fix logging issues

- clear dgram buffer before sending to journald
- only change pretty alignment to be bigger

lib/logging/journald.ml

@@ -6,14 +6,14 @@ type t = {
   mutex : Mutex.t;
   sock_fd : Unix.file_descr;
   dest : Unix.sockaddr;
-  dgram : Buffer.t;
+  buf : Buffer.t;
 }
 
 let make ?(path = default_socket_path) () = {
   mutex = Mutex.create ();
   sock_fd = Unix.socket PF_UNIX SOCK_DGRAM 0 ~cloexec:true;
   dest = ADDR_UNIX path;
-  dgram = Buffer.create 256;
+  buf = Buffer.create 256;
 }
 
 let add_field dgram key value =
@@ -38,9 +38,10 @@ let syslog_priority = function
 let writer t ~ts ~ns ~lvl msg =
   let dgram =
     Mutex.protect t.mutex @@ fun () ->
+    Buffer.clear t.buf;
     ignore ts;
-    add_field t.dgram "MESSAGE" (Printf.sprintf "%s: %s" ns msg);
-    add_field t.dgram "PRIORITY" (syslog_priority lvl);
-    Buffer.to_bytes t.dgram
+    add_field t.buf "MESSAGE" (Printf.sprintf "%s: %s" ns msg);
+    add_field t.buf "PRIORITY" (syslog_priority lvl);
+    Buffer.to_bytes t.buf
   in
   Unix.sendto t.sock_fd dgram 0 (Bytes.length dgram) [] t.dest |> ignore

lib/logging/pretty.ml

@@ -95,7 +95,7 @@ let writer t ~ts ~ns ~lvl msg =
   let f mask = t.flags land mask = mask in
   let align bp =
     let n = t.align_to - Buffer.length bp in
-    t.align_to <- Buffer.length bp;
+    t.align_to <- max t.align_to (Buffer.length bp);
     n
   in
   let indent bp =