Add forwarder2

tools/android/forwarder2/pipe_notifier.cc

Index: tools/android/forwarder2/pipe_notifier.cc
diff --git a/tools/android/forwarder2/pipe_notifier.cc b/tools/android/forwarder2/pipe_notifier.cc
new file mode 100644
index 0000000000000000000000000000000000000000..48e093596f121dad02635ecb74de8f6aefe51181
--- /dev/null
+++ b/tools/android/forwarder2/pipe_notifier.cc
@@ -0,0 +1,43 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "tools/android/forwarder2/pipe_notifier.h"
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include "base/eintr_wrapper.h"
+#include "base/logging.h"
+#include "base/safe_strerror_posix.h"
+
+namespace forwarder {
+
+PipeNotifier::PipeNotifier() {
+  int pipe_fd[2];
+  int ret = pipe(pipe_fd);
+  CHECK_EQ(0, ret);
+  receiver_fd_ = pipe_fd[0];
+  sender_fd_ = pipe_fd[1];
+  fcntl(sender_fd_, F_SETFL, O_NONBLOCK);
+}
+
+PipeNotifier::~PipeNotifier() {
+  (void) HANDLE_EINTR(close(receiver_fd_));
+  (void) HANDLE_EINTR(close(sender_fd_));
+}
+
+bool PipeNotifier::Notify() {
+  CHECK_NE(-1, sender_fd_);
+  errno = 0;
+  int ret = HANDLE_EINTR(write(sender_fd_, "1", 1));
+  if (ret < 0) {
+    LOG(WARNING) << "Error while notifying pipe. " << safe_strerror(errno);
+    return false;
+  }
+  return true;
+}
+
+}  // namespace forwarder