import Foundation package final class ProcessPipeCapture: @unchecked Sendable {    private let handle: FileHandle    private let condition = NSCondition()    private var data = Data()    private var activeCallbacks = 0    private var isFinished = false    private var isStopping = false    private var continuation: CheckedContinuation<Void, Never>?     package init(pipe: Pipe) {        self.handle = pipe.fileHandleForReading    }     package func start() {        self.handle.readabilityHandler = { [weak self] handle in            self?.handleReadableData(from: handle)        }    }     package func finish(timeout: Duration) async -> Data {        let drainTask = Task<Void, Error> {            await self.waitUntilFinished()        }        let join = BoundedTaskJoin(sourceTask: drainTask)        _ = await join.value(joinGrace: timeout)        return self.stopAndSnapshot()    }     package func stop() {        _ = self.stopAndSnapshot()    }     private func handleReadableData(from handle: FileHandle) {        self.condition.lock()        guard !self.isStopping else {            self.condition.unlock()            return        }        self.activeCallbacks += 1        self.condition.unlock()         let chunk = handle.availableData        var continuation: CheckedContinuation<Void, Never>?         self.condition.lock()        if chunk.isEmpty {            self.isFinished = true            continuation = self.continuation            self.continuation = nil        } else {            self.data.append(chunk)        }        self.activeCallbacks -= 1        if self.activeCallbacks == 0 {            self.condition.broadcast()        }        self.condition.unlock()         if chunk.isEmpty {            handle.readabilityHandler = nil        }        continuation?.resume()    }     private func waitUntilFinished() async {        await withCheckedContinuation { continuation in            self.condition.lock()            if self.isFinished || self.isStopping {                self.condition.unlock()                continuation.resume()                return            }            self.continuation = continuation            self.condition.unlock()        }    }     private func stopAndSnapshot() -> Data {        self.handle.readabilityHandler = nil         let continuation: CheckedContinuation<Void, Never>?        let snapshot: Data        self.condition.lock()        self.isStopping = true        while self.activeCallbacks > 0 {            self.condition.wait()        }        self.isFinished = true        continuation = self.continuation        self.continuation = nil        snapshot = self.data        self.condition.unlock()         continuation?.resume()        return snapshot    }}