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/*++
Copyright (c) 1992-1997 Microsoft Corporation
Module Name:
oid.c
Abstract:
Contains routines to manipulatee object identifiers.
SnmpUtilOidCpy SnmpUtilOidAppend SnmpUtilOidNCmp SnmpUtilOidCmp SnmpUtilOidFree
Environment:
User Mode - Win32
Revision History:
--*/
///////////////////////////////////////////////////////////////////////////////
// //
// Include files //
// //
///////////////////////////////////////////////////////////////////////////////
#include <snmp.h>
#include <snmputil.h>
#include <limits.h>
///////////////////////////////////////////////////////////////////////////////
// //
// Public Procedures //
// //
///////////////////////////////////////////////////////////////////////////////
SNMPAPISNMP_FUNC_TYPE SnmpUtilOidCpy( AsnObjectIdentifier * pOidDst, AsnObjectIdentifier * pOidSrc )
/*++
Routine Description:
Copy an object identifier.
Arguments:
pOidDst - pointer to structure to receive OID.
pOidSrc - pointer to OID to copy.
Return Values:
Returns SNMPAPI_NOERROR if successful.
--*/
{ SNMPAPI nResult = SNMPAPI_ERROR;
// validate pointers
if (pOidDst != NULL) {
// initialize
pOidDst->ids = NULL; pOidDst->idLength = 0;
// check for subids
if ((pOidSrc != NULL) && (pOidSrc->ids != NULL) && (pOidSrc->idLength != 0)) {
// check for arithmetic overflow
if (pOidSrc->idLength > UINT_MAX/sizeof(UINT)) {
SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: pOidSrc->idLength 0x%x will overflow.\n", pOidSrc->idLength ));
SetLastError(SNMP_MEM_ALLOC_ERROR); return nResult; }
// attempt to allocate the subids
pOidDst->ids = (UINT *)SnmpUtilMemAlloc( pOidSrc->idLength * sizeof(UINT) );
// validate pointer
if (pOidDst->ids != NULL) {
// transfer the oid length
pOidDst->idLength = pOidSrc->idLength; // transfer subids
memcpy(pOidDst->ids, pOidSrc->ids, pOidSrc->idLength * sizeof(UINT) );
nResult = SNMPAPI_NOERROR; // success...
} else {
SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: could not allocate oid.\n" ));
SetLastError(SNMP_MEM_ALLOC_ERROR); }
} else { SNMPDBG(( SNMP_LOG_WARNING, "SNMP: API: copying a null oid.\n" )); nResult = SNMPAPI_NOERROR; // success...
}
} else { SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: null oid pointer during copy.\n" ));
SetLastError(ERROR_INVALID_PARAMETER); }
return nResult;}
SNMPAPISNMP_FUNC_TYPE SnmpUtilOidAppend( AsnObjectIdentifier * pOidDst, AsnObjectIdentifier * pOidSrc )
/*++
Routine Description:
Append source OID to destination OID
Arguments:
pOidDst - pointer to structure to receive combined OID.
pOidSrc - pointer to OID to append.
Return Values:
Returns SNMPAPI_NOERROR if successful.
--*/
{ SNMPAPI nResult = SNMPAPI_ERROR;
// validate pointers
if (pOidDst != NULL) {
// check if there are subids
if ((pOidSrc != NULL) && (pOidSrc->ids != NULL) && (pOidSrc->idLength != 0)) {
// calculate the total number of subidentifiers
UINT nIds;
// check for arithmetic overflow
if (pOidDst->idLength > (UINT_MAX - pOidSrc->idLength)) {
SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: combined oid too large. Dst oid len 0x%x, Src oid len 0x%x.\n", pOidDst->idLength, pOidSrc->idLength ));
SetLastError(SNMP_BERAPI_OVERFLOW); return nResult; }
nIds = pOidDst->idLength + pOidSrc->idLength; // validate number of subids
if (nIds <= SNMP_MAX_OID_LEN) {
// attempt to allocate the subidentifiers
UINT * pIds = (UINT *)SnmpUtilMemReAlloc( pOidDst->ids, nIds * sizeof(UINT) );
// validate pointer
if (pIds != NULL) {
// transfer pointer
pOidDst->ids = pIds;
// transfer subids
memcpy(&pOidDst->ids[pOidDst->idLength], pOidSrc->ids, pOidSrc->idLength * sizeof(UINT) );
// transfer oid length
pOidDst->idLength = nIds;
nResult = SNMPAPI_NOERROR; // success...
} else {
SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: could not allocate oid.\n" ));
SetLastError(SNMP_MEM_ALLOC_ERROR); }
} else {
SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: combined oid too large.\n" ));
SetLastError(SNMP_BERAPI_OVERFLOW); }
} else { SNMPDBG(( SNMP_LOG_WARNING, "SNMP: API: appending a null oid.\n" )); nResult = SNMPAPI_NOERROR; // success...
}
} else { SNMPDBG(( SNMP_LOG_ERROR, "SNMP: API: null oid pointer during copy.\n" ));
SetLastError(ERROR_INVALID_PARAMETER); }
return nResult;}
SNMPAPISNMP_FUNC_TYPE SnmpUtilOidNCmp( AsnObjectIdentifier * pOid1, AsnObjectIdentifier * pOid2, UINT nSubIds )
/*++
Routine Description:
Compares two OIDs up to a certain subidentifier.
Arguments:
pOid1 - pointer to first OID.
pOid2 - pointer to second OID.
nSubIds - maximum subidentifiers to compare.
Return Values:
< 0 first parameter is 'less than' second. 0 first parameter is 'equal to' second. > 0 first parameter is 'greater than' second.
--*/
{ UINT i = 0;// INT nResult = 0;
// validate pointers
if ((pOid1 != NULL) && (pOid2 != NULL)) {
// calculate maximum number of subidentifiers to compare
UINT nMaxIds = min(nSubIds, min(pOid1->idLength, pOid2->idLength));
while(i < nMaxIds) { if (pOid1->ids[i] != pOid2->ids[i]) break; i++; }
// comparision length less than either OID lengths; components equals
if (i == nSubIds) return 0;
// difference encountered before either OID endings and before the
// requested comparision length
if (i < nMaxIds) return (pOid1->ids[i] < pOid2->ids[i])? -1 : 1;
// one OID is shorter than the requested comparision length
return pOid1->idLength - pOid2->idLength; }
return 0;}
SNMPAPISNMP_FUNC_TYPE SnmpUtilOidCmp( AsnObjectIdentifier * pOid1, AsnObjectIdentifier * pOid2 )
/*++
Routine Description:
Compares two OIDs.
Arguments:
pOid1 - pointer to first OID.
pOid2 - pointer to second OID.
Return Values:
< 0 first parameter is 'less than' second. 0 first parameter is 'equal to' second. > 0 first parameter is 'greater than' second.
--*/
{ // forward request to the function above
return SnmpUtilOidNCmp(pOid1,pOid2,max(pOid1->idLength,pOid2->idLength));}
VOIDSNMP_FUNC_TYPE SnmpUtilOidFree( AsnObjectIdentifier * pOid )
/*++
Routine Description:
Releases memory associated with OID.
Arguments:
pOid - pointer to OID to free.
Return Values:
None.
--*/
{ // validate
if (pOid != NULL) {
// release subids memory
SnmpUtilMemFree(pOid->ids);
// re-initialize
pOid->idLength = 0; pOid->ids = NULL; }}
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