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

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" summary

LLDB embeds a full Python interpreter and a session dictionary per debugger to let users run interactive Python, attach breakpoint script commands, and call the LLDB API from Python via a SWIG-generated module. Implementation uses debugger-IDs, global-dictionary patching, and mutex/condition locking to simulate multiple interpreters in one process; access is serialized (no true parallel interpreters). Demo searches a large BST for "Romeo" (found path left left right right left) and locates the bug: uppercase R vs lowercase r. Works on macOS and Linux.

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" chapters (25)

1. 0:00Intro
2. 0:46OUTLINE
3. 3:54FRAMES & STACKS
4. 5:31DESIRED GUI DEBUGGER BEHAVIOR
5. 11:04WHY SCRIPTING IN A DEBUGGER?
6. 15:52LLDB EXTENSIONS FOR PYTHON
7. 17:37IMPLEMENTING INTERACTIVE PYTHON INTERPRETER
8. 18:43IMPLEMENTING ONE- LINE SCRIPT COMMANDS
9. 19:00HOW THE DICTIONARIES WORK (1)
10. 19:42INVOKING ONE-LINE SCRIPT COMMANDS
11. 20:20INVOKING INTERACTIVE SCRIPT INTERPRETER
12. 22:45COMMANDS - CREATE
13. 26:01PASSING POINTERS & C++ OBJECTS TO PYTHON
14. 28:39GETTING A SINGLE OBJECT ACROSS THE DEBUGGER
15. 30:14WHY A DEBUGGER- LEVEL DICTIONARY?
16. 30:49INTERACTIVE INTERPRETER & ONE LINE COMMANDS
17. 31:24BREAKPOINT COMMANDS: A PROBLEM
18. 32:34DICTIONARY SET-UP
19. 33:07DICTIONARY CLEAN-UP
20. 34:08PY NEWINTERPRETER?
21. 36:58GUI DEBUGGER PYTHON REQUIREMENTS
22. 38:35THE PLAN Searching Tree Without Restarting Program
23. 39:48USING THE INTERACTIVE INTERPRETER
24. 41:43PYTHON BREAKPOINT COMMAND (At Decision to Follow Right Child)
25. 43:58SUMMARY

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