clock-snapshot.hpp \
 	cpp-common/bt2/component-class-dev.hpp \
+	cpp-common/bt2/component-class.hpp \
 	cpp-common/bt2/component-port.hpp \
 	cpp-common/bt2/exc.hpp \
 	cpp-common/bt2/field-class.hpp \
diff --git a/src/cpp-common/bt2/component-class.hpp b/src/cpp-common/bt2/component-class.hpp
new file mode 100644
index 00000000..51f7f470
--- /dev/null
+++ b/src/cpp-common/bt2/component-class.hpp
@@ -0,0 +1,446 @@
+/*
+ * Copyright (c) 2024 EfficiOS, Inc.
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#ifndef BABELTRACE_CPP_COMMON_BT2_COMPONENT_CLASS_HPP
+#define BABELTRACE_CPP_COMMON_BT2_COMPONENT_CLASS_HPP
+
+#include <babeltrace2/babeltrace.h>
+
+#include "cpp-common/bt2c/c-string-view.hpp"
+
+#include "borrowed-object.hpp"
+#include "shared-object.hpp"
+
+namespace bt2 {
+namespace internal {
+
+struct ComponentClassRefFuncs final
+{
+    static void get(const bt_component_class * const libObjPtr) noexcept
+    {
+        bt_component_class_get_ref(libObjPtr);
+    }
+
+    static void put(const bt_component_class * const libObjPtr) noexcept
+    {
+        bt_component_class_put_ref(libObjPtr);
+    }
+};
+
+} /* namespace internal */
+
+template <typename LibObjT>
+class CommonSourceComponentClass;
+
+template <typename LibObjT>
+class CommonFilterComponentClass;
+
+template <typename LibObjT>
+class CommonSinkComponentClass;
+
+template <typename LibObjT>
+class CommonComponentClass : public BorrowedObject<LibObjT>
+{
+private:
+    using _ThisBorrowedObject = BorrowedObject<LibObjT>;
+
+public:
+    using typename _ThisBorrowedObject::LibObjPtr;
+    using Shared = SharedObject<CommonComponentClass, LibObjT, internal::ComponentClassRefFuncs>;
+
+    explicit CommonComponentClass(const LibObjPtr libObjPtr) noexcept :
+        _ThisBorrowedObject {libObjPtr}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonComponentClass(const CommonComponentClass<OtherLibObjT> compCls) noexcept :
+        _ThisBorrowedObject {compCls}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonComponentClass operator=(const CommonComponentClass<OtherLibObjT> compCls) noexcept
+    {
+        _ThisBorrowedObject::operator=(compCls);
+        return *this;
+    }
+
+    /* Not `explicit` to make them behave like copy constructors */
+    CommonComponentClass(
+        const CommonSourceComponentClass<const bt_component_class_source> other) noexcept;
+    CommonComponentClass(
+        const CommonSourceComponentClass<bt_component_class_source> other) noexcept;
+    CommonComponentClass(
+        const CommonFilterComponentClass<const bt_component_class_filter> other) noexcept;
+    CommonComponentClass(
+        const CommonFilterComponentClass<bt_component_class_filter> other) noexcept;
+    CommonComponentClass(
+        const CommonSinkComponentClass<const bt_component_class_sink> other) noexcept;
+    CommonComponentClass(const CommonSinkComponentClass<bt_component_class_sink> other) noexcept;
+
+    CommonComponentClass
+    operator=(CommonSourceComponentClass<const bt_component_class_source> other) noexcept;
+    CommonComponentClass
+    operator=(CommonSourceComponentClass<bt_component_class_source> other) noexcept;
+    CommonComponentClass
+    operator=(CommonFilterComponentClass<const bt_component_class_filter> other) noexcept;
+    CommonComponentClass
+    operator=(CommonFilterComponentClass<bt_component_class_filter> other) noexcept;
+    CommonComponentClass
+    operator=(CommonSinkComponentClass<const bt_component_class_sink> other) noexcept;
+    CommonComponentClass
+    operator=(CommonSinkComponentClass<bt_component_class_sink> other) noexcept;
+
+    bool isSource() const noexcept
+    {
+        return static_cast<bool>(bt_component_class_is_source(this->libObjPtr()));
+    }
+
+    bool isFilter() const noexcept
+    {
+        return static_cast<bool>(bt_component_class_is_filter(this->libObjPtr()));
+    }
+
+    bool isSink() const noexcept
+    {
+        return static_cast<bool>(bt_component_class_is_sink(this->libObjPtr()));
+    }
+
+    bt2c::CStringView name() const noexcept
+    {
+        return bt_component_class_get_name(this->libObjPtr());
+    }
+
+    bt2c::CStringView description() const noexcept
+    {
+        return bt_component_class_get_description(this->libObjPtr());
+    }
+
+    bt2c::CStringView help() const noexcept
+    {
+        return bt_component_class_get_help(this->libObjPtr());
+    }
+};
+
+using ComponentClass = CommonComponentClass<bt_component_class>;
+using ConstComponentClass = CommonComponentClass<const bt_component_class>;
+
+namespace internal {
+
+struct SourceComponentClassRefFuncs final
+{
+    static void get(const bt_component_class_source * const libObjPtr) noexcept
+    {
+        bt_component_class_source_get_ref(libObjPtr);
+    }
+
+    static void put(const bt_component_class_source * const libObjPtr) noexcept
+    {
+        bt_component_class_source_put_ref(libObjPtr);
+    }
+};
+
+} /* namespace internal */
+
+template <typename LibObjT>
+class CommonSourceComponentClass final : public BorrowedObject<LibObjT>
+{
+private:
+    using _ThisBorrowedObject = BorrowedObject<LibObjT>;
+
+public:
+    using typename _ThisBorrowedObject::LibObjPtr;
+    using Shared =
+        SharedObject<CommonSourceComponentClass, LibObjT, internal::SourceComponentClassRefFuncs>;
+
+    CommonSourceComponentClass(const LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonSourceComponentClass(const CommonSourceComponentClass<OtherLibObjT> compCls) noexcept :
+        _ThisBorrowedObject {compCls}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonSourceComponentClass
+    operator=(const CommonSourceComponentClass<OtherLibObjT> compCls) noexcept
+    {
+        _ThisBorrowedObject::operator=(compCls);
+        return *this;
+    }
+
+    bt2c::CStringView name() const noexcept
+    {
+        return this->_constComponentClass().name();
+    }
+
+    bt2c::CStringView description() const noexcept
+    {
+        return this->_constComponentClass().description();
+    }
+
+    bt2c::CStringView help() const noexcept
+    {
+        return this->_constComponentClass().help();
+    }
+
+private:
+    ConstComponentClass _constComponentClass() const noexcept
+    {
+        return ConstComponentClass {
+            bt_component_class_source_as_component_class_const(this->libObjPtr())};
+    }
+};
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT>::CommonComponentClass(
+    const CommonSourceComponentClass<const bt_component_class_source> other) noexcept :
+    _ThisBorrowedObject {bt_component_class_source_as_component_class_const(other.libObjPtr())}
+{
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT>::CommonComponentClass(
+    const CommonSourceComponentClass<bt_component_class_source> other) noexcept :
+    _ThisBorrowedObject {bt_component_class_source_as_component_class(other.libObjPtr())}
+{
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT> CommonComponentClass<LibObjT>::operator=(
+    const CommonSourceComponentClass<const bt_component_class_source> other) noexcept
+{
+    BorrowedObject<LibObjT>::operator=(ConstComponentClass {
+        bt_component_class_source_as_component_class_const(other.libObjPtr())});
+    return *this;
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT> CommonComponentClass<LibObjT>::operator=(
+    const CommonSourceComponentClass<bt_component_class_source> other) noexcept
+{
+    BorrowedObject<LibObjT>::operator=(
+        ComponentClass {bt_component_class_source_as_component_class(other.libObjPtr())});
+    return *this;
+}
+
+using SourceComponentClass = CommonSourceComponentClass<bt_component_class_source>;
+using ConstSourceComponentClass = CommonSourceComponentClass<const bt_component_class_source>;
+
+namespace internal {
+
+struct FilterComponentClassRefFuncs final
+{
+    static void get(const bt_component_class_filter * const libObjPtr) noexcept
+    {
+        bt_component_class_filter_get_ref(libObjPtr);
+    }
+
+    static void put(const bt_component_class_filter * const libObjPtr) noexcept
+    {
+        bt_component_class_filter_put_ref(libObjPtr);
+    }
+};
+
+} /* namespace internal */
+
+template <typename LibObjT>
+class CommonFilterComponentClass final : public BorrowedObject<LibObjT>
+{
+private:
+    using _ThisBorrowedObject = BorrowedObject<LibObjT>;
+
+public:
+    using typename _ThisBorrowedObject::LibObjPtr;
+    using Shared =
+        SharedObject<CommonFilterComponentClass, LibObjT, internal::FilterComponentClassRefFuncs>;
+
+    CommonFilterComponentClass(const LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonFilterComponentClass(const CommonFilterComponentClass<OtherLibObjT> compCls) noexcept :
+        _ThisBorrowedObject {compCls}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonFilterComponentClass
+    operator=(const CommonFilterComponentClass<OtherLibObjT> compCls) noexcept
+    {
+        _ThisBorrowedObject::operator=(compCls);
+        return *this;
+    }
+
+    bt2c::CStringView name() const noexcept
+    {
+        return this->_constComponentClass().name();
+    }
+
+    bt2c::CStringView description() const noexcept
+    {
+        return this->_constComponentClass().description();
+    }
+
+    bt2c::CStringView help() const noexcept
+    {
+        return this->_constComponentClass().help();
+    }
+
+private:
+    ConstComponentClass _constComponentClass() const noexcept
+    {
+        return ConstComponentClass {
+            bt_component_class_filter_as_component_class_const(this->libObjPtr())};
+    }
+};
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT>::CommonComponentClass(
+    const CommonFilterComponentClass<const bt_component_class_filter> other) noexcept :
+    _ThisBorrowedObject {bt_component_class_filter_as_component_class_const(other.libObjPtr())}
+{
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT>::CommonComponentClass(
+    const CommonFilterComponentClass<bt_component_class_filter> other) noexcept :
+    _ThisBorrowedObject {bt_component_class_filter_as_component_class(other.libObjPtr())}
+{
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT> CommonComponentClass<LibObjT>::operator=(
+    const CommonFilterComponentClass<const bt_component_class_filter> other) noexcept
+{
+    BorrowedObject<LibObjT>::operator=(ConstComponentClass {
+        bt_component_class_filter_as_component_class_const(other.libObjPtr())});
+    return *this;
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT> CommonComponentClass<LibObjT>::operator=(
+    const CommonFilterComponentClass<bt_component_class_filter> other) noexcept
+{
+    BorrowedObject<LibObjT>::operator=(
+        ComponentClass {bt_component_class_filter_as_component_class(other.libObjPtr())});
+    return *this;
+}
+
+using FilterComponentClass = CommonFilterComponentClass<bt_component_class_filter>;
+using ConstFilterComponentClass = CommonFilterComponentClass<const bt_component_class_filter>;
+
+namespace internal {
+
+struct SinkComponentClassRefFuncs final
+{
+    static void get(const bt_component_class_sink * const libObjPtr) noexcept
+    {
+        bt_component_class_sink_get_ref(libObjPtr);
+    }
+
+    static void put(const bt_component_class_sink * const libObjPtr) noexcept
+    {
+        bt_component_class_sink_put_ref(libObjPtr);
+    }
+};
+
+} /* namespace internal */
+
+template <typename LibObjT>
+class CommonSinkComponentClass final : public BorrowedObject<LibObjT>
+{
+private:
+    using _ThisBorrowedObject = BorrowedObject<LibObjT>;
+
+public:
+    using typename _ThisBorrowedObject::LibObjPtr;
+    using Shared =
+        SharedObject<CommonSinkComponentClass, LibObjT, internal::SinkComponentClassRefFuncs>;
+
+    CommonSinkComponentClass(const LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonSinkComponentClass(const CommonSinkComponentClass<OtherLibObjT> compCls) noexcept :
+        _ThisBorrowedObject {compCls}
+    {
+    }
+
+    template <typename OtherLibObjT>
+    CommonSinkComponentClass
+    operator=(const CommonSinkComponentClass<OtherLibObjT> compCls) noexcept
+    {
+        _ThisBorrowedObject::operator=(compCls);
+        return *this;
+    }
+
+    bt2c::CStringView name() const noexcept
+    {
+        return this->_constComponentClass().name();
+    }
+
+    bt2c::CStringView description() const noexcept
+    {
+        return this->_constComponentClass().description();
+    }
+
+    bt2c::CStringView help() const noexcept
+    {
+        return this->_constComponentClass().help();
+    }
+
+private:
+    ConstComponentClass _constComponentClass() const noexcept
+    {
+        return ConstComponentClass {
+            bt_component_class_sink_as_component_class_const(this->libObjPtr())};
+    }
+};
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT>::CommonComponentClass(
+    const CommonSinkComponentClass<const bt_component_class_sink> other) noexcept :
+    _ThisBorrowedObject {bt_component_class_sink_as_component_class_const(other.libObjPtr())}
+{
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT>::CommonComponentClass(
+    const CommonSinkComponentClass<bt_component_class_sink> other) noexcept :
+    _ThisBorrowedObject {bt_component_class_sink_as_component_class(other.libObjPtr())}
+{
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT> CommonComponentClass<LibObjT>::operator=(
+    const CommonSinkComponentClass<const bt_component_class_sink> other) noexcept
+{
+    BorrowedObject<LibObjT>::operator=(
+        ConstComponentClass {bt_component_class_sink_as_component_class_const(other.libObjPtr())});
+    return *this;
+}
+
+template <typename LibObjT>
+CommonComponentClass<LibObjT> CommonComponentClass<LibObjT>::operator=(
+    const CommonSinkComponentClass<bt_component_class_sink> other) noexcept
+{
+    BorrowedObject<LibObjT>::operator=(
+        ComponentClass {bt_component_class_sink_as_component_class(other.libObjPtr())});
+    return *this;
+}
+
+using SinkComponentClass = CommonSinkComponentClass<bt_component_class_sink>;
+using ConstSinkComponentClass = CommonSinkComponentClass<const bt_component_class_sink>;
+
+} /* namespace bt2 */
+
+#endif /* BABELTRACE_CPP_COMMON_BT2_COMPONENT_CLASS_HPP */
-- 
2.34.1