1 files changed, 124 insertions, 0 deletions

diff --git a/src/OSSupport/HostnameLookup.cpp b/src/OSSupport/HostnameLookup.cpp
new file mode 100644
index 000000000..3a2997ffd
--- /dev/null
+++ b/src/OSSupport/HostnameLookup.cpp
@@ -0,0 +1,124 @@
+
+// HostnameLookup.cpp
+
+// Implements the cHostnameLookup class representing an in-progress hostname-to-IP lookup
+
+#include "Globals.h"
+#include "HostnameLookup.h"
+#include <event2/dns.h>
+#include "NetworkSingleton.h"
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// cHostnameLookup:
+
+cHostnameLookup::cHostnameLookup(cNetwork::cResolveNameCallbacksPtr a_Callbacks):
+	m_Callbacks(a_Callbacks)
+{
+}
+
+
+
+
+
+void cHostnameLookup::Lookup(const AString & a_Hostname)
+{
+	// Store the hostname for the callback:
+	m_Hostname = a_Hostname;
+
+	// Start the lookup:
+	// Note that we don't have to store the LibEvent lookup handle, LibEvent will free it on its own.
+	evutil_addrinfo hints;
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_protocol = IPPROTO_TCP;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_flags = EVUTIL_AI_CANONNAME;
+	evdns_getaddrinfo(cNetworkSingleton::Get().GetDNSBase(), a_Hostname.c_str(), nullptr, &hints, Callback, this);
+}
+
+
+
+
+
+void cHostnameLookup::Callback(int a_ErrCode, evutil_addrinfo * a_Addr, void * a_Self)
+{
+	// Get the Self class:
+	cHostnameLookup * Self = reinterpret_cast<cHostnameLookup *>(a_Self);
+	ASSERT(Self != nullptr);
+
+	// If an error has occurred, notify the error callback:
+	if (a_ErrCode != 0)
+	{
+		Self->m_Callbacks->OnError(a_ErrCode, evutil_socket_error_to_string(a_ErrCode));
+		cNetworkSingleton::Get().RemoveHostnameLookup(Self);
+		return;
+	}
+
+	// Call the success handler for each entry received:
+	bool HasResolved = false;
+	evutil_addrinfo * OrigAddr = a_Addr;
+	for (;a_Addr != nullptr; a_Addr = a_Addr->ai_next)
+	{
+		char IP[128];
+		switch (a_Addr->ai_family)
+		{
+			case AF_INET:  // IPv4
+			{
+				sockaddr_in * sin = reinterpret_cast<sockaddr_in *>(a_Addr->ai_addr);
+				evutil_inet_ntop(AF_INET, &(sin->sin_addr), IP, sizeof(IP));
+				break;
+			}
+			case AF_INET6:  // IPv6
+			{
+				sockaddr_in6 * sin = reinterpret_cast<sockaddr_in6 *>(a_Addr->ai_addr);
+				evutil_inet_ntop(AF_INET6, &(sin->sin6_addr), IP, sizeof(IP));
+				break;
+			}
+			default:
+			{
+				// Unknown address family, handle as if this entry wasn't received
+				continue;  // for (a_Addr)
+			}
+		}
+		Self->m_Callbacks->OnNameResolved(Self->m_Hostname, IP);
+		HasResolved = true;
+	}  // for (a_Addr)
+
+	// If only unsupported families were reported, call the Error handler:
+	if (!HasResolved)
+	{
+		Self->m_Callbacks->OnError(DNS_ERR_NODATA, "The name does not resolve to any known address.");
+	}
+	else
+	{
+		Self->m_Callbacks->OnFinished();
+	}
+	evutil_freeaddrinfo(OrigAddr);
+	cNetworkSingleton::Get().RemoveHostnameLookup(Self);
+}
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// cNetwork API:
+
+bool cNetwork::HostnameToIP(
+	const AString & a_Hostname,
+	cNetwork::cResolveNameCallbacksPtr a_Callbacks
+)
+{
+	auto Lookup = std::make_shared<cHostnameLookup>(a_Callbacks);
+	cNetworkSingleton::Get().AddHostnameLookup(Lookup);
+	Lookup->Lookup(a_Hostname);
+	return true;
+}
+
+
+
+