Limit debugfile on SIGHUP

[chromatic]

When reading the code and intent around -shrinkdebugfile, this omission seemed odd.

[edtubbs]

When reading the code and intent around -shrinkdebugfile, this omission seemed odd.

Thinking this could work if it doesn't necessarily have to happen at startup https://github.com/dogecoin/dogecoin/blob/1.14.7-dev/src/init.cpp#L470.

The file could shrink during any of these macros https://github.com/dogecoin/dogecoin/blob/1.14.7-dev/src/util.h#L77C29-L92 but it's only triggered by the SIGHUP signal. So, the user would need to send it via the terminal (e.g., using 'kill') while debugging, right?

[chromatic]

We could do it that way, though I'm a little nervous about that. If I have access to your machine but not necessarily your configuration file, logs, wallet, etc then allowing me to send signals to your process to truncate your logs still gives me a nefarious mechanism to manipulate your Core experience.

"But Unky c, why would you give anyone shell access to a Core node even if you've locked down permissions?" That's a good question! That's also a risk. But it's not a strong reason to add a new risk, in my view.

[edtubbs]

To make it work a user would need to manually send the SIGHUP signal to the process as core doesn’t do this automatically.

[chromatic]

Oh, I see what you mean. Yes, that's correct. Do you think this needs further documentation, or is there something else you're looking for in this PR?

[edtubbs]

Consider updating the -shrinkdebugfile help message here to reflect that shrinking occurs via the SIGHUP signal instead of client startup.