chrome/browser/usb/usb_service.h

   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 #ifndef CHROME_BROWSER_USB_USB_SERVICE_H_
   6 #define CHROME_BROWSER_USB_USB_SERVICE_H_
   7
   8 #include <map>
   9 #include <utility>
  10 #include <vector>
  11
  12 #include "base/basictypes.h"
  13 #include "base/callback.h"
  14 #include "base/memory/ref_counted.h"
  15
  16 namespace base {
  17
  18 template <class T> class DeleteHelper;
  19
  20 }  // namespace base
  21
  22 struct InitUsbContextTraits;
  23 template <typename T> struct DefaultSingletonTraits;
  24
  25 typedef struct libusb_device* PlatformUsbDevice;
  26 typedef struct libusb_context* PlatformUsbContext;
  27
  28 class UsbContext;
  29 class UsbDevice;
  30
  31 // The USB service handles creating and managing an event handler thread that is
  32 // used to manage and dispatch USB events. It is also responsible for device
  33 // discovery on the system, which allows it to re-use device handles to prevent
  34 // competition for the same USB device.
  35 class UsbService {
  36  public:
  37   typedef scoped_ptr<std::vector<scoped_refptr<UsbDevice> > >
  38       ScopedDeviceVector;
  39
  40   // Must be called on FILE thread.
  41   // Returns NULL when failed to initialized.
  42   static UsbService* GetInstance();
  43
  44   scoped_refptr<UsbDevice> GetDeviceById(uint32 unique_id);
  45
  46   // Get all of the devices attached to the system, inserting them into
  47   // |devices|. Clears |devices| before use. The result will be sorted by id
  48   // in increasing order. Must be called on FILE thread.
  49   void GetDevices(std::vector<scoped_refptr<UsbDevice> >* devices);
  50
  51  private:
  52   friend class base::DeleteHelper<UsbService>;
  53
  54   explicit UsbService(PlatformUsbContext context);
  55   virtual ~UsbService();
  56
  57   // Return true if |device|'s vendor and product identifiers match |vendor_id|
  58   // and |product_id|.
  59   static bool DeviceMatches(scoped_refptr<UsbDevice> device,
  60                             const uint16 vendor_id,
  61                             const uint16 product_id);
  62
  63   // Enumerate USB devices from OS and Update devices_ map.
  64   void RefreshDevices();
  65
  66   scoped_refptr<UsbContext> context_;
  67
  68   // TODO(ikarienator): Figure out a better solution.
  69   uint32 next_unique_id_;
  70
  71   // The map from PlatformUsbDevices to UsbDevices.
  72   typedef std::map<PlatformUsbDevice, scoped_refptr<UsbDevice> > DeviceMap;
  73   DeviceMap devices_;
  74
  75   DISALLOW_COPY_AND_ASSIGN(UsbService);
  76 };
  77
  78 #endif  // CHROME_BROWSER_USB_USB_SERVICE_H_