text: /****************************************************************************
   * graphics/nxterm/nxterm_driver.c
   *
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.  The
   * ASF licenses this file to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance with the
   * License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
   * License for the specific language governing permissions and limitations
   * under the License.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <sys/types.h>
  #include <stdbool.h>
  #include <string.h>
  #include <fcntl.h>
  #include <assert.h>
  #include <errno.h>
  #include <debug.h>
  
  #include <nuttx/fs/fs.h>
  
  #include "nxterm.h"
  
  /****************************************************************************
   * Private Function Prototypes
   ****************************************************************************/
  
  static int     nxterm_open(FAR struct file *filep);
  static int     nxterm_close(FAR struct file *filep);
  static ssize_t nxterm_write(FAR struct file *filep, FAR const char *buffer,
                   size_t buflen);
  static int     nxterm_ioctl(FAR struct file *filep, int cmd,
                              unsigned long arg);
  #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
  static int     nxterm_unlink(FAR struct inode *inode);
  #endif
  
  /****************************************************************************
   * Public Data
   ****************************************************************************/
  
  /* This is the common NX driver file operations */
  
  #ifdef CONFIG_NXTERM_NXKBDIN
  
  const struct file_operations g_nxterm_drvrops =
  {
    nxterm_open,    /* open */
    nxterm_close,   /* close */
    nxterm_read,    /* read */
    nxterm_write,   /* write */
    NULL,           /* seek */
    nxterm_ioctl,   /* ioctl */
    nxterm_poll     /* poll */
  #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
    , nxterm_unlink /* unlink */
  #endif
  };
  
  #else /* CONFIG_NXTERM_NXKBDIN */
  
  const struct file_operations g_nxterm_drvrops =
  {
    nxterm_open,    /* open */
    nxterm_close,   /* close */
    NULL,           /* read */
    nxterm_write,   /* write */
    NULL,           /* seek */
    nxterm_ioctl,   /* ioctl */
    NULL            /* poll */
  #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
    , nxterm_unlink /* unlink */
  #endif
  };
  
  #endif /* CONFIG_NXTERM_NXKBDIN */
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nxterm_open
   ****************************************************************************/
  
  static int nxterm_open(FAR struct file *filep)
  {
    FAR struct inode         *inode = filep->f_inode;
    FAR struct nxterm_state_s *priv = inode->i_private;
  
    DEBUGASSERT(filep && filep->f_inode);
  
    /* Get the driver structure from the inode */
  
    inode = filep->f_inode;
    priv  = (FAR struct nxterm_state_s *)inode->i_private;
    DEBUGASSERT(priv);
  
    /* Verify that the driver is opened for write-only access */
  
  #ifndef CONFIG_NXTERM_NXKBDIN
    if ((filep->f_oflags & O_RDOK) != 0)
      {
        gerr("ERROR: Attempted open with read access\n");
        return -EACCES;
      }
  #endif
  
  #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
    /* Increment the count of open file reference */
  
    DEBUGASSERT(priv->orefs != UINT8_MAX);
    priv->orefs++;
  #endif
  
    /* Assign the driver structure to the file */
  
    filep->f_priv = priv;
    return OK;
  }
  
  /****************************************************************************
   * Name: nxterm_close
   ****************************************************************************/
  
  static int nxterm_close(FAR struct file *filep)
  {
  #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
    FAR struct nxterm_state_s *priv;
    int ret;
  
    /* Recover our private state structure */
  
    DEBUGASSERT(filep != NULL && filep->f_priv != NULL);
    priv = (FAR struct nxterm_state_s *)filep->f_priv;
  
    /* Get exclusive access */
  
    ret = nxterm_semwait(priv);
    if (ret < 0)
      {
        return ret;
      }
  
    /* Has the driver been unlinked?  Was this the last open references to the
     * terminal driver?
     */
  
    DEBUGASSERT(priv->orefs > 0);
    if (priv->unlinked && priv->orefs <= 1)
      {
        /* Yes.. Unregister the terminal device */
  
        nxterm_unregister(priv);
      }
    else
      {
        /* No.. Just decrement the count of open file references */
  
        priv->orefs--;
      }
  
    nxterm_sempost(priv);
  #endif
  
    return OK;
  }
  
  /****************************************************************************
   * Name: nxterm_write
   ****************************************************************************/
  
  static ssize_t nxterm_write(FAR struct file *filep, FAR const char *buffer,
                             size_t buflen)
  {
    FAR struct nxterm_state_s *priv;
    enum nxterm_vt100state_e state;
    ssize_t remaining;
    char ch;
    int ret;
  
    /* Recover our private state structure */
  
    DEBUGASSERT(filep != NULL && filep->f_priv != NULL);
    priv = (FAR struct nxterm_state_s *)filep->f_priv;
  
    /* Get exclusive access */
  
    ret = nxterm_semwait(priv);
    if (ret < 0)
      {
        return ret;
      }
  
    /* Hide the cursor while we update the display */
  
    nxterm_hidecursor(priv);
  
    /* Loop writing each character to the display */
  
    for (remaining = (ssize_t)buflen; remaining > 0; remaining--)
      {
        /* Get the next character from the user buffer */
  
        ch = *buffer++;
  
        /* Check if this character is part of a VT100 escape sequence */
  
        do
          {
            /* Is the character part of a VT100 escape sequnce? */
  
            state = nxterm_vt100(priv, ch);
            switch (state)
              {
                /* Character is not part of a VT100 escape sequence (and no
                 * characters are buffer.
                 */
  
                default:
                case VT100_NOT_CONSUMED:
                  {
                    /* We can output the character to the window */
  
                    nxterm_putc(priv, (uint8_t)ch);
                  }
                break;
  
              /* The full VT100 escape sequence was processed (and the new
               * character was consumed)
               */
  
              case VT100_PROCESSED:
  
              /* Character was consumed as part of the VT100 escape processing
               * (but the escape sequence is still incomplete.
               */
  
              case VT100_CONSUMED:
                {
                  /* Do nothing... the VT100 logic owns the character */
                }
                break;
  
              /* Invalid/unsupported character in escape sequence */
  
              case VT100_ABORT:
                {
                  int i;
  
                  /* Add the first unhandled character to the window */
  
                  nxterm_putc(priv, (uint8_t)priv->seq[0]);
  
                  /* Move all buffer characters down one */
  
                  for (i = 1; i < priv->nseq; i++)
                    {
                      priv->seq[i - 1] = priv->seq[i];
                    }
  
                  priv->nseq--;
  
                  /* Then loop again and check if what remains is part of a
                   * VT100 escape sequence.  We could speed this up by
                   * checking if priv->seq[0] == ASCII_ESC.
                   */
                }
                break;
              }
          }
        while (state == VT100_ABORT);
      }
  
    /* Show the cursor at its new position */
  
    nxterm_showcursor(priv);
    nxterm_sempost(priv);
    return (ssize_t)buflen;
  }
  
  /****************************************************************************
   * Name: nxterm_ioctl
   ****************************************************************************/
  
  static int nxterm_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
  {
    /* NOTE:  We don't need driver context here because the NXTERM handle
     * provided within each of the NXTERM IOCTL command data.  Mutual
     * exclusion is similar managed by the IOCTL cmmand handler.
     *
     * This permits the IOCTL to be called in abnormal context (such as
     * from boardctl())
     */
  
    return nxterm_ioctl_tap(cmd, arg);
  }
  
  /****************************************************************************
   * Name: nxterm_unlink
   ****************************************************************************/
  
  #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
  static int nxterm_unlink(FAR struct inode *inode)
  {
    FAR struct nxterm_state_s *priv;
    int ret;
  
    DEBUGASSERT(inode != NULL && inode->i_private != NULL);
    priv = inode->i_private;
  
    /* Get exclusive access */
  
    ret = nxterm_semwait(priv);
    if (ret < 0)
      {
        return ret;
      }
  
    /* Are there open references to the terminal driver? */
  
    if (priv->orefs > 0)
      {
        /* Yes.. Just mark the driver unlinked.  Resources will be cleaned up
         * when the final reference is close.
         */
  
        priv->unlinked = true;
      }
    else
      {
        /* No.. Unregister the terminal device now */
  
        nxterm_unregister(priv);
      }
  
    nxterm_sempost(priv);
    return OK;
  }
  #endif
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nxterm_ioctl_tap
   *
   * Description:
   *   Execute an NXTERM IOCTL command from an external caller.
   *
   * NOTE:  We don't need driver context here because the NXTERM handle
   * provided within each of the NXTERM IOCTL command data.  Mutual
   * exclusion is similar managed by the IOCTL cmmand handler.
   *
   * This permits the IOCTL to be called in abnormal context (such as
   * from boardctl())
   *
   ****************************************************************************/
  
  int nxterm_ioctl_tap(int cmd, uintptr_t arg)
  {
    int ret;
  
    switch (cmd)
      {
        /* CMD:           NXTERMIOC_NXTERM_REDRAW
         * DESCRIPTION:   Re-draw a portion of the NX console.  This function
         *                should be called from the appropriate window callback
         *                logic.
         * ARG:           A reference readable instance of struct
         *                nxtermioc_redraw_s
         * CONFIGURATION: CONFIG_NXTERM
         */
  
         case NXTERMIOC_NXTERM_REDRAW:
           {
             FAR struct nxtermioc_redraw_s *redraw =
               (FAR struct nxtermioc_redraw_s *)((uintptr_t)arg);
  
             nxterm_redraw(redraw->handle, &redraw->rect, redraw->more);
             ret = OK;
           }
           break;
  
        /* CMD:           NXTERMIOC_NXTERM_KBDIN
         * DESCRIPTION:   Provide NxTerm keyboard input to NX.
         * ARG:           A reference readable instance of struct
         *                nxtermioc_kbdin_s
         * CONFIGURATION: CONFIG_NXTERM_NXKBDIN
         */
  
         case NXTERMIOC_NXTERM_KBDIN:
           {
  #ifdef CONFIG_NXTERM_NXKBDIN
             FAR struct nxtermioc_kbdin_s *kbdin =
               (FAR struct nxtermioc_kbdin_s *)((uintptr_t)arg);
  
             nxterm_kbdin(kbdin->handle, kbdin->buffer, kbdin->buflen);
             ret = OK;
  #else
             ret = -ENOSYS;
  #endif
           }
           break;
  
        /* CMD:           NXTERMIOC_NXTERM_RESIZE
         * DESCRIPTION:   Inform NxTerm keyboard the the size of the window has
         *                changed
         * ARG:           A reference readable instance of struct
         *                nxtermioc_resize_s
         * CONFIGURATION: CONFIG_NXTERM
         */
  
         case NXTERMIOC_NXTERM_RESIZE:
           {
             FAR struct nxtermioc_resize_s *resize =
               (FAR struct nxtermioc_resize_s *)((uintptr_t)arg);
  
             ret = nxterm_resize(resize->handle, &resize->size);
           }
           break;
  
        default:
          ret = -ENOTTY;
          break;
      }
  
    return ret;
  }
  