Kernel/Net: Implement SO_REUSEADDR socket option storage

[po-nuvai]

Previously SO_REUSEADDR was silently ignored (printing a FIXME message but returning success). This adds proper storage of the SO_REUSEADDR value through a member variable, making setsockopt/getsockopt work correctly.

The actual bind() behavior change to allow address reuse is not yet implemented, but this makes the option work correctly for applications that set and query the option.

Changes

• Add m_reuse_address member variable to Socket class
• Implement proper setsockopt handler for SO_REUSEADDR (validates size, stores value)
• Update getsockopt to return the actual stored value instead of always 0

[timschumi]

Sockets effectively can't have reuseaddr enabled at the moment (in a meaningful way), I'd argue that if an application cares enough to read back the state then that should rightfully fail.

[BuggieBot]

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[timschumi]

Now it's just at the state from before we added the options, which breaks all the applications that the accommodations were added for in the first place.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. Thank you for your contributions!