add DNS plugin

plugins/dns/thread.c

@@ -0,0 +1,33 @@
+#include <fcntl.h>
+#include "thread.h"
+
+thread *
+thread_new (void)
+{
+	thread *th;
+
+	th = calloc (1, sizeof (*th));
+	if (!th)
+	{
+		return NULL;
+	}
+
+	if (_pipe (th->pipe_fd, 4096, _O_BINARY) == -1)
+	{
+		free (th);
+		return NULL;
+	}
+
+	return th;
+}
+
+int
+thread_start (thread *th, void *(*start_routine)(void *), void *arg)
+{
+	DWORD id;
+
+	CloseHandle (CreateThread (NULL, 0, (LPTHREAD_START_ROUTINE)start_routine, arg, 0, (DWORD *)&id));
+	th->threadid = id;
+
+	return 1;
+}