merge revision(s) r47818,r47832: [Backport #9820]

	* signal.c (rb_f_kill): should not ignore signal unless the
	  default handler is registered.  [ruby-dev:48592] [Bug #9820]

	* signal.c (rb_f_kill): get rid of deadlock as unhandled and
	  discarded signals do not make interrupt_cond signaled.
	  based on the patch by Kazuki Tsujimoto at [ruby-dev:48606].
	  [Bug #9820]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@47956 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 13 insertions, 3 deletions

diff --git a/signal.c b/signal.c
index 82fad956df..3db044e517 100644
--- a/signal.c
+++ b/signal.c
@@ -343,6 +343,7 @@ ruby_default_signal(int sig)
     raise(sig);
 }
 
+static RETSIGTYPE sighandler(int sig);
 static int signal_ignored(int sig);
 static void signal_enque(int sig);
 
@@ -449,6 +450,7 @@ rb_f_kill(int argc, VALUE *argv)
 	    rb_pid_t pid = NUM2PIDT(argv[i]);
 
 	    if ((sig != 0) && (self != -1) && (pid == self)) {
+		int t;
 		/*
 		 * When target pid is self, many caller assume signal will be
 		 * delivered immediately and synchronously.
@@ -467,7 +469,12 @@ rb_f_kill(int argc, VALUE *argv)
 		    ruby_kill(pid, sig);
 		    break;
 		  default:
-		    if (signal_ignored(sig)) break;
+		    t = signal_ignored(sig);
+		    if (t) {
+			if (t < 0 && kill(pid, sig))
+			    rb_sys_fail(0);
+			break;
+		    }
 		    signal_enque(sig);
 		    wakeup = 1;
 		}
@@ -612,16 +619,19 @@ ruby_nativethread_signal(int signum, sighandler_t handler)
 static int
 signal_ignored(int sig)
 {
+    sighandler_t func;
 #ifdef POSIX_SIGNAL
     struct sigaction old;
     (void)VALGRIND_MAKE_MEM_DEFINED(&old, sizeof(old));
     if (sigaction(sig, NULL, &old) < 0) return FALSE;
-    return old.sa_handler == SIG_IGN;
+    func = old.sa_handler;
 #else
     sighandler_t old = signal(sig, SIG_DFL);
     signal(sig, old);
-    return old == SIG_IGN;
+    func = old;
 #endif
+    if (func == SIG_IGN) return 1;
+    return func == sighandler ? 0 : -1;
 }
 
 static void