bugfix(network): Close sockets that fail to bind

[tintinhamans]

UDP::Bind opens a new socket on every call and never closed it when bind failed. Transport::init retries Bind for a full second, so every attempt on a busy port leaks a socket. With the LAN lobby port 8086 already taken, for example by a second game on the same PC, I measured about 100k sockets and 70 MB of kernel pool per second. Entering the lobby runs that loop twice.

FirewallHelperClass::openSpareSocket left a spare socket that failed to bind in its slot, and the next call overwrote it.

Both now close the socket on failure.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

• Configuration used: Organization UI
• Review profile: CHILL
• Plan: Advanced
• Run ID: 3f5f9745-7341-42ba-b7d5-4abe9245d9fe

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📥 Commits

Reviewing files that changed from the base of the PR and between 21f6de1 and 95cbed3.

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📒 Files selected for processing (2)

• Core/GameEngine/Source/GameNetwork/FirewallHelper.cpp
• Core/GameEngine/Source/GameNetwork/udp.cpp

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Walkthrough

When UDP::Bind fails, it now closes the socket and resets fd to 0. The spare-socket creation path deletes the failed UDP object and sets its pointer to nullptr before returning failure.

Changes

UDP bind failure cleanup

Layer / File(s)	Summary
Clean up failed UDP binds Core/GameEngine/Source/GameNetwork/udp.cpp, Core/GameEngine/Source/GameNetwork/FirewallHelper.cpp	On bind failure, UDP::Bind closes the socket and resets fd to 0. openSpareSocket deletes the UDP object and sets its pointer to nullptr before returning FALSE.

Priority: ⬆️ High

Estimated code review effort: 2 (Simple) | ~5 minutes

Change: Bug fix

Suggested reviewers: xezon

Merge Risk: 🟡 Moderate · up to 95cbe

A POSIX bind failure may stop retries while leaving transport or spare-socket setup with a closed socket, disrupting UDP networking. Correct the bind failure status before merging.

Pre-merge checks · 4

Passed checks (4 passed)

Check name	Status	Explanation
Title check		The title clearly and concisely describes the main change: closing sockets when binding fails.
Description check		The description directly explains the socket leak, the affected retry path, and the two fixes in the changeset.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

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[greptile-apps]

Confidence Score: 5/5

[Medium impact] The PR appears safe to merge; failed sockets are closed without breaking retries or later cleanup.

Summary

Closes sockets when UDP::Bind fails and deletes failed spare-socket objects.

• Failed UDP binds now close sockets and clear spare objects.

_{Reviews (2) · Last reviewed commit: "bugfix(network): Close sockets that fail..." · Reviewed by Greptile}

[coderabbitai]

Actionable comments posted: 1

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ℹ️ Review info

⚙️ Run configuration

• Configuration used: Organization UI
• Review profile: CHILL
• Plan: Advanced
• Run ID: a6e9ab6b-2ae5-4874-b075-3ea8913b2f42

📥 Commits

Reviewing files that changed from the base of the PR and between 0e6a06c and 21f6de1.

📒 Files selected for processing (2)

• Core/GameEngine/Source/GameNetwork/FirewallHelper.cpp
• Core/GameEngine/Source/GameNetwork/udp.cpp

Included review availability: This review used your included allowance. Your plan provides up to 4 included reviews per hour; 0 remain after this review.

[Mauller]

looks good

[xezon]

Very good