LibUsbThread.h

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Library General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * LibUsbThread.h
 * The thread for asynchronous libusb communication.
 * Copyright (C) 2014 Simon Newton
 */

#ifndef PLUGINS_USBDMX_LIBUSBTHREAD_H_
#define PLUGINS_USBDMX_LIBUSBTHREAD_H_

#include <libusb.h>

#include "ola/base/Macro.h"
#include "ola/thread/Thread.h"

namespace ola {
namespace plugin {
namespace usbdmx {

class LibUsbThread : private ola::thread::Thread {
 public:
 explicit LibUsbThread(libusb_context *context)
 : m_context(context),
 m_term(false) {
 }

 virtual ~LibUsbThread() {}

 virtual bool Init() {
 return true;
 }

 virtual void Shutdown() {}

 void *Run();

 virtual void OpenHandle() = 0;

 virtual void CloseHandle(libusb_device_handle *handle) = 0;

 protected:
 void SetTerminate() {
 ola::thread::MutexLocker locker(&m_term_mutex);
 m_term = true;
 }

 void LaunchThread();

 void JoinThread();

 libusb_context* Context() const { return m_context; }

 private:
 libusb_context *m_context;
 bool m_term; // GUARDED_BY(m_term_mutex)
 ola::thread::Mutex m_term_mutex;
};

#if defined(LIBUSB_API_VERSION) && (LIBUSB_API_VERSION >= 0x01000102)

class LibUsbHotplugThread : public LibUsbThread {
 public:
 LibUsbHotplugThread(libusb_context *context,
 libusb_hotplug_callback_fn callback_fn,
 void *user_data);

 bool Init();

 void Shutdown();

 void OpenHandle() {}

 void CloseHandle(libusb_device_handle *handle);

 private:
 libusb_hotplug_callback_handle m_hotplug_handle;
 libusb_hotplug_callback_fn m_callback_fn;
 void *m_user_data;

 DISALLOW_COPY_AND_ASSIGN(LibUsbHotplugThread);
};

#endif

class LibUsbSimpleThread : public LibUsbThread {
 public:
 explicit LibUsbSimpleThread(libusb_context *context)
 : LibUsbThread(context),
 m_device_count(0) {
 }

 void OpenHandle();
 void CloseHandle(libusb_device_handle *handle);

 private:
 unsigned int m_device_count;

 DISALLOW_COPY_AND_ASSIGN(LibUsbSimpleThread);
};
} // namespace usbdmx
} // namespace plugin
} // namespace ola
#endif // PLUGINS_USBDMX_LIBUSBTHREAD_H_