*)
open Whenutils
+open Whenexpr
+open Big_int
open Unix
open Printf
-(* All jobs that are loaded. Maps name -> [job] structure. *)
-let jobs = ref StringMap.empty
+(* See [exit.c]. *)
+external _exit : int -> 'a = "whenjobs__exit"
-(* Map variable names to jobs which depend on that variable. This
- * gives us a quick way to tell which jobs might need to be reevaluated
- * when a variable is set.
- *)
-let dependencies = ref StringMap.empty
+(* $HOME/.whenjobs *)
+let jobsdir = ref ""
-(* Current values of variables. Using the referentially transparent
- * type Map is very useful here because it lets us cheaply keep
- * previous values of variables.
- *)
-let variables : variables ref = ref StringMap.empty
+(* The state. *)
+let state = ref Whenstate.empty
-(* Last time that an every job ran. See schedule_next_everyjob below. *)
-let last_t = ref (time ())
+(* Jobs that are running: a map of PID -> (job, tmpdir, serial, start_time).
+ * Note that the job may no longer exist *OR* it may have been renamed,
+ * eg. if the jobs file was reloaded.
+ *)
+let runningmap = ref IntMap.empty
-(* $HOME/.whenjobs *)
-let jobsdir = ref ""
+(* Serial numbers of running jobs. Map of serial -> PID (in runningmap). *)
+let serialmap = ref BigIntMap.empty
(* Was debugging requested on the command line? *)
let debug = ref false
+(* The server. *)
+let server = ref None
+
let esys = Unixqueue.standard_event_system ()
+
+(* The timer. It's convenient to have this as a global variable
+ * because (a) there should only be one timer (which fires when the
+ * soonest every-job becomes ready), and (b) it's complicated to track
+ * that timer and avoid it getting double-scheduled (eg. when we
+ * reload the jobs file) without having a global variable.
+ *)
let timer_group = ref None
let rec init j d =
let addr = sprintf "%s/socket" !jobsdir in
(try unlink addr with Unix_error _ -> ());
- ignore (
+ (* Create the Unix domain socket server. *)
+ server := Some (
Whenproto_srv.When.V1.create_server
~proc_reload_file
~proc_set_variable
~proc_get_variable
~proc_get_variable_names
+ ~proc_exit_daemon
+ ~proc_get_jobs
+ ~proc_cancel_job
+ ~proc_start_job
+ ~proc_get_job
+ ~proc_set_variables
+ ~proc_get_job_names
+ ~proc_test_variables
+ ~proc_ping_daemon
(Rpc_server.Unix addr)
Rpc.Tcp (* not TCP, this is the same as SOCK_STREAM *)
Rpc.Socket
esys
- )
+ );
+
+ (* Handle SIGCHLD to clean up jobs. *)
+ Sys.set_signal Sys.sigchld (Sys.Signal_handle handle_sigchld);
+
+ (* Initialize the variables. *)
+ state := Whenstate.set_variable !state "JOBSERIAL" (T_int zero_big_int)
and proc_reload_file () =
if !debug then Syslog.notice "remote call: 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
+ check_valid_variable_name name;
+
+ let value = variable_of_rpc value in
+ state := Whenstate.set_variable !state name value;
- (* 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 jobs = Whenstate.get_dependencies !state [name] in
+ let jobnames, state' = reevaluate_whenjobs !state jobs in
+ let state' = run_whenjobs state' jobnames in
+ state := state';
+
+ `ok
+ with
+ Failure msg -> `error msg
and proc_get_variable name =
if !debug then Syslog.notice "remote call: get_variable %s" name;
- try rpc_of_variable (StringMap.find name !variables)
- with (* all non-existent variables are empty strings *)
- Not_found -> `string_t ""
+ rpc_of_variable (Whenstate.get_variable !state name)
and proc_get_variable_names () =
if !debug then Syslog.notice "remote call: get_variable_names";
- (* Only return variables that are non-empty. *)
- let vars = StringMap.fold (
- fun name value xs -> if value <> T_string "" then name :: xs else xs
- ) !variables [] in
+ let vars = Whenstate.get_variable_names !state in
+
+ (* Return variable names as a sorted array. *)
let vars = Array.of_list vars in
Array.sort compare vars;
vars
+and proc_exit_daemon () =
+ if !debug then Syslog.notice "remote call: exit_daemon";
+
+ match !server with
+ | None ->
+ `error "exit_daemon: no server handle"
+ | Some s ->
+ Rpc_server.stop_server ~graceful:true s;
+ server := None;
+ `ok
+
+and proc_get_jobs () =
+ let running = Array.of_list (IntMap.values !runningmap) in
+ Array.map (
+ fun (job, dir, serial, start_time) ->
+ { Whenproto_aux.job_name = job.job_name;
+ job_serial = string_of_big_int serial;
+ job_tmpdir = dir; job_start_time = Int64.of_float start_time }
+ ) running
+
+and proc_cancel_job serial =
+ try
+ let serial = big_int_of_string serial in
+ let pid = BigIntMap.find serial !serialmap in
+ kill pid 15;
+ `ok
+ with
+ | Not_found -> `error "job not found"
+ | exn -> `error (Printexc.to_string exn)
+
+and proc_start_job jobname =
+ try
+ let job = Whenstate.get_job !state jobname in
+ let state' = run_job !state job in
+ state := state';
+ `ok
+ with
+ | Not_found -> `error "job not found"
+ | exn -> `error (Printexc.to_string exn)
+
+and proc_get_job serial =
+ try
+ let serial = big_int_of_string serial in
+ let pid = BigIntMap.find serial !serialmap in
+ let job, dir, serial, start_time = IntMap.find pid !runningmap in
+ { Whenproto_aux.job_name = job.job_name;
+ job_serial = string_of_big_int serial;
+ job_tmpdir = dir; job_start_time = Int64.of_float start_time }
+ with
+ | Not_found -> failwith "job not found"
+ | exn -> failwith (Printexc.to_string exn)
+
+and proc_set_variables vars =
+ try
+ let vars = Array.map (
+ fun { Whenproto_aux.sv_name = name; sv_value = value } ->
+ name, variable_of_rpc value
+ ) vars in
+ let vars = Array.to_list vars in
+
+ if !debug then
+ Syslog.notice "remote call: set_variables (%s)"
+ (String.concat " "
+ (List.map (
+ fun (name, value) ->
+ sprintf "%s=%s" name (string_of_variable value)
+ ) vars));
+
+ List.iter (fun (name, _) -> check_valid_variable_name name) vars;
+
+ (* Update all the variables atomically. *)
+ let s = List.fold_left (
+ fun s (name, value) -> Whenstate.set_variable s name value
+ ) !state vars in
+ state := s;
+
+ (* Which jobs need to be re-evaluated? *)
+ let jobs = Whenstate.get_dependencies !state (List.map fst vars) in
+ let jobnames, state' = reevaluate_whenjobs !state jobs in
+ let state' = run_whenjobs state' jobnames in
+ state := state';
+
+ `ok
+ with
+ Failure msg -> `error msg
+
+and proc_get_job_names () =
+ Array.of_list (Whenstate.get_job_names !state)
+
+and proc_test_variables vars =
+ (* This is the same as proc_set_variables, except that it doesn't
+ * update the state, it just returns the jobs that *would* run if
+ * these variables were set to these values.
+ *)
+ let vars = Array.map (
+ fun { Whenproto_aux.sv_name = name; sv_value = value } ->
+ name, variable_of_rpc value
+ ) vars in
+ let vars = Array.to_list vars in
+
+ if !debug then
+ Syslog.notice "remote call: test_variables (%s)"
+ (String.concat " "
+ (List.map (
+ fun (name, value) ->
+ sprintf "%s=%s" name (string_of_variable value)
+ ) vars));
+
+ List.iter (fun (name, _) -> check_valid_variable_name name) vars;
+
+ (* Update all the variables atomically. *)
+ let state = List.fold_left (
+ fun s (name, value) -> Whenstate.set_variable s name value
+ ) !state vars in
+
+ (* Which jobs WOULD be re-evaluated? *)
+ let jobs = Whenstate.get_dependencies state (List.map fst vars) in
+ let jobnames, _ = reevaluate_whenjobs state jobs in
+
+ (* Return the names. *)
+ Array.of_list jobnames
+
+and proc_ping_daemon () = `ok
+
(* Reload the jobs file. *)
and reload_file () =
let file = sprintf "%s/jobs.cmo" !jobsdir in
- Whenfile.init ();
- let js =
+ (* As we are reloading the file, we want to create a new state
+ * that has no jobs, but has all the variables from the previous
+ * state.
+ *)
+ let s = Whenstate.copy_variables !state Whenstate.empty in
+ Whenfile.init s;
+
+ let s =
try
Dynlink.loadfile file;
- let jobs = Whenfile.get_jobs () in
- Syslog.notice "loaded %d job(s) from %s" (List.length jobs) file;
- jobs
+ let s = Whenfile.get_state () in
+ Syslog.notice "loaded %d job(s) from %s" (Whenstate.nr_jobs s) file;
+ s
with
| Dynlink.Error err ->
let err = Dynlink.error_message err in
| exn ->
failwith (Printexc.to_string exn) in
- (* Set 'jobs' and related global variables. *)
- let () =
- let map = List.fold_left (
- fun map j ->
- let name = j.job_name in
- StringMap.add name j map
- ) StringMap.empty js in
- jobs := map in
-
- let () =
- let map = List.fold_left (
- fun map j ->
- let deps = dependencies_of_job j in
- let name = j.job_name in
- List.fold_left (
- fun map d ->
- let names = try StringMap.find d map with Not_found -> [] in
- StringMap.add d (name :: names) map
- ) map deps
- ) StringMap.empty js in
- dependencies := map in
+ let s = Whenstate.copy_prev_state !state s in
+ state := s;
(* Re-evaluate all when jobs. *)
- reevaluate_whenjobs (StringMap.keys !jobs);
+ let jobs = Whenstate.get_whenjobs !state in
+ let jobnames, state' = reevaluate_whenjobs ~onload:true !state jobs in
+ let state' = run_whenjobs state' jobnames in
+ state := state';
(* Schedule the next every job to run. *)
- last_t := time ();
schedule_next_everyjob ()
-(* Re-evaluate each named when-statement job, in a loop until we reach
- * a fixpoint. Run those that need to be run. every-statement jobs
- * are ignored here.
+(* Re-evaluate each when-statement job, in a loop until we reach
+ * a fixpoint. Return the list of job names that should run and
+ * the updated state.
*)
-and reevaluate_whenjobs jobnames =
- let rec loop set jobnames =
- let set' =
+and reevaluate_whenjobs ?onload state jobs =
+ let rec loop (set, state) jobs =
+ let set', state' =
List.fold_left (
- fun set jobname ->
- let job =
- try StringMap.find jobname !jobs
- with Not_found -> assert false in
- assert (jobname = job.job_name);
-
- let r, job' = job_evaluate job !variables in
- jobs := StringMap.add jobname job' !jobs;
+ fun (set, state) job ->
+ let r, state' =
+ try Whenstate.evaluate_whenjob ?onload state job
+ with Invalid_argument err | Failure err ->
+ Syslog.error "error evaluating job %s (at %s): %s"
+ job.job_name (Camlp4.PreCast.Ast.Loc.to_string job.job_loc) err;
+ false, state in
if !debug then
- Syslog.notice "evaluate %s -> %b\n" jobname r;
+ Syslog.notice "evaluate %s -> %b\n" job.job_name r;
- if r then StringSet.add jobname set else set
- ) set jobnames in
+ (if r then StringSet.add job.job_name set else set), state'
+ ) (set, state) jobs in
+ (* reached a fixpoint? *)
if StringSet.compare set set' <> 0 then
- loop set' jobnames
+ loop (set', state') jobs
else
- set'
+ (set', state')
in
- let set = loop StringSet.empty jobnames in
+ let set, state = loop (StringSet.empty, state) jobs in
let jobnames = StringSet.elements set in
+
(* Ensure the jobs always run in predictable (name) order. *)
- let jobnames = List.sort compare jobnames in
- List.iter run_job
- (List.map (fun jobname -> StringMap.find jobname !jobs) jobnames)
+ let jobnames = List.sort compare_jobnames jobnames in
+ jobnames, state
+
+and run_whenjobs state jobnames =
+ (* Run the jobs. *)
+ let jobs = List.map (Whenstate.get_job state) jobnames in
+ List.fold_left run_job state jobs
(* Schedule the next every-statement job to run, if there is one. We
* look at the every jobs, work out the time that each must run at,
* pick the job(s) which must run soonest, and schedule a timer to run
- * them. When the timer fires, it runs those jobs, then call this
- * function again. 'last_t' is the base time used for scheduling (or
- * the time that the file was last reloaded).
+ * them. When the timer fires, it runs those jobs, then calls this
+ * function again.
*)
and schedule_next_everyjob () =
+ let t = time () in
+
(* Get only everyjobs. *)
- let jobs = StringMap.values !jobs in
- let jobs = filter_map (
+ let jobs = Whenstate.get_everyjobs !state in
+ let jobs = List.map (
function
- | { job_cond = Every_job period } as job -> Some (job, period)
- | { job_cond = When_job _ } -> None
+ | { job_cond = Every_job period } as job -> (job, period)
+ | { job_cond = When_job _ } -> assert false
) jobs in
(* Map everyjob to next time it must run. *)
let jobs = List.map (
fun (job, period) ->
- let t' = next_periodexpr !last_t period in
- assert (t' > !last_t); (* serious bug in next_periodexpr if false *)
+ let t' = next_periodexpr t period in
+ assert (t' > t); (* serious bug in next_periodexpr if false *)
job, t'
) jobs in
let t, jobs = pick jobs in
if t > 0. then (
- last_t := t;
-
if jobs <> [] then (
+ (* Ensure the jobs always run in predictable (name) order. *)
+ let jobs =
+ 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"
(String.concat ", " (List.map (fun { job_name = name } -> name) jobs))
(* Schedule them to run at time t. *)
let g = new_timer_group () in
- let w = Unixqueue.new_wait_id esys in
let t_diff = t -. Unix.time () in
let t_diff = if t_diff < 0. then 0. else t_diff in
- Unixqueue.add_resource esys g (Unixqueue.Wait w, t_diff);
- let run_jobs _ _ _ =
- List.iter run_job jobs;
- delete_timer ();
- schedule_next_everyjob ();
+ let run_jobs () =
+ delete_timer_group (); (* Delete the timer. *)
+ let state' = List.fold_left run_job !state jobs in
+ state := state';
+ schedule_next_everyjob ()
in
- Unixqueue.add_handler esys g run_jobs;
+ Unixqueue.weak_once esys g t_diff run_jobs;
)
)
-and string_of_time_t t =
- let tm = gmtime t in
- sprintf "%04d-%02d-%02d %02d:%02d:%02d UTC"
- (1900+tm.tm_year) (1+tm.tm_mon) tm.tm_mday
- tm.tm_hour tm.tm_min tm.tm_sec
-
and new_timer_group () =
- delete_timer ();
+ delete_timer_group ();
let g = Unixqueue.new_group esys in
timer_group := Some g;
g
-and delete_timer () =
+and delete_timer_group () =
match !timer_group with
| None -> ()
| Some g ->
Unixqueue.clear esys g;
timer_group := None
-and run_job job =
- Syslog.notice "running %s" job.job_name;
- () (* XXX *)
+and run_job state job =
+ (* Increment JOBSERIAL. *)
+ let serial, state =
+ match Whenstate.get_variable state "JOBSERIAL" with
+ | T_int serial ->
+ let serial = succ_big_int serial in
+ let state' = Whenstate.set_variable state "JOBSERIAL" (T_int serial) in
+ serial, state'
+ | _ -> assert false in
+
+ (* Call the pre-condition script. Note this may decide not to run
+ * the job by returning false.
+ *)
+ let pre_condition () =
+ match job.job_pre with
+ | None -> true
+ | Some pre ->
+ let rs = ref [] in
+ IntMap.iter (
+ fun pid (job, _, serial, start_time) ->
+ let r = { pirun_job_name = job.job_name;
+ pirun_serial = serial;
+ pirun_start_time = start_time;
+ pirun_pid = pid } in
+ rs := r :: !rs
+ ) !runningmap;
+ let preinfo = {
+ pi_job_name = job.job_name;
+ pi_serial = serial;
+ pi_variables = Whenstate.get_variables state;
+ pi_running = !rs;
+ } in
+ pre preinfo
+ in
+ if pre_condition () then (
+ Syslog.notice "running %s (JOBSERIAL=%s)"
+ job.job_name (string_of_big_int serial);
+
+ (* Create a temporary directory. The current directory of the job
+ * will be in this directory. The directory is removed when the
+ * child process exits.
+ *)
+ let dir = tmpdir () in
+
+ let pid = fork () in
+ if pid = 0 then ( (* child process running the job *)
+ chdir dir;
+
+ (* Set environment variables corresponding to each variable. *)
+ List.iter
+ (fun (name, value) -> putenv name (string_of_variable value))
+ (Whenstate.get_variables state);
+
+ (* Set the $JOBNAME environment variable. *)
+ putenv "JOBNAME" job.job_name;
+
+ (* Create a temporary file containing the shell script fragment. *)
+ let script = dir // "script.sh" 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
+
+ (* Set output to file. *)
+ let output = dir // "output.txt" in
+ let fd = openfile output [O_WRONLY; O_CREAT; O_TRUNC; O_NOCTTY] 0o600 in
+ dup2 fd stdout;
+ dup2 fd stderr;
+ close fd;
+
+ (* Execute the shell script. *)
+ (try execvp shell [| shell; "-c"; script |];
+ with Unix_error (err, fn, _) ->
+ Syslog.error "%s failed: %s: %s" fn script (error_message err)
+ );
+ _exit 1
+ );
+
+ (* Remember this PID, the job and the temporary directory, so we
+ * can clean up when the child exits.
+ *)
+ runningmap := IntMap.add pid (job, dir, serial, time ()) !runningmap;
+ serialmap := BigIntMap.add serial pid !serialmap;
+
+ state
+ )
+ else (
+ Syslog.notice "not running %s (JOBSERIAL=%s) because pre() condition returned false"
+ job.job_name (string_of_big_int serial);
+
+ state
+ )
+
+and tmpdir () =
+ let chan = open_in "/dev/urandom" in
+ let data = String.create 16 in
+ really_input chan data 0 (String.length data);
+ close_in chan;
+ let data = Digest.to_hex (Digest.string data) in
+ let dir = Filename.temp_dir_name // sprintf "whenjobs%s" data in
+ mkdir dir 0o700;
+ dir
+
+(* This is called when a job (child process) exits. *)
+and handle_sigchld _ =
+ try
+ let pid, status = waitpid [WNOHANG] 0 in
+ if pid > 0 then (
+ (* Look up the PID in the running jobs map. *)
+ let job, dir, serial, time = IntMap.find pid !runningmap in
+ runningmap := IntMap.remove pid !runningmap;
+ serialmap := BigIntMap.remove serial !serialmap;
+ post_job job dir serial time status
+ )
+ with Unix_error _ | Not_found -> ()
+
+and post_job job dir serial time status =
+ (* If there is a post function, run it. *)
+ (match job.job_post with
+ | None -> ()
+ | Some post ->
+ let code =
+ match status with
+ | WEXITED c -> c
+ | WSIGNALED s | WSTOPPED s -> 1 in
+ let result = {
+ res_job_name = job.job_name;
+ res_serial = serial;
+ res_code = code;
+ res_tmpdir = dir;
+ res_output = dir // "output.txt";
+ res_start_time = time
+ } in
+ try post result
+ with
+ | Failure msg ->
+ Syslog.error "job %s post function failed: %s" job.job_name msg
+ | exn ->
+ Syslog.error "job %s post function exception: %s"
+ job.job_name (Printexc.to_string exn)
+ );
+
+ (* This should be safe because the path cannot contain shell metachars. *)
+ 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