# CMakeLists.txt

## Overview

`CMakeLists.txt` is the CMake build definition for the `cartographer_ros_msgs` package. It declares the message and service files, registers them with the ROS 2 interface generator, and sets up lint tests.

## Details

- **Minimum CMake version**: 3.5, set via `cmake_minimum_required(VERSION 3.5)`.
- **Project name**: `cartographer_ros_msgs`.
- **C++ standard**: Defaults to C++14 via `CMAKE_CXX_STANDARD` when not already set.
- **Compiler flags**: For GCC and Clang, `-Wall`, `-Wextra`, and `-Wpedantic` are added to `CMAKE_CXX_FLAGS`. The `pedantic` option is deliberately not used in this message package because the generated Python C extensions do not comply with it.

## Message and Service Registration

The `msg_files` variable lists all 13 message definitions under `msg/`:

```cmake
set(msg_files
  "msg/BagfileProgress.msg"
  "msg/HistogramBucket.msg"
  "msg/LandmarkEntry.msg"
  "msg/LandmarkList.msg"
  "msg/MetricFamily.msg"
  "msg/MetricLabel.msg"
  "msg/Metric.msg"
  "msg/StatusCode.msg"
  "msg/StatusResponse.msg"
  "msg/SubmapEntry.msg"
  "msg/SubmapList.msg"
  "msg/SubmapTexture.msg"
  "msg/TrajectoryStates.msg"
)
```

The `srv_files` variable lists all 7 service definitions under `srv/`:

```cmake
set(srv_files
  "srv/FinishTrajectory.srv"
  "srv/GetTrajectoryStates.srv"
  "srv/ReadMetrics.srv"
  "srv/StartTrajectory.srv"
  "srv/TrajectoryQuery.srv"
  "srv/SubmapQuery.srv"
  "srv/WriteState.srv"
)
```

## Interface Generation

`rosidl_generate_interfaces` is invoked with the project name and both file lists:

```cmake
rosidl_generate_interfaces(${PROJECT_NAME}
  ${msg_files}
  ${srv_files}
  DEPENDENCIES builtin_interfaces geometry_msgs std_msgs
  ADD_LINTER_TESTS
)
```

- `DEPENDENCIES` declares the other interface packages whose types are referenced by the definitions.
- `ADD_LINTER_TESTS` enables lint tests on the generated interfaces.

## Package Finalization

- `ament_export_dependencies(rosidl_default_runtime)` exports the runtime dependency on `rosidl_default_runtime`.
- `ament_package()` finalizes the ament package.

## Prerequisites

The file requires the following CMake packages to be found:

- `ament_cmake`
- `rosidl_default_generators`
- `builtin_interfaces`
- `geometry_msgs`
- `std_msgs`