Ktest: Add SigInt handling

User can cancel tests and specify handler's behavior using option
'EMAIL_WHEN_CANCELED'.

Link: http://lkml.kernel.org/r/1522094884-22718-3-git-send-email-tianyang.chen@oracle.comSuggested-by: Dhaval Giani <dhaval.giani@oracle.com>
Signed-off-by: Tim Tianyang Chen <tianyang.chen@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

tools/testing/ktest/ktest.pl

@@ -4144,6 +4144,16 @@ sub send_email {
     }
 }
 
+sub cancel_test {
+    if ($email_when_canceled) {
+        send_email("KTEST: Your [$test_type] test was cancelled",
+                "Your test started at $script_start_time was cancelled: sig int");
+    }
+    die "\nCaught Sig Int, test interrupted: $!\n"
+}
+
+$SIG{INT} = qw(cancel_test);
+
 # First we need to do is the builds
 for (my $i = 1; $i <= $opt{"NUM_TESTS"}; $i++) {