Bret Comnes
658e5ac06f
This reverts commit 526f1594daec073269c3e70ee7914f6dd8740d5c. This revert is necessary because the change breaks mDNS hostname stability whenever a DNS-SD service calls UnregisterService. When a service unregisters (e.g. on process restart), manager_refresh_rrs() clears and re-adds all RRs in PROBING state, which sends a multicast announcement (QR=1). The kernel reflects this back to resolved's own socket. Because the local-address check was moved inside the query-only branch by the reverted commit, the reply path in on_mdns_packet() is now unguarded. The looped-back announcement matches the pending probe transaction and completes it with DNS_TRANSACTION_SUCCESS. Since the zone item is still in PROBING state (not ESTABLISHED), dns_zone_item_notify() sets we_lost=true and calls dns_zone_item_conflict(), which invokes manager_next_hostname() and renames the hostname (e.g. foo.local → foo4.local). This happens reliably on every restart of any service using RegisterService/UnregisterService (homebridge, avahi-compat wrappers, etc.). The top-level local-address check in on_mdns_packet() suppresses all looped-back multicast traffic before the reply/query split. Restoring it there is consistent with the overall design: dns_scope_check_conflicts() already has its own manager_packet_from_local_address() guard and is unaffected. A more targeted long-term fix (e.g. guarding dns_transaction_process_reply() for mDNS, or avoiding unnecessary re-probing of already-established records in manager_refresh_rrs()) can be pursued separately.
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