Add support for qThreadExtraInfo

[thefaxman]

Description

Add a new sub-IDET for MultiThreadBase to respond with extra information about a thread.

Closes #104

API Stability

• This PR does not require a breaking API change

Checklist

• Implementation
  • cargo build compiles without errors or warnings
  • cargo clippy runs without errors or warnings
  • cargo fmt was run
  • All tests pass
• Documentation
  • rustdoc + approprate inline code comments
  • Updated CHANGELOG.md
  • (if appropriate) Added feature to "Debugging Features" in README.md
• If implementing a new protocol extension IDET
  • Included a basic sample implementation in examples/armv4t
  • Included output of running examples/armv4t with RUST_LOG=trace + any relevant GDB output under the "Validation" section below
  • Confirmed that IDET can be optimized away (using ./scripts/test_dead_code_elim.sh and/or ./example_no_std/check_size.sh)

Validation

GDB output

(gdb) info thread
  Id   Target Id            Frame 
* 1    Thread 1.1 (CPU Cpu) 0x55550000 in ?? ()
  2    Thread 1.2 (CPU Cop) 0x55550000 in ?? ()
(gdb) 

armv4t output

 TRACE gdbstub::protocol::recv_packet     > <-- $qThreadExtraInfo,p1.1#85
 TRACE gdbstub::protocol::response_writer > --> $43505520437075#d2
 TRACE gdbstub::protocol::recv_packet     > <-- $qThreadExtraInfo,p1.2#86
 TRACE gdbstub::protocol::response_writer > --> $43505520436f70#02

[daniel5151]

All in all, this is looking good!

[thefaxman]

I think I've addressed all the feedback - let me know if there's any additional items you'd like to see addressed

[bet4it]

Refer: https://github.com/daniel5151/gdbstub/blob/master/src/protocol/commands/_p.rs

[bet4it]

Suggested change

	let mut body = body.splitn_mut_no_panic(3, |b| *b == b',');
	let id = SpecificThreadId::try_from(ThreadId::try_from(body.next()?).ok()?).ok()?;
	let id = SpecificThreadId::try_from(ThreadId::try_from(body).ok()?).ok()?;

[thefaxman]

Updated

[daniel5151]

Looks good.

It's a bit late for me here, so I'll give it one last once-over in the morning just in case, but it should be good to go after resolving this last thing.

[daniel5151]

Thanks again for the contribution!

Once #103 lands, I'll push out 0.6.2 that includes these and other changes.

[daniel5151]

@thefaxman 0.6.2 has been released :)