Adapt python scripts to use the new Forwarder2

tools/android/forwarder2/socket.cc

Index: tools/android/forwarder2/socket.cc
diff --git a/tools/android/forwarder2/socket.cc b/tools/android/forwarder2/socket.cc
index 898afc3d4b4dccfee8a75879a7d8bbac162668c1..5c26a440fbdbe0dcbd4d8ada310a6214ae33d7a4 100644
--- a/tools/android/forwarder2/socket.cc
+++ b/tools/android/forwarder2/socket.cc
@@ -36,6 +36,10 @@
 namespace {
 const int kNoTimeout = -1;
 const int kConnectTimeOut = 10;  // Seconds.
+
+bool FamilyIsTCP(int family) {
+  return family == AF_INET || family == AF_INET6;
+}
 }  // namespace
 
 namespace forwarder2 {
@@ -129,7 +133,6 @@ bool Socket::InitUnixSocket(const std::string& path, bool abstract) {
   abstract_ = abstract;
   family_ = PF_UNIX;
   addr_.addr_un.sun_family = family_;
-
   if (abstract) {
     // Copied from net/base/unix_domain_socket_posix.cc
     // Convert the path given into abstract socket name. It must start with
@@ -143,14 +146,12 @@ bool Socket::InitUnixSocket(const std::string& path, bool abstract) {
     memcpy(addr_.addr_un.sun_path, path.c_str(), path.size());
     addr_len_ = sizeof(sockaddr_un);
   }
-
   addr_ptr_ = reinterpret_cast<sockaddr*>(&addr_.addr_un);
   return InitSocketInternal();
 }
 
 bool Socket::InitTcpSocket(const std::string& host, int port) {
   port_ = port;
-
   if (host.empty()) {
     // Use localhost: INADDR_LOOPBACK
     family_ = AF_INET;
@@ -159,8 +160,7 @@ bool Socket::InitTcpSocket(const std::string& host, int port) {
   } else if (!Resolve(host)) {
     return false;
   }
-  CHECK(family_ == AF_INET || family_ == AF_INET6)
-      << "Invalid socket family.";
+  CHECK(FamilyIsTCP(family_)) << "Invalid socket family.";
   if (family_ == AF_INET) {
     addr_.addr4.sin_port = htons(port_);
     addr_ptr_ = reinterpret_cast<sockaddr*>(&addr_.addr4);
@@ -180,7 +180,7 @@ bool Socket::BindAndListen() {
     SetSocketError();
     return false;
   }
-  if (port_ == 0) {
+  if (port_ == 0 && FamilyIsTCP(family_)) {
     SockAddr addr;
     memset(&addr, 0, sizeof(addr));
     socklen_t addrlen = 0;
@@ -225,19 +225,25 @@ bool Socket::Accept(Socket* new_socket) {
 }
 
 bool Socket::Connect() {
-  // Set non-block because we use select.
-  fcntl(socket_, F_SETFL, fcntl(socket_, F_GETFL) | O_NONBLOCK);
+  // Set non-block because we use select for connect.
+  const int flags = fcntl(socket_, F_GETFL);
+  DCHECK(!(flags & O_NONBLOCK));
+  fcntl(socket_, F_SETFL, flags | O_NONBLOCK);
   errno = 0;
   if (HANDLE_EINTR(connect(socket_, addr_ptr_, addr_len_)) < 0 &&
       errno != EINPROGRESS) {
     SetSocketError();
+    PRESERVE_ERRNO_HANDLE_EINTR(fcntl(socket_, F_SETFL, flags));
     return false;
   }
   // Wait for connection to complete, or receive a notification.
   if (!WaitForEvent(WRITE, kConnectTimeOut)) {
     SetSocketError();
+    PRESERVE_ERRNO_HANDLE_EINTR(fcntl(socket_, F_SETFL, flags));
     return false;
   }
+  // Disable non-block since our code assumes blocking semantics.
+  fcntl(socket_, F_SETFL, flags);
   return true;
 }
 
@@ -271,7 +277,7 @@ bool Socket::Resolve(const std::string& host) {
 }
 
 int Socket::GetPort() {
-  if (family_ != AF_INET && family_ != AF_INET6) {
+  if (!FamilyIsTCP(family_)) {
     LOG(ERROR) << "Can't call GetPort() on an unix domain socket.";
     return 0;
   }