src/server.c

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2016 Mike Becker. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include "network.h"
#include "game.h"
#include "chess/game-info.h"
#include "chess/pgn.h"
#include <ncurses.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>

static int server_fd = -1;
static void interrupt_listen(int sig) {
    if (server_fd > -1) {
        // this interrupts
        close(server_fd);
    }
}

static int server_open(Server *server, Settings *settings) {
    printw("\nListening for client...\n");
    refresh();
    if (settings->usedomainsocket
            ? net_create_sock(server, settings->serverhost)
            : net_create_tcp(server, settings->port)) {
        addstr("Server creation failed");
        return 1;
    }

    // allow Ctrl+C to interrupt the listening process
    server_fd = server->fd;
    signal(SIGINT, interrupt_listen);

    if (net_listen(server)) {
        addstr("Listening for client failed or interrupted");
        return 1;
    }

    // restore default action
    signal(SIGINT, SIG_DFL);
    
    return 0;
}

static int server_handshake(Client *client) {
    net_send_code(client->fd, NETCODE_VERSION);
    if (net_recieve_code(client->fd) != NETCODE_VERSION) {
        addstr("Client uses an incompatible software version.");
        return 1;
    }

    addstr("Client connected - transmitting gameinfo...");
    refresh();
    
    return 0;
}

int server_run(Settings *settings) {
    Server server;
    
    dump_gameinfo(&(settings->gameinfo));
    GameState gamestate;
    gamestate_init(&gamestate);
    if (settings->continuepgn) {
        /* preload PGN data before handshake */
        FILE *pgnfile = fopen(settings->continuepgn, "r");
        if (pgnfile) {
            int result = read_pgn(pgnfile, &gamestate,
                &(settings->gameinfo));
            long position = ftell(pgnfile);
            fclose(pgnfile);
            if (result) {
                printw("Invalid PGN file content at position %ld:\n%s\n",
                        position, pgn_error_str(result));
                return 1;
            }
            if (!is_game_running(&gamestate)) {
                addstr("Game has ended. Use -S to analyze it.\n");
                return 1;
            }
            addch('\n');
            dump_moveinfo(&gamestate);
            addch('\n');
        } else {
            printw("Can't read PGN file (%s)\n", strerror(errno));
            return 1;
        }
    }
    
    if (server_open(&server, settings)) {
        net_destroy(&server);
        return 1;
    }
    
    if (server_handshake(server.client)) {
        net_destroy(&server);
        return 1;
    }

    int fd = server.client->fd;
    if (settings->continuepgn) {
        /* Continue game, send PGN data */
        uint16_t mc = 0;
        MoveList *movelist = gamestate.movelist;
        while (movelist) {
            mc++;
            movelist = movelist->next;
        }
        
        Move* moves = calloc(mc, sizeof(Move));
        
        movelist = gamestate.movelist;
        mc = 0;
        while (movelist) {
            moves[mc] = movelist->move;
            mc++;
            movelist = movelist->next;
        }
        
        size_t pgndata_size = sizeof(GameInfo)+sizeof(mc)+mc*sizeof(Move);
        char *pgndata = malloc(pgndata_size);
        memcpy(pgndata, &(settings->gameinfo), sizeof(GameInfo));
        memcpy(pgndata+sizeof(GameInfo), &mc, sizeof(mc));
        memcpy(pgndata+sizeof(GameInfo)+sizeof(mc), moves, mc*sizeof(Move));
        free(moves);
        net_send_data(fd, NETCODE_PGNDATA, pgndata, pgndata_size);
        free(pgndata);
    } else {
        /* Start new game */
        net_send_data(fd, NETCODE_GAMEINFO,
            &(settings->gameinfo), sizeof(GameInfo));
    }
    addstr("\rClient connected - awaiting challenge acceptance...");
    refresh();
    int code = net_recieve_code(fd);
    if (code == NETCODE_ACCEPT) {
        addstr("\rClient connected - challenge accepted.");
        clrtoeol();
        game_play(settings, &gamestate, fd);
        net_destroy(&server);
        game_review(settings, &gamestate);
        return 0;
    } else if (code == NETCODE_DECLINE) {
        addstr("\rClient connected - challenge declined.");
        clrtoeol();
        net_destroy(&server);
        return 0;
    } else if (code == NETCODE_CONNLOST) {
        addstr("\rClient connected - but gave no response.");
        clrtoeol();
        net_destroy(&server);
        return 0;
    } else {
        addstr("\rInvalid client response");
        clrtoeol();
        
        net_destroy(&server);
        return 1;
    }
}