[WIP] Added IPv6 support in the SRT protocol.

[shogo4405]

Description & motivation

• Added IPv6 support in the SRT protocol.

Type of change

• New feature (non-breaking change which adds functionality)

Screenshots:

[Copilot]

Pull request overview

This PR adds IPv6 support to the SRT protocol implementation by replacing the IPv4-specific sockaddr_in with a protocol-agnostic AddrInfo utility that uses getaddrinfo() for address resolution. This enables the library to handle both IPv4 and IPv6 addresses transparently.

Key Changes:

• Introduced new AddrInfo struct that wraps getaddrinfo() for protocol-agnostic address resolution
• Updated SRT socket connection/binding logic to use the new resolver pattern
• Removed deprecated IPv4-only sockaddr_in extension that used gethostbyname()

Reviewed changes

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

File	Description
SRTHaishinKit/Sources/Util/AddrInfo.swift	New utility struct implementing address resolution using getaddrinfo() with support for both IPv4 and IPv6
SRTHaishinKit/Sources/SRT/SRTSocketURL.swift	Updated remote and local properties to return AddrInfo instead of sockaddr_in
SRTHaishinKit/Sources/SRT/SRTSocket.swift	Refactored connection/binding logic to use AddrInfo.resolve() with proper error handling for all three SRT modes
SRTHaishinKit/Sources/Extension/sockaddr_in+Extension.swift	Removed IPv4-only extension that relied on deprecated gethostbyname()

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[Copilot]

[nitpick] Setting ai_family to AF_UNSPEC allows both IPv4 and IPv6, but the flags parameter doesn't validate which protocols are actually requested. Consider documenting this behavior or adding a parameter to allow callers to specify protocol preferences (e.g., IPv4-only, IPv6-only, or both).

Suggested change

	@discardableResult
	func resolve<R>(_ flags: Int32, lambda: (UnsafePointer<sockaddr>, Int32) throws -> R?) throws -> R {
	var hints = addrinfo(
	ai_flags: flags,
	ai_family: AF_UNSPEC,
	/**
	Resolves the host and port to a socket address.
	- Parameters:
	- flags: Flags for address resolution.
	- family: Protocol family to use (AF_INET for IPv4, AF_INET6 for IPv6, AF_UNSPEC for both). Defaults to AF_UNSPEC.
	- lambda: Closure to process each resolved address.
	- Returns: The result of the closure for the first matching address.
	- Throws: Error.failedToGetaddrinfo or Error.failedToResolve.
	*/
	@discardableResult
	func resolve<R>(_ flags: Int32, family: Int32 = AF_UNSPEC, lambda: (UnsafePointer<sockaddr>, Int32) throws -> R?) throws -> R {
	var hints = addrinfo(
	ai_flags: flags,
	ai_family: family,

[Copilot]

Using AI_PASSIVE flag for remote address resolution in rendezvous mode is incorrect. AI_PASSIVE is intended for addresses that will be used with bind(), not connect() or rendezvous connections. The remote address should use AI_ADDRCONFIG only, while only the local address should use AI_PASSIVE.

Suggested change

	return try remote.resolve(AI_PASSIVE | AI_ADDRCONFIG) { remotename, remotelen in
	return try remote.resolve(AI_ADDRCONFIG) { remotename, remotelen in

[Copilot]

The parameters to srt_rendezvous are in the wrong order. According to SRT API documentation, the function signature should have local address parameters first, then remote address parameters. This line passes them as (socket, local, local_len, remote, remote_len) but based on the old code structure and typical SRT API patterns, verify the correct parameter order.