src/chrome/browser/extensions/api/serial/serial_connection.cc

   1 // Copyright (c) 2012 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 "chrome/browser/extensions/api/serial/serial_connection.h"
   6
   7 #include <string>
   8
   9 #include "base/files/file_path.h"
  10 #include "base/lazy_instance.h"
  11 #include "base/strings/string_util.h"
  12 #include "chrome/browser/extensions/api/api_resource_manager.h"
  13 #include "chrome/common/extensions/api/serial.h"
  14
  15 namespace serial = extensions::api::serial;
  16
  17 namespace extensions {
  18
  19 const char kSerialConnectionNotFoundError[] = "Serial connection not found";
  20
  21 static base::LazyInstance<ProfileKeyedAPIFactory<
  22     ApiResourceManager<SerialConnection> > >
  23         g_factory = LAZY_INSTANCE_INITIALIZER;
  24
  25 // static
  26 template <>
  27 ProfileKeyedAPIFactory<ApiResourceManager<SerialConnection> >*
  28 ApiResourceManager<SerialConnection>::GetFactoryInstance() {
  29   return &g_factory.Get();
  30 }
  31
  32 SerialConnection::SerialConnection(const std::string& port, int bitrate,
  33                                    serial::DataBit databit,
  34                                    serial::ParityBit parity,
  35                                    serial::StopBit stopbit,
  36                                    const std::string& owner_extension_id)
  37     : ApiResource(owner_extension_id), port_(port), bitrate_(bitrate),
  38       databit_(databit), parity_(parity), stopbit_(stopbit),
  39       file_(base::kInvalidPlatformFileValue) {
  40   CHECK_GE(bitrate, 0);
  41 }
  42
  43 SerialConnection::~SerialConnection() {
  44   Close();
  45 }
  46
  47 bool SerialConnection::Open() {
  48   bool created = false;
  49
  50   // It's the responsibility of the API wrapper around SerialConnection to
  51   // validate the supplied path against the set of valid port names, and
  52   // it is a reasonable assumption that serial port names are ASCII.
  53   CHECK(IsStringASCII(port_));
  54   base::FilePath file_path(
  55       base::FilePath::FromUTF8Unsafe(MaybeFixUpPortName(port_)));
  56
  57   file_ = base::CreatePlatformFile(file_path,
  58     base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ |
  59     base::PLATFORM_FILE_WRITE | base::PLATFORM_FILE_EXCLUSIVE_READ |
  60     base::PLATFORM_FILE_EXCLUSIVE_WRITE |
  61     base::PLATFORM_FILE_TERMINAL_DEVICE, &created, NULL);
  62   if (file_ == base::kInvalidPlatformFileValue) {
  63     return false;
  64   }
  65   return PostOpen();
  66 }
  67
  68 void SerialConnection::Close() {
  69   if (file_ != base::kInvalidPlatformFileValue) {
  70     base::ClosePlatformFile(file_);
  71     file_ = base::kInvalidPlatformFileValue;
  72   }
  73 }
  74
  75 int SerialConnection::Read(scoped_refptr<net::IOBufferWithSize> io_buffer) {
  76   DCHECK(io_buffer->data());
  77   return base::ReadPlatformFileAtCurrentPos(file_, io_buffer->data(),
  78                                             io_buffer->size());
  79 }
  80
  81 int SerialConnection::Write(scoped_refptr<net::IOBuffer> io_buffer,
  82                             int byte_count) {
  83   DCHECK(io_buffer->data());
  84   DCHECK_GE(byte_count, 0);
  85   return base::WritePlatformFileAtCurrentPos(file_, io_buffer->data(),
  86                                              byte_count);
  87 }
  88
  89 void SerialConnection::Flush() {
  90   base::FlushPlatformFile(file_);
  91 }
  92
  93 }  // namespace extensions