/*
 * Copyright 2009, Axel Dörfler, axeld@pinc-software.de.
 * Distributed under the terms of the MIT License.
 */

//!     A test app trying to reproduce bug #2197.

#include <errno.h>
#include <fcntl.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#include <sys/socket.h>


static int
open_tcp_socket()
{
        int fd = socket(AF_INET, SOCK_STREAM, 0);
        if (fd < 0)
                return -1;

        // make it non-blocking
        fcntl(fd, F_SETFL, O_NONBLOCK);

        return fd;
}


static void
init_sockaddr(struct sockaddr_in& address, unsigned ipAddress, unsigned port)
{
        memset(&address, 0, sizeof(sockaddr_in));
        address.sin_family = AF_INET;
        address.sin_port = htons(port);
        address.sin_addr.s_addr = htonl(ipAddress);
}


static int
tcp_pair(int pair[])
{
        pair[0] = pair[1] = -1;

        int listenSocket = open_tcp_socket();
        if (listenSocket < 0)
                return -1;

        sockaddr_in listenAddress;
        sockaddr_in peerAddress;
        sockaddr_in address;
        socklen_t length;
        init_sockaddr(listenAddress, INADDR_LOOPBACK, 0);

        if (bind(listenSocket, (sockaddr*)&listenAddress, sizeof(sockaddr_in)) != 0)
                goto error;

        length = sizeof(sockaddr_in);
        if (getsockname(listenSocket, (sockaddr*)&listenAddress, &length) != 0)
                goto error;

        if (listen(listenSocket, 5) != 0)
                goto error;

        pair[0] = open_tcp_socket();
        if (pair[0] < 0)
                goto error;

        init_sockaddr(address, INADDR_LOOPBACK, ntohs(listenAddress.sin_port));

        if (connect(pair[0], (sockaddr*)&address, sizeof(sockaddr_in)) != 0
                && errno != EINPROGRESS)
                goto error;

        if (errno == EINPROGRESS) {
                struct timeval tv;
                tv.tv_sec = 100000;
                tv.tv_usec = 0;
                fd_set set;
                FD_ZERO(&set);
                FD_SET(pair[0], &set);
                if (select(pair[0] + 1, NULL, &set, NULL, &tv) < 0)
                        fprintf(stderr, "write select() failed: %s\n", strerror(errno));
        }

        length = sizeof(sockaddr_in);
        if (getsockname(pair[0], (sockaddr*)&address, &length) != 0)
                goto error;

        while (true) {
                pair[1] = accept(listenSocket, (sockaddr*)&peerAddress, &length);
                if (pair[1] >= 0)
                        break;

                if (errno != EAGAIN && errno != EWOULDBLOCK && errno != ETIMEDOUT)
                        goto error;

                struct timeval tv;
                tv.tv_sec = 100000;
                tv.tv_usec = 0;
                fd_set set;
                FD_ZERO(&set);
                FD_SET(listenSocket, &set);
                if (select(listenSocket + 1, &set, NULL, NULL, &tv) < 0)
                        fprintf(stderr, "read select() failed: %s\n", strerror(errno));
        }

        if (peerAddress.sin_port != address.sin_port)
                goto error;

        close(listenSocket);
    return 0;

error:
        close(listenSocket);
        for (int i = 0; i < 2; i++) {
                if (pair[i] >= 0)
                        close(pair[i]);
        }

    return -1;
}


int
main(int argc, char** argv)
{
        int pair[2];
        if (tcp_pair(pair) == 0) {
                close(pair[0]);
                close(pair[1]);
        } else
                fprintf(stderr, "pair failed: %s\n", strerror(errno));
        return 0;
}