Winsock Fixes

Sources/NIOCore/IO.swift

@@ -62,15 +62,15 @@ public struct IOError: Swift.Error {
         .reason(self.failureDescription)
     }
 
-    private enum Error {
+    package enum Error {
         #if os(Windows)
         case windows(DWORD)
         case winsock(CInt)
         #endif
         case errno(CInt)
     }
 
-    private let error: Error
+    package let error: Error
 
     /// The `errno` that was set for the operation.
     public var errnoCode: CInt {

Sources/NIOHTTP1Server/main.swift

@@ -16,6 +16,10 @@ import NIOCore
 import NIOHTTP1
 import NIOPosix
 
+#if os(Windows)
+import WinSDK
+#endif
+
 extension String {
     func chopPrefix(_ prefix: String) -> String? {
         if self.unicodeScalars.starts(with: prefix.unicodeScalars) {
@@ -664,7 +668,14 @@ let channel = try { () -> Channel in
     case .unixDomainSocket(let path):
         return try socketBootstrap.bind(unixDomainSocketPath: path).wait()
     case .stdio:
+        #if os(Windows)
+        return try pipeBootstrap.takingOwnershipOfDescriptors(
+            input: Int32(bitPattern: STD_INPUT_HANDLE),
+            output: Int32(bitPattern: STD_OUTPUT_HANDLE)
+        ).wait()
+        #else
         return try pipeBootstrap.takingOwnershipOfDescriptors(input: STDIN_FILENO, output: STDOUT_FILENO).wait()
+        #endif
     }
 }()
 

Sources/NIOPosix/BSDSocketAPIWindows.swift

@@ -197,7 +197,11 @@ extension NIOBSDSocket {
     ) throws -> NIOBSDSocket.Handle? {
         let socket: NIOBSDSocket.Handle = WinSDK.accept(s, addr, addrlen)
         if socket == WinSDK.INVALID_SOCKET {
-            throw IOError(winsock: WSAGetLastError(), reason: "accept")
+            let lastError = WSAGetLastError()
+            if lastError == WSAEWOULDBLOCK {
+                return nil
+            }
+            throw IOError(winsock: lastError, reason: "accept")
         }
         return socket
     }
@@ -228,7 +232,7 @@ extension NIOBSDSocket {
     ) throws -> Bool {
         if WinSDK.connect(s, name, namelen) == SOCKET_ERROR {
             let iResult = WSAGetLastError()
-            if iResult == WSAEWOULDBLOCK { return true }
+            if iResult == WSAEWOULDBLOCK { return false }
             throw IOError(winsock: WSAGetLastError(), reason: "connect")
         }
         return true

Sources/NIOPosix/BaseSocketChannel.swift

@@ -17,6 +17,9 @@
 import Atomics
 import NIOConcurrencyHelpers
 import NIOCore
+#if os(Windows)
+import WinSDK
+#endif
 
 private struct SocketChannelLifecycleManager {
     // MARK: Types

Sources/NIOPosix/SelectorGeneric.swift

@@ -217,8 +217,20 @@ internal class Selector<R: Registration> {
     #elseif os(Windows)
     @usableFromInline
     typealias EventType = WinSDK.pollfd
+    /// Array of poll file descriptors monitored by WSAPoll. The first entry is always the wakeup socket.
     @usableFromInline
-    var pollFDs = [WinSDK.pollfd]()
+    var pollFDs = [pollfd]()
+    /// Tracks indexes of file descriptors pending removal from `pollFDs`. We defer removal until after
+    /// processing all events in `whenReady0` to avoid invalidating indexes during iteration. Stored as
+    /// indexes rather than a parallel boolean array for O(1) lookup during cleanup.
+    @usableFromInline
+    var deregisteredFDs = Set<Int>()
+    /// The read end of the wakeup socket pair. This is monitored in WSAPoll to allow waking up the event loop.
+    @usableFromInline
+    var wakeupReadSocket: NIOBSDSocket.Handle = NIOBSDSocket.invalidHandle
+    /// The write end of the wakeup socket pair. Writing to this socket wakes up the event loop.
+    @usableFromInline
+    var wakeupWriteSocket: NIOBSDSocket.Handle = NIOBSDSocket.invalidHandle
     #else
     #error("Unsupported platform, no suitable selector backend (we need kqueue or epoll support)")
     #endif