CMake Utilities

This repository provides utilities for automatically detecting and configuring different target types in a CMake project based on marker .cmake files. It works on Linux and Windows, scanning your source tree for these marker files:

1. executable.cmake
2. header.cmake
3. shared.cmake
4. static.cmake
5. tests.cmake
6. extern.cmake

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How It Works

The main script:

1. Scans your source tree for these marker .cmake files.
2. Collects source/header files by looking in specific subdirectories (src, source, inc, include).
3. Creates corresponding targets (add_executable, add_library) automatically.
4. Optionally creates test executables if BUILD_TESTING is turned ON.

No test framework is used—tests are simple executables run via CTest.

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Marker Files and Scanned Directories

1. executable.cmake

Purpose: Defines a directory containing the source of an executable.

Scanned Directories:

• src/
• source/
• inc/ (headers only)

All .c, .cc, .cp, .cpp, .cxx files found are added as source files for the resulting executable. Any headers in inc/ are also included as part of the target.

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2. header.cmake

Purpose: Defines a directory containing a header-only library (an INTERFACE library in CMake).

Scanned Directories:

• include/ (headers only)

Because this creates an INTERFACE library, no source files are compiled; everything in include/ is installed and exposed to consumers.

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3. shared.cmake

Purpose: Defines a directory containing the source of a shared library.

Scanned Directories:

• src/
• source/
• inc/ (headers only)
• include/ (headers only)

Export Logic:

• An export header file is automatically generated in <binary-dir>/<target-name>/include/<target-name>_export.h.
• The library is compiled with add_library(<target> SHARED).
• An appropriate preprocessor definition (e.g., MY_LIBRARY_EXPORTS) is added to support symbol exports on different platforms.

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4. static.cmake

Purpose: Defines a directory containing the source of a static library.

Scanned Directories:

• src/
• source/
• inc/ (headers only)
• include/ (headers only)

A normal static library is compiled with add_library(<target> STATIC).

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5. tests.cmake

Purpose: Defines a directory containing test sources.

Behavior:

• Each .cpp (or other source extension) in this folder is built as a separate test executable.
• No test framework is provided; each test is a simple executable.
• When BUILD_TESTING=ON, CTest is enabled, and these executables are registered as tests (via add_test).

6. extern.cmake

Purpose: Defines a directory containing only a single script to ensure an external dependency.

Behavior:

• is included once

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Example Structure

my_project/
  .cmake_utilities/
    all.cmake
    ...
  src_shared/
    shared.cmake
    src/
      lib.cpp
    include/
      lib.hpp
  src_static/
    static.cmake
    src/
      lib_impl.cpp
  src_exec/
    executable.cmake
    src/
      main.cpp
  headers_only/
    header.cmake
    include/
      utility.hpp
  tests/
    tests.cmake
    test_something.cpp
  CMakeLists.txt

Upon configuring CMake:

• Shared, static, header, executable targets are generated automatically.
• Test executables are created and registered if BUILD_TESTING is ON.

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Usage

1. Download bootstrap.cmake from this repository (preferably a pinned version), or copy the .cmake_utilities folder locally.
2. In your top-level CMakeLists.txt, include both:

   include("${CMAKE_BINARY_DIR}/bootstrap.cmake")
   include(".cmake_utilities/all.cmake")

3. Any directory that has executable.cmake, header.cmake, shared.cmake, static.cmake, or tests.cmake will be automatically picked up and turned into the relevant target.

For more detailed information, see the inline documentation within the scripts in this repository.