From 88d6a1fd9b4b62729bd55a76e727f5f1d0aeef20 Mon Sep 17 00:00:00 2001
From: David Carlier <devnexen@gmail.com>
Date: Tue, 20 Dec 2022 10:01:49 +0000
Subject: [PATCH] adding KERNEL_VERSION macro for linux.

---
 libc-test/semver/linux.txt             |  1 +
 libc-test/test/linux_kernel_version.rs | 17 +++++++++++++++++
 src/unix/linux_like/mod.rs             |  8 ++++++++
 3 files changed, 26 insertions(+)
 create mode 100644 libc-test/test/linux_kernel_version.rs

diff --git a/libc-test/semver/linux.txt b/libc-test/semver/linux.txt
index 087b1fc10c586..688dbd4778b7f 100644
--- a/libc-test/semver/linux.txt
+++ b/libc-test/semver/linux.txt
@@ -1146,6 +1146,7 @@ J1939_PGN_ADDRESS_COMMANDED
 J1939_PGN_MAX
 J1939_PGN_PDU1_MAX
 J1939_PGN_REQUEST
+KERNEL_VERSION
 KEYCTL_ASSUME_AUTHORITY
 KEYCTL_CHOWN
 KEYCTL_CLEAR
diff --git a/libc-test/test/linux_kernel_version.rs b/libc-test/test/linux_kernel_version.rs
new file mode 100644
index 0000000000000..c5687edad5601
--- /dev/null
+++ b/libc-test/test/linux_kernel_version.rs
@@ -0,0 +1,17 @@
+//! Compare libc's KERNEL_VERSION macro against a specific kernel version.
+
+extern crate libc;
+
+#[cfg(
+    target_os = "linux",
+)]
+mod t {
+    use libc;
+
+    #[test]
+    fn test_kernel_version() {
+        unsafe {
+            assert_eq!(libc::KERNEL_VERSION(6, 0, 0), 393216);
+        }
+    }
+}
diff --git a/src/unix/linux_like/mod.rs b/src/unix/linux_like/mod.rs
index 8e738d87b889f..e2e73b3300e2a 100644
--- a/src/unix/linux_like/mod.rs
+++ b/src/unix/linux_like/mod.rs
@@ -1615,6 +1615,14 @@ safe_f! {
     pub {const} fn IPTOS_ECN(x: u8) -> u8 {
         x & ::IPTOS_ECN_MASK
     }
+
+    #[allow(ellipsis_inclusive_range_patterns)]
+    pub {const} fn KERNEL_VERSION(a: u32, b: u32, c: u32) -> u32 {
+        ((a << 16) + (b << 8)) + match c {
+            0 ... 255 => c,
+            _ => 255,
+        }
+    }
 }
 
 extern "C" {