Add callback exposing client source port

[rgerhards]

Summary

• extend engine and TCP structures to track client source port
• add relpEngineSetSyslogRcv3 API that passes hostname, IP, and port
• invoke new callback when available

Testing

• make -j$(nproc)
• make check

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https://chatgpt.com/codex/tasks/task_e_68bbf884f07483328ee2e5a0af8b9c1a

[Copilot]

Pull Request Overview

This PR extends the RELP library to provide client source port information to callback functions. It adds a new relpEngineSetSyslogRcv3 API that includes the client's port number along with hostname and IP address.

• Add pRemHostPort field to TCP structure to track client source port
• Implement new relpEngineSetSyslogRcv3 callback API with port parameter
• Update internal logic to extract and store port information from socket addresses

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/tcp.h	Add pRemHostPort field to store client source port
src/tcp.c	Extract port from socket address and manage memory allocation
src/scsyslog.c	Invoke new callback with port parameter when available
src/relp.h	Add onSyslogRcv3 callback function pointer to engine structure
src/relp.c	Implement new API function and dummy callback
src/librelp.h	Export new relpEngineSetSyslogRcv3 API function

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[gemini-code-assist]

Code Review

This pull request adds a new callback to expose the client's source port, which is a useful enhancement. The implementation looks mostly correct.

My main concern is with the error handling in src/tcp.c where the getnameinfo() call is updated. The new error handling is less robust than the previous version and could lead to issues if getnameinfo() fails. I've left a specific comment with a suggestion to fix this.

Additionally, there are several formatting changes throughout the pull request, mainly replacing tabs with spaces for indentation. This makes the diff harder to read and introduces style inconsistencies. It would be great if these formatting changes could be reverted to keep the focus on the logical changes and maintain a consistent coding style across the project.