* Kill a build if it has gone for more than a certain number of

  seconds without producing output on stdout or stderr (NIX-65).  This
  timeout can be specified using the `--max-silent-time' option or the
  `build-max-silent-time' configuration setting.  The default is
  infinity (0).

* Fix a tricky race condition: if we kill the build user before the
  child has done its setuid() to the build user uid, then it won't be
  killed, and we'll potentially lock up in pid.wait().  So also send a
  conventional kill to the child.

1 files changed, 18 insertions, 14 deletions

diff --git a/src/libmain/shared.cc b/src/libmain/shared.cc
index d7fb240192b6..f1a7db40dc91 100644
--- a/src/libmain/shared.cc
+++ b/src/libmain/shared.cc
@@ -57,6 +57,18 @@ static void setLogType(string lt)
 }
 
 
+static unsigned int getIntArg(const string & opt,
+    Strings::iterator & i, const Strings::iterator & end)
+{
+    ++i;
+    if (i == end) throw UsageError(format("`%1%' requires an argument") % opt);
+    int n;
+    if (!string2Int(*i, n) || n < 0)
+        throw UsageError(format("`%1%' requires a non-negative integer") % opt);
+    return n;
+}
+
+
 struct RemoveTempRoots 
 {
     ~RemoveTempRoots()
@@ -91,12 +103,8 @@ static void initAndRun(int argc, char * * argv)
 
     /* Get some settings from the configuration file. */
     thisSystem = querySetting("system", SYSTEM);
-    {
-        int n;
-        if (!string2Int(querySetting("build-max-jobs", "1"), n) || n < 0)
-            throw Error("invalid value for configuration setting `build-max-jobs'");
-        maxBuildJobs = n;
-    }
+    maxBuildJobs = queryIntSetting("build-max-jobs", 1);
+    maxSilentTime = queryIntSetting("build-max-silent-time", 0);
 
     /* Catch SIGINT. */
     struct sigaction act, oact;
@@ -180,16 +188,12 @@ static void initAndRun(int argc, char * * argv)
             keepGoing = true;
         else if (arg == "--fallback")
             tryFallback = true;
-        else if (arg == "--max-jobs" || arg == "-j") {
-            ++i;
-            if (i == args.end()) throw UsageError("`--max-jobs' requires an argument");
-            int n;
-            if (!string2Int(*i, n) || n < 0)
-                throw UsageError(format("`--max-jobs' requires a non-negative integer"));
-            maxBuildJobs = n;
-        }
+        else if (arg == "--max-jobs" || arg == "-j")
+            maxBuildJobs = getIntArg(arg, i, args.end());
         else if (arg == "--readonly-mode")
             readOnlyMode = true;
+        else if (arg == "--max-silent-time")
+            maxSilentTime = getIntArg(arg, i, args.end());
         else remaining.push_back(arg);
     }