Example Code for Using LDAP VLV

The following example code shows how to create and use a VLV control in LDAP.

#define SECURITY_WIN32
#include <windows.h>
#include <stdio.h>
#include <winldap.h>
#include <rpc.h>
#include <rpcdce.h>
#include <security.h>

void __cdecl main (int argc, char* argv[])
{
   LDAP *ld;
   ULONG ldaperr;

   ld = ldap_open("servername", 389);

   if (ld) 
   {
	printf("Open succeeded\n");
   } 
   else 
   {
	printf("Open failed\n");
	return;
   }

   ldaperr = ldap_bind_s(ld, NULL, NULL, LDAP_AUTH_NEGOTIATE);

   if (ldaperr == LDAP_SUCCESS) 
   {

	printf("Bind succeeded\n");
   } 
   else 
   {
	printf("Bind failed with 0x%x  0x%x\n", ldaperr, GetLastError);
	ldap_unbind(ld);
return;
   }

   //Create the VLV control and send it to the server.

   LDAPVLVInfo	 vlvInfo;
   PLDAPControl	pvlvctrl;
   PLDAPControl	psortctrl;
   PLDAPControl	ctrlArr[3];

   //Fill in the members of the VLV control.

   vlvInfo.ldvlv_after_count = 1;
   vlvInfo.ldvlv_attrvalue = NULL;
   vlvInfo.ldvlv_before_count = 1;
   vlvInfo.ldvlv_context = NULL;
   vlvInfo.ldvlv_count = 0;
   vlvInfo.ldvlv_extradata = NULL;
   vlvInfo.ldvlv_offset = 2;
   vlvInfo.ldvlv_version = LDAP_VLVINFO_VERSION;

   ldaperr = ldap_create_vlv_control( ld,
									&vlvInfo,
									TRUE,
									&pvlvctrl);

   printf("Create VLV control returned 0x%x\n",ldaperr);
if (LDAP_SUCCESS != ldaperr)
return;

   //Create a sort control and tack it on.

   LDAPSortKey sortkeys;
   PLDAPSortKey sortkeyList[2];

   sortkeys.sk_attrtype = "name";
   sortkeys.sk_matchruleoid = NULL;
   sortkeys.sk_reverseorder = FALSE;

   sortkeyList[0] = &sortkeys;
   sortkeyList[1] = NULL;

   ldaperr = ldap_create_sort_control( ld,
									 sortkeyList,
									 TRUE,
									 &psortctrl
									 );

   printf("Create Sort control returned 0x%x\n",ldaperr);
if (LDAP_SUCCESS != ldaperr)
return;
   
   ctrlArr[0] = psortctrl;
   ctrlArr[1] = pvlvctrl;
   ctrlArr[2] = NULL;

   //Send the Vlv control with a search request to the server.

   PLDAPMessage pRes;

   ldaperr = ldap_search_ext_s( ld,
								"OU=Users,DC=DCname,
								 DC=Fabrikam,DC=com",
								LDAP_SCOPE_SUBTREE,
								(objectClass=*),
								NULL,
								1,
								ctrlArr,
								NULL,
								NULL,
								0,
								&pRes
								);

   printf("Ldap search returned 0x%x\n",ldaperr);
   
   //Pick the control sent back from the server.

   PLDAPControl	*pvlvresponse = NULL;

   ldaperr = ldap_parse_result( ld,
								pRes,
								NULL,
								NULL,
								NULL,
								NULL,
								&pvlvresponse,
								FALSE
								);

   printf("Ldap parse_result returned 0x%x\n",ldaperr);

   //Parse the vlv control sent back from the server.

   ULONG   targetpos =0;
   ULONG   listcount = 0;
   int	 errcode = LDAP_SUCCESS;
   PBERVAL context = NULL;

   ldaperr = ldap_parse_vlv_control( ld,
									 pvlvresponse,
									 &targetpos,
									 &listcount,
									 &context,
									 &errcode
									 );

   printf("Ldap parse vlv control returned 0x%x\n",ldaperr);
   printf("TargetPos = %d\n", targetpos);
   printf("ListCount = %d\n", listcount);
   printf("errcode = 0x%x\n", errcode);

   ldap_unbind(ld);
}