Program Listing for File component.hpp

            

            
/*
* SPDX-FileCopyrightText: Copyright (c) 2022-2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

#ifndef HOLOSCAN_CORE_COMPONENT_HPP
#define HOLOSCAN_CORE_COMPONENT_HPP

#include <stdio.h>
#include <iostream>
#include <memory>
#include <string>
#include <type_traits>
#include <unordered_map>
#include <utility>
#include <vector>

#include "./parameter.hpp"
#include "./type_traits.hpp"
#include "./arg.hpp"
#include "./forward_def.hpp"

#define HOLOSCAN_COMPONENT_FORWARD_TEMPLATE()                                        \
template <typename ArgT,                                                           \
typename... ArgsT,                                                       \
typename = std::enable_if_t<                                             \
!std::is_base_of_v<::holoscan::ComponentBase, std::decay_t<ArgT>> && \
(std::is_same_v<::holoscan::Arg, std::decay_t<ArgT>> ||              \
std::is_same_v<::holoscan::ArgList, std::decay_t<ArgT>>)>>
#define HOLOSCAN_COMPONENT_FORWARD_ARGS(class_name) \
HOLOSCAN_COMPONENT_FORWARD_TEMPLATE()             \
class_name(ArgT&& arg, ArgsT&&... args)           \
: Component(std::forward<ArgT>(arg), std::forward<ArgsT>(args)...)

#define HOLOSCAN_COMPONENT_FORWARD_ARGS_SUPER(class_name, super_class_name) \
HOLOSCAN_COMPONENT_FORWARD_TEMPLATE()                                     \
class_name(ArgT&& arg, ArgsT&&... args)                                   \
: super_class_name(std::forward<ArgT>(arg), std::forward<ArgsT>(args)...)

namespace holoscan {

namespace gxf {
class GXFExecutor;
}  // namespace gxf

class ComponentBase {
 public:
  ComponentBase() = default;

  HOLOSCAN_COMPONENT_FORWARD_TEMPLATE()
  explicit ComponentBase(ArgT&& arg, ArgsT&&... args) {
    add_arg(std::forward<ArgT>(arg));
    (add_arg(std::forward<ArgsT>(args)), ...);
  }

  virtual ~ComponentBase() = default;

  int64_t id() const { return id_; }

  const std::string& name() const { return name_; }

  Fragment* fragment() { return fragment_; }

  void add_arg(const Arg& arg) { args_.emplace_back(arg); }
  void add_arg(Arg&& arg) { args_.emplace_back(std::move(arg)); }

  void add_arg(const ArgList& arg) {
    args_.reserve(args_.size() + arg.size());
    args_.insert(args_.end(), arg.begin(), arg.end());
  }
  void add_arg(ArgList&& arg) {
    args_.reserve(args_.size() + arg.size());
    args_.insert(
        args_.end(), std::make_move_iterator(arg.begin()), std::make_move_iterator(arg.end()));
    arg.clear();
  }

  std::vector<Arg>& args() { return args_; }

  virtual void initialize() {}

  virtual YAML::Node to_yaml_node() const;

  std::string description() const;

 protected:
  friend class holoscan::Executor;
  // Make GXFExecutor a friend class so it can call protected initialization methods
  friend class holoscan::gxf::GXFExecutor;

  // Make Fragment a friend class so it can call reset_graph_entities
  friend class holoscan::Fragment;

  void update_params_from_args(std::unordered_map<std::string, ParameterWrapper>& params);

  virtual void reset_graph_entities();

  int64_t id_ = -1;
  std::string name_ = "";
  Fragment* fragment_ = nullptr;
  std::vector<Arg> args_;
};

class Component : public ComponentBase {
 protected:
  // Make GXFExecutor a friend class so it can call protected initialization methods
  friend class holoscan::gxf::GXFExecutor;

  using ComponentBase::update_params_from_args;

  void update_params_from_args();

  virtual void set_parameters() {}

  std::shared_ptr<ComponentSpec> spec_;
};

}  // namespace holoscan

#endif/* HOLOSCAN_CORE_COMPONENT_HPP */