/*
 * Copyright (c) 2009, The Regents of the University of California, through
 * Lawrence Berkeley National Laboratory (subject to receipt of any required
 * approvals from the U.S. Dept. of Energy).  All rights reserved.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netdb.h>
#include <netinet/tcp.h>
#include <sys/time.h>
#include <sys/select.h>

#include "iperf.h"
#include "iperf_api.h"
#include "iperf_tcp.h"
#include "iperf_error.h"
#include "net.h"


/* iperf_tcp_recv
 *
 * receives the data for TCP
 */
int
iperf_tcp_recv(struct iperf_stream *sp)
{
    int result = 0;
    int size = sp->settings->blksize;

    result = Nread(sp->socket, sp->buffer, size, Ptcp);

    if (result < 0) {
        return (-1);
    }

    sp->result->bytes_received += result;
    sp->result->bytes_received_this_interval += result;

    return (result);
}


/* iperf_tcp_send 
 *
 * sends the data for TCP
 */
int
iperf_tcp_send(struct iperf_stream *sp)
{
    int result;
    int size = sp->settings->blksize;

    result = Nwrite(sp->socket, sp->buffer, size, Ptcp);

    if (result < 0) {
        return (-1);
    }

    sp->result->bytes_sent += result;
    sp->result->bytes_sent_this_interval += result;

    return (result);
}


/* iperf_tcp_accept
 *
 * accept a new TCP stream connection
 */
int
iperf_tcp_accept(struct iperf_test * test)
{
    int     s;
    int     rbuf = ACCESS_DENIED;
    char    cookie[COOKIE_SIZE];
    socklen_t len;
    struct sockaddr_in addr;

    len = sizeof(addr);
    if ((s = accept(test->listener, (struct sockaddr *) &addr, &len)) < 0) {
        i_errno = IESTREAMCONNECT;
        return (-1);
    }

    if (Nread(s, cookie, COOKIE_SIZE, Ptcp) < 0) {
        i_errno = IERECVCOOKIE;
        return (-1);
    }

    if (strcmp(test->cookie, cookie) != 0) {
        if (Nwrite(s, &rbuf, sizeof(char), Ptcp) < 0) {
            i_errno = IESENDMESSAGE;
            return (-1);
        }
        close(s);
    }

    return (s);
}


/* iperf_tcp_listen
 *
 * start up a listener for TCP stream connections
 */
int
iperf_tcp_listen(struct iperf_test *test)
{
    int s, opt;
    struct sockaddr_in sa;
    s = test->listener;

    if (test->no_delay || test->settings->mss) {
        FD_CLR(s, &test->read_set);
        close(s);
        if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
            i_errno = IESTREAMLISTEN;
            return (-1);
        }
        if (test->no_delay) {
            opt = 1;
            if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt)) < 0) {
                i_errno = IESETNODELAY;
                return (-1);
            }
            printf("      TCP NODELAY: on\n");
        }
        // XXX: Setting MSS is very buggy!
        if ((opt = test->settings->mss)) {
            if (setsockopt(s, IPPROTO_TCP, TCP_MAXSEG, &opt, sizeof(opt)) < 0) {
                i_errno = IESETMSS;
                return (-1);
            }
            printf("      TCP MSS: %d\n", opt);
        }
        opt = 1;
        if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)) < 0) {
            i_errno = IEREUSEADDR;
            return (-1);
        }

        memset(&sa, 0, sizeof(sa));
        sa.sin_family = AF_INET;
        sa.sin_addr.s_addr = htonl(INADDR_ANY);
        sa.sin_port = htons(test->server_port);

        if (bind(s, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
            close(s);
            i_errno = IESTREAMLISTEN;
            return (-1);
        }

        if (listen(s, 5) < 0) {
            i_errno = IESTREAMLISTEN;
            return (-1);
        }

        test->listener = s;
    }
    
    return (s);
}


/* iperf_tcp_connect
 *
 * connect to a TCP stream listener
 */
int
iperf_tcp_connect(struct iperf_test *test)
{
    int s, opt;
    struct sockaddr_in sa;
    struct hostent *hent;

    if ((hent = gethostbyname(test->server_hostname)) == 0) {
        i_errno = IESTREAMCONNECT;
        return (-1);
    }
    if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
        i_errno = IESTREAMCONNECT;
        return (-1);
    }

    memset(&sa, 0, sizeof(sa));
    sa.sin_family = AF_INET;
    memcpy(&sa.sin_addr.s_addr, hent->h_addr, sizeof(sa.sin_addr.s_addr));
    sa.sin_port = htons(test->server_port);

    /* Set TCP options */
    if (test->no_delay) {
        opt = 1;
        if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt)) < 0) {
            i_errno = IESETNODELAY;
            return (-1);
        }
    }
    if ((opt = test->settings->mss)) {
        if (setsockopt(s, IPPROTO_TCP, TCP_MAXSEG, &opt, sizeof(opt)) < 0) {
            i_errno = IESETMSS;
            return (-1);
        }
    }

    if (connect(s, (struct sockaddr *) &sa, sizeof(sa)) < 0 && errno != EINPROGRESS) {
        i_errno = IESTREAMCONNECT;
        return (-1);
    }

    /* Send cookie for verification */
    if (Nwrite(s, test->cookie, COOKIE_SIZE, Ptcp) < 0) {
        i_errno = IESENDCOOKIE;
        return (-1);
    }

    return (s);
}