Modern CMake for C++: Discover a better approach to building, testing, and packaging your software

Cover....1

Title page....2

Copyright and Credits....3

Dedications....4

Contributors....5

Table of Contents....8

Preface....16

Section 1: Introducing CMake....22

Chapter 1: First Steps with CMake....24

Technical requirements....25

Understanding the basics....26

What is CMake?....26

How does it work?....28

Installing CMake on different platforms ....31

Docker....32

Windows....33

Linux....34

macOS....34

Building from the source....35

Mastering the command line....35

CMake....36

CTest....47

CPack....48

The CMake GUI....49

CCMake....50

Navigating the project files....51

The source tree....51

The build tree....51

Listfiles....52

CMakeLists.txt....53

CMakeCache.txt....54

The Config-files for packages....55

The cmake_install.cmake, CTestTestfile.cmake, and CPackConfig.cmake files....56

CMakePresets.json and CMakeUserPresets.json....56

Ignoring files in Git....60

Discovering scripts and modules....61

Scripts....61

Utility modules....62

Find-modules....62

Summary....63

Further reading....63

Chapter 2: The CMake Language....64

Technical requirements....65

The basics of the CMake Language syntax....66

Comments....66

Command invocations....68

Command arguments....70

Working with variables ....74

Variable references....75

Using the environment variables....76

Using the cache variables....78

How to correctly use the variable scope in CMake....80

Using lists....82

Understanding control structures in CMake ....84

Conditional blocks....84

Loops....89

Command definitions....91

Useful commands....97

The message() command....97

The include() command....99

The include_guard() command....100

The file() command....100

The execute_process() command....100

Summary....101

Further reading....102

Chapter 3: Setting Up Your First CMake Project....104

Technical requirements....105

Basic directives and commands....106

Specifying the minimum CMake version – cmake_minimum_required()....106

Defining languages and metadata – project()....107

Partitioning your project....108

Scoped subdirectories....111

Nested projects....113

External projects....113

Thinking about the project structure....114

Scoping the environment....120

Discovering the operating system....120

Cross-compilation – what are host and target systems?....121

Abbreviated variables....121

Host system information....122

Does the platform have 32-bit or 64-bit architecture?....123

What is the endianness of the system?....124

Configuring the toolchain....124

Setting the C++ standard....124

Insisting on standard support....125

Vendor-specific extensions....126

Interprocedural optimization....126

Checking for supported compiler features....127

Compiling a test file....127

Disabling in-source builds....129

Summary....131

Further reading....132

Section 2: Building With CMake....134

Chapter 4: Working with Targets....136

Technical requirements....137

The concept of a target....137

Dependency graph....139

Visualizing dependencies....142

Target properties....143

What are transitive usage requirements?....144

Dealing with conflicting propagated properties....147

Meet the pseudo targets....149

Build targets....151

Writing custom commands....152

Using a custom command as a generator....153

Using a custom command as a target hook....155

Understanding generator expressions....156

General syntax....157

Types of evaluation....158

Examples to try out....165

Summary....169

Further reading....169

Chapter 5: Compiling C++ Sources with CMake....172

Technical requirements....173

The basics of compilation....173

How compilation works....174

Initial configuration....176

Managing sources for targets....177

Preprocessor configuration....179

Providing paths to included files....179

Preprocessor definitions....180

Configuring the headers....183

Configuring the optimizer....185

General level....186

Function inlining....188

Loop unrolling....189

Loop vectorization....191

Managing the process of compilation....192

Reducing compilation time....192

Finding mistakes....197

Summary....203

Further reading....204

Chapter 6: Linking with CMake....206

Technical requirements....207

Getting the basics of linking right....207

Building different library types....212

Static libraries....212

Shared libraries....213

Shared modules....214

Position-independent code....214

Solving problems with the One Definition Rule....215

Dynamically linked duplicated symbols....218

Use namespaces – don't count on a linker....220

The order of linking and unresolved symbols....221

Separating main() for testing....223

Summary....226

Further reading....227

Chapter 7: Managing Dependencies with CMake....228

Technical requirements....229

How to find installed packages....230

Discovering legacy packages with FindPkgConfig....236

Writing your own find-modules ....240

Working with Git repositories....245

Providing external libraries through Git submodules....245

Git-cloning dependencies for projects that don't use Git....249

Using ExternalProject and FetchContent modules....250

ExternalProject....251

FetchContent....257

Summary....261

Further reading....262

Section 3: Automating With CMake....264

Chapter 8: Testing Frameworks....266

Technical requirements....267

Why are automated tests worth the trouble?....267

Using CTest to standardize testing in CMake....269

Build-and-test mode....271

Test mode....272

Creating the most basic unit test for CTest....278

Structuring our projects for testing....284

Unit-testing frameworks....288

Catch2....289

GTest....292

GMock....295

Generating test coverage reports....302

Avoiding the SEGFAULT gotcha....308

Summary....308

Further reading....309

Chapter 9: Program Analysis Tools....312

Technical requirements....313

Enforcing the formatting....313

Using static checkers....318

Clang-Tidy....322

Cpplint....322

Cppcheck....322

include-what-you-use....323

Link what you use....323

Dynamic analysis with Valgrind....324

Memcheck....324

Memcheck-Cover....329

Summary....331

Further reading....332

Chapter 10: Generating Documentation....334

Technical requirements....335

Adding Doxygen to your project....335

Generating documentation with a modern look....342

Summary....344

Further reading....345

Other documentation generation utilities....345

Chapter 11: Installing and Packaging....346

Technical requirements....347

Exporting without installation....347

Installing projects on the system....351

Installing logical targets....353

Low-level installation....357

Invoking scripts during installation....365

Creating reusable packages....367

Understanding the issues with relocatable targets....367

Installing target export files....369

Writing basic config-files....371

Creating advanced config-files....374

Generating package version files....378

Defining components....380

How to use components in find_package()....380

How to use components in the install() command....381

Packaging with CPack....383

Summary....387

Further reading....388

Chapter 12: Creating Your Professional Project....390

Technical requirements....391

Planning our work....392

Project layout....396

Object libraries....397

Shared libraries versus static libraries....397

Project file structure....398

Building and managing dependencies....400

Building the Calc library....402

Building the Calc Console executable....404

Testing and program analysis....409

Preparing the coverage module....411

Preparing the Memcheck module....413

Applying testing scenarios....414

Adding static analysis tools....417

Installing and packaging....419

Installation of the library....420

Installation of the executable....421

Packaging with CPack....422

Providing the documentation....422

Automatic documentation generation....423

Not-so-technical documents of professional project....425

Summary....428

Further reading....429

Appendix: Miscellaneous Commands....432

The string() command....433

Search and replace....433

Manipulation....434

Comparison....435

Hashing....435

Generation....435

JSON....436

The list() command....437

Reading....437

Searching....437

Modification....438

Ordering....439

The file() command....439

Reading....439

Writing....440

Filesystem....440

Path conversion....441

Transfer....441

Locking....441

Archiving....442

The math() command....442

Index....444

Other Books You May Enjoy....457

Creating top-notch software is an extremely difficult undertaking. Developers researching the subject have difficulty determining which advice is up to date and which approaches have already been replaced by easier, better practices. At the same time, most online resources offer limited explanation, while also lacking the proper context and structure.

This book offers a simpler, more comprehensive, experience as it treats the subject of building C++ solutions holistically. Modern CMake for C++ is an end-to-end guide to the automatization of complex tasks, including building, testing, and packaging. You'll not only learn how to use the CMake language in CMake projects, but also discover what makes them maintainable, elegant, and clean. The book also focuses on the structure of source directories, building targets, and packages. As you progress, you'll learn how to compile and link executables and libraries, how those processes work, and how to optimize builds in CMake for the best results. You'll understand how to use external dependencies in your project - third-party libraries, testing frameworks, program analysis tools, and documentation generators. Finally, you'll get to grips with exporting, installing, and packaging for internal and external purposes.

By the end of this book, you'll be able to use CMake confidently on a professional level.

What you will learn

• Understand best practices for building C++ code
• Gain practical knowledge of the CMake language by focusing on the most useful aspects
• Use cutting-edge tooling to guarantee code quality with the help of tests and static and dynamic analysis
• Discover how to manage, discover, download, and link dependencies with CMake
• Build solutions that can be reused and maintained in the long term
• Understand how to optimize build artifacts and the build process itself

Who this book is for

The book is for build engineers and software developers with knowledge of C/C++ programming who are looking to learn CMake to automate the process of building small and large software solutions. If you are someone who's just getting started with CMake, a long-time GNU Make user, or simply looking to brush up on the latest best practices, this book is for you.