device/usb/usb_device.h

   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 #ifndef DEVICE_USB_USB_DEVICE_H_
   6 #define DEVICE_USB_USB_DEVICE_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/callback.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/strings/string16.h"
  12
  13 namespace device {
  14
  15 class UsbDeviceHandle;
  16 struct UsbConfigDescriptor;
  17
  18 // A UsbDevice object represents a detected USB device, providing basic
  19 // information about it. Methods other than simple property accessors must be
  20 // called from the thread on which this object was created. For further
  21 // manipulation of the device, a UsbDeviceHandle must be created from Open()
  22 // method.
  23 class UsbDevice : public base::RefCountedThreadSafe<UsbDevice> {
  24  public:
  25   using OpenCallback = base::Callback<void(scoped_refptr<UsbDeviceHandle>)>;
  26   using ResultCallback = base::Callback<void(bool success)>;
  27
  28   // A unique identifier which remains stable for the lifetime of this device
  29   // object (i.e., until the device is unplugged or the USB service dies.)
  30   const std::string& guid() const { return guid_; }
  31
  32   // Accessors to basic information.
  33   uint16 vendor_id() const { return vendor_id_; }
  34   uint16 product_id() const { return product_id_; }
  35   const base::string16& manufacturer_string() const {
  36     return manufacturer_string_;
  37   }
  38   const base::string16& product_string() const { return product_string_; }
  39   const base::string16& serial_number() const { return serial_number_; }
  40
  41   // On ChromeOS the permission_broker service is used to change the ownership
  42   // of USB device nodes so that Chrome can open them. On other platforms these
  43   // functions are no-ops and always return true.
  44   virtual void CheckUsbAccess(const ResultCallback& callback);
  45
  46   // Creates a UsbDeviceHandle for further manipulation.
  47   virtual void Open(const OpenCallback& callback) = 0;
  48
  49   // Explicitly closes a device handle. This method will be automatically called
  50   // by the destructor of a UsbDeviceHandle as well.
  51   virtual bool Close(scoped_refptr<UsbDeviceHandle> handle) = 0;
  52
  53   // Gets the UsbConfigDescriptor for the active device configuration or nullptr
  54   // if the device is unconfigured.
  55   virtual const UsbConfigDescriptor* GetConfiguration() = 0;
  56
  57  protected:
  58   UsbDevice(uint16 vendor_id,
  59             uint16 product_id,
  60             const base::string16& manufacturer_string,
  61             const base::string16& product_string,
  62             const base::string16& serial_number);
  63   virtual ~UsbDevice();
  64
  65   // These members must be mutable by subclasses as necessary during device
  66   // enumeration. To preserve the thread safety of this object they must remain
  67   // constant afterwards.
  68   base::string16 manufacturer_string_;
  69   base::string16 product_string_;
  70   base::string16 serial_number_;
  71
  72  private:
  73   friend class base::RefCountedThreadSafe<UsbDevice>;
  74
  75   const std::string guid_;
  76   const uint16 vendor_id_;
  77   const uint16 product_id_;
  78
  79   DISALLOW_COPY_AND_ASSIGN(UsbDevice);
  80 };
  81
  82 }  // namespace device
  83
  84 #endif  // DEVICE_USB_USB_DEVICE_H_