Combining Embedded and Interactive Python in a Debugger: A Case Study

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" summary

LLDB embeds a full Python interpreter, exposes its C++ API via a SWIG-generated module, and provides interactive, one-line and breakpoint-script entry points. Each debugger session gets a persistent Python dictionary and session dictionary isolation is enforced by copying keys and by a custom mutex/cond lock that serializes access (no true concurrency). Breakpoint scripts receive frame and location objects; a real case study uses a Python DFS to find "romeo" in a BST and uncovers a case-conversion bug, proving the approach works.

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" chapters (34)

1. 0:00Intro
2. 0:42OUTLINE
3. 1:27WHAT IS LLDB?
4. 2:18SOME USES OF THE LLDB LIBRARY
5. 3:01TARGETS & PROCESSES
6. 3:32BREAKPOINTS
7. 3:54FRAMES & STACKS
8. 5:31DESIRED GUI DEBUGGER BEHAVIOR
9. 6:20DEBUGGERS IN LLDB
10. 11:04WHY SCRIPTING IN A DEBUGGER?
11. 15:52LLDB EXTENSIONS FOR PYTHON
12. 17:38IMPLEMENTING INTERACTIVE PYTHON INTERPRETER
13. 18:43IMPLEMENTING ONE- LINE SCRIPT COMMANDS
14. 19:00HOW THE DICTIONARIES WORK (1)
15. 19:42INVOKING ONE-LINE SCRIPT COMMANDS
16. 20:20INVOKING INTERACTIVE SCRIPT INTERPRETER
17. 21:32MORE ABOUT LLOB BREAKPOINT SCRIPTS...
18. 22:45COMMANDS - CREATE
19. 23:44COMMANDS - CALL
20. 24:52BUILDING THE LLOB PYTHON API MODULE
21. 25:37PARTICULAR PROBLEMS & SOLUTIONS
22. 28:39GETTING A SINGLE OBJECT ACROSS THE DEBUGGER
23. 30:14WHY A DEBUGGER- LEVEL DICTIONARY?
24. 30:49INTERACTIVE INTERPRETER ONE LINE COMMANDS
25. 31:24BREAKPOINT COMMANDS: A PROBLEM
26. 32:34DICTIONARY SET-UP
27. 33:07DICTIONARY CLEAN-UP
28. 34:08POSSIBLE APPROACHES
29. 35:45WRITE OUR OWN!
30. 37:36EXAMPLE: SIMPLE DICTIONARY PROGRAM Store and find words in Binary Search Tree
31. 38:35THE PLAN Searching Tree Without Restarting Program
32. 39:48USING THE INTERACTIVE INTERPRETER
33. 41:43PYTHON BREAKPOINT COMMAND (At Decision to Follow Right Child)
34. 43:58SUMMARY

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