1 files changed, 69 insertions, 0 deletions
diff --git a/src/shrpx_dual_dns_resolver.h b/src/shrpx_dual_dns_resolver.h
new file mode 100644
index 0000000..98065da
--- /dev/null
+++ b/src/shrpx_dual_dns_resolver.h
@@ -0,0 +1,69 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2016 Tatsuhiro Tsujikawa
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef SHRPX_DUAL_DNS_RESOLVER_H
+#define SHRPX_DUAL_DNS_RESOLVER_H
+
+#include "shrpx.h"
+
+#include <ev.h>
+
+#include "shrpx_dns_resolver.h"
+
+using namespace nghttp2;
+
+namespace shrpx {
+
+// DualDNSResolver performs name resolution for both A and AAAA
+// records at the same time.  The first successful return (or if we
+// have both successful results, prefer to AAAA) is chosen.  This is
+// wrapper around 2 DNSResolver inside.  resolve(), get_status(), and
+// how CompleteCb is called have the same semantics with DNSResolver.
+class DualDNSResolver {
+public:
+  // |family| controls IP version preference.  If |family| ==
+  // AF_UNSPEC, bot A and AAAA lookups are performed.  If |family| ==
+  // AF_INET, only A lookup is performed.  If |family| == AF_INET6,
+  // only AAAA lookup is performed.
+  DualDNSResolver(struct ev_loop *loop, int family);
+
+  // Resolves |host|.  |host| must be NULL-terminated string.
+  int resolve(const StringRef &host);
+  CompleteCb get_complete_cb() const;
+  void set_complete_cb(CompleteCb cb);
+  DNSResolverStatus get_status(Address *result) const;
+
+private:
+  // IP version preference.
+  int family_;
+  // For A record
+  DNSResolver resolv4_;
+  // For AAAA record
+  DNSResolver resolv6_;
+  CompleteCb complete_cb_;
+};
+
+} // namespace shrpx
+
+#endif // SHRPX_DUAL_DNS_RESOLVER_H