CFX_PtrArray* CBC_ReedSolomonGF256Poly::Divide(CBC_ReedSolomonGF256Poly* other,
int32_t& e) {
if (other->IsZero()) {
e = BCExceptionDivideByZero;
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
}
CBC_ReedSolomonGF256Poly* rsg1 = m_field->GetZero()->Clone(e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
CBC_AutoPtr<CBC_ReedSolomonGF256Poly> quotient(rsg1);
CBC_ReedSolomonGF256Poly* rsg2 = this->Clone(e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
CBC_AutoPtr<CBC_ReedSolomonGF256Poly> remainder(rsg2);
int32_t denominatorLeadingTerm = other->GetCoefficients(other->GetDegree());
int32_t inverseDenominatorLeadingTeam =
m_field->Inverse(denominatorLeadingTerm, e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
while (remainder->GetDegree() >= other->GetDegree() && !remainder->IsZero()) {
int32_t degreeDifference = remainder->GetDegree() - other->GetDegree();
int32_t scale =
m_field->Multiply(remainder->GetCoefficients((remainder->GetDegree())),
inverseDenominatorLeadingTeam);
CBC_ReedSolomonGF256Poly* rsg3 =
other->MultiplyByMonomial(degreeDifference, scale, e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
CBC_AutoPtr<CBC_ReedSolomonGF256Poly> term(rsg3);
CBC_ReedSolomonGF256Poly* rsg4 =
m_field->BuildMonomial(degreeDifference, scale, e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
CBC_AutoPtr<CBC_ReedSolomonGF256Poly> iteratorQuotient(rsg4);
CBC_ReedSolomonGF256Poly* rsg5 =
quotient->AddOrSubtract(iteratorQuotient.get(), e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp(rsg5);
quotient = temp;
CBC_ReedSolomonGF256Poly* rsg6 = remainder->AddOrSubtract(term.get(), e);
BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp1(rsg6);
remainder = temp1;
}
CFX_PtrArray* tempPtrA = new CFX_PtrArray;
tempPtrA->Add(quotient.release());
tempPtrA->Add(remainder.release());
return tempPtrA;
}
CFX_ArrayTemplate<CBC_ReedSolomonGF256Poly*>* CBC_ReedSolomonGF256Poly::Divide(
CBC_ReedSolomonGF256Poly* other,
int32_t& e) {
if (other->IsZero()) {
e = BCExceptionDivideByZero;
return nullptr;
}
std::unique_ptr<CBC_ReedSolomonGF256Poly> quotient(
m_field->GetZero()->Clone(e));
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
std::unique_ptr<CBC_ReedSolomonGF256Poly> remainder(Clone(e));
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
int32_t denominatorLeadingTerm = other->GetCoefficients(other->GetDegree());
int32_t inverseDenominatorLeadingTeam =
m_field->Inverse(denominatorLeadingTerm, e);
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
while (remainder->GetDegree() >= other->GetDegree() && !remainder->IsZero()) {
int32_t degreeDifference = remainder->GetDegree() - other->GetDegree();
int32_t scale =
m_field->Multiply(remainder->GetCoefficients((remainder->GetDegree())),
inverseDenominatorLeadingTeam);
std::unique_ptr<CBC_ReedSolomonGF256Poly> term(
other->MultiplyByMonomial(degreeDifference, scale, e));
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
std::unique_ptr<CBC_ReedSolomonGF256Poly> iteratorQuotient(
m_field->BuildMonomial(degreeDifference, scale, e));
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
quotient.reset(quotient->AddOrSubtract(iteratorQuotient.get(), e));
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
remainder.reset(remainder->AddOrSubtract(term.get(), e));
BC_EXCEPTION_CHECK_ReturnValue(e, nullptr);
}
CFX_ArrayTemplate<CBC_ReedSolomonGF256Poly*>* tempPtrA =
new CFX_ArrayTemplate<CBC_ReedSolomonGF256Poly*>();
tempPtrA->Add(quotient.release());
tempPtrA->Add(remainder.release());
return tempPtrA;
}
