Implement the host side of serial connection I/O on data pipe.

device/serial/test_serial_io_handler.h

 // 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.
 
 #ifndef DEVICE_SERIAL_TEST_SERIAL_IO_HANDLER_H_
 #define DEVICE_SERIAL_TEST_SERIAL_IO_HANDLER_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 22 matching lines @@
   virtual bool SetControlSignals(
       const serial::HostControlSignals& signals) OVERRIDE;
 
   serial::ConnectionInfo* connection_info() { return &info_; }
   serial::DeviceControlSignals* device_control_signals() {
     return &device_control_signals_;
   }
   bool dtr() { return dtr_; }
   bool rts() { return rts_; }
   int flushes() { return flushes_; }
+  // This callback will be called when this IoHandler processes its next write,
+  // instead of the normal behavior of echoing the data to reads.
+  void set_send_callback(const base::Closure& callback) {
+    send_callback_ = callback;
+  }
 
  protected:
   virtual ~TestSerialIoHandler();
 
  private:
   bool opened_;
   serial::ConnectionInfo info_;
   serial::DeviceControlSignals device_control_signals_;
   bool dtr_;
   bool rts_;
   mutable int flushes_;
+  std::string buffer_;
+  base::Closure send_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(TestSerialIoHandler);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_SERIAL_TEST_SERIAL_IO_HANDLER_H_