[PATCH proxmox-backup] pbs-key-config: align fsync behavior when storing new/existing key

[Christian Ebner <c.ebner@proxmox.com>]

In case a key is stored by replacing the file contents, the file
contents are synced to disk as the corresponding flag is set for
proxmox-sys::fs::replace_file(). When creating a new file however,
fsync is never called.

Align the behaviour by also calling fsync in case of storing the key
to a new file.

Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
---
Noticed while evaluating to reuse this method to store key
information to be used by push sync jobs.

 pbs-key-config/src/lib.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pbs-key-config/src/lib.rs b/pbs-key-config/src/lib.rs
index 0bcd5338c..71a49dd78 100644
--- a/pbs-key-config/src/lib.rs
+++ b/pbs-key-config/src/lib.rs
@@ -1,5 +1,6 @@
 use std::io::Write;
 use std::path::Path;
+use std::os::fd::AsRawFd;
 
 use anyhow::{bail, format_err, Context, Error};
 use serde::{Deserialize, Serialize};
@@ -254,6 +255,7 @@ impl KeyConfig {
                     .open(path)?;
 
                 file.write_all(data.as_bytes())?;
+                nix::unistd::fsync(file.as_raw_fd())?;
             }
 
             Ok(())
-- 
2.47.3