/*      $OpenBSD: server-tcp.c,v 1.4 2021/07/06 11:50:34 bluhm Exp $    */

/*
 * Copyright (c) 2020 Alexander Bluhm <bluhm@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

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

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

#include "util.h"

void __dead usage(void);
int listen_socket(const char *, const char *);
int accept_socket(int);

void __dead
usage(void)
{
        fprintf(stderr, "server-tcp [-r rcvmsg] [-s sndmsg] host port\n"
        "    -E         wait for EOF\n"
        "    -N         shutdown write\n"
        "    -r rcvmsg  receive from client and check message\n"
        "    -s sndmsg  send message to client\n");
        exit(2);
}

int
main(int argc, char *argv[])
{
        const char *host, *port;
        struct task todo[100];
        size_t tlen = 0;
        int ch, s;

        while ((ch = getopt(argc, argv, "ENr:s:")) != -1) {
                switch (ch) {
                case 'E':
                case 'N':
                case 'r':
                case 's':
                        if (tlen >= sizeof(todo) / sizeof(todo[0]))
                                errx(1, "too many tasks");
                        task_enqueue(&todo[tlen], ch, optarg);
                        tlen++;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;

        if (argc == 2) {
                host = argv[0];
                port = argv[1];
        } else {
                usage();
        }

        alarm(10);
        s = listen_socket(host, port);
        print_sockname(s);

        switch (fork()) {
        case -1:
                err(1, "fork");
        case 0:
                /* child continues, set timer for new process */
                alarm(10);
                break;
        default:
                /* parent exits and test runs in parallel */
                _exit(0);
        }

        s = accept_socket(s);
        task_run(s, todo, tlen);
        if (close(s) == -1)
                err(1, "close");

        return 0;
}

int
listen_socket(const char *host, const char *port)
{
        struct addrinfo hints, *res, *res0;
        int error;
        int save_errno;
        int s;
        const char *cause = NULL;

        memset(&hints, 0, sizeof(hints));
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        hints.ai_flags = AI_PASSIVE;
        error = getaddrinfo(host, port, &hints, &res0);
        if (error)
                errx(1, "%s", gai_strerror(error));
        for (res = res0; res; res = res->ai_next) {
                s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
                if (s == -1) {
                        cause = "socket";
                        continue;
                }
                if (bind(s, res->ai_addr, res->ai_addrlen) == -1) {
                        cause = "bind";
                        save_errno = errno;
                        close(s);
                        s = -1;
                        errno = save_errno;
                        continue;
                }
                break;  /* okay we got one */
        }
        if (s == -1)
                err(1, "%s", cause);
        freeaddrinfo(res0);

        if (listen(s, 5) == -1)
                err(1, "listen");
        return s;
}

int
accept_socket(int s)
{
        struct sockaddr_storage ss;
        socklen_t slen;
        char host[NI_MAXHOST], port[NI_MAXSERV];

        slen = sizeof(ss);
        s = accept(s, (struct sockaddr *)&ss, &slen);
        if (s == -1)
                err(1, "accept");
        if (getnameinfo((struct sockaddr *)&ss, ss.ss_len, host, sizeof(host),
            port, sizeof(port), NI_NUMERICHOST | NI_NUMERICSERV))
                errx(1, "getnameinfo");
        fprintf(stderr, "peer: %s %s\n", host, port);

        return s;
}