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      1 // Copyright 2014 PDFium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
      6 // Original code is licensed as follows:
      7 /*
      8  * Copyright 2007 ZXing authors
      9  *
     10  * Licensed under the Apache License, Version 2.0 (the "License");
     11  * you may not use this file except in compliance with the License.
     12  * You may obtain a copy of the License at
     13  *
     14  *      http://www.apache.org/licenses/LICENSE-2.0
     15  *
     16  * Unless required by applicable law or agreed to in writing, software
     17  * distributed under the License is distributed on an "AS IS" BASIS,
     18  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     19  * See the License for the specific language governing permissions and
     20  * limitations under the License.
     21  */
     22 
     23 #include "xfa/src/fxbarcode/barcode.h"
     24 #include "BC_ReedSolomonGF256.h"
     25 #include "BC_ReedSolomonGF256Poly.h"
     26 CBC_ReedSolomonGF256Poly::CBC_ReedSolomonGF256Poly(CBC_ReedSolomonGF256* field,
     27                                                    int32_t coefficients) {
     28   if (field == NULL) {
     29     return;
     30   }
     31   m_field = field;
     32   m_coefficients.Add(coefficients);
     33 }
     34 CBC_ReedSolomonGF256Poly::CBC_ReedSolomonGF256Poly() {
     35   m_field = NULL;
     36 }
     37 void CBC_ReedSolomonGF256Poly::Init(CBC_ReedSolomonGF256* field,
     38                                     CFX_Int32Array* coefficients,
     39                                     int32_t& e) {
     40   if (coefficients == NULL || coefficients->GetSize() == 0) {
     41     e = BCExceptionCoefficientsSizeIsNull;
     42     BC_EXCEPTION_CHECK_ReturnVoid(e);
     43   }
     44   m_field = field;
     45   int32_t coefficientsLength = coefficients->GetSize();
     46   if ((coefficientsLength > 1 && (*coefficients)[0] == 0)) {
     47     int32_t firstNonZero = 1;
     48     while ((firstNonZero < coefficientsLength) &&
     49            ((*coefficients)[firstNonZero] == 0)) {
     50       firstNonZero++;
     51     }
     52     if (firstNonZero == coefficientsLength) {
     53       m_coefficients.Copy(*(m_field->GetZero()->GetCoefficients()));
     54     } else {
     55       m_coefficients.SetSize(coefficientsLength - firstNonZero);
     56       for (int32_t i = firstNonZero, j = 0; i < coefficientsLength; i++, j++) {
     57         m_coefficients[j] = coefficients->operator[](i);
     58       }
     59     }
     60   } else {
     61     m_coefficients.Copy(*coefficients);
     62   }
     63 }
     64 CFX_Int32Array* CBC_ReedSolomonGF256Poly::GetCoefficients() {
     65   return &m_coefficients;
     66 }
     67 int32_t CBC_ReedSolomonGF256Poly::GetDegree() {
     68   return m_coefficients.GetSize() - 1;
     69 }
     70 FX_BOOL CBC_ReedSolomonGF256Poly::IsZero() {
     71   return m_coefficients[0] == 0;
     72 }
     73 int32_t CBC_ReedSolomonGF256Poly::GetCoefficients(int32_t degree) {
     74   return m_coefficients[m_coefficients.GetSize() - 1 - degree];
     75 }
     76 int32_t CBC_ReedSolomonGF256Poly::EvaluateAt(int32_t a) {
     77   if (a == 0) {
     78     return GetCoefficients(0);
     79   }
     80   int32_t size = m_coefficients.GetSize();
     81   if (a == 1) {
     82     int32_t result = 0;
     83     for (int32_t i = 0; i < size; i++) {
     84       result = CBC_ReedSolomonGF256::AddOrSubtract(result, m_coefficients[i]);
     85     }
     86     return result;
     87   }
     88   int32_t result = m_coefficients[0];
     89   for (int32_t j = 1; j < size; j++) {
     90     result = CBC_ReedSolomonGF256::AddOrSubtract(m_field->Multiply(a, result),
     91                                                  m_coefficients[j]);
     92   }
     93   return result;
     94 }
     95 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::Clone(int32_t& e) {
     96   CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
     97   temp->Init(m_field, &m_coefficients, e);
     98   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
     99   return temp;
    100 }
    101 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::AddOrSubtract(
    102     CBC_ReedSolomonGF256Poly* other,
    103     int32_t& e) {
    104   if (IsZero()) {
    105     return other->Clone(e);
    106     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    107   }
    108   if (other->IsZero()) {
    109     return this->Clone(e);
    110     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    111   }
    112   CFX_Int32Array smallerCoefficients;
    113   smallerCoefficients.Copy(m_coefficients);
    114   CFX_Int32Array largerCoefficients;
    115   largerCoefficients.Copy(*(other->GetCoefficients()));
    116   if (smallerCoefficients.GetSize() > largerCoefficients.GetSize()) {
    117     CFX_Int32Array temp;
    118     temp.Copy(smallerCoefficients);
    119     smallerCoefficients.Copy(largerCoefficients);
    120     largerCoefficients.Copy(temp);
    121   }
    122   CFX_Int32Array sumDiff;
    123   sumDiff.SetSize(largerCoefficients.GetSize());
    124   int32_t lengthDiff =
    125       largerCoefficients.GetSize() - smallerCoefficients.GetSize();
    126   for (int32_t i = 0; i < lengthDiff; i++) {
    127     sumDiff[i] = largerCoefficients[i];
    128   }
    129   for (int32_t j = lengthDiff; j < largerCoefficients.GetSize(); j++) {
    130     sumDiff[j] = (CBC_ReedSolomonGF256::AddOrSubtract(
    131         smallerCoefficients[j - lengthDiff], largerCoefficients[j]));
    132   }
    133   CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
    134   temp->Init(m_field, &sumDiff, e);
    135   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    136   return temp;
    137 }
    138 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::Multiply(
    139     CBC_ReedSolomonGF256Poly* other,
    140     int32_t& e) {
    141   if (IsZero() || other->IsZero()) {
    142     CBC_ReedSolomonGF256Poly* temp = m_field->GetZero()->Clone(e);
    143     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    144     return temp;
    145   }
    146   CFX_Int32Array aCoefficients;
    147   aCoefficients.Copy(m_coefficients);
    148   int32_t aLength = m_coefficients.GetSize();
    149   CFX_Int32Array bCoefficients;
    150   bCoefficients.Copy(*(other->GetCoefficients()));
    151   int32_t bLength = other->GetCoefficients()->GetSize();
    152   CFX_Int32Array product;
    153   product.SetSize(aLength + bLength - 1);
    154   for (int32_t i = 0; i < aLength; i++) {
    155     int32_t aCoeff = m_coefficients[i];
    156     for (int32_t j = 0; j < bLength; j++) {
    157       product[i + j] = CBC_ReedSolomonGF256::AddOrSubtract(
    158           product[i + j],
    159           m_field->Multiply(aCoeff, other->GetCoefficients()->operator[](j)));
    160     }
    161   }
    162   CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
    163   temp->Init(m_field, &product, e);
    164   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    165   return temp;
    166 }
    167 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::Multiply(int32_t scalar,
    168                                                              int32_t& e) {
    169   if (scalar == 0) {
    170     CBC_ReedSolomonGF256Poly* temp = m_field->GetZero()->Clone(e);
    171     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    172     return temp;
    173   }
    174   if (scalar == 1) {
    175     return this->Clone(e);
    176     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    177   }
    178   int32_t size = m_coefficients.GetSize();
    179   CFX_Int32Array product;
    180   product.SetSize(size);
    181   for (int32_t i = 0; i < size; i++) {
    182     product[i] = m_field->Multiply(m_coefficients[i], scalar);
    183   }
    184   CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
    185   temp->Init(m_field, &product, e);
    186   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    187   return temp;
    188 }
    189 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::MultiplyByMonomial(
    190     int32_t degree,
    191     int32_t coefficient,
    192     int32_t& e) {
    193   if (degree < 0) {
    194     e = BCExceptionDegreeIsNegative;
    195     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    196   }
    197   if (coefficient == 0) {
    198     CBC_ReedSolomonGF256Poly* temp = m_field->GetZero()->Clone(e);
    199     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    200     return temp;
    201   }
    202   int32_t size = m_coefficients.GetSize();
    203   CFX_Int32Array product;
    204   product.SetSize(size + degree);
    205   for (int32_t i = 0; i < size; i++) {
    206     product[i] = (m_field->Multiply(m_coefficients[i], coefficient));
    207   }
    208   CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
    209   temp->Init(m_field, &product, e);
    210   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    211   return temp;
    212 }
    213 CFX_PtrArray* CBC_ReedSolomonGF256Poly::Divide(CBC_ReedSolomonGF256Poly* other,
    214                                                int32_t& e) {
    215   if (other->IsZero()) {
    216     e = BCExceptionDivideByZero;
    217     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    218   }
    219   CBC_ReedSolomonGF256Poly* rsg1 = m_field->GetZero()->Clone(e);
    220   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    221   CBC_AutoPtr<CBC_ReedSolomonGF256Poly> quotient(rsg1);
    222   CBC_ReedSolomonGF256Poly* rsg2 = this->Clone(e);
    223   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    224   CBC_AutoPtr<CBC_ReedSolomonGF256Poly> remainder(rsg2);
    225   int32_t denominatorLeadingTerm = other->GetCoefficients(other->GetDegree());
    226   int32_t inverseDenominatorLeadingTeam =
    227       m_field->Inverse(denominatorLeadingTerm, e);
    228   BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    229   while (remainder->GetDegree() >= other->GetDegree() && !remainder->IsZero()) {
    230     int32_t degreeDifference = remainder->GetDegree() - other->GetDegree();
    231     int32_t scale =
    232         m_field->Multiply(remainder->GetCoefficients((remainder->GetDegree())),
    233                           inverseDenominatorLeadingTeam);
    234     CBC_ReedSolomonGF256Poly* rsg3 =
    235         other->MultiplyByMonomial(degreeDifference, scale, e);
    236     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    237     CBC_AutoPtr<CBC_ReedSolomonGF256Poly> term(rsg3);
    238     CBC_ReedSolomonGF256Poly* rsg4 =
    239         m_field->BuildMonomial(degreeDifference, scale, e);
    240     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    241     CBC_AutoPtr<CBC_ReedSolomonGF256Poly> iteratorQuotient(rsg4);
    242     CBC_ReedSolomonGF256Poly* rsg5 =
    243         quotient->AddOrSubtract(iteratorQuotient.get(), e);
    244     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    245     CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp(rsg5);
    246     quotient = temp;
    247     CBC_ReedSolomonGF256Poly* rsg6 = remainder->AddOrSubtract(term.get(), e);
    248     BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    249     CBC_AutoPtr<CBC_ReedSolomonGF256Poly> temp1(rsg6);
    250     remainder = temp1;
    251   }
    252   CFX_PtrArray* tempPtrA = new CFX_PtrArray;
    253   tempPtrA->Add(quotient.release());
    254   tempPtrA->Add(remainder.release());
    255   return tempPtrA;
    256 }
    257 CBC_ReedSolomonGF256Poly::~CBC_ReedSolomonGF256Poly() {
    258   m_coefficients.RemoveAll();
    259 }
    260