inet.c

snmp的源代码,已经在我的ubuntu下编译通过

    if (strcmp(name, "udp") == 0) {
        request = snmp_pdu_create(SNMP_MSG_GETNEXT);
        snmp_add_null_var(request, oid_udptable,
                          sizeof(oid_udptable) / sizeof(oid));
        status = STAT_SUCCESS;
    } else
        status = STAT_TIMEOUT;
    while (status == STAT_SUCCESS) {
        if (response)
            snmp_free_pdu(response);
        response = NULL;
        status = snmp_synch_response(Session, request, &response);
        if (status != STAT_SUCCESS
            || response->errstat != SNMP_ERR_NOERROR) {
            fprintf(stderr, "SNMP request failed\n");
            break;
        }
        vp = response->variables;
        if (!vp)
            break;
        if (vp->name_length != 15 ||
            memcmp(vp->name, oid_udptable, sizeof(oid_udptable))) {
            break;
        }

        request = snmp_pdu_create(SNMP_MSG_GETNEXT);
        snmp_add_null_var(request, vp->name, vp->name_length);

        instance = vp->name + 10;
        for (up = udpconn; up != NULL; up = up->next) {
            if (!memcmp(instance, up->instance, sizeof(up->instance)))
                break;
        }
        if (up == NULL) {
            up = (struct udp_entry *) calloc(1, sizeof(struct udp_entry));
            if (up == NULL)
                break;
            if (udplast != NULL)
                udplast->next = up;
            udplast = up;
            if (udpconn == NULL)
                udpconn = up;
            memmove(up->instance, instance, sizeof(up->instance));
        }

        if (vp->name[UDP_ENTRY] == UDP_LOCADDR) {
            memmove(&up->localAddress, vp->val.string, sizeof(u_long));
            up->locAddrSet = 1;
        }

        if (vp->name[UDP_ENTRY] == UDP_LOCPORT) {
            if (validUShortAssign(&up->localPort, *vp->val.integer,
                                  "UDP_LOCPORT"))
                up->locPortSet = 1;
        }
    }
    if (response)
        snmp_free_pdu(response);
    response = NULL;

    for (first = 1, up = udpconn, newup = NULL; up != NULL; up = up->next) {
        if (newup)
            free(newup);
        newup = up;
        if (!(up->locAddrSet && up->locPortSet)) {
            printf("incomplete entry\n");
            continue;
        }
        if (first) {
            printf("Active Internet (%s) Connections", name);
            putchar('\n');
            printf("%-5.5s %-28.28s\n", "Proto", "Local Address");
            first = 0;
        }
        printf("%-5.5s ", "udp");
        inetprint(&up->localAddress, up->localPort, "udp");
        putchar('\n');
    }
    if (newup)
        free(newup);

}

int
validUShortAssign(unsigned short *pushort, int ival, const char *errstr)
{
    u_long          ulval = (u_long) ival;
    if (ival > 65535) {
        printf("Warning: %s value %ld (0x%lx) is not a port address\n",
               errstr, ulval, ulval);
        return 0;
    }
    *pushort = (unsigned short) ulval;
    return 1;
}


/*
 * Dump UDP statistics structure.
 */
void
udp_stats(void)
{
    oid             varname[MAX_OID_LEN], *udpentry;
    size_t          varname_len;
    netsnmp_variable_list *var;
    int             count;
    struct stat_table *sp = udp_stattab;

    memmove(varname, oid_udpstats, sizeof(oid_udpstats));
    varname_len = sizeof(oid_udpstats) / sizeof(oid);
    udpentry = varname + 7;
    printf("udp:\n");
    count = sizeof(udp_stattab) / sizeof(struct stat_table);
    while (count--) {
        *udpentry = sp->entry;
        var = getvarbyname(Session, varname, varname_len);
        if (var && var->val.integer) {
            putchar('\t');
            printf(sp->description, *var->val.integer,
                   plural((int) *var->val.integer));
            putchar('\n');
        }
        if (var)
            snmp_free_var(var);
        sp++;
    }

}

/*
 * Dump TCP statistics structure.
 */
void
tcp_stats(void)
{
    oid             varname[MAX_OID_LEN], *tcpentry;
    size_t          varname_len;
    netsnmp_variable_list *var;
    int             count;
    struct stat_table *sp = tcp_stattab;

    memmove(varname, oid_tcpstats, sizeof(oid_tcpstats));
    varname_len = sizeof(oid_tcpstats) / sizeof(oid);
    tcpentry = varname + 7;
    printf("tcp:\n");
    count = sizeof(tcp_stattab) / sizeof(struct stat_table);
    while (count--) {
        *tcpentry = sp->entry;
        var = getvarbyname(Session, varname, varname_len);
        if (var && var->val.integer) {
            putchar('\t');
            printf(sp->description, *var->val.integer,
                   plural((int) *var->val.integer));
            putchar('\n');
        }
        if (var)
            snmp_free_var(var);
        sp++;
    }

}

/*
 * Dump IP statistics structure.
 */
void
ip_stats(void)
{
    oid             varname[MAX_OID_LEN], *ipentry;
    size_t          varname_len;
    netsnmp_variable_list *var;
    int             count;
    struct stat_table *sp = ip_stattab;

    memmove(varname, oid_ipstats, sizeof(oid_ipstats));
    varname_len = sizeof(oid_ipstats) / sizeof(oid);
    ipentry = varname + 7;
    printf("ip:\n");
    count = sizeof(ip_stattab) / sizeof(struct stat_table);
    while (count--) {
        *ipentry = sp->entry;
        var = getvarbyname(Session, varname, varname_len);
        if (var && var->val.integer) {
            putchar('\t');
            printf(sp->description, *var->val.integer,
                   plural((int) *var->val.integer));
            putchar('\n');
        }
        if (var)
            snmp_free_var(var);
        sp++;
    }

}

/*
 * Dump ICMP statistics.
 */
void
icmp_stats(void)
{
    oid             varname[MAX_OID_LEN], *icmpentry;
    size_t          varname_len;
    netsnmp_variable_list *var;
    int             count, first;
    struct stat_table *sp;

    memmove(varname, oid_icmpstats, sizeof(oid_icmpstats));
    varname_len = sizeof(oid_icmpstats) / sizeof(oid);
    icmpentry = varname + 7;
    printf("icmp:\n");
    sp = icmp_stattab;
    count = sizeof(icmp_stattab) / sizeof(struct stat_table);
    while (count--) {
        *icmpentry = sp->entry;
        var = getvarbyname(Session, varname, varname_len);
        if (var && var->val.integer) {
            putchar('\t');
            printf(sp->description, *var->val.integer,
                   plural((int) *var->val.integer));
            putchar('\n');
        }
        if (var)
            snmp_free_var(var);
        sp++;
    }

    sp = icmp_outhistogram;
    first = 1;
    count = sizeof(icmp_outhistogram) / sizeof(struct stat_table);
    while (count--) {
        *icmpentry = sp->entry;
        var = getvarbyname(Session, varname, varname_len);
        if (var && var->val.integer && *var->val.integer != 0) {
            if (first) {
                printf("\tOutput Histogram:\n");
                first = 0;
            }
            printf("\t\t");
            printf(sp->description, *var->val.integer,
                   plural((int) *var->val.integer));
            putchar('\n');
        }
        if (var)
            snmp_free_var(var);
        sp++;
    }

    sp = icmp_inhistogram;
    first = 1;
    count = sizeof(icmp_inhistogram) / sizeof(struct stat_table);
    while (count--) {
        *icmpentry = sp->entry;
        var = getvarbyname(Session, varname, varname_len);
        if (var && var->val.integer && *var->val.integer != 0) {
            if (first) {
                printf("\tInput Histogram:\n");
                first = 0;
            }
            printf("\t\t");
            printf(sp->description, *var->val.integer,
                   plural((int) *var->val.integer));
            putchar('\n');
        }
        if (var)
            snmp_free_var(var);
        sp++;
    }
}

/*
 * Pretty print an Internet address (net address + port).
 * If the nflag was specified, use numbers instead of names.
 */
void
inetprint(struct in_addr *in, u_short port, const char *proto)
{
    struct servent *sp = 0;
    char            line[80], *cp;
    int             width;

    sprintf(line, "%.*s.", 18, inetname(*in));
    cp = (char *) strchr(line, '\0');
    if (!nflag && port)
        sp = getservbyport(htons(port), proto);
    if (sp || port == 0)
        sprintf(cp, "%.12s", sp ? sp->s_name : "*");
    else
        sprintf(cp, "%d", port);
    width = 28;
    printf(" %-*.*s", width, width, line);
}

/*
 * Construct an Internet address representation.
 * If the nflag has been supplied, give 
 * numeric value, otherwise try for symbolic name.
 */
static char    *
inetname(struct in_addr in)
{
    register char  *cp;
    static char     line[50];
    struct hostent *hp;
    struct netent  *np;
    static char     domain[MAXHOSTNAMELEN + 1];
    static int      first = 1;

    if (first && !nflag) {
        first = 0;
        if (gethostname(domain, MAXHOSTNAMELEN) == 0 &&
            (cp = (char *) strchr(domain, '.')))
            (void) strcpy(domain, cp + 1);
        else
            domain[0] = 0;
    }
    cp = 0;
    if (!nflag && in.s_addr != INADDR_ANY) {
        u_long          net = inet_netof(in);
        u_long          lna = inet_lnaof(in);

        if (lna == INADDR_ANY) {
            np = getnetbyaddr(net, AF_INET);
            if (np)
                cp = np->n_name;
        }
        if (cp == 0) {
            hp = gethostbyaddr((char *) &in, sizeof(in), AF_INET);
            if (hp) {
                if ((cp = (char *) strchr(hp->h_name, '.')) &&
                    !strcmp(cp + 1, domain))
                    *cp = 0;
                cp = (char *) hp->h_name;
            }
        }
    }
    if (in.s_addr == INADDR_ANY)
        strcpy(line, "*");
    else if (cp) {
        strncpy(line, cp, sizeof(line));
        line[ sizeof(line)-1 ] = 0;
    } else {
        in.s_addr = ntohl(in.s_addr);
#define C(x)	(unsigned)((x) & 0xff)
        sprintf(line, "%u.%u.%u.%u", C(in.s_addr >> 24),
                C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
    }
    return (line);
}