/*
   This file is part of GNUnet
   Copyright (C) 2012 GNUnet e.V.

   GNUnet is free software: you can redistribute it and/or modify it
   under the terms of the GNU Affero General Public License as published
   by the Free Software Foundation, either version 3 of the License,
   or (at your option) any later version.

   GNUnet 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
   Affero General Public License for more details.

   You should have received a copy of the GNU Affero General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */

/**
 * @file transport/gnunet-transport-wlan-receiver.c
 * @brief program to send via WLAN as much as possible (to test physical/theoretical throughput)
 * @author David Brodski
 */
#include "platform.h"
#include "gnunet_protocols.h"
#include "plugin_transport_wlan.h"

int
main(int argc, char *argv[])
{
  char msg_buf[65536];
  unsigned long long count;
  double bytes_per_s;
  time_t start;
  time_t akt;
  ssize_t ret;
  pid_t pid;
  int commpipe[2]; /* This holds the fd for the input & output of the pipe */

  if (2 != argc)
    {
      fprintf(stderr,
              "This program must be started with the interface name as argument.\n");
      fprintf(stderr,
              "Usage: %s interface-name\n"
              "e.g. %s mon0\n",
              argv[0],
              argv[0]);
      return 1;
    }

  /* Setup communication pipeline first */
  if (pipe(commpipe))
    {
      fprintf(stderr, "Failed to create pipe: %s\n", strerror(errno));
      exit(1);
    }

  /* Attempt to fork and check for errors */
  if ((pid = fork()) == -1)
    {
      fprintf(stderr, "Failed to fork: %s\n", strerror(errno));
      exit(1);
    }

  if (pid)
    {
      /* A positive (non-negative) PID indicates the parent process */
      if (0 != close(commpipe[1])) /* Close unused side of pipe (in side) */
        fprintf(stderr, "Failed to close fd: %s\n", strerror(errno));
      start = time(NULL);
      count = 0;
      while (1)
        {
          ret = read(commpipe[0], msg_buf, sizeof(msg_buf));
          if (0 > ret)
            {
              fprintf(stderr, "read failed: %s\n", strerror(errno));
              break;
            }
          count += ret;
          akt = time(NULL);
          if (akt - start > 30)
            {
              bytes_per_s = count / (akt - start);
              bytes_per_s /= 1024;
              printf("recv %f kb/s\n", bytes_per_s);
              start = akt;
              count = 0;
            }
        }
    }
  else
    {
      /* A zero PID indicates that this is the child process */
      (void)close(1);
      if (-1 ==
          dup2(commpipe[1], 1)) /* Replace stdin with the in side of the pipe */
        fprintf(stderr, "dup2 failed: %s\n", strerror(errno));
      (void)close(commpipe[0]); /* Close unused side of pipe (in side) */
      /* Replace the child fork with a new process */
      if (execlp("gnunet-helper-transport-wlan",
                 "gnunet-helper-transport-wlan",
                 argv[1],
                 NULL) == -1)
        {
          fprintf(stderr, "Could not start gnunet-helper-transport-wlan!");
          _exit(1);
        }
    }
  return 0;
}