CMake is a widely used build system for C and C++ projects, providing a flexible and powerful platform for building, testing and deploying software applications. One of its key features is the ability to define custom build targets, which can automate common tasks such as testing, building documentation, and more.
In this article, we'll explore the basics of custom build targets in CMake and show how they can be used to streamline the build process for your project.
A custom build target in CMake is a named unit of work that can be executed during the build process. Examples of common custom targets include test targets, documentation targets, and distribution targets. Custom targets are defined in CMake scripts using the add_custom_target command.
Once a custom target is defined, it can be executed like any other build target. For example, you can run a custom test target by invoking make test in the build directory. Custom targets are also integrated into the CMake build system, so they can be executed as part of a normal build, or as standalone targets.
Defining a custom build target in CMake is straightforward. You simply use the add_custom_target command and specify the target name and a list of commands to execute. For example, the following code defines a custom target called test that runs a shell script called run_tests.sh:
add_custom_target(test
COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/run_tests.sh
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
)
In this example, the COMMAND argument specifies the shell script to run, and the WORKING_DIRECTORY argument sets the current working directory for the shell script.
There are several benefits to using custom build targets in CMake:
Automation: Custom build targets automate common tasks, such as testing, building documentation, and distributing software. This can save time and effort, and reduce the likelihood of errors.
Integration: Custom build targets are fully integrated into the CMake build system, so they can be executed as part of a normal build or as standalone targets.
Flexibility: Custom build targets can be defined using any shell commands or scripts, making it possible to automate any task that can be performed from the command line.
Platform independence: CMake is designed to support cross-platform development, so custom build targets can be defined in a platform-independent way, making it easy to build and test software on multiple platforms.
Custom build targets are a powerful feature of CMake that can greatly simplify the build and testing process for your project. Understanding how to define and use custom build targets in CMake can help you automate common tasks and streamline the development process. Whether you're building a small project or a large software suite, custom build targets are an essential tool for efficient and effective software development.