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.
27 external _exit : int -> 'a = "whenjobs__exit"
29 (* All jobs that are loaded. Maps name -> [job] structure. *)
30 let jobs = ref StringMap.empty
32 (* Map variable names to jobs which depend on that variable. This
33 * gives us a quick way to tell which jobs might need to be reevaluated
34 * when a variable is set.
36 let dependencies = ref StringMap.empty
38 (* Current values of variables. Using the referentially transparent
39 * type Map is very useful here because it lets us cheaply keep
40 * previous values of variables.
42 let variables : variables ref = ref StringMap.empty
47 (* Jobs that are running; map of PID -> (job, other data). Note that
48 * the job may no longer exist *OR* it may have been renamed,
49 * eg. if the jobs file was reloaded.
51 let running = ref IntMap.empty
53 (* Was debugging requested on the command line? *)
59 let esys = Unixqueue.standard_event_system ()
61 (* The timer. It's convenient to have this as a global variable
62 * because (a) there should only be one timer (which fires when the
63 * soonest every-job becomes ready), and (b) it's complicated to track
64 * that timer and avoid it getting double-scheduled (eg. when we
65 * reload the jobs file) without having a global variable.
67 let timer_group = ref None
73 Whenlock.create_lock !jobsdir;
75 (* Remove old socket if it exists. *)
76 let addr = sprintf "%s/socket" !jobsdir in
77 (try unlink addr with Unix_error _ -> ());
80 Whenproto_srv.When.V1.create_server
84 ~proc_get_variable_names
86 (Rpc_server.Unix addr)
87 Rpc.Tcp (* not TCP, this is the same as SOCK_STREAM *)
92 (* Handle SIGCHLD to clean up jobs. *)
93 Sys.set_signal Sys.sigchld (Sys.Signal_handle handle_sigchld);
95 (* Initialize the variables. XXX Eventually this will be saved
96 * and loaded from a persistent store.
98 variables := StringMap.add "JOBSERIAL" (T_int zero_big_int) !variables
100 and proc_reload_file () =
101 if !debug then Syslog.notice "remote call: reload_file";
103 try reload_file (); `ok
104 with Failure err -> `error err
106 and proc_set_variable (name, value) =
107 if !debug then Syslog.notice "remote call: set_variable %s" name;
110 (* Don't permit certain names. *)
111 if name = "JOBSERIAL" then
112 failwith "JOBSERIAL variable cannot be set";
114 let len = String.length name in
116 failwith "variable name is an empty string";
117 if name.[0] <> '_' && not (isalpha name.[0]) then
118 failwith "variable name must start with alphabetic character or underscore";
122 else if name.[i] <> '_' && not (isalnum name.[i]) then
123 failwith "variable name contains non-alphanumeric non-underscore character"
128 let value = variable_of_rpc value in
129 variables := StringMap.add name value !variables;
131 (* Which jobs need to be re-evaluated? *)
132 let jobnames = try StringMap.find name !dependencies with Not_found -> [] in
133 reevaluate_whenjobs jobnames;
137 Failure msg -> `error msg
139 and proc_get_variable name =
140 if !debug then Syslog.notice "remote call: get_variable %s" name;
142 try rpc_of_variable (StringMap.find name !variables)
143 with (* all non-existent variables are empty strings *)
144 Not_found -> `string_t ""
146 and proc_get_variable_names () =
147 if !debug then Syslog.notice "remote call: get_variable_names";
149 (* Only return variables that are non-empty. *)
150 let vars = StringMap.fold (
151 fun name value xs -> if value <> T_string "" then name :: xs else xs
153 let vars = Array.of_list vars in
154 Array.sort compare vars;
157 and proc_exit_daemon () =
158 if !debug then Syslog.notice "remote call: exit_daemon";
162 `error "exit_daemon: no server handle"
164 Rpc_server.stop_server ~graceful:true s;
168 (* Reload the jobs file. *)
170 let file = sprintf "%s/jobs.cmo" !jobsdir in
175 Dynlink.loadfile file;
176 let jobs = Whenfile.get_jobs () in
177 Syslog.notice "loaded %d job(s) from %s" (List.length jobs) file;
180 | Dynlink.Error err ->
181 let err = Dynlink.error_message err in
182 Syslog.error "error loading jobs: %s" err;
185 failwith (Printexc.to_string exn) in
187 (* Set 'jobs' and related global variables. *)
189 let map = List.fold_left (
191 let name = j.job_name in
192 StringMap.add name j map
193 ) StringMap.empty js in
197 let map = List.fold_left (
199 let deps = dependencies_of_job j in
200 let name = j.job_name in
203 let names = try StringMap.find d map with Not_found -> [] in
204 StringMap.add d (name :: names) map
206 ) StringMap.empty js in
207 dependencies := map in
209 (* Re-evaluate all when jobs. *)
210 reevaluate_whenjobs ~onload:true (StringMap.keys !jobs);
212 (* Schedule the next every job to run. *)
213 schedule_next_everyjob ()
215 (* Re-evaluate each named when-statement job, in a loop until we reach
216 * a fixpoint. Run those that need to be run. every-statement jobs
219 and reevaluate_whenjobs ?(onload=false) jobnames =
220 let rec loop set jobnames =
225 try StringMap.find jobname !jobs
226 with Not_found -> assert false in
227 assert (jobname = job.job_name);
230 try job_evaluate job !variables onload
231 with Invalid_argument err | Failure err ->
232 Syslog.error "error evaluating job %s (at %s): %s"
233 jobname (Camlp4.PreCast.Ast.Loc.to_string job.job_loc) err;
236 jobs := StringMap.add jobname job' !jobs;
239 Syslog.notice "evaluate %s -> %b\n" jobname r;
241 if r then StringSet.add jobname set else set
243 if StringSet.compare set set' <> 0 then
248 let set = loop StringSet.empty jobnames in
249 let jobnames = StringSet.elements set in
250 (* Ensure the jobs always run in predictable (name) order. *)
251 let jobnames = List.sort compare_jobnames jobnames in
253 (List.map (fun jobname -> StringMap.find jobname !jobs) jobnames)
255 (* Schedule the next every-statement job to run, if there is one. We
256 * look at the every jobs, work out the time that each must run at,
257 * pick the job(s) which must run soonest, and schedule a timer to run
258 * them. When the timer fires, it runs those jobs, then calls this
261 and schedule_next_everyjob () =
264 (* Get only everyjobs. *)
265 let jobs = StringMap.values !jobs in
266 let jobs = filter_map (
268 | { job_cond = Every_job period } as job -> Some (job, period)
269 | { job_cond = When_job _ } -> None
272 (* Map everyjob to next time it must run. *)
273 let jobs = List.map (
275 let t' = next_periodexpr t period in
276 assert (t' > t); (* serious bug in next_periodexpr if false *)
280 (* Sort, soonest first. *)
281 let jobs = List.sort (fun (_,a) (_,b) -> compare a b) jobs in
286 Syslog.notice "%s: next scheduled run at %s"
287 job.job_name (string_of_time_t t)
291 (* Pick the job(s) which run soonest. *)
292 let rec pick = function
295 | (j1, t) :: (j2, t') :: _ when t < t' -> t, [j1]
296 | (j1, t) :: (((j2, t') :: _) as rest) -> t, (j1 :: snd (pick rest))
298 let t, jobs = pick jobs in
302 (* Ensure the jobs always run in predictable (name) order. *)
304 List.sort (fun {job_name = a} {job_name = b} -> compare_jobnames a b)
308 Syslog.notice "scheduling job(s) %s to run at %s"
309 (String.concat ", " (List.map (fun { job_name = name } -> name) jobs))
310 (string_of_time_t t);
312 (* Schedule them to run at time t. *)
313 let g = new_timer_group () in
314 let t_diff = t -. Unix.time () in
315 let t_diff = if t_diff < 0. then 0. else t_diff in
317 delete_timer_group (); (* Delete the timer. *)
318 List.iter run_job jobs;
319 schedule_next_everyjob ()
321 Unixqueue.weak_once esys g t_diff run_jobs;
325 and new_timer_group () =
326 delete_timer_group ();
327 let g = Unixqueue.new_group esys in
328 timer_group := Some g;
331 and delete_timer_group () =
332 match !timer_group with
335 Unixqueue.clear esys g;
338 and string_of_time_t t =
340 sprintf "%04d-%02d-%02d %02d:%02d:%02d UTC"
341 (1900+tm.tm_year) (1+tm.tm_mon) tm.tm_mday
342 tm.tm_hour tm.tm_min tm.tm_sec
346 (* Increment JOBSERIAL. *)
348 match StringMap.find "JOBSERIAL" !variables with
350 let serial = succ_big_int serial in
351 variables := StringMap.add "JOBSERIAL" (T_int serial) !variables;
353 | _ -> assert false in
355 Syslog.notice "running %s (JOBSERIAL=%s)"
356 job.job_name (string_of_big_int serial) in
358 (* Create a temporary directory. The current directory of the job
359 * will be in this directory. The directory is removed when the
360 * child process exits.
362 let dir = tmpdir () in
365 if pid = 0 then ( (* child process running the job *)
368 (* Set environment variables corresponding to each variable. *)
370 (fun name value -> putenv name (string_of_variable value)) !variables;
372 (* Set the $JOBNAME environment variable. *)
373 putenv "JOBNAME" job.job_name;
375 (* Create a temporary file containing the shell script fragment. *)
376 let script = dir // "script" in
377 let chan = open_out script in
378 fprintf chan "set -e\n"; (* So that jobs exit on error. *)
379 output_string chan job.job_script.sh_script;
383 let shell = try getenv "SHELL" with Not_found -> "/bin/sh" in
385 (* Execute the shell script. *)
386 (try execvp shell [| shell; "-c"; script |];
387 with Unix_error (err, fn, _) ->
388 Syslog.error "%s failed: %s: %s" fn script (error_message err)
393 (* Remember this PID, the job and the temporary directory, so we
394 * can clean up when the child exits.
396 running := IntMap.add pid (job, dir) !running
399 let chan = open_in "/dev/urandom" in
400 let data = String.create 16 in
401 really_input chan data 0 (String.length data);
403 let data = Digest.to_hex (Digest.string data) in
404 let dir = Filename.temp_dir_name // sprintf "whenjobs%s" data in
408 (* This is called when a job (child process) exits. *)
409 and handle_sigchld _ =
411 let pid, status = waitpid [WNOHANG] 0 in
413 (* Look up the PID in the running jobs map. *)
414 let job, dir = IntMap.find pid !running in
415 running := IntMap.remove pid !running;
418 with Unix_error _ | Not_found -> ()
420 and cleanup_job job dir =
421 (* This should be safe because the path cannot contain shell metachars. *)
422 let cmd = sprintf "rm -rf '%s'" dir in
423 ignore (Sys.command cmd)
425 (* Intelligent comparison of job names. *)
426 and compare_jobnames name1 name2 =
428 let len1 = String.length name1
429 and len2 = String.length name2 in
430 if len1 > 4 && len2 > 4 &&
431 String.sub name1 0 4 = "job$" && String.sub name2 0 4 = "job$"
433 let i1 = int_of_string (String.sub name1 4 (len1-4)) in
434 let i2 = int_of_string (String.sub name2 4 (len2-4)) in