Refactor qdb

[elicn]

qdb refactored from ground up, overall improving feature stability, reliability and maintainability.
Note: some debug prints are still present; waiting for feedback.

Highlights:

• Misc cosmetic improvements
• Revised classes and mixin hierarchy to be more intuitive
• Consolidated and de-duplicated common functionality
• Heavily commented and documented the code, in addition to annotations
• Branch prediction greatly improved
  • Assembly analysis now based on Capstone objects rather than unreliable string parsing
  • More corner cases are now covered
  • Prediction target got more accurate
• Going backwards greatly improved
  • Now also reverting memory layout in addition to memory contents
  • Snapshot memory footprint has been reduced
• qdb commands can now evaluate compound expressions, e.g. x/8i ($pc + $sp + (4 * $r1))
• Rewrote all tests to reflect meaningful scenarios
• Bug fixes

TODO:

• Redesign classes hierarchy
• Improve snapshots by covering more operating system resources, such as file descriptors, etc.
• Make existing commands more resemble to their gdb equivalents
• Support more commands

Screenshot 1: context dump, predicting branch taken upwards

Screenshot 2: examine command taking an expression as its argument

[elicn]

@ucgJhe, would appreciate your feedback.
Once you approve, we can move on to other's reviews.

[ucgJhe]

Here are all my reviews so far. As for the capstone engine issue, not quite sure anything will be broken if we upgrade it. Everything is fine after I upgraded my local version to capstone==5.0.5, and run tests/test_onlinux.sh.

I also pushed my solutions here: https://github.com/ucgJhe/qiling/tree/refactor-qdb

[ucgJhe]

maybe only show this messages when QL_VERBOSE is DEBUG ?

[elicn]

I find the target indication quite informative actually.
Maybe change the message format to be more elegant?

[ucgJhe]

yes it's a good idea

[elicn]

I'll figure something out.

[ucgJhe]

There's also another DEBUG message in render.py. Do you think thats also nessassary ?

[elicn]

Snapshot diff prints removed.

[ucgJhe]

Looks good for me once it's fixed

[elicn]

Enabled show sub-commands as follows:

• show args [num] : Show function call arguments
• show mem [filter] : Dump memory map
• show breakpoints : List all breakpoints
• show marks : List marked symbols
• show snapshot : Show diff of last snapshot
• show entry : Show program entry point(s)

[xwings]

@elicn you approval is needed.

[elicn]

@elicn you approval is needed.

Once we get @ucgJhe's green light, we can merge.

[ucgJhe]

@elicn you approval is needed.

Once we get @ucgJhe's green light, we can merge.

I was thinking about change command show to something like info but I guess the sub-command stuff is also okay

[elicn]

I was thinking about change command show to something like info but I guess the sub-command stuff is also okay

Yes, I was thinking about renaming show to info to make it more gdb-like, but I thought you'd want to preserve your original naming. If that is what you meant, it is an easy change.

[ucgJhe]

I was thinking about change command show to something like info but I guess the sub-command stuff is also okay

Yes, I was thinking about renaming show to info to make it more gdb-like, but I thought you'd want to preserve your original naming. If that is what you meant, it is an easy change.

yes, rename to info will be better

[elicn]

@xwings, we can merge now.