/*
    Loki_Update - A tool for updating Loki products over the Internet
    Copyright (C) 2000  Loki Software, Inc.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    info@lokigames.com
*/

/* I modified this file a little, removing unneeded features and making the
   thing compile ( Andreas Umbach <marvin@dataway.ch> ) */

#include <limits.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#ifndef macintosh
#ifndef WIN32
#    include <unistd.h>
#endif
#endif

#ifndef PATH_MAX
#define PATH_MAX 8192
#endif

#if !defined(WIN32) && !defined(macintosh) && !defined(__APPLE__)
void goto_installpath(const char *argv0)
{
    char temppath[PATH_MAX];
    char datapath[PATH_MAX];
    char *home;

    home = getenv("HOME");
    if ( ! home ) {
        home = ".";
    }

    strncpy(temppath, argv0, PATH_MAX); 
    if ( ! strrchr(temppath, '/') ) {
        char *path;
        char *last;
        int found;

        found = 0;
        path = getenv("PATH");
        do {
            /* Initialize our filename variable */
            temppath[0] = '\0';

            /* Get next entry from path variable */
            last = strchr(path, ':');
            if ( ! last )
                last = path+strlen(path);

            /* Perform tilde expansion */
            if ( *path == '~' ) {
                strcpy(temppath, home);
                ++path;
            }

            /* Fill in the rest of the filename */
            if ( last > (path+1) ) {
                strncat(temppath, path, (last-path));
                strcat(temppath, "/");
            }
            strcat(temppath, "./");
            strcat(temppath, argv0);

            /* See if it exists, and update path */
            if (access(temppath, X_OK) == 0) {
                ++found;
            }
            path = last+1;

        } while ( *last && !found );

    } else {
        /* Increment argv0 to the basename */
        argv0 = strrchr(argv0, '/')+1;
    }

    /* Now canonicalize it to a full pathname for the data path */
    datapath[0] = '\0';
    if ( realpath(temppath, datapath) ) {
        /* There should always be '/' in the path */
        *(strrchr(datapath, '/')) = '\0';
    }
    if ( ! *datapath || (chdir(datapath) < 0) ) {
        fprintf(stderr, "Couldn't change to install directory\n");
        exit(1); /* OK: critical, installation corrupt */
    }
}
#endif