dd86k/alicedbg

🎯 Cross-platform Debugger and Memory Scanner

dd86k

Hi there, I'm dd!

I'm interested in software engineering, system administration, telecommunications, and technical documentation.

My main programming language is the D programming language. I also know a good amount of C, C#, PHP, and JavaScript.

Available on: GitHub, Gitlab, and Codeberg.

A more complete portfolio is available online.

Active Projects

Project	Links	Description
alicedbg	GitHub, GitLab, Codeberg	Debugger toolkit and shell
aliceserver	GitHub, GitLab, Codeberg	Debugger server implementing DAP
ddhx	GitHub, GitLab	Hex viewer
ddgst	GitHub, GitLab	Hashing multithreaded utility
binco	GitHub	Binary-text encoder/decoder
sha3-d	GitHub	Keccak-f[1600,24] (SHA-3) implementation
blake2-d	GitHub	BLAKE2 implementation (s and b variants)
lateterm	GitHub, GitLab	WordPress "DOS" theme
npp_vs2012	GitHub	Notepad++ "VS2012" theme

alicedbg's Issues

Symbol demangling

Ref	Description
Module	adbg.symbol
Function	size_t adbg_symbol_demangle(char* buf, size_t bufsz, const char* sym);

Add symbol demangling.

Minimum:

• C
• MSVC C++ (stdcall?)
• GCC C++
• D

Tests:

• C
  • Probably none, usually as-is.
• C++
  • GCC C++: _ZN11RealSenseID7PreviewC1ERKNS_13PreviewConfigE to RealSenseID::Preview::Preview(RealSenseID::PreviewConfig const&)
  • http://demangler.com/
• D
  • One test per type.

Start DWARF support

Need: Kickstart support for DWARF for symbol resolution, frame handling, etc.

Typically under sections such as .debug_info, .debug_frame, etc.

• Identify which versions of DWARF that DMD uses, if used at all.
• Identify which versions of DWARF that GCC (and notably GDC) uses.
  • GDC has a special version, hinting to DWARF2.
• Identify which versions of DWARF that LDC uses.
• Write a small POC.

New wait function with filtering

Currently, the wait function only supports exceptions.

A new wait function could be something closer to what Windows currently offers, with an option to choose what to filter.

With ptrace(2), options such as PTRACE_O_TRACESYSGOOD adds the possibility to look for dlopen for "DLL events" and exec* for "new process event", PTRACE_O_TRACEFORK/PTRACE_O_TRACEVFORK/PTRACE_O_TRACECLONE for "new thread event", etc.

There aren't that many types to filter, so a uint may be acceptable for filtering options.

Not planned any time soon, but would be pretty nice to bring a feature parity.

Prototype: adbg_wait2(adbg_process_t *proc, uint filter, void function(adbg_event_t*) ucallback)

Formatted CLI output

Noticed how nice it is to use curl in scripts, things like --write-out "%{errcode}" would make alicedbg worth using in CI pipelines.

Maybe even --help-from-code?

Example Windows script:

alicedbg --write-out "%E"
IF ERRORLEVEL 1 (
	echo Debug failed with message:
	alicedbg --help-from-code %ERRORLEVEL%
)

Maybe a useful feature, but then alicedbg isn't curl. That would make the project's scope a little too broad.

Start CodeView support

Need: Kickstart support for CodeView types.

Dumper: Show file offsets for structure fields

• Base structure field (file position) + field position (offsetof)

Use as a stand-alone library

While there is the headers build type, headers generated by DMD or LDC are within one folder, which poses a multiple of issues:

1. Files with the same module name are overwritten (DMD)
2. Compiler depends on the folder hierarchy to import modules (Any)

Can't find much online. See commit message 29f3f45 for a bit more details

Possible solutions:

1. do like vibe-d and do subpackages
2. make a script that generates proper folder hierarchy + headers
   a. (optional) make it accessible via dub
3. pact all header files into one (via a script)
   a. (optional) make it accessible via dub
4. manually prep a .di file (by hand)
   a. enables doing one import (nice!)

Application: Separate dumper and debugger portions

Right now, both the debugger portion and the dumper portion fall under the same executable.

But both do absolutely different things, and shares so little code. For the functions that do, a common folder will be created.

We lose nothing separating the two, plus:

• Makes the debugger smaller.
• Dumper can have more options and existing options trimmed (--dump-xyz to --xyz).
• Separating the applications as configuration also makes it possible to switch configuration in vscode.
• Edits on dumper or debugger won't affect each other.
• Leaves space for an eventual alicetools app or similar.

Support Backtraces

With PE32 and/or ELF.

We need support for a "get symbol from address" function first...

Server

Planned feature. Made this ticket for tracking purposes.

This could be implemented as stand-alone (server/).

Protocols:

• Language Server Index Format (LSIF)
  • Used extensively by VSCode.
  • Not used for debugging.
• Debugger A Protocol (DAP)
  • Used extensively by VSCode.
  • GDB 14.1 supports it.
• GDB/MI
  • To avoid at all cost.
• DBGP
  • Used by Xdebug, a PHP tool.

Testsuite Framework

Obviously, unit testing can only cover a portion of code.

For the shell and other modules that require external tests, it'll be worthwhile to create a D script.

Things to test:

• Shell commands.
• Fuzzing input for object server.

tester.d:

• Compiles and runs example programs found in tests/automated/.
• May need to finish some APIs first.
• Support for Fuzzing (especially object server).
  • Either zzuf or AFL.
• Could be nice to check version (--ver)

Better logging, tracing

Right now, trace logs are only written to stdout, logging is very minimal, and somewhat messy.

Issues:

1. Alicedbg does not offer logging facilities.
2. Both the debugger and dumper module lack proper logging formats when it comes to debugging either apps.
3. Trace builds spam stdout, reducing visibility when debugging.
4. A little difficult to differentiate between debugger output from debuggee output.

Options:

1. Provide logging callbacks for Issue 1.
2. Have tracing output to a alicedbg.log file for Issue 3.

Solutions:

• Shell: Debug events can be formatted [adbg] event: message.
  • Fixes Issue 2 and 4.
• Shell: Debugger messages (verbose) can be formatted [adbg] debugger: message.
  • Fixes Issue 2 and 4.
• Dumper: Can be formatted dumper: message.
  • Fixes Issue 2.
• Trace output can be written to alicedbg.log and/or alicedump.log.
  • Fixes Issue 3.