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/fxbarcode/common/reedsolomon/BC_ReedSolomonGF256Poly.h"
24
25 #include <memory>
26
27 #include "xfa/fxbarcode/common/reedsolomon/BC_ReedSolomonGF256.h"
28
CBC_ReedSolomonGF256Poly(CBC_ReedSolomonGF256 * field,int32_t coefficients)29 CBC_ReedSolomonGF256Poly::CBC_ReedSolomonGF256Poly(CBC_ReedSolomonGF256* field,
30 int32_t coefficients) {
31 if (!field)
32 return;
33
34 m_field = field;
35 m_coefficients.Add(coefficients);
36 }
CBC_ReedSolomonGF256Poly()37 CBC_ReedSolomonGF256Poly::CBC_ReedSolomonGF256Poly() {
38 m_field = nullptr;
39 }
Init(CBC_ReedSolomonGF256 * field,CFX_ArrayTemplate<int32_t> * coefficients,int32_t & e)40 void CBC_ReedSolomonGF256Poly::Init(CBC_ReedSolomonGF256* field,
41 CFX_ArrayTemplate<int32_t>* coefficients,
42 int32_t& e) {
43 if (!coefficients || coefficients->GetSize() == 0) {
44 e = BCExceptionCoefficientsSizeIsNull;
45 return;
46 }
47 m_field = field;
48 int32_t coefficientsLength = coefficients->GetSize();
49 if ((coefficientsLength > 1 && (*coefficients)[0] == 0)) {
50 int32_t firstNonZero = 1;
51 while ((firstNonZero < coefficientsLength) &&
52 ((*coefficients)[firstNonZero] == 0)) {
53 firstNonZero++;
54 }
55 if (firstNonZero == coefficientsLength) {
56 m_coefficients.Copy(*(m_field->GetZero()->GetCoefficients()));
57 } else {
58 m_coefficients.SetSize(coefficientsLength - firstNonZero);
59 for (int32_t i = firstNonZero, j = 0; i < coefficientsLength; i++, j++) {
60 m_coefficients[j] = coefficients->operator[](i);
61 }
62 }
63 } else {
64 m_coefficients.Copy(*coefficients);
65 }
66 }
GetCoefficients()67 CFX_ArrayTemplate<int32_t>* CBC_ReedSolomonGF256Poly::GetCoefficients() {
68 return &m_coefficients;
69 }
GetDegree()70 int32_t CBC_ReedSolomonGF256Poly::GetDegree() {
71 return m_coefficients.GetSize() - 1;
72 }
IsZero()73 bool CBC_ReedSolomonGF256Poly::IsZero() {
74 return m_coefficients[0] == 0;
75 }
GetCoefficients(int32_t degree)76 int32_t CBC_ReedSolomonGF256Poly::GetCoefficients(int32_t degree) {
77 return m_coefficients[m_coefficients.GetSize() - 1 - degree];
78 }
EvaluateAt(int32_t a)79 int32_t CBC_ReedSolomonGF256Poly::EvaluateAt(int32_t a) {
80 if (a == 0) {
81 return GetCoefficients(0);
82 }
83 int32_t size = m_coefficients.GetSize();
84 if (a == 1) {
85 int32_t result = 0;
86 for (int32_t i = 0; i < size; i++) {
87 result = CBC_ReedSolomonGF256::AddOrSubtract(result, m_coefficients[i]);
88 }
89 return result;
90 }
91 int32_t result = m_coefficients[0];
92 for (int32_t j = 1; j < size; j++) {
93 result = CBC_ReedSolomonGF256::AddOrSubtract(m_field->Multiply(a, result),
94 m_coefficients[j]);
95 }
96 return result;
97 }
Clone(int32_t & e)98 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::Clone(int32_t& e) {
99 CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
100 temp->Init(m_field, &m_coefficients, e);
101 if (e != BCExceptionNO)
102 return nullptr;
103 return temp;
104 }
AddOrSubtract(CBC_ReedSolomonGF256Poly * other,int32_t & e)105 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::AddOrSubtract(
106 CBC_ReedSolomonGF256Poly* other,
107 int32_t& e) {
108 if (IsZero())
109 return other->Clone(e);
110 if (other->IsZero())
111 return Clone(e);
112
113 CFX_ArrayTemplate<int32_t> smallerCoefficients;
114 smallerCoefficients.Copy(m_coefficients);
115 CFX_ArrayTemplate<int32_t> largerCoefficients;
116 largerCoefficients.Copy(*(other->GetCoefficients()));
117 if (smallerCoefficients.GetSize() > largerCoefficients.GetSize()) {
118 CFX_ArrayTemplate<int32_t> temp;
119 temp.Copy(smallerCoefficients);
120 smallerCoefficients.Copy(largerCoefficients);
121 largerCoefficients.Copy(temp);
122 }
123 CFX_ArrayTemplate<int32_t> sumDiff;
124 sumDiff.SetSize(largerCoefficients.GetSize());
125 int32_t lengthDiff =
126 largerCoefficients.GetSize() - smallerCoefficients.GetSize();
127 for (int32_t i = 0; i < lengthDiff; i++) {
128 sumDiff[i] = largerCoefficients[i];
129 }
130 for (int32_t j = lengthDiff; j < largerCoefficients.GetSize(); j++) {
131 sumDiff[j] = (CBC_ReedSolomonGF256::AddOrSubtract(
132 smallerCoefficients[j - lengthDiff], largerCoefficients[j]));
133 }
134 CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
135 temp->Init(m_field, &sumDiff, e);
136 if (e != BCExceptionNO)
137 return nullptr;
138 return temp;
139 }
Multiply(CBC_ReedSolomonGF256Poly * other,int32_t & e)140 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::Multiply(
141 CBC_ReedSolomonGF256Poly* other,
142 int32_t& e) {
143 if (IsZero() || other->IsZero())
144 return m_field->GetZero()->Clone(e);
145
146 CFX_ArrayTemplate<int32_t> aCoefficients;
147 aCoefficients.Copy(m_coefficients);
148 int32_t aLength = m_coefficients.GetSize();
149 CFX_ArrayTemplate<int32_t> bCoefficients;
150 bCoefficients.Copy(*(other->GetCoefficients()));
151 int32_t bLength = other->GetCoefficients()->GetSize();
152 CFX_ArrayTemplate<int32_t> 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 if (e != BCExceptionNO)
165 return nullptr;
166 return temp;
167 }
Multiply(int32_t scalar,int32_t & e)168 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::Multiply(int32_t scalar,
169 int32_t& e) {
170 if (scalar == 0)
171 return m_field->GetZero()->Clone(e);
172 if (scalar == 1)
173 return Clone(e);
174
175 int32_t size = m_coefficients.GetSize();
176 CFX_ArrayTemplate<int32_t> product;
177 product.SetSize(size);
178 for (int32_t i = 0; i < size; i++) {
179 product[i] = m_field->Multiply(m_coefficients[i], scalar);
180 }
181 CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
182 temp->Init(m_field, &product, e);
183 if (e != BCExceptionNO)
184 return nullptr;
185 return temp;
186 }
MultiplyByMonomial(int32_t degree,int32_t coefficient,int32_t & e)187 CBC_ReedSolomonGF256Poly* CBC_ReedSolomonGF256Poly::MultiplyByMonomial(
188 int32_t degree,
189 int32_t coefficient,
190 int32_t& e) {
191 if (degree < 0) {
192 e = BCExceptionDegreeIsNegative;
193 return nullptr;
194 }
195 if (coefficient == 0)
196 return m_field->GetZero()->Clone(e);
197
198 int32_t size = m_coefficients.GetSize();
199 CFX_ArrayTemplate<int32_t> product;
200 product.SetSize(size + degree);
201 for (int32_t i = 0; i < size; i++) {
202 product[i] = (m_field->Multiply(m_coefficients[i], coefficient));
203 }
204 CBC_ReedSolomonGF256Poly* temp = new CBC_ReedSolomonGF256Poly();
205 temp->Init(m_field, &product, e);
206 if (e != BCExceptionNO)
207 return nullptr;
208 return temp;
209 }
210
Divide(CBC_ReedSolomonGF256Poly * other,int32_t & e)211 CFX_ArrayTemplate<CBC_ReedSolomonGF256Poly*>* CBC_ReedSolomonGF256Poly::Divide(
212 CBC_ReedSolomonGF256Poly* other,
213 int32_t& e) {
214 if (other->IsZero()) {
215 e = BCExceptionDivideByZero;
216 return nullptr;
217 }
218 std::unique_ptr<CBC_ReedSolomonGF256Poly> quotient(
219 m_field->GetZero()->Clone(e));
220 if (e != BCExceptionNO)
221 return nullptr;
222 std::unique_ptr<CBC_ReedSolomonGF256Poly> remainder(Clone(e));
223 if (e != BCExceptionNO)
224 return nullptr;
225 int32_t denominatorLeadingTerm = other->GetCoefficients(other->GetDegree());
226 int32_t inverseDenominatorLeadingTeam =
227 m_field->Inverse(denominatorLeadingTerm, e);
228 if (e != BCExceptionNO)
229 return nullptr;
230 while (remainder->GetDegree() >= other->GetDegree() && !remainder->IsZero()) {
231 int32_t degreeDifference = remainder->GetDegree() - other->GetDegree();
232 int32_t scale =
233 m_field->Multiply(remainder->GetCoefficients((remainder->GetDegree())),
234 inverseDenominatorLeadingTeam);
235 std::unique_ptr<CBC_ReedSolomonGF256Poly> term(
236 other->MultiplyByMonomial(degreeDifference, scale, e));
237 if (e != BCExceptionNO)
238 return nullptr;
239 std::unique_ptr<CBC_ReedSolomonGF256Poly> iteratorQuotient(
240 m_field->BuildMonomial(degreeDifference, scale, e));
241 if (e != BCExceptionNO)
242 return nullptr;
243 quotient.reset(quotient->AddOrSubtract(iteratorQuotient.get(), e));
244 if (e != BCExceptionNO)
245 return nullptr;
246 remainder.reset(remainder->AddOrSubtract(term.get(), e));
247 if (e != BCExceptionNO)
248 return nullptr;
249 }
250 CFX_ArrayTemplate<CBC_ReedSolomonGF256Poly*>* tempPtrA =
251 new CFX_ArrayTemplate<CBC_ReedSolomonGF256Poly*>();
252 tempPtrA->Add(quotient.release());
253 tempPtrA->Add(remainder.release());
254 return tempPtrA;
255 }
256
~CBC_ReedSolomonGF256Poly()257 CBC_ReedSolomonGF256Poly::~CBC_ReedSolomonGF256Poly() {
258 m_coefficients.RemoveAll();
259 }
260