1 files changed, 52 insertions, 0 deletions
diff --git a/src/shared/signal.c b/src/shared/signal.c
new file mode 100644
index 0000000..a0697f8
--- /dev/null
+++ b/src/shared/signal.c
@@ -0,0 +1,52 @@
+#include "signal.h"
+#include <sys/eventfd.h>
+#include <poll.h>
+#include <inttypes.h>
+#include <errno.h>
+#include <unistd.h>
+
+int signal_new()
+{
+	return eventfd( 0, EFD_NONBLOCK );
+}
+
+int signal_newBlocking()
+{
+	return eventfd( 0, 0 );
+}
+
+int signal_call(int signalFd)
+{
+	if ( signalFd < 0 ) return 0;
+	static uint64_t one = 1;
+	return write( signalFd, &one, sizeof one ) == sizeof one;
+}
+
+int signal_wait(int signalFd, int timeoutMs)
+{
+	struct pollfd ps = {
+		.fd = signalFd,
+		.events = POLLIN
+	};
+	int ret = poll( &ps, 1, timeoutMs );
+	if ( ret == 0 ) return SIGNAL_TIMEOUT;
+	if ( ret == -1 ) return SIGNAL_ERROR;
+	if ( ps.revents & ( POLLERR | POLLNVAL ) ) return SIGNAL_ERROR;
+	return signal_clear( signalFd );
+}
+
+int signal_clear(int signalFd)
+{
+	uint64_t ret;
+	if ( read( signalFd, &ret, sizeof ret ) != sizeof ret ) {
+		if ( errno == EAGAIN ) return 0;
+		return SIGNAL_ERROR;
+	}
+	return (int)ret;
+}
+
+void signal_close(int signalFd)
+{
+	close( signalFd );
+}
+