#ifndef _NETINET_TCP_H
#define _NETINET_TCP_H

#include <features.h>

#define TCP_NODELAY 1
#define TCP_MAXSEG 2
#define TCP_CORK 3
#define TCP_KEEPIDLE 4
#define TCP_KEEPINTVL 5
#define TCP_KEEPCNT 6
#define TCP_SYNCNT 7
#define TCP_LINGER2 8
#define TCP_DEFER_ACCEPT 9
#define TCP_WINDOW_CLAMP 10
#define TCP_INFO 11
#define TCP_QUICKACK 12
#define TCP_CONGESTION 13
#define TCP_MD5SIG 14
#define TCP_THIN_LINEAR_TIMEOUTS 16
#define TCP_THIN_DUPACK 17
#define TCP_USER_TIMEOUT 18
#define TCP_REPAIR 19
#define TCP_REPAIR_QUEUE 20
#define TCP_QUEUE_SEQ 21
#define TCP_REPAIR_OPTIONS 22
#define TCP_FASTOPEN 23
#define TCP_TIMESTAMP 24
#define TCP_NOTSENT_LOWAT 25
#define TCP_CC_INFO 26
#define TCP_SAVE_SYN 27
#define TCP_SAVED_SYN 28

#define TCP_ESTABLISHED 1
#define TCP_SYN_SENT 2
#define TCP_SYN_RECV 3
#define TCP_FIN_WAIT1 4
#define TCP_FIN_WAIT2 5
#define TCP_TIME_WAIT 6
#define TCP_CLOSE 7
#define TCP_CLOSE_WAIT 8
#define TCP_LAST_ACK 9
#define TCP_LISTEN 10
#define TCP_CLOSING 11

#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
#define TCPOPT_EOL 0
#define TCPOPT_NOP 1
#define TCPOPT_MAXSEG 2
#define TCPOPT_WINDOW 3
#define TCPOPT_SACK_PERMITTED 4
#define TCPOPT_SACK 5
#define TCPOPT_TIMESTAMP 8
#define TCPOLEN_SACK_PERMITTED 2
#define TCPOLEN_WINDOW 3
#define TCPOLEN_MAXSEG 4
#define TCPOLEN_TIMESTAMP 10

#define SOL_TCP 6

#include <sys/types.h>
#include <sys/socket.h>
#include <stdint.h>
#include <endian.h>

typedef uint32_t tcp_seq;

#define TH_FIN 0x01
#define TH_SYN 0x02
#define TH_RST 0x04
#define TH_PUSH 0x08
#define TH_ACK 0x10
#define TH_URG 0x20

struct tcphdr {
#ifdef _GNU_SOURCE
#ifdef __GNUC__
  __extension__
#endif
      union {
    struct {
      uint16_t source;
      uint16_t dest;
      uint32_t seq;
      uint32_t ack_seq;
#if __BYTE_ORDER == __LITTLE_ENDIAN
      uint16_t res1 : 4;
      uint16_t doff : 4;
      uint16_t fin : 1;
      uint16_t syn : 1;
      uint16_t rst : 1;
      uint16_t psh : 1;
      uint16_t ack : 1;
      uint16_t urg : 1;
      uint16_t res2 : 2;
#else
      uint16_t doff : 4;
      uint16_t res1 : 4;
      uint16_t res2 : 2;
      uint16_t urg : 1;
      uint16_t ack : 1;
      uint16_t psh : 1;
      uint16_t rst : 1;
      uint16_t syn : 1;
      uint16_t fin : 1;
#endif
      uint16_t window;
      uint16_t check;
      uint16_t urg_ptr;
    };
    struct {
#endif

      uint16_t th_sport;
      uint16_t th_dport;
      uint32_t th_seq;
      uint32_t th_ack;
#if __BYTE_ORDER == __LITTLE_ENDIAN
      uint8_t th_x2 : 4;
      uint8_t th_off : 4;
#else
  uint8_t th_off : 4;
  uint8_t th_x2 : 4;
#endif
      uint8_t th_flags;
      uint16_t th_win;
      uint16_t th_sum;
      uint16_t th_urp;

#ifdef _GNU_SOURCE
    };
  };
#endif
};
#endif

#ifdef _GNU_SOURCE
#define TCPI_OPT_TIMESTAMPS 1
#define TCPI_OPT_SACK 2
#define TCPI_OPT_WSCALE 4
#define TCPI_OPT_ECN 8

#define TCP_CA_Open 0
#define TCP_CA_Disorder 1
#define TCP_CA_CWR 2
#define TCP_CA_Recovery 3
#define TCP_CA_Loss 4

struct tcp_info {
  uint8_t tcpi_state;
  uint8_t tcpi_ca_state;
  uint8_t tcpi_retransmits;
  uint8_t tcpi_probes;
  uint8_t tcpi_backoff;
  uint8_t tcpi_options;
  uint8_t tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
  uint32_t tcpi_rto;
  uint32_t tcpi_ato;
  uint32_t tcpi_snd_mss;
  uint32_t tcpi_rcv_mss;
  uint32_t tcpi_unacked;
  uint32_t tcpi_sacked;
  uint32_t tcpi_lost;
  uint32_t tcpi_retrans;
  uint32_t tcpi_fackets;
  uint32_t tcpi_last_data_sent;
  uint32_t tcpi_last_ack_sent;
  uint32_t tcpi_last_data_recv;
  uint32_t tcpi_last_ack_recv;
  uint32_t tcpi_pmtu;
  uint32_t tcpi_rcv_ssthresh;
  uint32_t tcpi_rtt;
  uint32_t tcpi_rttvar;
  uint32_t tcpi_snd_ssthresh;
  uint32_t tcpi_snd_cwnd;
  uint32_t tcpi_advmss;
  uint32_t tcpi_reordering;
  uint32_t tcpi_rcv_rtt;
  uint32_t tcpi_rcv_space;
  uint32_t tcpi_total_retrans;
  uint64_t tcpi_pacing_rate;
  uint64_t tcpi_max_pacing_rate;
  uint64_t tcpi_bytes_acked;
  uint64_t tcpi_bytes_received;
  uint32_t tcpi_segs_out;
  uint32_t tcpi_segs_in;
};

#define TCP_MD5SIG_MAXKEYLEN 80

struct tcp_md5sig {
  struct sockaddr_storage tcpm_addr;
  uint16_t __tcpm_pad1;
  uint16_t tcpm_keylen;
  uint32_t __tcpm_pad2;
  uint8_t tcpm_key[TCP_MD5SIG_MAXKEYLEN];
};

#endif

#endif