2 * Copyright (C) 2012 Red Hat Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
26 external _exit : int -> 'a = "whenjobs__exit"
28 (* All jobs that are loaded. Maps name -> [job] structure. *)
29 let jobs = ref StringMap.empty
31 (* Map variable names to jobs which depend on that variable. This
32 * gives us a quick way to tell which jobs might need to be reevaluated
33 * when a variable is set.
35 let dependencies = ref StringMap.empty
37 (* Current values of variables. Using the referentially transparent
38 * type Map is very useful here because it lets us cheaply keep
39 * previous values of variables.
41 let variables : variables ref = ref StringMap.empty
46 (* Jobs that are running; map of PID -> (job, other data). Note that
47 * the job may no longer exist *OR* it may have been renamed,
48 * eg. if the jobs file was reloaded.
50 let running = ref IntMap.empty
52 (* Was debugging requested on the command line? *)
58 let esys = Unixqueue.standard_event_system ()
60 (* The timer. It's convenient to have this as a global variable
61 * because (a) there should only be one timer (which fires when the
62 * soonest every-job becomes ready), and (b) it's complicated to track
63 * that timer and avoid it getting double-scheduled (eg. when we
64 * reload the jobs file) without having a global variable.
66 let timer_group = ref None
72 Whenlock.create_lock !jobsdir;
74 (* Remove old socket if it exists. *)
75 let addr = sprintf "%s/socket" !jobsdir in
76 (try unlink addr with Unix_error _ -> ());
79 Whenproto_srv.When.V1.create_server
83 ~proc_get_variable_names
85 (Rpc_server.Unix addr)
86 Rpc.Tcp (* not TCP, this is the same as SOCK_STREAM *)
91 (* Handle SIGCHLD to clean up jobs. *)
92 Sys.set_signal Sys.sigchld (Sys.Signal_handle handle_sigchld);
94 (* Initialize the variables. XXX Eventually this will be saved
95 * and loaded from a persistent store.
97 variables := StringMap.add "JOBSERIAL" (T_int zero_big_int) !variables
99 and proc_reload_file () =
100 if !debug then Syslog.notice "remote call: reload_file";
102 try reload_file (); `ok
103 with Failure err -> `error err
105 and proc_set_variable (name, value) =
106 if !debug then Syslog.notice "remote call: set_variable %s" name;
109 (* Don't permit certain names. *)
110 if name = "JOBSERIAL" then
111 failwith "JOBSERIAL variable cannot be set";
113 let len = String.length name in
115 failwith "variable name is an empty string";
116 if name.[0] <> '_' && not (isalpha name.[0]) then
117 failwith "variable name must start with alphabetic character or underscore";
121 else if name.[i] <> '_' && not (isalnum name.[i]) then
122 failwith "variable name contains non-alphanumeric non-underscore character"
127 let value = variable_of_rpc value in
128 variables := StringMap.add name value !variables;
130 (* Which jobs need to be re-evaluated? *)
131 let jobnames = try StringMap.find name !dependencies with Not_found -> [] in
132 reevaluate_whenjobs jobnames;
136 Failure msg -> `error msg
138 and proc_get_variable name =
139 if !debug then Syslog.notice "remote call: get_variable %s" name;
141 try rpc_of_variable (StringMap.find name !variables)
142 with (* all non-existent variables are empty strings *)
143 Not_found -> `string_t ""
145 and proc_get_variable_names () =
146 if !debug then Syslog.notice "remote call: get_variable_names";
148 (* Only return variables that are non-empty. *)
149 let vars = StringMap.fold (
150 fun name value xs -> if value <> T_string "" then name :: xs else xs
152 let vars = Array.of_list vars in
153 Array.sort compare vars;
156 and proc_exit_daemon () =
157 if !debug then Syslog.notice "remote call: exit_daemon";
161 `error "exit_daemon: no server handle"
163 Rpc_server.stop_server ~graceful:true s;
167 (* Reload the jobs file. *)
169 let file = sprintf "%s/jobs.cmo" !jobsdir in
174 Dynlink.loadfile file;
175 let jobs = Whenfile.get_jobs () in
176 Syslog.notice "loaded %d job(s) from %s" (List.length jobs) file;
179 | Dynlink.Error err ->
180 let err = Dynlink.error_message err in
181 Syslog.error "error loading jobs: %s" err;
184 failwith (Printexc.to_string exn) in
186 (* Set 'jobs' and related global variables. *)
188 let map = List.fold_left (
190 let name = j.job_name in
191 StringMap.add name j map
192 ) StringMap.empty js in
196 let map = List.fold_left (
198 let deps = dependencies_of_job j in
199 let name = j.job_name in
202 let names = try StringMap.find d map with Not_found -> [] in
203 StringMap.add d (name :: names) map
205 ) StringMap.empty js in
206 dependencies := map in
208 (* Re-evaluate all when jobs. *)
209 reevaluate_whenjobs ~onload:true (StringMap.keys !jobs);
211 (* Schedule the next every job to run. *)
212 schedule_next_everyjob ()
214 (* Re-evaluate each named when-statement job, in a loop until we reach
215 * a fixpoint. Run those that need to be run. every-statement jobs
218 and reevaluate_whenjobs ?(onload=false) jobnames =
219 let rec loop set jobnames =
224 try StringMap.find jobname !jobs
225 with Not_found -> assert false in
226 assert (jobname = job.job_name);
229 try job_evaluate job !variables onload
230 with Invalid_argument err | Failure err ->
231 Syslog.error "error evaluating job %s (at %s): %s"
232 jobname (Camlp4.PreCast.Ast.Loc.to_string job.job_loc) err;
235 jobs := StringMap.add jobname job' !jobs;
238 Syslog.notice "evaluate %s -> %b\n" jobname r;
240 if r then StringSet.add jobname set else set
242 if StringSet.compare set set' <> 0 then
247 let set = loop StringSet.empty jobnames in
248 let jobnames = StringSet.elements set in
249 (* Ensure the jobs always run in predictable (name) order. *)
250 let jobnames = List.sort compare_jobnames jobnames in
252 (List.map (fun jobname -> StringMap.find jobname !jobs) jobnames)
254 (* Schedule the next every-statement job to run, if there is one. We
255 * look at the every jobs, work out the time that each must run at,
256 * pick the job(s) which must run soonest, and schedule a timer to run
257 * them. When the timer fires, it runs those jobs, then calls this
260 and schedule_next_everyjob () =
263 (* Get only everyjobs. *)
264 let jobs = StringMap.values !jobs in
265 let jobs = filter_map (
267 | { job_cond = Every_job period } as job -> Some (job, period)
268 | { job_cond = When_job _ } -> None
271 (* Map everyjob to next time it must run. *)
272 let jobs = List.map (
274 let t' = next_periodexpr t period in
275 assert (t' > t); (* serious bug in next_periodexpr if false *)
279 (* Sort, soonest first. *)
280 let jobs = List.sort (fun (_,a) (_,b) -> compare a b) jobs in
285 Syslog.notice "%s: next scheduled run at %s"
286 job.job_name (string_of_time_t t)
290 (* Pick the job(s) which run soonest. *)
291 let rec pick = function
294 | (j1, t) :: (j2, t') :: _ when t < t' -> t, [j1]
295 | (j1, t) :: (((j2, t') :: _) as rest) -> t, (j1 :: snd (pick rest))
297 let t, jobs = pick jobs in
301 (* Ensure the jobs always run in predictable (name) order. *)
303 List.sort (fun {job_name = a} {job_name = b} -> compare_jobnames a b)
307 Syslog.notice "scheduling job(s) %s to run at %s"
308 (String.concat ", " (List.map (fun { job_name = name } -> name) jobs))
309 (string_of_time_t t);
311 (* Schedule them to run at time t. *)
312 let g = new_timer_group () in
313 let t_diff = t -. Unix.time () in
314 let t_diff = if t_diff < 0. then 0. else t_diff in
316 delete_timer_group (); (* Delete the timer. *)
317 List.iter run_job jobs;
318 schedule_next_everyjob ()
320 Unixqueue.weak_once esys g t_diff run_jobs;
324 and new_timer_group () =
325 delete_timer_group ();
326 let g = Unixqueue.new_group esys in
327 timer_group := Some g;
330 and delete_timer_group () =
331 match !timer_group with
334 Unixqueue.clear esys g;
337 and string_of_time_t t =
339 sprintf "%04d-%02d-%02d %02d:%02d:%02d UTC"
340 (1900+tm.tm_year) (1+tm.tm_mon) tm.tm_mday
341 tm.tm_hour tm.tm_min tm.tm_sec
345 (* Increment JOBSERIAL. *)
347 match StringMap.find "JOBSERIAL" !variables with
349 let serial = succ_big_int serial in
350 variables := StringMap.add "JOBSERIAL" (T_int serial) !variables;
352 | _ -> assert false in
354 Syslog.notice "running %s (JOBSERIAL=%s)"
355 job.job_name (string_of_big_int serial) in
357 (* Create a temporary directory. The current directory of the job
358 * will be in this directory. The directory is removed when the
359 * child process exits.
361 let dir = tmpdir () in
364 if pid = 0 then ( (* child process running the job *)
367 (* Set environment variables corresponding to each variable. *)
369 (fun name value -> putenv name (string_of_variable value)) !variables;
371 (* Set the $JOBNAME environment variable. *)
372 putenv "JOBNAME" job.job_name;
374 (* Create a temporary file containing the shell script fragment. *)
375 let script = dir // "script" in
376 let chan = open_out script in
377 fprintf chan "set -e\n"; (* So that jobs exit on error. *)
378 output_string chan job.job_script.sh_script;
382 let shell = try getenv "SHELL" with Not_found -> "/bin/sh" in
384 (* Execute the shell script. *)
385 (try execvp shell [| shell; "-c"; script |];
386 with Unix_error (err, fn, _) ->
387 Syslog.error "%s failed: %s: %s" fn script (error_message err)
392 (* Remember this PID, the job and the temporary directory, so we
393 * can clean up when the child exits.
395 running := IntMap.add pid (job, dir) !running
398 let chan = open_in "/dev/urandom" in
399 let data = String.create 16 in
400 really_input chan data 0 (String.length data);
402 let data = Digest.to_hex (Digest.string data) in
403 let dir = Filename.temp_dir_name // sprintf "whenjobs%s" data in
407 (* This is called when a job (child process) exits. *)
408 and handle_sigchld _ =
410 let pid, status = waitpid [WNOHANG] 0 in
412 (* Look up the PID in the running jobs map. *)
413 let job, dir = IntMap.find pid !running in
414 running := IntMap.remove pid !running;
417 with Unix_error _ | Not_found -> ()
419 and cleanup_job job dir =
420 (* This should be safe because the path cannot contain shell metachars. *)
421 let cmd = sprintf "rm -rf '%s'" dir in
422 ignore (Sys.command cmd)
424 (* Intelligent comparison of job names. *)
425 and compare_jobnames name1 name2 =
427 let len1 = String.length name1
428 and len2 = String.length name2 in
429 if len1 > 4 && len2 > 4 &&
430 String.sub name1 0 4 = "job$" && String.sub name2 0 4 = "job$"
432 let i1 = int_of_string (String.sub name1 4 (len1-4)) in
433 let i2 = int_of_string (String.sub name2 4 (len2-4)) in