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In case of target directory doesn't exist, watch the parent directory first, and start watching the target directory if it is created. Throw error if parent directory doesn't exist.
jglogan
reviewed
Feb 19, 2026
DirectoryWatcher continuously check target directory, and starts watching it whenever it is created. There can be race on `DirectoryWatcher.source`, but it is benign as the while loop checks it again.
DispatchSource.eventHandler and polling loop have a race on `source`. While it is benign in this case, synchronize for better example. On the other hand, `LocalhostDNSHandler.dns` is not under race as `DispatchSource.dispatchQueue` serializes the handler executions.
jglogan
reviewed
Feb 25, 2026
| private let watcher: DirectoryWatcher | ||
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| private var dns: [String: IPv4] | ||
| nonisolated(unsafe) private var dns: [String: IPv4] |
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nonisolated(unsafe) says that the type is protected against concurrent access some other way? Is that the case here?
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Updated to use mutex. Thanks!
jglogan
approved these changes
Feb 25, 2026
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Current DirectoryWatcher fails if
/etc/resolverdoes not exist. This PR fixes DirectoryWatcher to handle non-existing/etc/resolverdirectory. If that directory does not exist, it first watches/etcdirectory to check if/etc/resolverdirectory is created later. Once it detects new/etc/resolverdirectory, it starts watching new DNS resolver files there.This PR also fixes to log the exception thrown by API server's tasks.
Resolves #1207
Type of Change
Motivation and Context
In case of non-existing
/etc/resolverstarting API server fails.Testing