custom aggregate function in C++

I'm using Oracle 9i.
While writing aggregate function which is supposed to find the smallest distance between points in 3d space I faced a problem which can be considered serious as far as an Oracle newbie like me is concerned. My function executes but it crashes just after the ODCIAggregateInitialize function. I repeatedly get the same error, which is

 ORA-00600: internal error code, arguments: [17099], [], [], [], [], [], [], [] ORA-28576: RPC agent connection lost

I know that ODCIAggregateIterate never happens to run. This is my PL/SQL type definition:

TYPE MINDISTANCEIMPL as object (

counter number,

static function ODCIAggregateInitialize(sctx IN OUT MinDistanceImpl)

return number as language C

library distance name "ODCIAggregateInitialize"

with context

parameters (

context,

sctx,

sctx INDICATOR STRUCT,

RETURN INDICATOR ),

member function ODCIAggregateIterate(

self IN OUT MinDistanceImpl,

value IN Coordinates)

return number as language C

library distance name "ODCIAggregateIterate"

with context

parameters (

context,

self,

self INDICATOR STRUCT,

value,

value INDICATOR STRUCT,

RETURN INDICATOR ),

member function ODCIAggregateTerminate(

self IN MinDistanceImpl, returnValue OUT number,

flags IN number) return number as language C

library distance name "ODCIAggregateTerminate"

with context

parameters (

context,

self,

self INDICATOR STRUCT,

returnValue ,

returnValue INDICATOR,

flags,

flags INDICATOR ,

RETURN INDICATOR), member function ODCIAggregateMerge(

self IN OUT MinDistanceImpl,

ctx2 IN MinDistanceImpl)

return number

);

Here is my C++ implementation (written in DLL)

// distancedll.cpp : Defines the entry point for the DLL application.

//

#include "stdafx.h"

#include <odci.h>

#include <oci.h>

#include <stdio.h>

#include <ociextp.h>

#include <math.h>

#include <fstream>

struct MinDistanceImpl

{

OCINumber* COUNTER;

};

struct MinDistanceImpl_ind

{

OCIInd _atomic;

OCIInd COUNTER;

};

struct DoubleCoordinates{

double x;

double y;

double z;

};

struct Coordinates

{

OCINumber X;

OCINumber Y;

OCINumber Z;

Coordinates(OCINumber xx, OCINumber yy, OCINumber zz): X(xx), Y(yy), Z(zz) {}

};

struct Coordinates_ind

{

OCIInd _atomic;

OCIInd X;

OCIInd Y;

OCIInd Z;

};

extern "C"

{

double dist(DoubleCoordinates c1, DoubleCoordinates c2);

double sq(double x);

DoubleCoordinates convert(Coordinates c,OCIError *errh);

static vector<Coordinates> vect;

BOOL APIENTRY DllMain( HANDLE hModule,

DWORD ul_reason_for_call,

LPVOID lpReserved)

{

return TRUE;

}

__declspec(dllexport) int ODCIAggregateInitialize(

OCIExtProcContext *context,

MinDistanceImpl * sctx,

MinDistanceImpl_ind * sctx_ind)

{

ofstream out("c:\\orainit.txt", ios_base::app);

out << "just initialized\n";

vect.clear();

out<< "cleared vector\n";

out.close();

return ODCI_SUCCESS;

}

/*

(

context,

self,

self INDICATOR STRUCT,

value,

value INDICATOR STRUCT,

RETURN INDICATOR ),

*/

__declspec(dllexport) int ODCIAggregateIterate(

OCIExtProcContext *context,

MinDistanceImpl * self,

MinDistanceImpl_ind * self_ind,

Coordinates value,

Coordinates_ind value_ind)

{

ofstream out("c:\\oraiterate.txt", ios_base::app);

out << "\n\n=================\nJust initialized\n";

vect.push_back(value);

out<<"pushed value\n";

out.close();

return ODCI_SUCCESS;

}

__declspec(dllexport) int ODCIAggregateTerminate(

OCIExtProcContext *context,

MinDistanceImpl * self,

MinDistanceImpl_ind * self_ind,

OCINumber * returnValue,

short returnValue_ind,

OCINumber * flags,

short flags_ind)

{

OCIError *errh;

OCIEnv * envh;

OCISvcCtx * svcc;

sword err;

sword status;

ofstream out("c:\\oraterminate.txt", ios_base::app);

out << "just initialized\n";

err = OCIExtProcGetEnv(context, &envh, &svcc, &errh);

out << "set up context\n";

//if(!vect.size())

// return ODCI_ERROR;

double d=0.0;

double minValue = -1.0;

int marker = 0;

for(unsigned int i=0;i<vect.size();i++)

{

out << "new big loop:" << i<<"\n";

for(unsigned int j=i;j<vect.size();j++)

{

out << "in small loop: "<<j<<"\n";

d = dist(convert(vect[i],errh), convert(vect[j],errh));

out << "just computed distance\n";

if(minValue==-1.0 || d<minValue)

{

out << "new minValue chosen\n";

minValue = d;

}

}

}

out << "after loops\n";

if(returnValue==NULL)

{

out << "return value is null\n";

returnValue = (OCINumber*) OCIExtProcAllocCallMemory(context, sizeof(OCINumber));

}

out << "before conversion of returnValue\n";

status = OCINumberFromReal(errh, &minValue, sizeof(minValue), returnValue);

out << "after conversion of returnValue\n";

out.close();

return ODCI_SUCCESS;

}

DoubleCoordinates convert(Coordinates c,OCIError *errh)

{

sword status;

double x = 0.0;

double y = 0.0;

double z = 0.0;

status = OCINumberToInt ( errh,&c.X,sizeof(double),OCI_NUMBER_SIGNED, &x );

status = OCINumberToInt ( errh,&c.Y,sizeof(double),OCI_NUMBER_SIGNED, &y );

status = OCINumberToInt ( errh,&c.Z,sizeof(double),OCI_NUMBER_SIGNED, &z );

DoubleCoordinates * dc = (DoubleCoordinates *)malloc(sizeof(DoubleCoordinates));

dc->x = x;

dc->y = y;

dc->z = z;

return *(dc);

}

double dist(DoubleCoordinates c1, DoubleCoordinates c2)

{

return sqrt((c1.x-c2.x)+sq(c1.y-c2.y)+sq(c1.z-c2.z));

}

double sq(double x)

{

return x*x;

}

} // of extern "c"

I've added these file output lines for debugging, It does not work without them either.

And at last I include the database table declaration together with code creating the aggregate function and a try to run it:

function MinDistance(val in Coordinates)

return number

aggregate using MinDistanceImpl;

create or replace type Coordinates as object (

x number,

y number,

z number

);

SELECT MinDistance(point) FROM POINTS3D;

The Points3D table is nonemty.

Can anyone help me find the bug, because I'm totally lost :(

Marcin Moczyróg Received on Fri Nov 11 2005 - 14:30:27 CST