From daaa9afdd0fba80799c3c8b6b306bdd6f3dfe9cd Mon Sep 17 00:00:00 2001
From: Biraj Parikh <birajp@gmail.com>
Date: Tue, 18 Mar 2025 21:42:36 -0700
Subject: [PATCH 1/4] feat: Get `tcp_info` structure

Implement TCP_INFO option for getsockopt.
---
 src/sys/socket/sockopt.rs | 11 +++++++++++
 test/sys/test_sockopt.rs  | 17 +++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/src/sys/socket/sockopt.rs b/src/sys/socket/sockopt.rs
index 11c3be9e13..08ae2cb1a4 100644
--- a/src/sys/socket/sockopt.rs
+++ b/src/sys/socket/sockopt.rs
@@ -1268,6 +1268,17 @@ sockopt_impl!(
     libc::SO_EXCLBIND,
     bool
 );
+#[cfg(target_os = "linux")]
+#[cfg(feature = "net")]
+sockopt_impl!(
+    #[cfg_attr(docsrs, doc(cfg(feature = "net")))]
+    /// Get tcp_info structure.
+    TcpInfo,
+    GetOnly,
+    libc::SOL_TCP,
+    libc::TCP_INFO,
+    libc::tcp_info
+);
 
 #[allow(missing_docs)]
 // Not documented by Linux!
diff --git a/test/sys/test_sockopt.rs b/test/sys/test_sockopt.rs
index 42697ffa24..2dc304fba1 100644
--- a/test/sys/test_sockopt.rs
+++ b/test/sys/test_sockopt.rs
@@ -568,6 +568,23 @@ fn test_ipv6_tclass() {
     assert_eq!(getsockopt(&fd, sockopt::Ipv6TClass).unwrap(), class);
 }
 
+#[test]
+#[cfg(target_os = "linux")]
+fn test_tcp_info() {
+    let fd = socket(
+        AddressFamily::Inet6,
+        SockType::Stream,
+        SockFlag::empty(),
+        SockProtocol::Tcp,
+    )
+    .unwrap();
+    let tcp_info = getsockopt(&fd, sockopt::TcpInfo).unwrap();
+    // Silly assert for the sake of having one in the test.
+    // There should be no retransmits because nothing is sent through the
+    // socket in the first place.
+    assert_eq!(tcp_info.tcpi_retransmits, 0);
+}
+
 #[test]
 #[cfg(target_os = "freebsd")]
 fn test_receive_timestamp() {

From 7e6cd7ebd1ec3be0cbf898423ffaf92adbc9ee63 Mon Sep 17 00:00:00 2001
From: Biraj Parikh <birajp@gmail.com>
Date: Tue, 18 Mar 2025 21:48:49 -0700
Subject: [PATCH 2/4] chore: CHANGELOG entry for TCP_INFO sockopt addition

---
 CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b673cac562..1f65a65be1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1960,6 +1960,8 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - Added `SIGINFO` in `::nix::sys::signal` for the _macos_ target as well as
   `SIGPWR` and `SIGSTKFLT` in `::nix::sys::signal` for non-_macos_ targets.
   ([#361](https://github.com/nix-rust/nix/pull/361))
+- Added `TCP_INFO` sockopt to read TCP socket information on _linux_.
+  ([#2615](https://github.com/nix-rust/nix/pull/2615))
 
 ### Changed
 - Changed the structure `IoVec` in `::nix::sys::uio`.

From 46c7bb031408925e64cd7134181ce1dee5fee3af Mon Sep 17 00:00:00 2001
From: Biraj Parikh <birajp@gmail.com>
Date: Sun, 23 Mar 2025 21:40:41 -0700
Subject: [PATCH 3/4] Update changelog with pull request 2615

---
 changelog/2615.added.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog/2615.added.md

diff --git a/changelog/2615.added.md b/changelog/2615.added.md
new file mode 100644
index 0000000000..86080626c0
--- /dev/null
+++ b/changelog/2615.added.md
@@ -0,0 +1 @@
+ Added `TCP_INFO` sockopt to read TCP socket information on _linux_.

From 7cb442625246953eab7f424f0b7d169e2ab98b32 Mon Sep 17 00:00:00 2001
From: Biraj Parikh <birajp@gmail.com>
Date: Sat, 29 Mar 2025 22:48:57 -0700
Subject: [PATCH 4/4] Revert "chore: CHANGELOG entry for TCP_INFO sockopt
 addition"

This reverts commit 7e6cd7ebd1ec3be0cbf898423ffaf92adbc9ee63.
---
 CHANGELOG.md | 2 --
 1 file changed, 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1f65a65be1..b673cac562 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1960,8 +1960,6 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - Added `SIGINFO` in `::nix::sys::signal` for the _macos_ target as well as
   `SIGPWR` and `SIGSTKFLT` in `::nix::sys::signal` for non-_macos_ targets.
   ([#361](https://github.com/nix-rust/nix/pull/361))
-- Added `TCP_INFO` sockopt to read TCP socket information on _linux_.
-  ([#2615](https://github.com/nix-rust/nix/pull/2615))
 
 ### Changed
 - Changed the structure `IoVec` in `::nix::sys::uio`.