Run jobs with 'set -e' so that they exit on error.

[whenjobs.git] / daemon / daemon.ml

diff --git a/daemon/daemon.ml b/daemon/daemon.ml
index fd986fb..6ccfcce 100644 (file)
--- a/daemon/daemon.ml
+++ b/daemon/daemon.ml
@@ -18,6 +18,7 @@
 
 open Whenutils
 
+open Big_int
 open Unix
 open Printf
 
@@ -80,7 +81,12 @@ let rec init j d =
   );
 
   (* Handle SIGCHLD to clean up jobs. *)
-  Sys.set_signal Sys.sigchld (Sys.Signal_handle handle_sigchld)
+  Sys.set_signal Sys.sigchld (Sys.Signal_handle handle_sigchld);
+
+  (* Initialize the variables.  XXX Eventually this will be saved
+   * and loaded from a persistent store.
+   *)
+  variables := StringMap.add "JOBSERIAL" (T_int zero_big_int) !variables
 
 and proc_reload_file () =
   if !debug then Syslog.notice "remote call: reload_file";
@@ -91,12 +97,35 @@ and proc_reload_file () =
 and proc_set_variable (name, value) =
   if !debug then Syslog.notice "remote call: set_variable %s" name;
 
-  let value = variable_of_rpc value in
-  variables := StringMap.add name value !variables;
+  try
+    (* Don't permit certain names. *)
+    if name = "JOBSERIAL" then
+      failwith "JOBSERIAL variable cannot be set";
+
+    let len = String.length name in
+    if len = 0 then
+      failwith "variable name is an empty string";
+    if name.[0] <> '_' && not (isalpha name.[0]) then
+      failwith "variable name must start with alphabetic character or underscore";
+
+    let rec loop i =
+      if i >= len then ()
+      else if name.[i] <> '_' && not (isalnum name.[i]) then
+        failwith "variable name contains non-alphanumeric non-underscore character"
+      else loop (i+1)
+    in
+    loop 1;
+
+    let value = variable_of_rpc value in
+    variables := StringMap.add name value !variables;
+
+    (* Which jobs need to be re-evaluated? *)
+    let jobnames = try StringMap.find name !dependencies with Not_found -> [] in
+    reevaluate_whenjobs jobnames;
 
-  (* Which jobs need to be re-evaluated? *)
-  let jobnames = try StringMap.find name !dependencies with Not_found -> [] in
-  reevaluate_whenjobs jobnames
+    `ok
+  with
+    Failure msg -> `error msg
 
 and proc_get_variable name =
   if !debug then Syslog.notice "remote call: get_variable %s" name;
@@ -169,7 +198,7 @@ and reload_file () =
     dependencies := map in
 
   (* Re-evaluate all when jobs. *)
-  reevaluate_whenjobs (StringMap.keys !jobs);
+  reevaluate_whenjobs ~onload:true (StringMap.keys !jobs);
 
   (* Schedule the next every job to run. *)
   schedule_next_everyjob ()
@@ -178,7 +207,7 @@ and reload_file () =
  * a fixpoint.  Run those that need to be run.  every-statement jobs
  * are ignored here.
  *)
-and reevaluate_whenjobs jobnames =
+and reevaluate_whenjobs ?(onload=false) jobnames =
   let rec loop set jobnames =
     let set' =
       List.fold_left (
@@ -189,7 +218,7 @@ and reevaluate_whenjobs jobnames =
           assert (jobname = job.job_name);
 
           let r, job' =
-            try job_evaluate job !variables
+            try job_evaluate job !variables onload
             with Invalid_argument err | Failure err ->
               Syslog.error "error evaluating job %s (at %s): %s"
                 jobname (Camlp4.PreCast.Ast.Loc.to_string job.job_loc) err;
@@ -210,7 +239,7 @@ and reevaluate_whenjobs jobnames =
   let set = loop StringSet.empty jobnames in
   let jobnames = StringSet.elements set in
   (* Ensure the jobs always run in predictable (name) order. *)
-  let jobnames = List.sort compare jobnames in
+  let jobnames = List.sort compare_jobnames jobnames in
   List.iter run_job
     (List.map (fun jobname -> StringMap.find jobname !jobs) jobnames)
 
@@ -263,7 +292,8 @@ and schedule_next_everyjob () =
     if jobs <> [] then (
       (* Ensure the jobs always run in predictable (name) order. *)
       let jobs =
-        List.sort (fun { job_name = a } { job_name = b } -> compare a b) jobs in
+        List.sort (fun {job_name = a} {job_name = b} -> compare_jobnames a b)
+          jobs in
 
       if !debug then
         Syslog.notice "scheduling job(s) %s to run at %s"
@@ -290,7 +320,18 @@ and string_of_time_t t =
     tm.tm_hour tm.tm_min tm.tm_sec
 
 and run_job job =
-  Syslog.notice "running %s" job.job_name;
+  let () =
+    (* Increment JOBSERIAL. *)
+    let serial =
+      match StringMap.find "JOBSERIAL" !variables with
+      | T_int serial ->
+        let serial = succ_big_int serial in
+        variables := StringMap.add "JOBSERIAL" (T_int serial) !variables;
+        serial
+      | _ -> assert false in
+
+    Syslog.notice "running %s (JOBSERIAL=%s)"
+      job.job_name (string_of_big_int serial) in
 
   (* Create a temporary directory.  The current directory of the job
    * will be in this directory.  The directory is removed when the
@@ -312,12 +353,15 @@ and run_job job =
     (* Create a temporary file containing the shell script fragment. *)
     let script = dir // "script" in
     let chan = open_out script in
+    fprintf chan "set -e\n"; (* So that jobs exit on error. *)
     output_string chan job.job_script.sh_script;
     close_out chan;
     chmod script 0o700;
 
+    let shell = try getenv "SHELL" with Not_found -> "/bin/sh" in
+
     (* Execute the shell script. *)
-    (try execvp "bash" [| "bash"; "-c"; script |];
+    (try execvp shell [| shell; "-c"; script |];
      with Unix_error (err, fn, _) ->
        Syslog.error "%s failed: %s: %s" fn script (error_message err)
     );
@@ -356,5 +400,21 @@ and cleanup_job job dir =
   let cmd = sprintf "rm -rf '%s'" dir in
   ignore (Sys.command cmd)
 
+(* Intelligent comparison of job names. *)
+and compare_jobnames name1 name2 =
+  try
+    let len1 = String.length name1
+    and len2 = String.length name2 in
+    if len1 > 4 && len2 > 4 &&
+      String.sub name1 0 4 = "job$" && String.sub name2 0 4 = "job$"
+    then (
+      let i1 = int_of_string (String.sub name1 4 (len1-4)) in
+      let i2 = int_of_string (String.sub name2 4 (len2-4)) in
+      compare i1 i2
+    )
+    else raise Not_found
+  with _ ->
+    compare name1 name2
+
 let main_loop () =
   Unixqueue.run esys