sysdep.c

wireshark 0.99.7 最新源码

/* sysdep.c
 * UUID system dependent routines 
 *
 * $Id: sysdep.c 21694 2007-05-06 08:15:17Z gal $
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <[e-mail]>
 * Copyright 1998 Gerald Combs
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

/*
** Copyright (c) 1990- 1993, 1996 Open Software Foundation, Inc.
** Copyright (c) 1989 by Hewlett-Packard Company, Palo Alto, Ca. &
** Digital Equipment Corporation, Maynard, Mass.
** Copyright (c) 1998 Microsoft.
** To anyone who acknowledges that this file is provided "AS IS"
** without any express or implied warranty: permission to use, copy,
** modify, and distribute this file for any purpose is hereby
** granted without fee, provided that the above copyright notices and
** this notice appears in all source code copies, and that none of
** the names of Open Software Foundation, Inc., Hewlett-Packard
** Company, Microsoft, or Digital Equipment Corporation be used in
** advertising or publicity pertaining to distribution of the software
** without specific, written prior permission. Neither Open Software
** Foundation, Inc., Hewlett-Packard Company, Microsoft, nor Digital
** Equipment Corporation makes any representations about the
** suitability of this software for any purpose.
*/

#include <stdio.h>
#include "sysdep.h"

/* system dependent call to get IEEE node ID.
   This sample implementation generates a random node ID. */
void get_ieee_node_identifier(uuid_node_t *node)
{
    static inited = 0;
    static uuid_node_t saved_node;
    char seed[16];
    FILE *fp;

    if (!inited) {
        fp = fopen("nodeid", "rb");
        if (fp) {
            fread(&saved_node, sizeof saved_node, 1, fp);
            fclose(fp);
        }
        else {
            get_random_info(seed);
            seed[0] |= 0x01;
            memcpy(&saved_node, seed, sizeof saved_node);
            fp = fopen("nodeid", "wb");
            if (fp) {
                fwrite(&saved_node, sizeof saved_node, 1, fp);
                fclose(fp);
            }
        }
        inited = 1;
    }

    *node = saved_node;
}

/* system dependent call to get the current system time. Returned as
   100ns ticks since UUID epoch, but resolution may be less than
   100ns. */
#ifdef _WINDOWS_

void get_system_time(uuid_time_t *uuid_time)
{
    ULARGE_INTEGER time;

    /* NT keeps time in FILETIME format which is 100ns ticks since
       Jan 1, 1601. UUIDs use time in 100ns ticks since Oct 15, 1582.
       The difference is 17 Days in Oct + 30 (Nov) + 31 (Dec)
       + 18 years and 5 leap days. */
    GetSystemTimeAsFileTime((FILETIME *)&time);
    time.QuadPart +=

          (unsigned __int64) (1000*1000*10)       // seconds
        * (unsigned __int64) (60 * 60 * 24)       // days
        * (unsigned __int64) (17+30+31+365*18+5); // # of days
    *uuid_time = time.QuadPart;
}

/* Sample code, not for use in production; see RFC 1750 */
void get_random_info(char seed[16])
{
    MD5_CTX c;
    struct {
        MEMORYSTATUS m;
        SYSTEM_INFO s;
        FILETIME t;
        LARGE_INTEGER pc;
        DWORD tc;
        DWORD l;
        char hostname[MAX_COMPUTERNAME_LENGTH + 1];
    } r;

    MD5Init(&c);
    GlobalMemoryStatus(&r.m);
    GetSystemInfo(&r.s);
    GetSystemTimeAsFileTime(&r.t);
    QueryPerformanceCounter(&r.pc);
    r.tc = GetTickCount();
    r.l = MAX_COMPUTERNAME_LENGTH + 1;
    GetComputerNameA(r.hostname, &r.l);
    MD5Update(&c, &r, sizeof r);
    MD5Final(seed, &c);
}

#else

void get_system_time(uuid_time_t *uuid_time)
{
    struct timeval tp;

    gettimeofday(&tp, (struct timezone *)0);

    /* Offset between UUID formatted times and Unix formatted times.
       UUID UTC base time is October 15, 1582.
       Unix base time is January 1, 1970.*/
    *uuid_time = ((unsigned64)tp.tv_sec * 10000000)
        + ((unsigned64)tp.tv_usec * 10)
        + I64(0x01B21DD213814000);
}

/* Sample code, not for use in production; see RFC 1750 */
void get_random_info(char seed[16])
{
    MD5_CTX c;
    struct {
        struct sysinfo s;
        struct timeval t;
        char hostname[257];
    } r;

    MD5Init(&c);
    sysinfo(&r.s);
    gettimeofday(&r.t, (struct timezone *)0);
    gethostname(r.hostname, 256);
    MD5Update(&c, &r, sizeof r);
    MD5Final(seed, &c);
}

#endif