Add windows-specific call for OS version

Summary:
Right now, we rely on the sys_info library to get the OS version.

However, that functionality is broken for Windows: FillZpp/sys-info-rs#86
Specifically, it produces `6.2.9200` for all versions across Windows: https://fburl.com/scuba/buck2_builds/iq6hsudp

This diff swaps the check to use the winver library, which has much better
support for fetching the Windows version.

Reviewed By: JakobDegen

Differential Revision: D56546196

app/buck2_events/BUCK

@@ -8,6 +8,20 @@ rust_library(
     srcs = glob(
         ["src/**/*.rs"],
     ),
+    os_deps = [
+        (
+            "windows",
+            ["fbsource//third-party/rust:winver"],
+        ),
+        (
+            "linux",
+            ["fbsource//third-party/rust:sys-info"],
+        ),
+        (
+            "macos",
+            ["fbsource//third-party/rust:sys-info"],
+        ),
+    ],
     test_deps = ["fbsource//third-party/rust:tokio"],
     deps = [
         "fbsource//third-party/rust:anyhow",
@@ -22,7 +36,6 @@ rust_library(
         "fbsource//third-party/rust:serde",
         # @oss-disable: "fbsource//third-party/rust:serde_json", 
         "fbsource//third-party/rust:smallvec",
-        "fbsource//third-party/rust:sys-info",
         "fbsource//third-party/rust:tokio",
         "fbsource//third-party/rust:uuid",
         "//buck2/allocative/allocative:allocative",

app/buck2_events/Cargo.toml

@@ -32,3 +32,6 @@ buck2_data = { workspace = true }
 buck2_error = { workspace = true }
 buck2_util = { workspace = true }
 buck2_wrapper_common = { workspace = true }
+
+[target."cfg(windows)".dependencies]
+winver = "1"

app/buck2_events/src/metadata.rs

@@ -102,7 +102,7 @@ pub fn system_info() -> SystemInfo {
         hostname,
         username,
         os: os_type(),
-        os_version: sys_info::os_release().ok(),
+        os_version: os_version(),
     }
 }
 
@@ -119,6 +119,16 @@ fn os_type() -> String {
     }
 }
 
+#[cfg(target_os = "windows")]
+fn os_version() -> Option<String> {
+    winver::WindowsVersion::detect().map(|v| v.to_string())
+}
+
+#[cfg(any(target_os = "linux", target_os = "macos"))]
+fn os_version() -> Option<String> {
+    sys_info::os_release().ok()
+}
+
 pub fn hostname() -> Option<String> {
     static CELL: OnceLock<Option<String>> = OnceLock::new();
 
@@ -129,3 +139,20 @@ pub fn hostname() -> Option<String> {
     })
     .clone()
 }
+
+#[cfg(all(test, target_os = "windows"))]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn os_version_produces_reasonable_windows_version() {
+        let data = collect();
+        // This logic used to use the `GetVersionExW` win32 API, which
+        // always returns the value below on recent versions of windows. See
+        // https://learn.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getversionexw
+        // for more details.
+        assert_ne!(data["os_version"], "6.2.9200");
+        // This is true for both Windows 10 and Windows 11: https://learn.microsoft.com/en-us/windows/win32/sysinfo/operating-system-version
+        assert!(data["os_version"].starts_with("10.0."));
+    }
+}