Mailing List Archive

commit fd1c70442d3aa962be4d041d5f8fce9d2fa72ce1
Author: Edwin Török <edvin.torok@citrix.com>
AuthorDate: Tue May 11 15:56:50 2021 +0000
Commit: Andrew Cooper <andrew.cooper3@citrix.com>
CommitDate: Thu Feb 9 15:58:51 2023 +0000

tools/oxenstored: validate config file before live update

The configuration file can contain typos or various errors that could prevent
live update from succeeding (e.g. a flag only valid on a different version).
Unknown entries in the config file would be ignored on startup normally,
add a strict --config-test that live-update can use to check that the config file
is valid *for the new binary*.

For compatibility with running old code during live update recognize
--live --help as an equivalent to --config-test.

Signed-off-by: Edwin Török <edvin.torok@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
(cherry picked from commit e6f07052ce4a0f0b7d4dc522d87465efb2d9ee86)
---
tools/ocaml/xenstored/parse_arg.ml | 26 ++++++++++++++++++++++++++
tools/ocaml/xenstored/xenstored.ml | 11 +++++++++--
2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/tools/ocaml/xenstored/parse_arg.ml b/tools/ocaml/xenstored/parse_arg.ml
index 7c0478e76a..5e4ca6f1f7 100644
--- a/tools/ocaml/xenstored/parse_arg.ml
+++ b/tools/ocaml/xenstored/parse_arg.ml
@@ -26,8 +26,14 @@ type config =
restart: bool;
live_reload: bool;
disable_socket: bool;
+ config_test: bool;
}

+let get_config_filename config_file =
+ match config_file with
+ | Some name -> name
+ | None -> Define.default_config_dir ^ "/oxenstored.conf"
+
let do_argv =
let pidfile = ref "" and tracefile = ref "" (* old xenstored compatibility *)
and domain_init = ref true
@@ -38,6 +44,8 @@ let do_argv =
and restart = ref false
and live_reload = ref false
and disable_socket = ref false
+ and config_test = ref false
+ and help = ref false
in

let speclist =
@@ -55,10 +63,27 @@ let do_argv =
("-T", Arg.Set_string tracefile, ""); (* for compatibility *)
("--restart", Arg.Set restart, "Read database on starting");
("--live", Arg.Set live_reload, "Read live dump on startup");
+ ("--config-test", Arg.Set config_test, "Test validity of config file");
("--disable-socket", Arg.Unit (fun () -> disable_socket := true), "Disable socket");
+ ("--help", Arg.Set help, "Display this list of options")
] in
let usage_msg = "usage : xenstored [--config-file <filename>] [--no-domain-init] [--help] [--no-fork] [--reraise-top-level] [--restart] [--disable-socket]" in
Arg.parse speclist (fun _ -> ()) usage_msg;
+ let () =
+ if !help then begin
+ if !live_reload then
+ (*
+ * Transform --live --help into --config-test for backward compat with
+ * running code during live update.
+ * Caller will validate config and exit
+ *)
+ config_test := true
+ else begin
+ Arg.usage_string speclist usage_msg |> print_endline;
+ exit 0
+ end
+ end
+ in
{
domain_init = !domain_init;
activate_access_log = !activate_access_log;
@@ -70,4 +95,5 @@ let do_argv =
restart = !restart;
live_reload = !live_reload;
disable_socket = !disable_socket;
+ config_test = !config_test;
}
diff --git a/tools/ocaml/xenstored/xenstored.ml b/tools/ocaml/xenstored/xenstored.ml
index 4d5851c5cb..e2638a5af2 100644
--- a/tools/ocaml/xenstored/xenstored.ml
+++ b/tools/ocaml/xenstored/xenstored.ml
@@ -88,7 +88,7 @@ let default_pidfile = Paths.xen_run_dir ^ "/xenstored.pid"

let ring_scan_interval = ref 20

-let parse_config filename =
+let parse_config ?(strict=false) filename =
let pidfile = ref default_pidfile in
let options = [.
("merge-activate", Config.Set_bool Transaction.do_coalesce);
@@ -129,11 +129,12 @@ let parse_config filename =
("xenstored-port", Config.Set_string Domains.xenstored_port); ] in
begin try Config.read filename options (fun _ _ -> raise Not_found)
with
- | Config.Error err -> List.iter (fun (k, e) ->
+ | Config.Error err as e -> List.iter (fun (k, e) ->
match e with
| "unknown key" -> eprintf "config: unknown key %s\n" k
| _ -> eprintf "config: %s: %s\n" k e
) err;
+ if strict then raise e
| Sys_error m -> eprintf "error: config: %s\n" m;
end;
!pidfile
@@ -358,6 +359,12 @@ let tweak_gc () =
let () =
Printexc.set_uncaught_exception_handler Logging.fallback_exception_handler;
let cf = do_argv in
+ if cf.config_test then begin
+ let path = config_filename cf in
+ let _pidfile:string = parse_config ~strict:true path in
+ Printf.printf "Configuration valid at %s\n%!" path;
+ exit 0
+ end;
let pidfile =
if Sys.file_exists (config_filename cf) then
parse_config (config_filename cf)
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.16