fix(ecstore): support Windows checkpoint CAS

crates/ecstore/src/disk/local.rs

@@ -8073,7 +8073,25 @@ impl DiskAPI for LocalDisk {
             .map_err(DiskError::from)??);
         }
 
-        #[cfg(not(unix))]
+        #[cfg(windows)]
+        {
+            let file_path = self.io_get_object_path(volume, path)?;
+            let sync_metadata = effective_durability(volume).syncs_commit_metadata();
+            let publication_root = self.publication_root.clone();
+            return Ok(tokio::task::spawn_blocking(move || {
+                os::compare_and_update_control_file(
+                    &file_path,
+                    expected.as_deref(),
+                    replacement.as_deref(),
+                    sync_metadata,
+                    &publication_root,
+                )
+            })
+            .await
+            .map_err(DiskError::from)??);
+        }
+
+        #[cfg(not(any(unix, windows)))]
         {
             let _ = (volume, path, expected, replacement);
             Err(DiskError::MethodNotAllowed)
@@ -21828,9 +21846,9 @@ mod test {
         assert!(matches!(results[1].as_ref().unwrap_err(), DiskError::Io(_)));
     }
 
-    #[cfg(unix)]
+    #[cfg(any(unix, windows))]
     #[tokio::test]
-    async fn conditional_file_update_never_deletes_a_new_owner() {
+    async fn windows_and_unix_conditional_file_update_never_deletes_a_new_owner() {
         use tempfile::tempdir;
 
         let dir = tempdir().expect("temp dir should be created");
@@ -21861,8 +21879,18 @@ mod test {
             disk.read_all(RUSTFS_META_BUCKET, HEALING_MARKER_PATH)
                 .await
                 .expect("new owner marker should remain"),
-            owner_b
+            owner_b.clone()
         );
+        assert_eq!(
+            disk.compare_and_update_file(RUSTFS_META_BUCKET, HEALING_MARKER_PATH, Some(owner_b), None)
+                .await
+                .expect("current owner should remove marker"),
+            ConditionalFileUpdate::Updated
+        );
+        assert!(matches!(
+            disk.read_all(RUSTFS_META_BUCKET, HEALING_MARKER_PATH).await,
+            Err(DiskError::FileNotFound)
+        ));
     }
 
     #[cfg(unix)]
@@ -21901,6 +21929,40 @@ mod test {
         assert!(matches!(err, DiskError::Io(ref err) if err.kind() == ErrorKind::WouldBlock));
     }
 
+    #[cfg(windows)]
+    #[tokio::test]
+    async fn windows_conditional_file_update_returns_would_block_when_marker_lock_is_contended() {
+        let dir = tempfile::tempdir().expect("temp dir should be created");
+        let endpoint = Endpoint::try_from(dir.path().to_str().expect("temp dir should be utf8")).expect("endpoint should parse");
+        let disk = LocalDisk::new(&endpoint, false).await.expect("local disk should be created");
+        ensure_test_volume(&disk, RUSTFS_META_BUCKET).await;
+        let marker_path = disk
+            .get_object_path(RUSTFS_META_BUCKET, HEALING_MARKER_PATH)
+            .expect("marker path should resolve");
+        let lock_path = marker_path
+            .parent()
+            .expect("marker path should have a parent")
+            .join(".rustfs-cas.lock");
+        let lock = std::fs::OpenOptions::new()
+            .create(true)
+            .truncate(false)
+            .read(true)
+            .write(true)
+            .open(lock_path)
+            .expect("marker lock should open");
+        lock.try_lock().expect("marker lock should be held");
+
+        let err = tokio::time::timeout(
+            Duration::from_secs(1),
+            disk.compare_and_update_file(RUSTFS_META_BUCKET, HEALING_MARKER_PATH, None, Some(Bytes::from_static(b"owner"))),
+        )
+        .await
+        .expect("contended conditional update must not block")
+        .expect_err("contended conditional update must retry");
+
+        assert!(matches!(err, DiskError::Io(ref err) if err.kind() == ErrorKind::WouldBlock));
+    }
+
     #[cfg(target_os = "linux")]
     #[tokio::test]
     async fn replacement_io_paths_stay_under_the_mount_lease() {

crates/ecstore/src/disk/os.rs

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#[cfg(windows)]
+use crate::disk::ConditionalFileUpdate;
 use crate::disk::error::DiskError;
 use crate::disk::error::Result;
 use crate::disk::error_conv::to_file_error;
@@ -3458,6 +3460,89 @@ fn read_windows_relative_file(file_path: &Path, parent_guard: &ExistingBaseDirec
     Ok(Some(data))
 }
 
+#[cfg(windows)]
+pub(crate) fn compare_and_update_control_file(
+    file_path: &Path,
+    expected: Option<&[u8]>,
+    replacement: Option<&[u8]>,
+    sync_metadata: bool,
+    publication_root: &PublicationRoot,
+) -> io::Result<ConditionalFileUpdate> {
+    use windows_sys::{
+        Wdk::Storage::FileSystem::{
+            FILE_NON_DIRECTORY_FILE, FILE_OPEN, FILE_OPEN_IF, FILE_OPEN_REPARSE_POINT, FILE_SYNCHRONOUS_IO_NONALERT,
+        },
+        Win32::Storage::FileSystem::{
+            DELETE, FILE_ATTRIBUTE_NORMAL, FILE_READ_ATTRIBUTES, FILE_SHARE_READ, FILE_SHARE_WRITE, FILE_WRITE_DATA, SYNCHRONIZE,
+        },
+    };
+
+    let parent = file_path
+        .parent()
+        .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidInput, "conditional file has no parent"))?;
+    let parent_guard = lock_windows_directory_tree(parent, Some(parent), publication_root)?;
+    let lock = open_windows_relative(
+        parent_guard.last_handle()?,
+        std::ffi::OsStr::new(".rustfs-cas.lock"),
+        SYNCHRONIZE | FILE_READ_ATTRIBUTES | FILE_WRITE_DATA,
+        FILE_SHARE_READ | FILE_SHARE_WRITE,
+        FILE_OPEN_IF,
+        FILE_NON_DIRECTORY_FILE | FILE_OPEN_REPARSE_POINT | FILE_SYNCHRONOUS_IO_NONALERT,
+        FILE_ATTRIBUTE_NORMAL,
+        true,
+    )?;
+    validate_windows_owned_file(&lock)?;
+    match lock.as_file().try_lock() {
+        Ok(()) => {}
+        Err(std::fs::TryLockError::WouldBlock) => return Err(io::Error::from(io::ErrorKind::WouldBlock)),
+        Err(std::fs::TryLockError::Error(err)) => return Err(err),
+    }
+
+    let current = read_windows_relative_file(file_path, &parent_guard)?;
+    let matches = match (&current, expected) {
+        (None, None) => true,
+        (Some(current), Some(expected)) => current.as_slice() == expected,
+        _ => false,
+    };
+    if !matches {
+        return Ok(match current {
+            None => ConditionalFileUpdate::Missing,
+            Some(_) => ConditionalFileUpdate::Mismatch,
+        });
+    }
+
+    match replacement {
+        Some(replacement) => RenameDestinationPathGuard {
+            directory: parent.to_path_buf(),
+            _directory_guard: parent_guard,
+        }
+        .write_file_for_path_access(file_path, replacement, sync_metadata, sync_metadata)?,
+        None => {
+            let file_name = file_path
+                .file_name()
+                .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidInput, "conditional file must have a name"))?;
+            let file = open_windows_relative(
+                parent_guard.last_handle()?,
+                file_name,
+                DELETE | SYNCHRONIZE | FILE_READ_ATTRIBUTES,
+                FILE_SHARE_READ,
+                FILE_OPEN,
+                FILE_NON_DIRECTORY_FILE | FILE_OPEN_REPARSE_POINT | FILE_SYNCHRONOUS_IO_NONALERT,
+                0,
+                true,
+            )?;
+            validate_windows_owned_file(&file)?;
+            set_windows_file_delete_on_close(&file, true)?;
+            drop(file);
+            if sync_metadata {
+                fsync_dir_std(parent)?;
+            }
+        }
+    }
+
+    Ok(ConditionalFileUpdate::Updated)
+}
+
 #[cfg(windows)]
 fn open_windows_directory_component(
     parent: &WindowsDirectoryHandle,