/****************************************************************************
 * net/iob/iob_dump.c
 *
 *   Copyright (C) 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 nor the names of its contributors may 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.
 *
 ****************************************************************************/

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

#include <nuttx/config.h>

#include <stdint.h>
#include <debug.h>

#include <nuttx/net/iob.h>

#ifdef CONFIG_DEBUG

/****************************************************************************
 * Pre-processor definitions
 ****************************************************************************/

#ifndef MIN
#  define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Function: iob_dump
 *
 * Description:
 *   Dump the contents of a I/O buffer chain
 *
 ****************************************************************************/

void iob_dump(FAR const char *msg, FAR struct iob_s *iob, unsigned int len,
              unsigned int offset)
{
  FAR struct iob_s *head;
  uint8_t data[32];
  unsigned int maxlen;
  unsigned int nbytes;
  unsigned int lndx;
  unsigned int cndx;

  head = iob;
  lowsyslog(LOG_DEBUG, "%s: iob=%p pktlen=%d\n", msg, head, head->io_pktlen);

  /* Check if the offset is beyond the data in the I/O buffer chain */

  if (offset > head->io_pktlen)
    {
      ndbg("ERROR: offset is past the end of data: %u > %u\n",
           offset, head->io_pktlen);
      return;
    }

  /* Dump I/O buffer headers */

  for (; iob; iob = iob->io_flink)
    {
      lowsyslog(LOG_DEBUG, "  iob=%p len=%d offset=%d\n",
                iob, iob->io_len, iob->io_offset);
    }

  /* Get the amount of data to be displayed, limited by the amount that we
   * have beyond the offset.
   */

  maxlen = head->io_pktlen - offset;
  len = MIN(len, maxlen);

  /* Then beginning printing with the buffer containing the offset in groups
   * of 32 bytes.
   */

  for (lndx = 0; lndx < len; lndx += 32, offset += 32)
    {
      /* Copy 32-bytes into our local buffer from the current offset */

      nbytes = iob_copyout(data, head, 32, offset);

      /* Make sure that we have something to print */

      if (nbytes > 0)
        {
          lowsyslog(LOG_DEBUG, "  %04x: ", offset);

          for (cndx = 0; cndx < 32; cndx++)
            {
              if (cndx == 16)
                {
                  lowsyslog(LOG_DEBUG, " ");
                }

              if ((lndx + cndx) < len)
                {
                  lowsyslog(LOG_DEBUG, "%02x", data[cndx]);
                }
              else
                {
                  lowsyslog(LOG_DEBUG, "  ");
                }
            }

          lowsyslog(LOG_DEBUG, " ");
          for (cndx = 0; cndx < 32; cndx++)
            {
              if (cndx == 16)
                {
                  lowsyslog(LOG_DEBUG, " ");
                }

              if ((lndx + cndx) < len)
                {
                  if (data[cndx] >= 0x20 && data[cndx] < 0x7f)
                    {
                      lowsyslog(LOG_DEBUG, "%c", data[cndx]);
                    }
                  else
                    {
                      lowsyslog(LOG_DEBUG, ".");
                    }
                }
            }

          lowsyslog(LOG_DEBUG, "\n");
        }
    }
}

#endif /* CONFIG_DEBUG */