[babeltrace.git] / src / cpp-common / bt2 / component-class-dev.hpp

/*
 * Copyright (c) 2024 EfficiOS, Inc.
 *
 * SPDX-License-Identifier: MIT
 */

#ifndef BABELTRACE_CPP_COMMON_BT2_COMPONENT_CLASS_DEV_HPP
#define BABELTRACE_CPP_COMMON_BT2_COMPONENT_CLASS_DEV_HPP

#include <cstdint>

#include <glib.h>

#include "cpp-common/bt2c/c-string-view.hpp"
#include "cpp-common/bt2c/logging.hpp"
#include "cpp-common/vendor/fmt/core.h"

#include "exc.hpp"
#include "internal/comp-cls-bridge.hpp"
#include "private-query-executor.hpp"
#include "self-component-port.hpp"

namespace bt2 {

template <typename UserMessageIteratorT, typename UserComponentT>
class UserMessageIterator;

/*
 * Base class of any user component.
 *
 * See the specific `bt2::UserSourceComponent`,
 * `bt2::UserFilterComponent`, and `bt2::UserSinkComponent`.
 */
template <typename SelfCompT, typename InitDataT, typename QueryDataT>
class UserComponent
{
    /* Give a related message iterator access to this logger */
    template <typename, typename>
    friend class UserMessageIterator;

public:
    using InitData = InitDataT;
    using QueryData = QueryDataT;

    static constexpr auto description = nullptr;
    static constexpr auto help = nullptr;

protected:
    explicit UserComponent(const SelfCompT selfComp, const std::string& logTag) :
        _mLogger {selfComp, fmt::format("{}/[{}]", logTag, selfComp.name())}, _mSelfComp {selfComp}
    {
    }

    bt2c::CStringView _name() const noexcept
    {
        return _mSelfComp.name();
    }

    LoggingLevel _loggingLevel() const noexcept
    {
        return _mSelfComp.loggingLevel();
    }

    std::uint64_t _graphMipVersion() const noexcept
    {
        return _mSelfComp.graphMipVersion();
    }

    SelfCompT _selfComp() noexcept
    {
        return _mSelfComp;
    }

    bt2c::Logger _mLogger;

private:
    SelfCompT _mSelfComp;
};

/*
 * Base class of a user source component `UserComponentT` (CRTP).
 *
 * `UserComponentT` must define a static member `name` of type
 * `const char *` to provide the name of the component class.
 *
 * `UserComponentT` may define the static members `description` and/or
 * `help` of type `const char *` to provide the description and/or help
 * of the component class.
 *
 * UserComponentT::UserComponentT() must accept, in this order:
 *
 *  1. A `bt2::SelfSourceComponent` parameter, which it needs to forward
 *     to bt2::UserSourceComponent::UserSourceComponent().
 *
 *  2. A `bt2::ConstValue` parameter (the initialization parameters).
 *
 *  3. An `InitDataT *` parameter (the initialization method data).
 *
 * `UserMessageIteratorT`, the message iterator class to use, must inherit
 * `UserMessageIterator`.
 *
 * UserComponentT::_query() receives a query method data pointer of type
 * `QueryDataT *` as its last parameter.
 */
template <typename UserComponentT, typename UserMessageIteratorT, typename InitDataT = void,
          typename QueryDataT = void>
class UserSourceComponent : public UserComponent<SelfSourceComponent, InitDataT, QueryDataT>
{
    static_assert(std::is_base_of<UserMessageIterator<UserMessageIteratorT, UserComponentT>,
                                  UserMessageIteratorT>::value,
                  "`UserMessageIteratorT` inherits `UserMessageIterator`");

public:
    using MessageIterator = UserMessageIteratorT;

protected:
    using _OutputPorts = SelfSourceComponent::OutputPorts;

    explicit UserSourceComponent(const SelfSourceComponent selfComp, const std::string& logTag) :
        UserComponent<SelfSourceComponent, InitDataT, QueryDataT> {selfComp, logTag}
    {
    }

public:
    static Value::Shared query(const SelfComponentClass selfCompCls,
                               const PrivateQueryExecutor privQueryExec,
                               const bt2c::CStringView obj, const ConstValue params,
                               QueryDataT * const data)
    {
        return UserComponentT::_query(selfCompCls, privQueryExec, obj, params, data);
    }

    static void getSupportedMipVersions(const SelfComponentClass selfCompCls,
                                        const ConstValue params, const LoggingLevel loggingLevel,
                                        const UnsignedIntegerRangeSet ranges)
    {
        UserComponentT::_getSupportedMipVersions(selfCompCls, params, loggingLevel, ranges);
    }

    void outputPortConnected(const SelfComponentOutputPort outputPort,
                             const ConstInputPort inputPort)
    {
        static_cast<UserComponentT&>(*this)._outputPortConnected(outputPort, inputPort);
    }

protected:
    /* Overloadable */
    static Value::Shared _query(SelfComponentClass, PrivateQueryExecutor, bt2c::CStringView,
                                ConstValue, QueryDataT *)
    {
        throw UnknownObject {};
    }

    /* Overloadable */
    static void _getSupportedMipVersions(SelfComponentClass, ConstValue, LoggingLevel,
                                         const UnsignedIntegerRangeSet ranges)
    {
        ranges.addRange(0, 0);
    }

    /* Overloadable */
    void _outputPortConnected(SelfComponentOutputPort, ConstInputPort)
    {
    }

    template <typename DataT>
    _OutputPorts::Port _addOutputPort(const bt2c::CStringView name, DataT& data)
    {
        return this->_selfComp().addOutputPort(name, data);
    }

    _OutputPorts::Port _addOutputPort(const bt2c::CStringView name)
    {
        return this->_selfComp().addOutputPort(name);
    }

    _OutputPorts _outputPorts() noexcept
    {
        return this->_selfComp().outputPorts();
    }
};

/*
 * Base class of a user filter component `UserComponentT` (CRTP).
 *
 * `UserComponentT` must define a static member `name` of type
 * `const char *` to provide the name of the component class.
 *
 * `UserComponentT` may define the static members `description` and/or
 * `help` of type `const char *` to provide the description and/or help
 * of the component class.
 *
 * UserComponentT::UserComponentT() must accept, in this order:
 *
 *  1. A `bt2::SelfFilterComponent` parameter, which it needs to forward
 *     to bt2::UserFilterComponent::UserFilterComponent().
 *
 *  2. A `bt2::ConstValue` parameter (the initialization parameters).
 *
 *  3. An `InitDataT *` parameter (the initialization method data).
 *
 * `UserMessageIteratorT`, the message iterator class to use, must inherit
 * `UserMessageIterator`.
 *
 * UserComponentT::_query() receives a query method data pointer of type
 * `QueryDataT *` as its last parameter.
 */
template <typename UserComponentT, typename UserMessageIteratorT, typename InitDataT = void,
          typename QueryDataT = void>
class UserFilterComponent : public UserComponent<SelfFilterComponent, InitDataT, QueryDataT>
{
    static_assert(std::is_base_of<UserMessageIterator<UserMessageIteratorT, UserComponentT>,
                                  UserMessageIteratorT>::value,
                  "`UserMessageIteratorT` inherits `UserMessageIterator`");

public:
    using MessageIterator = UserMessageIteratorT;

protected:
    using _InputPorts = SelfFilterComponent::InputPorts;
    using _OutputPorts = SelfFilterComponent::OutputPorts;

    explicit UserFilterComponent(const SelfFilterComponent selfComp, const std::string& logTag) :
        UserComponent<SelfFilterComponent, InitDataT, QueryDataT> {selfComp, logTag}
    {
    }

public:
    static Value::Shared query(const SelfComponentClass selfCompCls,
                               const PrivateQueryExecutor privQueryExec,
                               const bt2c::CStringView obj, const ConstValue params,
                               QueryDataT * const data)
    {
        return UserComponentT::_query(selfCompCls, privQueryExec, obj, params, data);
    }

    static void getSupportedMipVersions(const SelfComponentClass selfCompCls,
                                        const ConstValue params, const LoggingLevel loggingLevel,
                                        const UnsignedIntegerRangeSet ranges)
    {
        UserComponentT::_getSupportedMipVersions(selfCompCls, params, loggingLevel, ranges);
    }

    void inputPortConnected(const SelfComponentInputPort inputPort,
                            const ConstOutputPort outputPort)
    {
        static_cast<UserComponentT&>(*this)._inputPortConnected(inputPort, outputPort);
    }

    void outputPortConnected(const SelfComponentOutputPort outputPort,
                             const ConstInputPort inputPort)
    {
        static_cast<UserComponentT&>(*this)._outputPortConnected(outputPort, inputPort);
    }

protected:
    /* Overloadable */
    static Value::Shared _query(SelfComponentClass, PrivateQueryExecutor, bt2c::CStringView,
                                ConstValue, QueryDataT *)
    {
        throw UnknownObject {};
    }

    /* Overloadable */
    static void _getSupportedMipVersions(SelfComponentClass, ConstValue, LoggingLevel,
                                         const UnsignedIntegerRangeSet ranges)
    {
        ranges.addRange(0, 0);
    }

    /* Overloadable */
    void _inputPortConnected(SelfComponentInputPort, ConstOutputPort)
    {
    }

    /* Overloadable */
    void _outputPortConnected(SelfComponentOutputPort, ConstInputPort)
    {
    }

    template <typename DataT>
    _OutputPorts::Port _addInputPort(const bt2c::CStringView name, DataT& data)
    {
        return this->_selfComp().addInputPort(name, data);
    }

    _InputPorts::Port _addInputPort(const bt2c::CStringView name)
    {
        return this->_selfComp().addInputPort(name);
    }

    _InputPorts _inputPorts() noexcept
    {
        return this->_selfComp().inputPorts();
    }

    template <typename DataT>
    _OutputPorts::Port _addOutputPort(const bt2c::CStringView name, DataT& data)
    {
        return this->_selfComp().addOutputPort(name, data);
    }

    _OutputPorts::Port _addOutputPort(const bt2c::CStringView name)
    {
        return this->_selfComp().addOutputPort(name);
    }

    _OutputPorts _outputPorts() noexcept
    {
        return this->_selfComp().outputPorts();
    }
};

/*
 * Base class of a user sink component `UserComponentT` (CRTP).
 *
 * `UserComponentT` must define a static member `name` of type
 * `const char *` to provide the name of the component class.
 *
 * `UserComponentT` may define the static members `description` and/or
 * `help` of type `const char *` to provide the description and/or help
 * of the component class.
 *
 * UserComponentT::UserComponentT() must accept, in this order:
 *
 *  1. A `bt2::SelfSinkComponent` parameter, which it needs to forward
 *     to bt2::UserSinkComponent::UserSinkComponent().
 *
 *  2. A `bt2::ConstValue` parameter (the initialization parameters).
 *
 *  3. An `InitDataT *` parameter (the initialization method data).
 *
 * `UserComponentT` must implement:
 *
 *     bool _consume();
 *
 * This method returns `true` if the sink component still needs to
 * consume, or `false` if it's finished.
 *
 * UserComponentT::_query() receives a query method data pointer of type
 * `QueryDataT *` as its last parameter.

 */
template <typename UserComponentT, typename InitDataT = void, typename QueryDataT = void>
class UserSinkComponent : public UserComponent<SelfSinkComponent, InitDataT, QueryDataT>
{
protected:
    using _InputPorts = SelfSinkComponent::InputPorts;

    explicit UserSinkComponent(const SelfSinkComponent selfComp, const std::string& logTag) :
        UserComponent<SelfSinkComponent, InitDataT, QueryDataT> {selfComp, logTag}
    {
    }

public:
    static Value::Shared query(const SelfComponentClass selfCompCls,
                               const PrivateQueryExecutor privQueryExec,
                               const bt2c::CStringView obj, const ConstValue params,
                               QueryDataT * const data)
    {
        return UserComponentT::_query(selfCompCls, privQueryExec, obj, params, data);
    }

    static void getSupportedMipVersions(const SelfComponentClass selfCompCls,
                                        const ConstValue params, const LoggingLevel loggingLevel,
                                        const UnsignedIntegerRangeSet ranges)
    {
        UserComponentT::_getSupportedMipVersions(selfCompCls, params, loggingLevel, ranges);
    }

    void graphIsConfigured()
    {
        static_cast<UserComponentT&>(*this)._graphIsConfigured();
    }

    void inputPortConnected(const SelfComponentInputPort inputPort,
                            const ConstOutputPort outputPort)
    {
        static_cast<UserComponentT&>(*this)._inputPortConnected(inputPort, outputPort);
    }

    bool consume()
    {
        return static_cast<UserComponentT&>(*this)._consume();
    }

protected:
    /* Overloadable */
    static Value::Shared _query(SelfComponentClass, PrivateQueryExecutor, bt2c::CStringView,
                                ConstValue, QueryDataT *)
    {
        throw UnknownObject {};
    }

    /* Overloadable */
    static void _getSupportedMipVersions(SelfComponentClass, ConstValue, LoggingLevel,
                                         const UnsignedIntegerRangeSet ranges)
    {
        ranges.addRange(0, 0);
    }

    /* Overloadable */
    void _graphIsConfigured()
    {
    }

    /* Overloadable */
    void _inputPortConnected(SelfComponentInputPort, ConstOutputPort)
    {
    }

    MessageIterator::Shared _createMessageIterator(const _InputPorts::Port port)
    {
        return this->_selfComp().createMessageIterator(port);
    }

    template <typename DataT>
    _InputPorts::Port _addInputPort(const bt2c::CStringView name, DataT& data)
    {
        return this->_selfComp().addInputPort(name, data);
    }

    _InputPorts::Port _addInputPort(const bt2c::CStringView name)
    {
        return this->_selfComp().addInputPort(name);
    }

    _InputPorts _inputPorts() noexcept
    {
        return this->_selfComp().inputPorts();
    }
};

/*
 * Base class of a user message iterator `UserMessageIteratorT` (CRTP)
 * of which the parent user component class is `UserComponentT`.
 *
 * `UserMessageIteratorT::UserMessageIteratorT()` must accept a
 * `bt2::SelfMessageIterator` parameter, which it needs to forward to
 * bt2::UserMessageIterator::UserMessageIterator().
 *
 * The public next() method below (called by the bridge) implements the
 * very common pattern of appending messages into the output array, and,
 * meanwhile:
 *
 * If it catches a `bt2::TryAgain` exception:
 *     If the message array isn't empty, transform this into a success
 *     (don't throw).
 *
 *     Otherwise rethrow.
 *
 * If it catches an error:
 *     If the message array isn't empty, transform this into a success
 *     (don't throw), but save the error of the current thread and the
 *     type of error to throw the next time the user calls next().
 *
 *     Otherwise rethrow.
 *
 * `UserMessageIteratorT` must implement:
 *
 *     void _next(bt2::ConstMessageArray& messages);
 *
 * This method fills `messages` with at most `messages.capacity()`
 * messages and may throw `bt2::TryAgain` or a valid error whenever.
 * Leaving an empty `messages` means the end of iteration.
 */
template <typename UserMessageIteratorT, typename UserComponentT>
class UserMessageIterator
{
private:
    /* Type of `_mExcToThrowType` */
    enum class _ExcToThrowType
    {
        NONE,
        ERROR,
        MEM_ERROR,
    };

protected:
    explicit UserMessageIterator(const SelfMessageIterator selfMsgIter,
                                 const std::string& logTagSuffix) :
        _mSelfMsgIter {selfMsgIter},
        _mLogger {selfMsgIter,
                  fmt::format("{}/{}", this->_component()._mLogger.tag(), logTagSuffix)}
    {
    }

public:
    void next(bt2::ConstMessageArray& messages)
    {
        /* Any saved error? Now is the time to throw */
        if (G_UNLIKELY(_mExcToThrowType != _ExcToThrowType::NONE)) {
            /* Move `_mSavedLibError`, if any, as current thread error */
            if (_mSavedLibError) {
                bt_current_thread_move_error(_mSavedLibError.release());
            }

            /* Throw the corresponding exception */
            if (_mExcToThrowType == _ExcToThrowType::ERROR) {
                throw bt2::Error {};
            } else {
                BT_ASSERT(_mExcToThrowType == _ExcToThrowType::MEM_ERROR);
                throw bt2::MemoryError {};
            }
        }

        /*
         * When catching some exception below, if our message array
         * isn't empty, then return immediately before throwing to
         * provide those messages to downstream.
         *
         * When catching an error, also save the current thread error,
         * if any, so that we can restore it later (see the beginning of
         * this method).
         */
        BT_ASSERT_DBG(_mExcToThrowType == _ExcToThrowType::NONE);

        try {
            this->_userObj()._next(messages);

            /* We're done: everything below is exception handling */
            return;
        } catch (const bt2::TryAgain&) {
            if (messages.isEmpty()) {
                throw;
            }
        } catch (const std::bad_alloc&) {
            if (messages.isEmpty()) {
                throw;
            }

            _mExcToThrowType = _ExcToThrowType::MEM_ERROR;
        } catch (const bt2::Error&) {
            if (messages.isEmpty()) {
                throw;
            }

            _mExcToThrowType = _ExcToThrowType::ERROR;
        }

        if (_mExcToThrowType != _ExcToThrowType::NONE) {
            BT_CPPLOGE(
                "An error occurred, but there are {} messages to return: delaying the error reporting.",
                messages.length());
            BT_ASSERT(!_mSavedLibError);
            _mSavedLibError.reset(bt_current_thread_take_error());
        }
    }

    bool canSeekBeginning()
    {
        this->_resetError();
        return this->_userObj()._canSeekBeginning();
    }

    void seekBeginning()
    {
        this->_resetError();
        return this->_userObj()._seekBeginning();
    }

    bool canSeekNsFromOrigin(const std::int64_t nsFromOrigin)
    {
        this->_resetError();
        return this->_userObj()._canSeekNsFromOrigin(nsFromOrigin);
    }

    void seekNsFromOrigin(const std::int64_t nsFromOrigin)
    {
        this->_resetError();
        this->_userObj()._seekNsFromOrigin(nsFromOrigin);
    }

protected:
    /* Overloadable */
    bool _canSeekBeginning() noexcept
    {
        return false;
    }

    /* Overloadable */
    void _seekBeginning() noexcept
    {
    }

    /* Overloadable */
    bool _canSeekNsFromOrigin(std::int64_t) noexcept
    {
        return false;
    }

    /* Overloadable */
    void _seekNsFromOrigin(std::int64_t) noexcept
    {
    }

    MessageIterator::Shared _createMessageIterator(const SelfComponentInputPort port)
    {
        return _mSelfMsgIter.createMessageIterator(port);
    }

    UserComponentT& _component() noexcept
    {
        return _mSelfMsgIter.component().template data<UserComponentT>();
    }

    SelfComponentOutputPort _port() noexcept
    {
        return _mSelfMsgIter.port();
    }

    bool _isInterrupted() const noexcept
    {
        return _mSelfMsgIter.isInterrupted();
    }

private:
    UserMessageIteratorT& _userObj() noexcept
    {
        return static_cast<UserMessageIteratorT&>(*this);
    }

    void _resetError() noexcept
    {
        _mExcToThrowType = _ExcToThrowType::NONE;
        _mSavedLibError.reset();
    }

    SelfMessageIterator _mSelfMsgIter;

    /*
     * next() may accumulate messages, and then catch an error before
     * returning. In that case, it saves the error of the current thread
     * here so that it can return its accumulated messages and throw the
     * next time.
     *
     * It also saves the type of the exception to throw the next time.
     */
    _ExcToThrowType _mExcToThrowType = _ExcToThrowType::NONE;

    struct LibErrorDeleter final
    {
        void operator()(const bt_error * const error) const noexcept
        {
            bt_error_release(error);
        }
    };

    std::unique_ptr<const bt_error, LibErrorDeleter> _mSavedLibError;

protected:
    bt2c::Logger _mLogger;
};

namespace internal {

template <typename UserComponentT, typename CompClsBridgeT, typename LibSpecCompClsPtrT,
          typename AsCompClsFuncT, typename SetInitMethodFuncT, typename SetFinalizeMethodFuncT,
          typename SetGetSupportedMipVersionsMethodFuncT, typename SetQueryMethodFuncT>
void setCompClsCommonProps(
    LibSpecCompClsPtrT * const libSpecCompClsPtr, AsCompClsFuncT&& asCompClsFunc,
    SetInitMethodFuncT&& setInitMethodFunc, SetFinalizeMethodFuncT&& setFinalizeMethodFunc,
    SetGetSupportedMipVersionsMethodFuncT&& setGetSupportedMipVersionsMethodFunc,
    SetQueryMethodFuncT&& setQueryMethodFunc)
{
    const auto libCompClsPtr = asCompClsFunc(libSpecCompClsPtr);

    if (UserComponentT::description != nullptr) {
        const auto status =
            bt_component_class_set_description(libCompClsPtr, UserComponentT::description);

        if (status == BT_COMPONENT_CLASS_SET_DESCRIPTION_STATUS_MEMORY_ERROR) {
            throw MemoryError {};
        }
    }

    if (UserComponentT::help != nullptr) {
        const auto status = bt_component_class_set_help(libCompClsPtr, UserComponentT::help);

        if (status == BT_COMPONENT_CLASS_SET_HELP_STATUS_MEMORY_ERROR) {
            throw MemoryError {};
        }
    }

    {
        const auto status = setInitMethodFunc(libSpecCompClsPtr, CompClsBridgeT::init);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    {
        const auto status = setFinalizeMethodFunc(libSpecCompClsPtr, CompClsBridgeT::finalize);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    {
        const auto status = setGetSupportedMipVersionsMethodFunc(
            libSpecCompClsPtr, CompClsBridgeT::getSupportedMipVersions);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    {
        const auto status = setQueryMethodFunc(libSpecCompClsPtr, CompClsBridgeT::query);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }
}

template <typename MsgIterClsBridgeT>
bt_message_iterator_class *createLibMsgIterCls()
{
    const auto libMsgIterClsPtr = bt_message_iterator_class_create(MsgIterClsBridgeT::next);

    if (!libMsgIterClsPtr) {
        throw MemoryError {};
    }

    {
        const auto status = bt_message_iterator_class_set_initialize_method(
            libMsgIterClsPtr, MsgIterClsBridgeT::init);

        BT_ASSERT(status == BT_MESSAGE_ITERATOR_CLASS_SET_METHOD_STATUS_OK);
    }

    {
        const auto status = bt_message_iterator_class_set_finalize_method(
            libMsgIterClsPtr, MsgIterClsBridgeT::finalize);

        BT_ASSERT(status == BT_MESSAGE_ITERATOR_CLASS_SET_METHOD_STATUS_OK);
    }

    return libMsgIterClsPtr;
}

template <typename UserComponentT>
bt_component_class_source *createSourceCompCls()
{
    static_assert(
        std::is_base_of<UserSourceComponent<
                            UserComponentT, typename UserComponentT::MessageIterator,
                            typename UserComponentT::InitData, typename UserComponentT::QueryData>,
                        UserComponentT>::value,
        "`UserComponentT` inherits `UserSourceComponent`");

    using CompClsBridge = internal::SrcCompClsBridge<UserComponentT>;
    using MsgIterClsBridge = internal::MsgIterClsBridge<typename UserComponentT::MessageIterator>;

    const auto libMsgIterClsPtr = createLibMsgIterCls<MsgIterClsBridge>();
    const auto libCompClsPtr =
        bt_component_class_source_create(UserComponentT::name, libMsgIterClsPtr);

    bt_message_iterator_class_put_ref(libMsgIterClsPtr);

    if (!libCompClsPtr) {
        throw MemoryError {};
    }

    setCompClsCommonProps<UserComponentT, CompClsBridge>(
        libCompClsPtr, bt_component_class_source_as_component_class,
        bt_component_class_source_set_initialize_method,
        bt_component_class_source_set_finalize_method,
        bt_component_class_source_set_get_supported_mip_versions_method,
        bt_component_class_source_set_query_method);

    {
        const auto status = bt_component_class_source_set_output_port_connected_method(
            libCompClsPtr, CompClsBridge::outputPortConnected);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    return libCompClsPtr;
}

template <typename UserComponentT>
bt_component_class_filter *createFilterCompCls()
{
    static_assert(
        std::is_base_of<UserFilterComponent<
                            UserComponentT, typename UserComponentT::MessageIterator,
                            typename UserComponentT::InitData, typename UserComponentT::QueryData>,
                        UserComponentT>::value,
        "`UserComponentT` inherits `UserFilterComponent`");

    using CompClsBridge = internal::FltCompClsBridge<UserComponentT>;
    using MsgIterClsBridge = internal::MsgIterClsBridge<typename UserComponentT::MessageIterator>;

    const auto libMsgIterClsPtr = createLibMsgIterCls<MsgIterClsBridge>();
    const auto libCompClsPtr =
        bt_component_class_filter_create(UserComponentT::name, libMsgIterClsPtr);

    bt_message_iterator_class_put_ref(libMsgIterClsPtr);

    if (!libCompClsPtr) {
        throw MemoryError {};
    }

    setCompClsCommonProps<UserComponentT, CompClsBridge>(
        libCompClsPtr, bt_component_class_filter_as_component_class,
        bt_component_class_filter_set_initialize_method,
        bt_component_class_filter_set_finalize_method,
        bt_component_class_filter_set_get_supported_mip_versions_method,
        bt_component_class_filter_set_query_method);

    {
        const auto status = bt_component_class_filter_set_input_port_connected_method(
            libCompClsPtr, CompClsBridge::inputPortConnected);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    {
        const auto status = bt_component_class_filter_set_output_port_connected_method(
            libCompClsPtr, CompClsBridge::outputPortConnected);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    return libCompClsPtr;
}

template <typename UserComponentT>
bt_component_class_sink *createSinkCompCls()
{
    static_assert(
        std::is_base_of<UserSinkComponent<UserComponentT, typename UserComponentT::InitData,
                                          typename UserComponentT::QueryData>,
                        UserComponentT>::value,
        "`UserComponentT` inherits `UserSinkComponent`");

    using CompClsBridge = internal::SinkCompClsBridge<UserComponentT>;

    const auto libCompClsPtr =
        bt_component_class_sink_create(UserComponentT::name, CompClsBridge::consume);

    if (!libCompClsPtr) {
        throw MemoryError {};
    }

    setCompClsCommonProps<UserComponentT, CompClsBridge>(
        libCompClsPtr, bt_component_class_sink_as_component_class,
        bt_component_class_sink_set_initialize_method, bt_component_class_sink_set_finalize_method,
        bt_component_class_sink_set_get_supported_mip_versions_method,
        bt_component_class_sink_set_query_method);

    {
        const auto status = bt_component_class_sink_set_graph_is_configured_method(
            libCompClsPtr, CompClsBridge::graphIsConfigured);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    {
        const auto status = bt_component_class_sink_set_input_port_connected_method(
            libCompClsPtr, CompClsBridge::inputPortConnected);

        BT_ASSERT(status == BT_COMPONENT_CLASS_SET_METHOD_STATUS_OK);
    }

    return libCompClsPtr;
}

} /* namespace internal */
} /* namespace bt2 */

#endif /* BABELTRACE_CPP_COMMON_BT2_COMPONENT_CLASS_DEV_HPP */