Rotate daemon log on startup

2 files changed, 16 insertions, 21 deletions

diff --git a/mullvad-daemon/src/logging.rs b/mullvad-daemon/src/logging.rs
index 89154ff20e..958d5321e6 100644
--- a/mullvad-daemon/src/logging.rs
+++ b/mullvad-daemon/src/logging.rs
@@ -8,7 +8,7 @@ use log;
 use std::fmt;
 use std::fs;
 use std::io;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 
 error_chain! {
     errors {
@@ -19,6 +19,7 @@ error_chain! {
     }
     foreign_links {
         SetLoggerError(log::SetLoggerError);
+        Io(io::Error);
     }
 }
 
@@ -71,9 +72,7 @@ pub fn init_logger(
     top_dispatcher = top_dispatcher.chain(stdout_dispatcher);
 
     if let Some(ref log_file) = log_file {
-        if let Some(parent) = log_file.parent() {
-            fs::create_dir_all(parent).chain_err(|| ErrorKind::CreateDirError(parent.to_owned()))?;
-        }
+        rotate_log(log_file)?;
         let file_formatter = Formatter {
             output_timestamp: true,
             output_color: false,
@@ -139,3 +138,15 @@ fn escape_newlines(text: String) -> String {
 fn escape_newlines(text: String) -> String {
     text.replace("\n", LINE_SEPARATOR)
 }
+
+pub fn rotate_log(file: &Path) -> Result<()> {
+    let backup = file.with_extension("old.log");
+    fs::rename(file, backup).unwrap_or_else(|error| {
+        if error.kind() != io::ErrorKind::NotFound {
+            warn!("Failed to rotate log file ({})", error);
+        }
+    });
+
+    fs::File::create(file).chain_err(|| "Unable to create new log file")?;
+    Ok(())
+}
diff --git a/mullvad-daemon/src/main.rs b/mullvad-daemon/src/main.rs
index cc0bf33a0d..5c18584b1f 100644
--- a/mullvad-daemon/src/main.rs
+++ b/mullvad-daemon/src/main.rs
@@ -734,7 +734,7 @@ impl Daemon {
                 TunnelEndpointData::Wireguard(_) => WIREGUARD_LOG_FILENAME,
             };
             let tunnel_log = log_dir.join(filename);
-            Self::prepare_tunnel_log_file(&tunnel_log)?;
+            logging::rotate_log(&tunnel_log).chain_err(|| "Unable to rotate tunnel log")?;
             Some(tunnel_log)
         } else {
             None
@@ -751,22 +751,6 @@ impl Daemon {
         ).chain_err(|| ErrorKind::TunnelError("Unable to start tunnel monitor"))
     }
 
-    fn prepare_tunnel_log_file(file: &PathBuf) -> Result<()> {
-        let mut backup = file.clone();
-        backup.set_extension("old.log");
-        fs::rename(file, backup).unwrap_or_else(|error| {
-            if error.kind() != io::ErrorKind::NotFound {
-                warn!(
-                    "Failed to create backup of previous tunnel log file ({})",
-                    error
-                );
-            }
-        });
-
-        fs::File::create(file).chain_err(|| "Unable to create the tunnel log file")?;
-        Ok(())
-    }
-
     fn spawn_tunnel_monitor_wait_thread(&self, tunnel_monitor: TunnelMonitor) {
         let error_tx = self.tx.clone();
         thread::spawn(move || {