nuttx-apps/include/graphics/nxwm/ckeyboard.hxx

/****************************************************************************
 * apps/include/graphics/nxwm/keyboard.hxx
 *
 *   Copyright (C) 2012, 2014 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX, NxWidgets, nor the names of its contributors
 *    me be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

#ifndef __NXWM_INCLUDE_CKEYBOARD_HXX
#define __NXWM_INCLUDE_CKEYBOARD_HXX

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/nx/nxglib.h>

#include <semaphore.h>
#include <pthread.h>

#include <nuttx/input/touchscreen.h>

#include "graphics/nxwidgets/cnxserver.hxx"
#include "graphics/nxwm/ccalibration.hxx"

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Implementation Classes
 ****************************************************************************/

namespace NxWM
{
  /**
   * The CKeyboard class provides the the calibration window and obtains
   * callibration data.
   */

  class CKeyboard
  {
  private:
    /**
     * The state of the listener thread.
     */

    enum EListenerState
    {
      LISTENER_NOTRUNNING = 0,  /**< The listener thread has not yet been started */
      LISTENER_STARTED,         /**< The listener thread has been started, but is not yet running */
      LISTENER_RUNNING,         /**< The listener thread is running normally */
      LISTENER_STOPREQUESTED,   /**< The listener thread has been requested to stop */
      LISTENER_TERMINATED,      /**< The listener thread terminated normally */
      LISTENER_FAILED           /**< The listener thread terminated abnormally */
    };

    /**
     * CKeyboard state data
     */

    NXWidgets::CNxServer        *m_server;  /**< The current NX server */
    int                          m_kbdFd;   /**< File descriptor of the opened keyboard device */
    pthread_t                    m_thread;  /**< The listener thread ID */
    volatile enum EListenerState m_state;   /**< The state of the listener thread */
    sem_t                        m_waitSem; /**< Used to synchronize with the listener thread */

    /**
     * Open the keyboard device.  Not very interesting for the case of
     * standard device but much more interesting for a USB keyboard device
     * that may disappear when the keyboard is disconnect but later reappear
     * when the keyboard is reconnected.  In this case, this function will
     * not return until the keyboard device was successfully opened (or
     * until an irrecoverable error occurs.
     *
     * Opens the keyboard device specified by CONFIG_NXWM_KEYBOARD_DEVPATH.
     *
     * @return On success, then method returns a valid file descriptor that
     * can be used to redirect stdin.  A negated errno value is returned
     * if an irrecoverable error occurs.
     */

    inline int open(void);

    /**
     * This is the heart of the keyboard listener thread.  It contains the
     * actual logic that listeners for and dispatches keyboard events to the
     * NX server.
     *
     * @return  If the session terminates gracefully (i.e., because >m_state
     * is no longer equal to  LISTENER_RUNNING, then method returns OK.  A
     * negated errno value is returned if an error occurs while reading from
     * the keyboard device.  A read error, depending upon the type of the
     * error, may simply indicate that a USB keyboard was removed and we
     * should wait for the keyboard to be connected.
     */

    inline int session(void);

    /**
     * The keyboard listener thread.  This is the entry point of a thread
     * that listeners for and dispatches keyboard events to the NX server.
     * It simply opens the keyboard device (using CKeyboard::open()) and
     * executes the session (via CKeyboard::session()).
     *
     * If an errors while reading from the keyboard device AND we are
     * configured to use a USB keyboard, then this function will wait for
     * the USB keyboard to be re-connected.
     *
     * @param arg.  The CKeyboard 'this' pointer cast to a void*.
     * @return This function normally does not return but may return NULL on
     *   error conditions.
     */

    static FAR void *listener(FAR void *arg);

  public:

    /**
     * CKeyboard Constructor
     *
     * @param server. An instance of the NX server.  This will be needed for
     *   injecting mouse data.
     */

    CKeyboard(NXWidgets::CNxServer *server);

    /**
     * CKeyboard Destructor
     */

    ~CKeyboard(void);

    /**
     * Start the keyboard listener thread.
     *
     * @return True if the keyboard listener thread was correctly started.
     */

    bool start(void);
  };
}

#endif // __NXWM_INCLUDE_CKEYBOARD_HXX