(use_sa_restart): New static variable.

(sig_on_signal): Add SA_RESTART if appropriate.
(oop_signal_new): Don't just blindly set FD_CLOEXEC and
	O_NONBLOCK.  Read the old settings first.
(oop_signal_use_sa_restart): New function.

Signed-off-by: Magnus Holmgren <magnus@kibibyte.se>

oop.h

@@ -120,4 +120,5 @@ oop_adapter_signal *oop_signal_new(oop_source *);
 void oop_signal_delete(oop_adapter_signal *);
 oop_source *oop_signal_source(oop_adapter_signal *);
 
+void oop_signal_use_sa_restart(void);
 #endif

signal.c

@@ -35,6 +35,7 @@ struct oop_adapter_signal {
 };
 
 static struct oop_adapter_signal *sig_owner[OOP_NUM_SIGNALS];
+static int use_sa_restart = 0;
 
 static oop_adapter_signal *verify_source(oop_source *source) {
 	oop_adapter_signal * const s = (oop_adapter_signal *) source;
@@ -137,6 +138,7 @@ static void sig_on_signal(oop_source *source,int sig,
 #ifdef SA_NODEFER
 		act.sa_flags &= ~SA_NODEFER;
 #endif
+		if (use_sa_restart) act.sa_flags |= SA_RESTART;
 		sigaction(sig,&act,NULL);
 	}
 }
@@ -220,3 +222,10 @@ void oop_signal_delete(oop_adapter_signal *s) {
 oop_source *oop_signal_source(oop_adapter_signal *s) {
 	return &s->oop;
 }
+
+void oop_signal_use_sa_restart(void) {
+	int i;
+	for (i = 0; i < OOP_NUM_SIGNALS; ++i)
+		assert(NULL == sig_owner[i] && "signal handler already registered");
+	use_sa_restart = 1;
+}