device/serial/serial_io_handler.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "device/serial/serial_io_handler.h"
   6
   7 #include "base/bind.h"
   8 #include "base/files/file_path.h"
   9 #include "base/message_loop/message_loop.h"
  10 #include "base/strings/string_util.h"
  11
  12 namespace device {
  13
  14 SerialIoHandler::SerialIoHandler(
  15     scoped_refptr<base::SingleThreadTaskRunner> file_thread_task_runner,
  16     scoped_refptr<base::SingleThreadTaskRunner> ui_thread_task_runner)
  17     : file_thread_task_runner_(file_thread_task_runner),
  18       ui_thread_task_runner_(ui_thread_task_runner) {
  19   options_.bitrate = 9600;
  20   options_.data_bits = serial::DATA_BITS_EIGHT;
  21   options_.parity_bit = serial::PARITY_BIT_NO;
  22   options_.stop_bits = serial::STOP_BITS_ONE;
  23   options_.cts_flow_control = false;
  24   options_.has_cts_flow_control = true;
  25 }
  26
  27 SerialIoHandler::~SerialIoHandler() {
  28   DCHECK(CalledOnValidThread());
  29   Close();
  30 }
  31
  32 void SerialIoHandler::Open(const std::string& port,
  33                            const serial::ConnectionOptions& options,
  34                            const OpenCompleteCallback& callback) {
  35   DCHECK(CalledOnValidThread());
  36   DCHECK(open_complete_.is_null());
  37   open_complete_ = callback;
  38   DCHECK(file_thread_task_runner_.get());
  39   DCHECK(ui_thread_task_runner_.get());
  40   MergeConnectionOptions(options);
  41   RequestAccess(port, file_thread_task_runner_, ui_thread_task_runner_);
  42 }
  43
  44 void SerialIoHandler::RequestAccess(
  45     const std::string& port,
  46     scoped_refptr<base::SingleThreadTaskRunner> file_task_runner,
  47     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner) {
  48   OnRequestAccessComplete(port, true /* success */);
  49 }
  50
  51 void SerialIoHandler::OnRequestAccessComplete(const std::string& port,
  52                                               bool success) {
  53   DCHECK(CalledOnValidThread());
  54   if (success) {
  55     DCHECK(file_thread_task_runner_.get());
  56     file_thread_task_runner_->PostTask(
  57         FROM_HERE, base::Bind(&SerialIoHandler::StartOpen, this, port,
  58                               base::ThreadTaskRunnerHandle::Get()));
  59     return;
  60   } else {
  61     DCHECK(!open_complete_.is_null());
  62     OpenCompleteCallback callback = open_complete_;
  63     open_complete_.Reset();
  64     callback.Run(false);
  65     return;
  66   }
  67 }
  68
  69 void SerialIoHandler::MergeConnectionOptions(
  70     const serial::ConnectionOptions& options) {
  71   if (options.bitrate) {
  72     options_.bitrate = options.bitrate;
  73   }
  74   if (options.data_bits != serial::DATA_BITS_NONE) {
  75     options_.data_bits = options.data_bits;
  76   }
  77   if (options.parity_bit != serial::PARITY_BIT_NONE) {
  78     options_.parity_bit = options.parity_bit;
  79   }
  80   if (options.stop_bits != serial::STOP_BITS_NONE) {
  81     options_.stop_bits = options.stop_bits;
  82   }
  83   if (options.has_cts_flow_control) {
  84     DCHECK(options_.has_cts_flow_control);
  85     options_.cts_flow_control = options.cts_flow_control;
  86   }
  87 }
  88
  89 void SerialIoHandler::StartOpen(
  90     const std::string& port,
  91     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner) {
  92   DCHECK(!open_complete_.is_null());
  93   DCHECK(file_thread_task_runner_->RunsTasksOnCurrentThread());
  94   DCHECK(!file_.IsValid());
  95   // It's the responsibility of the API wrapper around SerialIoHandler to
  96   // validate the supplied path against the set of valid port names, and
  97   // it is a reasonable assumption that serial port names are ASCII.
  98   DCHECK(base::IsStringASCII(port));
  99   base::FilePath path(base::FilePath::FromUTF8Unsafe(MaybeFixUpPortName(port)));
 100   int flags = base::File::FLAG_OPEN | base::File::FLAG_READ |
 101               base::File::FLAG_EXCLUSIVE_READ | base::File::FLAG_WRITE |
 102               base::File::FLAG_EXCLUSIVE_WRITE | base::File::FLAG_ASYNC |
 103               base::File::FLAG_TERMINAL_DEVICE;
 104   base::File file(path, flags);
 105   io_task_runner->PostTask(FROM_HERE, base::Bind(&SerialIoHandler::FinishOpen,
 106                                                  this, Passed(file.Pass())));
 107 }
 108
 109 void SerialIoHandler::FinishOpen(base::File file) {
 110   DCHECK(CalledOnValidThread());
 111   DCHECK(!open_complete_.is_null());
 112   OpenCompleteCallback callback = open_complete_;
 113   open_complete_.Reset();
 114
 115   if (!file.IsValid()) {
 116     LOG(ERROR) << "Failed to open serial port: "
 117                << base::File::ErrorToString(file.error_details());
 118     callback.Run(false);
 119     return;
 120   }
 121
 122   file_ = file.Pass();
 123
 124   bool success = PostOpen() && ConfigurePortImpl();
 125   if (!success) {
 126     Close();
 127   }
 128
 129   callback.Run(success);
 130 }
 131
 132 bool SerialIoHandler::PostOpen() {
 133   return true;
 134 }
 135
 136 void SerialIoHandler::Close() {
 137   if (file_.IsValid()) {
 138     DCHECK(file_thread_task_runner_.get());
 139     file_thread_task_runner_->PostTask(
 140         FROM_HERE, base::Bind(&SerialIoHandler::DoClose, Passed(file_.Pass())));
 141   }
 142 }
 143
 144 // static
 145 void SerialIoHandler::DoClose(base::File port) {
 146   // port closed by destructor.
 147 }
 148
 149 void SerialIoHandler::Read(scoped_ptr<WritableBuffer> buffer) {
 150   DCHECK(CalledOnValidThread());
 151   DCHECK(!IsReadPending());
 152   pending_read_buffer_ = buffer.Pass();
 153   read_canceled_ = false;
 154   AddRef();
 155   ReadImpl();
 156 }
 157
 158 void SerialIoHandler::Write(scoped_ptr<ReadOnlyBuffer> buffer) {
 159   DCHECK(CalledOnValidThread());
 160   DCHECK(!IsWritePending());
 161   pending_write_buffer_ = buffer.Pass();
 162   write_canceled_ = false;
 163   AddRef();
 164   WriteImpl();
 165 }
 166
 167 void SerialIoHandler::ReadCompleted(int bytes_read,
 168                                     serial::ReceiveError error) {
 169   DCHECK(CalledOnValidThread());
 170   DCHECK(IsReadPending());
 171   scoped_ptr<WritableBuffer> pending_read_buffer = pending_read_buffer_.Pass();
 172   if (error == serial::RECEIVE_ERROR_NONE) {
 173     pending_read_buffer->Done(bytes_read);
 174   } else {
 175     pending_read_buffer->DoneWithError(bytes_read, error);
 176   }
 177   Release();
 178 }
 179
 180 void SerialIoHandler::WriteCompleted(int bytes_written,
 181                                      serial::SendError error) {
 182   DCHECK(CalledOnValidThread());
 183   DCHECK(IsWritePending());
 184   scoped_ptr<ReadOnlyBuffer> pending_write_buffer =
 185       pending_write_buffer_.Pass();
 186   if (error == serial::SEND_ERROR_NONE) {
 187     pending_write_buffer->Done(bytes_written);
 188   } else {
 189     pending_write_buffer->DoneWithError(bytes_written, error);
 190   }
 191   Release();
 192 }
 193
 194 bool SerialIoHandler::IsReadPending() const {
 195   DCHECK(CalledOnValidThread());
 196   return pending_read_buffer_ != NULL;
 197 }
 198
 199 bool SerialIoHandler::IsWritePending() const {
 200   DCHECK(CalledOnValidThread());
 201   return pending_write_buffer_ != NULL;
 202 }
 203
 204 void SerialIoHandler::CancelRead(serial::ReceiveError reason) {
 205   DCHECK(CalledOnValidThread());
 206   if (IsReadPending() && !read_canceled_) {
 207     read_canceled_ = true;
 208     read_cancel_reason_ = reason;
 209     CancelReadImpl();
 210   }
 211 }
 212
 213 void SerialIoHandler::CancelWrite(serial::SendError reason) {
 214   DCHECK(CalledOnValidThread());
 215   if (IsWritePending() && !write_canceled_) {
 216     write_canceled_ = true;
 217     write_cancel_reason_ = reason;
 218     CancelWriteImpl();
 219   }
 220 }
 221
 222 bool SerialIoHandler::ConfigurePort(const serial::ConnectionOptions& options) {
 223   MergeConnectionOptions(options);
 224   return ConfigurePortImpl();
 225 }
 226
 227 void SerialIoHandler::QueueReadCompleted(int bytes_read,
 228                                          serial::ReceiveError error) {
 229   base::MessageLoop::current()->PostTask(
 230       FROM_HERE,
 231       base::Bind(&SerialIoHandler::ReadCompleted, this, bytes_read, error));
 232 }
 233
 234 void SerialIoHandler::QueueWriteCompleted(int bytes_written,
 235                                           serial::SendError error) {
 236   base::MessageLoop::current()->PostTask(
 237       FROM_HERE,
 238       base::Bind(&SerialIoHandler::WriteCompleted, this, bytes_written, error));
 239 }
 240
 241 }  // namespace device