Update monet.

mojo/data_pipe_utils/data_pipe_drainer.cc

Index: mojo/data_pipe_utils/data_pipe_drainer.cc
diff --git a/mojo/data_pipe_utils/data_pipe_drainer.cc b/mojo/data_pipe_utils/data_pipe_drainer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8ed8b2d6cc4e0e9f9c3b1d1aa45ee0851f271e97
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+++ b/mojo/data_pipe_utils/data_pipe_drainer.cc
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+// Copyright 2014 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 "mojo/data_pipe_utils/data_pipe_drainer.h"
+
+#include "base/bind.h"
+
+namespace mojo {
+namespace common {
+
+DataPipeDrainer::DataPipeDrainer(Client* client,
+                                 mojo::ScopedDataPipeConsumerHandle source)
+    : client_(client), source_(source.Pass()), weak_factory_(this) {
+  DCHECK(client_);
+  ReadData();
+}
+
+DataPipeDrainer::~DataPipeDrainer() {}
+
+void DataPipeDrainer::ReadData() {
+  const void* buffer = nullptr;
+  uint32_t num_bytes = 0;
+  MojoResult rv = BeginReadDataRaw(source_.get(), &buffer, &num_bytes,
+                                   MOJO_READ_DATA_FLAG_NONE);
+  if (rv == MOJO_RESULT_OK) {
+    client_->OnDataAvailable(buffer, num_bytes);
+    EndReadDataRaw(source_.get(), num_bytes);
+    WaitForData();
+  } else if (rv == MOJO_RESULT_SHOULD_WAIT) {
+    WaitForData();
+  } else if (rv == MOJO_RESULT_FAILED_PRECONDITION) {
+    client_->OnDataComplete();
+  } else {
+    DCHECK(false) << "Unhandled MojoResult: " << rv;
+  }
+}
+
+void DataPipeDrainer::WaitForData() {
+  handle_watcher_.Start(
+      source_.get(), MOJO_HANDLE_SIGNAL_READABLE, MOJO_DEADLINE_INDEFINITE,
+      base::Bind(&DataPipeDrainer::WaitComplete, weak_factory_.GetWeakPtr()));
+}
+
+void DataPipeDrainer::WaitComplete(MojoResult result) {
+  ReadData();
+}
+
+}  // namespace common
+}  // namespace mojo