components/usb_service/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 COMPONENTS_USB_SERVICE_USB_CONTEXT_H_
   6 #define COMPONENTS_USB_SERVICE_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 #include "components/usb_service/usb_service_export.h"
  13
  14 struct libusb_context;
  15
  16 namespace usb_service {
  17
  18 typedef libusb_context* PlatformUsbContext;
  19
  20 // Ref-counted wrapper for libusb_context*.
  21 // It also manages the life-cycle of UsbEventHandler.
  22 // It is a blocking operation to delete UsbContext.
  23 // Destructor must be called on FILE thread.
  24 class USB_SERVICE_EXPORT UsbContext
  25     : public base::RefCountedThreadSafe<UsbContext> {
  26  public:
  27   PlatformUsbContext context() const { return context_; }
  28
  29  protected:
  30   friend class UsbService;
  31   friend class base::RefCountedThreadSafe<UsbContext>;
  32
  33   explicit UsbContext(PlatformUsbContext context);
  34   virtual ~UsbContext();
  35
  36  private:
  37   class UsbEventHandler;
  38   PlatformUsbContext context_;
  39   UsbEventHandler* event_handler_;
  40   base::ThreadChecker thread_checker_;
  41
  42   DISALLOW_COPY_AND_ASSIGN(UsbContext);
  43 };
  44
  45 }  // namespace usb_service
  46
  47 #endif  // COMPONENTS_USB_SERVICE_USB_CONTEXT_H_