Remove INET_ADDRSTRLEN limit for symbolic hostnames and optimize socket connections.

[Jakio815]

Summary

• Remove server_hostname from socket_priv_t, which was actually not necessary to save in the struct.
• Fix bug setting pointers of net_abs in stack to NULL after shutdown_net().
• Support connect_to_socket() use in_addr instead of char* hostname when available.

1. Remove server_hostname from socket_priv_t

There was a bug found in #576, which happened after merging #508, not allowing symbolic hostnames longer than 16 bytes (INET_ADDRSTRLEN) from being connected.
This happened because there was a memcpy() to save the host_name in char server_hostname[INET_ADDRSTRLEN];.

While investigating this, the code only used this for printing debug messages on the hostname, and it was never used again.
I removed the server_hostname field from socket_priv_t.

2. Bug Fix: Remove unnecessary NULL setting to pointers.

After shutdown_net(net_abs), I set all net_abs to NULL, however some were just pointers from the stack, so had no effect. Removed all of these. Thanks for reporting this @edwardalee.

3. Support connect_to_socket() use in_addr instead of char* hostname when available.

When a federate tries to connect another federate, the RTI sends the target federate's IP address in a network format (uint32_t), not the presentation format (192.168.0.1 or localhost).
However, connect_to_socket() only supported the presentation format as the input parameter.
So there was some inefficiency where federate.c does inet_ntop() to convert the recieved network format into the presentation format, and inside connect_to_socket, does getaddrinfo to convert that presentation format backward into the network format (struct sockaddr_in) to make the actual system call connect().

So, by updating connect_to_socket() to accept an optional struct in_addr*, this PR removes this redundant Network -> Presentation -> Network conversion, which removes unnecessary DNS resolution overhead.

Why we couldn't remove getaddrinfo() entirely?

The redundancy above was from lf_connect_to_federate, however, connect_to_net is used once again in lf_connect_to_rti.

However, when used in lf_connect_to_rti, this always uses the char* hostname, because the RTI's address is provided strictly as a human-readable string (e.g., "localhost", "192.168.0.1" or "rti-server.domain.com"), performing DNS resolution via getaddrinfo() is mandatory to discover its actual network routing address. Therefore, connect_to_socket() was updated to selectively bypass DNS only when a raw IP is available.

This suggestion was also made by @edwardalee, thanks for your insight!

[Copilot]

Pull request overview

This PR updates the socket-based network abstraction used by the federated runtime to (1) avoid truncating symbolic hostnames, and (2) optimize certain federate-to-federate connections by using an already-available IPv4 address directly instead of round-tripping through presentation format + DNS resolution.

Changes:

• Removed persisted server_hostname storage from socket_priv_t (fixes hostname truncation caused by INET_ADDRSTRLEN-sized buffers).
• Extended socket connection parameters to optionally pass a raw struct in_addr* and bypass getaddrinfo() when available.
• Cleaned up ineffective “set local pointer to NULL after shutdown” code paths.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
network/impl/src/socket_common.c	Removes debug hostname storage; adds connect_to_socket() fast-path using struct in_addr.
network/impl/src/lf_socket_support.c	Stops copying hostname into a fixed-size buffer; passes hostname/IP through to connect_to_socket().
network/api/socket_common.h	Adds optional server_ip_addr to connection params; removes server_hostname from socket_priv_t; updates API docs/signature.
core/federated/RTI/rti_remote.h	Updates comments to reflect removal of server_hostname tracking.
core/federated/RTI/rti_remote.c	Removes hostname-based debug log and ineffective NULL assignments after shutdown.
core/federated/federate.c	Uses server_ip_addr when connecting to federates; avoids terminating accept loop on transient accept failure.

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[edwardalee]

LGTM! I tested and am able to start a multi-machine federation now.