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SNMP上手攻略

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        if ((session =3D SnmpMgrOpen(agent, community, timeout, =
retries)) =3D=3D NULL)
        {
            printf("error on SnmpMgrOpen %d\n", GetLastError());
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            return 1;
        }
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    } // end if(TRAP)
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    // Determine and perform the requested operation.
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    if      (operation =3D=3D GET || operation =3D=3D GETNEXT)
    {
        // Get and GetNext are relatively simple operations to perform.
        // Simply initiate the request and process the result and/or
        // possible error conditions.
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        if (operation =3D=3D GET)
            requestType =3D ASN_RFC1157_GETREQUEST;
        else
            requestType =3D ASN_RFC1157_GETNEXTREQUEST;
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        // Request that the API carry out the desired operation.
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        if (!SnmpMgrRequest(session, requestType, &variableBindings,
            &errorStatus, &errorIndex))
        {
            // The API is indicating an error.
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            printf("error on SnmpMgrRequest %d\n", GetLastError());
        }
        else
        {
            // The API succeeded, errors may be indicated from the =
remote
            // agent.           =20
            switch(errorStatus)
            {
            case SNMP_ERRORSTATUS_TOOBIG:
                {
                    printf("SNMP_ERRORSTATUS_TOOBIG");
                    break;
                }
            case SNMP_ERRORSTATUS_NOSUCHNAME:
                {
                    printf("SNMP_ERRORSTATUS_NOSUCHNAME");
                    break;
                }
            case SNMP_ERRORSTATUS_BADVALUE:
                {
                    printf("SNMP_ERRORSTATUS_BADVALUE");
                    break;
                }
            default:
                break;
            }           =20
            if (errorStatus > 0)
            {
                printf("Error: errorStatus=3D%d, errorIndex=3D%d\n",
                    errorStatus, errorIndex);
            }
            else
            {
                // Display the resulting variable bindings.
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                UINT i;
                char *string =3D NULL;
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                for(i=3D0; i < variableBindings.len; i++)
                {
                    SnmpMgrOidToStr(&variableBindings.list[i].name, =
&string);
                    printf("Variable =3D %s\n", string);
                    if (string) SNMP_free(string);
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                    printf("Value    =3D ");
                    =
SnmpUtilPrintAsnAny(&variableBindings.list[i].value);
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                    printf("\n");
                } // end for()
            }
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            // Free the variable bindings that have been allocated.      =
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            SnmpUtilVarBindListFree(&variableBindings);
        }
    }
    else if (operation =3D=3D WALK)
    {
        // Walk is a common term used to indicate that all MIB variables
        // under a given OID are to be traversed and displayed.  This is
        // a more complex operation requiring tests and looping in =
addition
        // to the steps for get/getnext above.
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        AsnObjectIdentifier root;
        AsnObjectIdentifier tempOid;
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        SnmpUtilOidCpy(&root, &variableBindings.list[0].name);
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        requestType =3D ASN_RFC1157_GETNEXTREQUEST;
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        while(1)
        {
            if (!SnmpMgrRequest(session, requestType, =
&variableBindings,
                &errorStatus, &errorIndex))
            {
                // The API is indicating an error.
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                printf("error on SnmpMgrRequest %d\n", GetLastError());
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                break;
            }
            else
            {
                // The API succeeded, errors may be indicated from the =
remote
                // agent.
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                // Test for end of subtree or end of MIB.
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                if (errorStatus =3D=3D SNMP_ERRORSTATUS_NOSUCHNAME ||
                    SnmpUtilOidNCmp(&variableBindings.list[0].name,
                    &root, root.idLength))
                {
                    printf("End of MIB subtree.\n\n");
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                    break;
                }
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                // Test for general error conditions or sucesss.
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                if (errorStatus > 0)
                {
                    printf("Error: errorStatus=3D%d, errorIndex=3D%d =
\n",
                        errorStatus, errorIndex);
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                    break;
                }
                else
                {
                    // Display resulting variable binding for this =
iteration.
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                    char *string =3D NULL;
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                    SnmpMgrOidToStr(&variableBindings.list[0].name, =
&string);
                    printf("Variable =3D %s\n", string);
                    if (string) SNMP_free(string);
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                    printf("Value    =3D ");
                    =
SnmpUtilPrintAsnAny(&variableBindings.list[0].value);
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                    printf("\n");
                }
            } // end if()
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            // Prepare for the next iteration.  Make sure returned oid =
is
            // preserved and the returned value is freed.
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            SnmpUtilOidCpy(&tempOid, =
&variableBindings.list[0].name);
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            SnmpUtilVarBindFree(&variableBindings.list[0]);
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            SnmpUtilOidCpy(&variableBindings.list[0].name, =
&tempOid);
            variableBindings.list[0].value.asnType =3D ASN_NULL;
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            SnmpUtilOidFree(&tempOid);
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        } // end while()
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        // Free the variable bindings that have been allocated.
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        SnmpUtilVarBindListFree(&variableBindings);
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        SnmpUtilOidFree(&root);
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    }
    else if (operation =3D=3D TRAP)
    {
        // Trap handling can be done two different ways: event driven or
        // polled.  The following code illustrates the steps to use =
event
        // driven trap reception in a management application.
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        HANDLE hNewTraps =3D NULL;
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        if (!SnmpMgrTrapListen(&hNewTraps))
        {
            printf("error on SnmpMgrTrapListen %d\n", GetLastError());
        }
        else
        {
            printf("snmputil: listening for traps...\n");
        }
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        while(1)
        {
            DWORD dwResult;
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            if ((dwResult =3D WaitForSingleObject(hNewTraps, =
0xffffffff))
                =3D=3D 0xffffffff)
            {
                printf("error on WaitForSingleObject %d\n",
                    GetLastError());
            }
            else if (!ResetEvent(hNewTraps))
            {
                printf("error on ResetEvent %d\n", GetLastError());
            }
            else
            {
                AsnObjectIdentifier enterprise;
                AsnNetworkAddress   IPAddress;
                AsnInteger          genericTrap;
                AsnInteger          specificTrap;
                AsnTimeticks        timeStamp;
                RFC1157VarBindList  variableBindings;
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                UINT i;
                char *string =3D NULL;
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                while(SnmpMgrGetTrap(&enterprise, &IPAddress, =
&genericTrap,
                    &specificTrap, &timeStamp, =
&variableBindings))
                {
                    printf("snmputil: trap generic=3D%d =
specific=3D%d\n",
                        genericTrap, specificTrap);
                    if (IPAddress.length =3D=3D 4) {
                        printf("  from -> %d.%d.%d.%d\n",
                            (int)IPAddress.stream[0], =
(int)IPAddress.stream[1],
                            (int)IPAddress.stream[2], =
(int)IPAddress.stream[3]);
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                    }
                    if (IPAddress.dynamic) {
                        SNMP_free(IPAddress.stream);
                    }
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                    for(i=3D0; i < variableBindings.len; i++)
                    {
                        =
SnmpMgrOidToStr(&variableBindings.list[i].name, &string);
                        printf("Variable =3D %s\n", string);
                        if (string) SNMP_free(string);
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                        printf("Value    =3D ");
                        =
SnmpUtilPrintAsnAny(&variableBindings.list[i].value);
                    } // end for()
                    printf("\n");
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                    SnmpUtilOidFree(&enterprise);
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                    SnmpUtilVarBindListFree(&variableBindings);
                }
            }
        } // end while()
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    } // end if(operation)
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    if (operation !=3D TRAP)
    {
        // Close SNMP session with the remote agent.
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        if (!SnmpMgrClose(session))
        {
            printf("error on SnmpMgrClose %d\n", GetLastError());
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            return 1;
        }
    }
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    // Let the command interpreter know things went ok.
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    return 0;
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