How to successfully contribute code to Free Software Projects

These few pages are the base for a short three-part tutorial on how to contribute code to Free Software projects in order for the contributions to become "mainline" with as few delays and frustrations as possible.

Part 1 - Overview

• Understand the project (e.g. U-Boot design principles)
• Requirements

Part 2 - Tools

• Source formating
  • Lindent script bundled with Linux. UsingLindentWithEmacs
  • Syntax sensitive editors (e.g. M-x c-set-style in GNU/Emacs)
  • Whitespace checkers (in git-am and e.g. M-x whitespace-global-mode in GNU/Emacs)
• Versioning system
  • Git (Official tutorial and my own Git fly through)
  • Gitk
  • StGit
  • tig
• Use available checkers
  • Use -Wall and handle all warnings!
  • Static analysers (in Linux)
    • checkstack - Generate a list of stack hogs
    • namespacecheck - Name space analysis on compiled kernel
    • headers_check - Sanity check on exported headers
  • Sparse (in Linux)

Part 3 - Examples and details (inside Linux)

• Common problems with CodingStyle
• Volatile considered harmful
• Programming endianness clean
• Abstracting from architectures with IO accessor macros
• Use spinlocks, e.g. program for SMP even on UP