Adds a modified copy of talk/base to webrtc/base. It is the first step in migrating talk/base to webrtc/base.

BUG=N/A
R=andrew@webrtc.org, wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/12199004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6107 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/base/nethelpers.cc

@@ -0,0 +1,150 @@
+/*
+ *  Copyright 2008 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/base/nethelpers.h"
+
+#if defined(WEBRTC_WIN)
+#include <ws2spi.h>
+#include <ws2tcpip.h>
+#include "webrtc/base/win32.h"
+#endif
+
+#include "webrtc/base/byteorder.h"
+#include "webrtc/base/logging.h"
+#include "webrtc/base/signalthread.h"
+
+namespace rtc {
+
+int ResolveHostname(const std::string& hostname, int family,
+                    std::vector<IPAddress>* addresses) {
+#ifdef __native_client__
+  ASSERT(false);
+  LOG(LS_WARNING) << "ResolveHostname() is not implemented for NaCl";
+  return -1;
+#else  // __native_client__
+  if (!addresses) {
+    return -1;
+  }
+  addresses->clear();
+  struct addrinfo* result = NULL;
+  struct addrinfo hints = {0};
+  // TODO(djw): For now this is IPv4 only so existing users remain unaffected.
+  hints.ai_family = AF_INET;
+  hints.ai_flags = AI_ADDRCONFIG;
+  int ret = getaddrinfo(hostname.c_str(), NULL, &hints, &result);
+  if (ret != 0) {
+    return ret;
+  }
+  struct addrinfo* cursor = result;
+  for (; cursor; cursor = cursor->ai_next) {
+    if (family == AF_UNSPEC || cursor->ai_family == family) {
+      IPAddress ip;
+      if (IPFromAddrInfo(cursor, &ip)) {
+        addresses->push_back(ip);
+      }
+    }
+  }
+  freeaddrinfo(result);
+  return 0;
+#endif  // !__native_client__
+}
+
+// AsyncResolver
+AsyncResolver::AsyncResolver() : error_(-1) {
+}
+
+void AsyncResolver::Start(const SocketAddress& addr) {
+  addr_ = addr;
+  // SignalThred Start will kickoff the resolve process.
+  SignalThread::Start();
+}
+
+bool AsyncResolver::GetResolvedAddress(int family, SocketAddress* addr) const {
+  if (error_ != 0 || addresses_.empty())
+    return false;
+
+  *addr = addr_;
+  for (size_t i = 0; i < addresses_.size(); ++i) {
+    if (family == addresses_[i].family()) {
+      addr->SetResolvedIP(addresses_[i]);
+      return true;
+    }
+  }
+  return false;
+}
+
+void AsyncResolver::DoWork() {
+  error_ = ResolveHostname(addr_.hostname().c_str(), addr_.family(),
+                           &addresses_);
+}
+
+void AsyncResolver::OnWorkDone() {
+  SignalDone(this);
+}
+
+const char* inet_ntop(int af, const void *src, char* dst, socklen_t size) {
+#if defined(WEBRTC_WIN)
+  return win32_inet_ntop(af, src, dst, size);
+#else
+  return ::inet_ntop(af, src, dst, size);
+#endif
+}
+
+int inet_pton(int af, const char* src, void *dst) {
+#if defined(WEBRTC_WIN)
+  return win32_inet_pton(af, src, dst);
+#else
+  return ::inet_pton(af, src, dst);
+#endif
+}
+
+bool HasIPv6Enabled() {
+#if !defined(WEBRTC_WIN)
+  // We only need to check this for Windows XP (so far).
+  return true;
+#else
+  if (IsWindowsVistaOrLater()) {
+    return true;
+  }
+  if (!IsWindowsXpOrLater()) {
+    return false;
+  }
+  DWORD protbuff_size = 4096;
+  scoped_ptr<char[]> protocols;
+  LPWSAPROTOCOL_INFOW protocol_infos = NULL;
+  int requested_protocols[2] = {AF_INET6, 0};
+
+  int err = 0;
+  int ret = 0;
+  // Check for protocols in a do-while loop until we provide a buffer large
+  // enough. (WSCEnumProtocols sets protbuff_size to its desired value).
+  // It is extremely unlikely that this will loop more than once.
+  do {
+    protocols.reset(new char[protbuff_size]);
+    protocol_infos = reinterpret_cast<LPWSAPROTOCOL_INFOW>(protocols.get());
+    ret = WSCEnumProtocols(requested_protocols, protocol_infos,
+                           &protbuff_size, &err);
+  } while (ret == SOCKET_ERROR && err == WSAENOBUFS);
+
+  if (ret == SOCKET_ERROR) {
+    return false;
+  }
+
+  // Even if ret is positive, check specifically for IPv6.
+  // Non-IPv6 enabled WinXP will still return a RAW protocol.
+  for (int i = 0; i < ret; ++i) {
+    if (protocol_infos[i].iAddressFamily == AF_INET6) {
+      return true;
+    }
+  }
+  return false;
+#endif
+}
+}  // namespace rtc