Book Image

Mastering Embedded Linux Programming - Third Edition

By : Frank Vasquez, Chris Simmonds
5 (3)
Book Image

Mastering Embedded Linux Programming - Third Edition

5 (3)
By: Frank Vasquez, Chris Simmonds

Overview of this book

If you’re looking for a book that will demystify embedded Linux, then you’ve come to the right place. Mastering Embedded Linux Programming is a fully comprehensive guide that can serve both as means to learn new things or as a handy reference. The first few chapters of this book will break down the fundamental elements that underpin all embedded Linux projects: the toolchain, the bootloader, the kernel, and the root filesystem. After that, you will learn how to create each of these elements from scratch and automate the process using Buildroot and the Yocto Project. As you progress, the book will show you how to implement an effective storage strategy for flash memory chips and install updates to a device remotely once it’s deployed. You’ll also learn about the key aspects of writing code for embedded Linux, such as how to access hardware from apps, the implications of writing multi-threaded code, and techniques to manage memory in an efficient way. The final chapters demonstrate how to debug your code, whether it resides in apps or in the Linux kernel itself. You’ll also cover the different tracers and profilers that are available for Linux so that you can quickly pinpoint any performance bottlenecks in your system. By the end of this Linux book, you’ll be able to create efficient and secure embedded devices using Linux.
Table of Contents (27 chapters)
1
Section 1: Elements of Embedded Linux
10
Section 2: System Architecture and Design Decisions
18
Section 3: Writing Embedded Applications
22
Section 4: Debugging and Optimizing Performance

Understanding BitBake syntax and semantics

BitBake is a task runner. It is similar to GNU make in that respect, except that it operates on recipes instead of makefiles. The metadata in these recipes defines tasks in shell and Python. BitBake itself is written in Python. The OpenEmbedded project that Yocto is based on consists of BitBake and a large collection of recipes for building embedded Linux distributions. BitBake's power lies in its ability to run tasks in parallel while still satisfying inter-task dependencies. Its layered and inheritance-based approach to metadata enables Yocto to scale in ways Buildroot-based build systems simply cannot.

In Chapter 6, Selecting a Build System, we learned about the five types of BitBake metadata files; that is, .bb, .bbappend, .inc, .bbclass, and .conf. We also wrote BitBake recipes for building a basic helloworld program and nova-image image. Now, we will look more closely at the contents of BitBake metadata files. We know that tasks...