/****************************************************************************
 * apps/examples/nettest/nettest_server.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * 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 "config.h"

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include <arpa/inet.h>

#include "nettest.h"

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

void nettest_server(void)
{
#ifdef CONFIG_EXAMPLES_NETTEST_IPv6
  struct sockaddr_in6 myaddr;
#else
  struct sockaddr_in myaddr;
#endif
#ifdef NETTEST_HAVE_SOLINGER
  struct linger ling;
#endif
  char *buffer;
  int listensd;
  int acceptsd;
  socklen_t addrlen;
  int nbytesread;
#ifndef CONFIG_EXAMPLES_NETTEST_PERFORMANCE
  int totalbytesread;
  int nbytessent;
  int ch;
  int i;
#endif
  int optval;

  /* Allocate a BIG buffer */

  buffer = malloc(2*SENDSIZE);
  if (!buffer)
    {
      printf("server: failed to allocate buffer\n");
      exit(1);
    }

  /* Create a new TCP socket */

  listensd = socket(PF_INETX, SOCK_STREAM, 0);
  if (listensd < 0)
    {
      printf("server: socket failure: %d\n", errno);
      goto errout_with_buffer;
    }

  /* Set socket to reuse address */

  optval = 1;
  if (setsockopt(listensd, SOL_SOCKET, SO_REUSEADDR,
                 &optval, sizeof(int)) < 0)
    {
      printf("server: setsockopt SO_REUSEADDR failure: %d\n", errno);
      goto errout_with_listensd;
    }

  /* Bind the socket to a local address */

#ifdef CONFIG_EXAMPLES_NETTEST_IPv6

  myaddr.sin6_family     = AF_INET6;
  myaddr.sin6_port       = HTONS(CONFIG_EXAMPLES_NETTEST_SERVER_PORTNO);
#if defined(CONFIG_EXAMPLES_NETTEST_LOOPBACK) && !defined(NET_LOOPBACK)
  memcpy(myaddr.sin6_addr.s6_addr16,
         g_nettestserver_ipv6, 8 * sizeof(uint16_t));
#else
  memset(myaddr.sin6_addr.s6_addr16, 0, 8 * sizeof(uint16_t));
#endif
  addrlen = sizeof(struct sockaddr_in6);

  printf("Binding to Address: %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
         myaddr.sin6_addr.s6_addr16[0], myaddr.sin6_addr.s6_addr16[1],
         myaddr.sin6_addr.s6_addr16[2], myaddr.sin6_addr.s6_addr16[3],
         myaddr.sin6_addr.s6_addr16[4], myaddr.sin6_addr.s6_addr16[5],
         myaddr.sin6_addr.s6_addr16[6], myaddr.sin6_addr.s6_addr16[7]);
#else
  myaddr.sin_family      = AF_INET;
  myaddr.sin_port        = HTONS(CONFIG_EXAMPLES_NETTEST_SERVER_PORTNO);

#if defined(CONFIG_EXAMPLES_NETTEST_LOOPBACK) && !defined(NET_LOOPBACK)
  myaddr.sin_addr.s_addr = (in_addr_t)g_nettestserver_ipv4;
#else
  myaddr.sin_addr.s_addr = INADDR_ANY;
#endif
  addrlen = sizeof(struct sockaddr_in);

  printf("Binding to IPv4 Address: %08lx\n",
         (unsigned long)myaddr.sin_addr.s_addr);
#endif

  if (bind(listensd, (struct sockaddr *)&myaddr, addrlen) < 0)
    {
      printf("server: bind failure: %d\n", errno);
      goto errout_with_listensd;
    }

  /* Listen for connections on the bound TCP socket */

  if (listen(listensd, 5) < 0)
    {
      printf("server: listen failure %d\n", errno);
      goto errout_with_listensd;
    }

  /* Accept only one connection */

  printf("server: Accepting connections on port %d\n",
         CONFIG_EXAMPLES_NETTEST_SERVER_PORTNO);
#ifdef __NuttX__
  acceptsd = accept4(listensd, (struct sockaddr *)&myaddr, &addrlen,
                     SOCK_CLOEXEC);
#else
  acceptsd = accept(listensd, (struct sockaddr *)&myaddr, &addrlen);
#endif
  if (acceptsd < 0)
    {
      printf("server: accept failure: %d\n", errno);
      goto errout_with_listensd;
    }

  printf("server: Connection accepted -- receiving\n");

  /* Configure to "linger" until all data is sent when the socket is closed */

#ifdef NETTEST_HAVE_SOLINGER
  ling.l_onoff  = 1;
  ling.l_linger = 30;     /* timeout is seconds */

  if (setsockopt(acceptsd, SOL_SOCKET, SO_LINGER,
                 &ling, sizeof(struct linger)) < 0)
    {
      printf("server: setsockopt SO_LINGER failure: %d\n", errno);
      goto errout_with_acceptsd;
    }
#endif

#ifdef CONFIG_EXAMPLES_NETTEST_PERFORMANCE
  /* Then receive data forever */

  for (; ; )
    {
      nbytesread = recv(acceptsd, buffer, 2*SENDSIZE, 0);
      if (nbytesread < 0)
        {
          printf("server: recv failed: %d\n", errno);
          goto errout_with_acceptsd;
        }
      else if (nbytesread == 0)
        {
          printf("server: The client broke the connection\n");
          goto errout_with_acceptsd;
        }

      printf("Received %d bytes\n", nbytesread);
    }
#else

  /* Receive canned message */

  totalbytesread = 0;
  while (totalbytesread < SENDSIZE)
    {
      printf("server: Reading...\n");
      nbytesread = recv(acceptsd, &buffer[totalbytesread],
                        2 * SENDSIZE - totalbytesread, 0);
      if (nbytesread < 0)
        {
          printf("server: recv failed: %d\n", errno);
          goto errout_with_acceptsd;
        }
      else if (nbytesread == 0)
        {
          printf("server: The client broke the connection\n");
          goto errout_with_acceptsd;
        }

      totalbytesread += nbytesread;
      printf("server: Received %d of %d bytes\n", totalbytesread, SENDSIZE);
    }

  /* Verify the message */

  if (totalbytesread != SENDSIZE)
    {
      printf("server: Received %d / Expected %d bytes\n",
             totalbytesread, SENDSIZE);
      goto errout_with_acceptsd;
    }

  ch = 0x20;
  for (i = 0; i < SENDSIZE; i++ )
    {
      if (buffer[i] != ch)
        {
          printf("server: Byte %d is %02x / Expected %02x\n",
                 i, buffer[i], ch);
          goto errout_with_acceptsd;
        }

      if (++ch > 0x7e)
        {
          ch = 0x20;
        }
    }

  /* Then send the same data back to the client */

  printf("server: Sending %d bytes\n", totalbytesread);
  nbytessent = send(acceptsd, buffer, totalbytesread, 0);
  if (nbytessent <= 0)
    {
      printf("server: send failed: %d\n", errno);
      goto errout_with_acceptsd;
    }

  printf("server: Sent %d bytes\n", nbytessent);

  /* If this platform only does abortive disconnects, then wait a bit to get
   * the client side a change to receive the data.
   */

#if 1 /* Do it for all platforms */
  printf("server: Wait before closing\n");
  sleep(2);
#endif

  printf("server: Terminating\n");
  close(listensd);
  close(acceptsd);
  free(buffer);
  return;
#endif

errout_with_acceptsd:
  close(acceptsd);

errout_with_listensd:
  close(listensd);

errout_with_buffer:
  free(buffer);
  exit(1);
}
