dhcp-server.c

来自「this is sample about DHCP-agent」· C语言 代码 · 共 237 行

/* $Header: /cvsroot/dhcp-agent/dhcp-agent/src/dhcp-server.c,v 1.8 2003/07/15 10:57:18 actmodern Exp $
 *
 * Copyright 2002 Thamer Alharbash
 *
 * 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.
 * 3. The names of the authors may not be used to endorse or promote
 * products derived from this software without specific prior
 * written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 * 
 */

#define MODULE_NAME "dhcp-server"

#include "dhcp-local.h"
#include "dhcp-libutil.h"
#include "dhcp-librawnet.h"

#include "dhcp-lease.h"
#include "dhcp-server-conf.h"
#include "dhcp-server.h"
#include "dhcp-server-guile.h"

/* global vars affecting other code. */
char *work_dir = DHCPLOCALSTATE_SERVERDIR; /* our default working directory */

#if !defined(HAVE_PROGNAME)
const char *__progname;
#endif                          /* HAVE_PROGNAME */

static unsigned char want_background = 1; /* whether we should go into the background. */

static void do_version(char *interface);
static void do_status(char *interface_name);
static void do_kill(char *interface_name);
static void do_server(char *interface_name);
static void do_check_config(char *interface_name);

static const char *command_string[] = {
    "version", "kill", "status", "do server", "checkconfig"
};

/* table of functions indexed by command codes. */
server_command commands[] = {
    do_version,                 /* print out version information. */
    do_kill,                    /* kill server. */
    do_status,                  /* do status. */
    do_server,                  /* do server. */
    do_check_config,            /* check configuration. */
};

server_state server_states[] = {
    NULL,
    server_shutdown,
};

/* print usage info. */
static void usage(char *s)
{
    INFO_MESSAGE("usage: %s [-caks] [-l verbosity level]\n", s);
    exit(0);
}

/* print out version information and exit. */
static void do_version(char *interface)
{
    INFO_MESSAGE("%s version: %s\n", getprogname(), VERSION);
}

static void do_status(char *interface_name)
{
    INFO_MESSAGE("not implemented yet.");
    return;
}

static void do_kill(char *interface_name)
{
    INFO_MESSAGE("not implemented yet.");
    return;
}

static void do_server(char *interface)
{
    dhcp_server_control_t *dhcp_server_control;

    INFO_MESSAGE("DHCP server starting");

    /* we go into the background immediately. */
    if(want_background) {

        INFO_MESSAGE("going into the background");
        set_interactive(0);
        go_background(work_dir);

    }

    dhcp_server_control = dhcp_server_control_create(interface);

    if(file_create_pid(interface)) {
        ERROR_MESSAGE("could not create PID file for interface: %s", interface);
        server_states[STATE_SHUTDOWN](dhcp_server_control);
    }

    server_states[STATE_SHUTDOWN](dhcp_server_control);
}

static void do_check_config(char *interface)
{
    server_conf_t *server_conf;
    lease_definition_t *lease_def;

    server_conf = server_conf_create(interface);
    if(server_conf == NULL) {
        FATAL_MESSAGE("error while reading server conf.");
    }

    /* dump out configuration information. */

    INFO_MESSAGE("Server configuration:");
    INFO_MESSAGE(" ");

    INFO_MESSAGE("default-rebind-percent: %d", server_conf->default_rebind_percent);
    INFO_MESSAGE("default-renew-percent: %d",  server_conf->default_renew_percent);
    INFO_MESSAGE(" ");

    INFO_MESSAGE("Lease definitions:");
    INFO_MESSAGE(" ");

    list_rewind(server_conf->lease_defs);
    while((lease_def = list_next(server_conf->lease_defs)) != NULL) {
        pretty_print_lease_def(lease_def);
    }
}

/* main function: called from scm_boot_guile */
static void real_main(void *closure, int argc, char *argv[])
{
    int c, command_code = DO_SERVER;
    char *interface_name = NULL;
    list_t *interface_list;

    INFO_MESSAGE("(C) 2003 Thamer Al-Harbash <[e-mail]>");
    INFO_MESSAGE("See LICENSE file for details.");
    INFO_MESSAGE(" ");

    while((c = getopt(argc, argv, "cvskai:l:")) != -1) {

        switch(c) {

        case 'k': /* kill server. */
            command_code = DO_KILL;
            break;

        case 's':
            command_code = DO_STATUS;
            break;

        case 'c':
            command_code = DO_CHECK_CONFIG;
            break;

        case 'v':
            command_code = DO_VERSION;
            break;

        case 'i':
            interface_name = xstrdup(optarg);
            break;

        case 'a': /* don't fork into the background. */
            want_background = 0;
            break;

        case 'l':

            if(!is_signed_numeric(optarg) || set_verbosity_level(atoi(optarg))) {
                ERROR_MESSAGE("illegal verbosity level: %s", optarg);
                exit(1);
            }

            break;

        default:
            usage(argv[0]);
        }
    }

    /* if all the user wants is version information, give it to him. */
    if(command_code == DO_VERSION) {
        do_version(NULL);
        exit(0);
    }

    /* otherwise anything else requires an up interface. */

    if(interface_name == NULL) {

        interface_list = rawnet_list_active_interfaces();
        if(list_get_len(interface_list) == 0) {
            ERROR_MESSAGE("could not find suitable interface to use while running command: %s", 
                          command_string[command_code]);
        }

        interface_name = xstrdup(list_first(interface_list));
        list_destroy(interface_list, xfree);
    }

    do_change_work_dir(work_dir);

    /* now that we have an active interface name, go ahead
     * and run the server command. */
    commands[command_code](interface_name);

    exit(0);
}

/* actual main: boot guile up so it knows where the bottom of the stack is. */
int main(int argc, char *argv[])
{
    scm_boot_guile(argc, argv, real_main, NULL);

    /* get rid of compiler warning. */
    exit(1);
}