From 7534b2010b2acb17f2c8df87835871c1e50c3e7b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=8E=8B=E5=AE=87=E9=80=B8?= <Strawberry_Str@hotmail.com>
Date: Sat, 7 Jun 2025 14:47:55 +0800
Subject: [PATCH 1/2] net: add cygwin support

---
 tokio/src/net/tcp/socket.rs | 28 ++++++++++++++++++++++++----
 tokio/src/net/unix/ucred.rs |  9 ++++++---
 2 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/tokio/src/net/tcp/socket.rs b/tokio/src/net/tcp/socket.rs
index 340e8e89a60..9dc1ec9e9b8 100644
--- a/tokio/src/net/tcp/socket.rs
+++ b/tokio/src/net/tcp/socket.rs
@@ -276,10 +276,20 @@ impl TcpSocket {
     ///     Ok(())
     /// }
     /// ```
-    #[cfg(all(unix, not(target_os = "solaris"), not(target_os = "illumos")))]
+    #[cfg(all(
+        unix,
+        not(target_os = "solaris"),
+        not(target_os = "illumos"),
+        not(target_os = "cygwin"),
+    ))]
     #[cfg_attr(
         docsrs,
-        doc(cfg(all(unix, not(target_os = "solaris"), not(target_os = "illumos"))))
+        doc(cfg(all(
+            unix,
+            not(target_os = "solaris"),
+            not(target_os = "illumos"),
+            not(target_os = "cygwin"),
+        )))
     )]
     pub fn set_reuseport(&self, reuseport: bool) -> io::Result<()> {
         self.inner.set_reuse_port(reuseport)
@@ -311,10 +321,20 @@ impl TcpSocket {
     ///     Ok(())
     /// }
     /// ```
-    #[cfg(all(unix, not(target_os = "solaris"), not(target_os = "illumos")))]
+    #[cfg(all(
+        unix,
+        not(target_os = "solaris"),
+        not(target_os = "illumos"),
+        not(target_os = "cygwin"),
+    ))]
     #[cfg_attr(
         docsrs,
-        doc(cfg(all(unix, not(target_os = "solaris"), not(target_os = "illumos"))))
+        doc(cfg(all(
+            unix,
+            not(target_os = "solaris"),
+            not(target_os = "illumos"),
+            not(target_os = "cygwin"),
+        )))
     )]
     pub fn reuseport(&self) -> io::Result<bool> {
         self.inner.reuse_port()
diff --git a/tokio/src/net/unix/ucred.rs b/tokio/src/net/unix/ucred.rs
index 74e596bc9b6..bdc417f1304 100644
--- a/tokio/src/net/unix/ucred.rs
+++ b/tokio/src/net/unix/ucred.rs
@@ -36,7 +36,8 @@ impl UCred {
     target_os = "redox",
     target_os = "android",
     target_os = "openbsd",
-    target_os = "haiku"
+    target_os = "haiku",
+    target_os = "cygwin"
 ))]
 pub(crate) use self::impl_linux::get_peer_cred;
 
@@ -69,7 +70,8 @@ pub(crate) use self::impl_noproc::get_peer_cred;
     target_os = "redox",
     target_os = "android",
     target_os = "openbsd",
-    target_os = "haiku"
+    target_os = "haiku",
+    target_os = "cygwin"
 ))]
 pub(crate) mod impl_linux {
     use crate::net::unix::{self, UnixStream};
@@ -83,7 +85,8 @@ pub(crate) mod impl_linux {
         target_os = "linux",
         target_os = "redox",
         target_os = "android",
-        target_os = "haiku"
+        target_os = "haiku",
+        target_os = "cygwin"
     ))]
     use libc::ucred;
 

From 8ca8a3c183d72ec62b73d591d1f19f32d72984e5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=8E=8B=E5=AE=87=E9=80=B8?= <Strawberry_Str@hotmail.com>
Date: Sat, 7 Jun 2025 15:35:39 +0800
Subject: [PATCH 2/2] ci: ignore target_os = "cygwin"

---
 Cargo.toml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Cargo.toml b/Cargo.toml
index 7ecb6eea0c7..6ed579b136d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -30,4 +30,5 @@ unexpected_cfgs = { level = "warn", check-cfg = [
   'cfg(tokio_taskdump)',
   'cfg(tokio_unstable)',
   'cfg(tokio_uring)',
+  'cfg(target_os, values("cygwin"))',
 ] }