input.cc

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/*
 *  Copyright (C) 2007 Austin Robot Technology, Patrick Beeson
 *  Copyright (C) 2009, 2010 Austin Robot Technology, Jack O'Quin
 *  Copyright (C) 2015, Jack O'Quin
 *      Copyright (C) 2017, Robosense, Tony Zhang
 *
 *

 Copyright (C) 2010-2013 Austin Robot Technology, and others
 All rights reserved.


Modified BSD License:
--------------------

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

    * 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.

    * Neither the names of the University of Texas at Austin, nor
      Austin Robot Technology, nor the names of other 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.
 */

#include "input.h"

extern volatile sig_atomic_t flag;
namespace rslidar_driver
{
static const size_t packet_size = sizeof(rslidar_msgs::rslidarPacket().data);

// Input base class implementation

Input::Input(ros::NodeHandle private_nh, uint16_t port) : private_nh_(private_nh), port_(port)
{
  private_nh.param("device_ip", devip_str_, std::string(""));
  if (!devip_str_.empty())
    ROS_INFO_STREAM("Only accepting packets from IP address: " << devip_str_);
}

// InputSocket class implementation

InputSocket::InputSocket(ros::NodeHandle private_nh, uint16_t port) : Input(private_nh, port)
{
  sockfd_ = -1;

  if (!devip_str_.empty())
  {
    inet_aton(devip_str_.c_str(), &devip_);
  }

  ROS_INFO_STREAM("Opening UDP socket: port " << port);
  sockfd_ = socket(PF_INET, SOCK_DGRAM, 0);
  if (sockfd_ == -1)
  {
    perror("socket");  // TODO: ROS_ERROR errno
    return;
  }

  int opt = 1;
  if (setsockopt(sockfd_, SOL_SOCKET, SO_REUSEADDR, (const void*)&opt, sizeof(opt)))
  {
    perror("setsockopt error!\n");
    return;
  }

  sockaddr_in my_addr;                   // my address information
  memset(&my_addr, 0, sizeof(my_addr));  // initialize to zeros
  my_addr.sin_family = AF_INET;          // host byte order
  my_addr.sin_port = htons(port);        // port in network byte order
  my_addr.sin_addr.s_addr = INADDR_ANY;  // automatically fill in my IP

  if (bind(sockfd_, (sockaddr*)&my_addr, sizeof(sockaddr)) == -1)
  {
    perror("bind");  // TODO: ROS_ERROR errno
    return;
  }

  if (fcntl(sockfd_, F_SETFL, O_NONBLOCK | FASYNC) < 0)
  {
    perror("non-block");
    return;
  }
}

InputSocket::~InputSocket(void)
{
  (void)close(sockfd_);
}

int InputSocket::getPacket(rslidar_msgs::rslidarPacket* pkt, const double time_offset)
{
  double time1 = ros::Time::now().toSec();
  struct pollfd fds[1];
  fds[0].fd = sockfd_;
  fds[0].events = POLLIN;
  static const int POLL_TIMEOUT = 1000;  // one second (in msec)

  sockaddr_in sender_address;
  socklen_t sender_address_len = sizeof(sender_address);
  while (flag == 1)
  {
    // Receive packets that should now be available from the
    // socket using a blocking read.
    // poll() until input available
    do
    {
      int retval = poll(fds, 1, POLL_TIMEOUT);
      if (retval < 0)  // poll() error?
      {
        if (errno != EINTR)
          ROS_ERROR("poll() error: %s", strerror(errno));
        return 1;
      }
      if (retval == 0)  // poll() timeout?
      {
        ROS_WARN("Rslidar poll() timeout");

        char buffer_data[8] = "re-con";
        memset(&sender_address, 0, sender_address_len);          // initialize to zeros
        sender_address.sin_family = AF_INET;                     // host byte order
        sender_address.sin_port = htons(MSOP_DATA_PORT_NUMBER);  // port in network byte order, set any value
        sender_address.sin_addr.s_addr = devip_.s_addr;          // automatically fill in my IP
        sendto(sockfd_, &buffer_data, strlen(buffer_data), 0, (sockaddr*)&sender_address, sender_address_len);
        return 1;
      }
      if ((fds[0].revents & POLLERR) || (fds[0].revents & POLLHUP) || (fds[0].revents & POLLNVAL))  // device error?
      {
        ROS_ERROR("poll() reports Rslidar error");
        return 1;
      }
    } while ((fds[0].revents & POLLIN) == 0);
    ssize_t nbytes = recvfrom(sockfd_, &pkt->data[0], packet_size, 0, (sockaddr*)&sender_address, &sender_address_len);

    if (nbytes < 0)
    {
      if (errno != EWOULDBLOCK)
      {
        perror("recvfail");
        ROS_INFO("recvfail");
        return 1;
      }
    }
    else if ((size_t)nbytes == packet_size)
    {
      if (devip_str_ != "" && sender_address.sin_addr.s_addr != devip_.s_addr)
        continue;
      else
        break;  // done
    }

    ROS_DEBUG_STREAM("incomplete rslidar packet read: " << nbytes << " bytes");
  }
  if (flag == 0)
  {
    abort();
  }
  // Average the times at which we begin and end reading.  Use that to
  // estimate when the scan occurred. Add the time offset.
  double time2 = ros::Time::now().toSec();
  pkt->stamp = ros::Time((time2 + time1) / 2.0 + time_offset);

  return 0;
}

// InputPCAP class implementation

InputPCAP::InputPCAP(ros::NodeHandle private_nh, uint16_t port, double packet_rate, std::string filename,
                     bool read_once, bool read_fast, double repeat_delay)
  : Input(private_nh, port), packet_rate_(packet_rate), filename_(filename)
{
  pcap_ = NULL;
  empty_ = true;

  // get parameters using private node handle
  private_nh.param("read_once", read_once_, false);
  private_nh.param("read_fast", read_fast_, false);
  private_nh.param("repeat_delay", repeat_delay_, 0.0);

  if (read_once_)
    ROS_INFO("Read input file only once.");
  if (read_fast_)
    ROS_INFO("Read input file as quickly as possible.");
  if (repeat_delay_ > 0.0)
    ROS_INFO("Delay %.3f seconds before repeating input file.", repeat_delay_);

  // Open the PCAP dump file
  // ROS_INFO("Opening PCAP file \"%s\"", filename_.c_str());
  ROS_INFO_STREAM("Opening PCAP file " << filename_);
  if ((pcap_ = pcap_open_offline(filename_.c_str(), errbuf_)) == NULL)
  {
    ROS_FATAL("Error opening rslidar socket dump file.");
    return;
  }

  std::stringstream filter;
  if (devip_str_ != "")  // using specific IP?
  {
    filter << "src host " << devip_str_ << " && ";
  }
  filter << "udp dst port " << port;
  pcap_compile(pcap_, &pcap_packet_filter_, filter.str().c_str(), 1, PCAP_NETMASK_UNKNOWN);
}

InputPCAP::~InputPCAP(void)
{
  pcap_close(pcap_);
}

int InputPCAP::getPacket(rslidar_msgs::rslidarPacket* pkt, const double time_offset)
{
  struct pcap_pkthdr* header;
  const u_char* pkt_data;

  while (flag == 1)
  {
    int res;
    if ((res = pcap_next_ex(pcap_, &header, &pkt_data)) >= 0)
    {
      // Skip packets not for the correct port and from the
      // selected IP address.
      if (!devip_str_.empty() && (0 == pcap_offline_filter(&pcap_packet_filter_, header, pkt_data)))
        continue;

      // Keep the reader from blowing through the file.
      if (read_fast_ == false)
        packet_rate_.sleep();

      memcpy(&pkt->data[0], pkt_data + 42, packet_size);
      pkt->stamp = ros::Time::now();  // time_offset not considered here, as no
                                      // synchronization required
      empty_ = false;
      return 0;  // success
    }

    if (empty_)  // no data in file?
    {
      ROS_WARN("Error %d reading rslidar packet: %s", res, pcap_geterr(pcap_));
      return -1;
    }

    if (read_once_)
    {
      ROS_INFO("end of file reached -- done reading.");
      return -1;
    }

    if (repeat_delay_ > 0.0)
    {
      ROS_INFO("end of file reached -- delaying %.3f seconds.", repeat_delay_);
      usleep(rint(repeat_delay_ * 1000000.0));
    }

    ROS_DEBUG("replaying rslidar dump file");

    // I can't figure out how to rewind the file, because it
    // starts with some kind of header.  So, close the file
    // and reopen it with pcap.
    pcap_close(pcap_);
    pcap_ = pcap_open_offline(filename_.c_str(), errbuf_);
    empty_ = true;  // maybe the file disappeared?
  }                 // loop back and try again

  if (flag == 0)
  {
    abort();
  }
}
}