device/usb/usb_context.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_CONTEXT_H_
   6 #define DEVICE_USB_USB_CONTEXT_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/threading/thread_checker.h"
  12
  13 struct libusb_context;
  14
  15 namespace device {
  16
  17 typedef libusb_context* PlatformUsbContext;
  18
  19 // Ref-counted wrapper for libusb_context*.
  20 // It also manages the life-cycle of UsbEventHandler.
  21 // It is a blocking operation to delete UsbContext.
  22 // Destructor must be called on FILE thread.
  23 class UsbContext : public base::RefCountedThreadSafe<UsbContext> {
  24  public:
  25   PlatformUsbContext context() const { return context_; }
  26
  27  protected:
  28   friend class UsbServiceImpl;
  29   friend class base::RefCountedThreadSafe<UsbContext>;
  30
  31   explicit UsbContext(PlatformUsbContext context);
  32   virtual ~UsbContext();
  33
  34  private:
  35   class UsbEventHandler;
  36   PlatformUsbContext context_;
  37   UsbEventHandler* event_handler_;
  38   base::ThreadChecker thread_checker_;
  39
  40   DISALLOW_COPY_AND_ASSIGN(UsbContext);
  41 };
  42
  43 }  // namespace device
  44
  45 #endif  // DEVICE_USB_USB_CONTEXT_H_