[FIX JENKINS-41864] Add warning for rare dates

Previously, impossible dates caused 100% CPU while Jenkins was trying to find the previous/next occurrence of the date.
jenkinsci · Feb 20, 2017 · 6e5225c · 6e5225c
1 parent 0e67ad4
commit 6e5225c
Show file tree

Hide file tree

Showing 4 changed files with 58 additions and 7 deletions.
diff --git a/core/src/main/java/hudson/scheduler/CronTab.java b/core/src/main/java/hudson/scheduler/CronTab.java
@@ -328,8 +328,14 @@ public Calendar ceil(long t) {
      * This method modifies the given calendar and returns the same object.
      */
     public Calendar ceil(Calendar cal) {
+        Calendar twoYearsFuture = (Calendar) cal.clone();
+        twoYearsFuture.add(Calendar.YEAR, 2);
         OUTER:
         while (true) {
+            if (cal.compareTo(twoYearsFuture) > 0) {
+                // we went at least two years into the future
+                throw new RareOrImpossibleDateException();
+            }
             for (CalendarField f : CalendarField.ADJUST_ORDER) {
                 int cur = f.valueOf(cal);
                 int next = f.ceil(this,cur);
@@ -380,8 +386,15 @@ public Calendar floor(long t) {
      * This method modifies the given calendar and returns the same object.
      */
     public Calendar floor(Calendar cal) {
+        Calendar twoYearsAgo = (Calendar) cal.clone();
+        twoYearsAgo.add(Calendar.YEAR, -2);
+
         OUTER:
         while (true) {
+            if (cal.compareTo(twoYearsAgo) < 0) {
+                // we went at least two years into the past
+                throw new RareOrImpossibleDateException();
+            }
             for (CalendarField f : CalendarField.ADJUST_ORDER) {
                 int cur = f.valueOf(cal);
                 int next = f.floor(this,cur);

diff --git a/core/src/main/java/hudson/scheduler/RareOrImpossibleDateException.java b/core/src/main/java/hudson/scheduler/RareOrImpossibleDateException.java
@@ -0,0 +1,31 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2017 CloudBees, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package hudson.scheduler;
+
+import org.kohsuke.accmod.Restricted;
+import org.kohsuke.accmod.restrictions.NoExternalUse;
+
+@Restricted(NoExternalUse.class)
+public class RareOrImpossibleDateException extends RuntimeException {
+}
diff --git a/core/src/main/java/hudson/triggers/TimerTrigger.java b/core/src/main/java/hudson/triggers/TimerTrigger.java
@@ -32,6 +32,7 @@
 import hudson.model.Item;
 import hudson.scheduler.CronTabList;
 import hudson.scheduler.Hash;
+import hudson.scheduler.RareOrImpossibleDateException;
 import hudson.util.FormValidation;
 import java.text.DateFormat;
 import java.util.ArrayList;
@@ -104,13 +105,17 @@ private void updateValidationsForSanity(Collection<FormValidation> validations,
         }
 
         private void updateValidationsForNextRun(Collection<FormValidation> validations, CronTabList ctl) {
-            Calendar prev = ctl.previous();
-            Calendar next = ctl.next();
-            if (prev != null && next != null) {
-                DateFormat fmt = DateFormat.getDateTimeInstance(DateFormat.FULL, DateFormat.FULL);
-                validations.add(FormValidation.ok(Messages.TimerTrigger_would_last_have_run_at_would_next_run_at(fmt.format(prev.getTime()), fmt.format(next.getTime()))));
-            } else {
-                validations.add(FormValidation.warning(Messages.TimerTrigger_no_schedules_so_will_never_run()));
+            try {
+                Calendar prev = ctl.previous();
+                Calendar next = ctl.next();
+                if (prev != null && next != null) {
+                    DateFormat fmt = DateFormat.getDateTimeInstance(DateFormat.FULL, DateFormat.FULL);
+                    validations.add(FormValidation.ok(Messages.TimerTrigger_would_last_have_run_at_would_next_run_at(fmt.format(prev.getTime()), fmt.format(next.getTime()))));
+                } else {
+                    validations.add(FormValidation.warning(Messages.TimerTrigger_no_schedules_so_will_never_run()));
+                }
+            } catch (RareOrImpossibleDateException ex) {
+                validations.add(FormValidation.warning(Messages.TimerTrigger_the_specified_cron_tab_is_rare_or_impossible()));
             }
         }
     }

diff --git a/core/src/main/resources/hudson/triggers/Messages.properties b/core/src/main/resources/hudson/triggers/Messages.properties
@@ -29,5 +29,7 @@ TimerTrigger.MissingWhitespace=You appear to be missing whitespace between * and
 TimerTrigger.no_schedules_so_will_never_run=No schedules so will never run
 TimerTrigger.TimerTriggerCause.ShortDescription=Started by timer
 TimerTrigger.would_last_have_run_at_would_next_run_at=Would last have run at {0}; would next run at {1}.
+TimerTrigger.the_specified_cron_tab_is_rare_or_impossible=This cron tab will match dates only rarely (e.g. February 29) or \
+  never (e.g. June 31), so this job may be triggered very rarely, if at all.
 Trigger.init=Initializing timer for triggers
 SCMTrigger.AdministrativeMonitorImpl.DisplayName=Too Many SCM Polling Threads