libxcks  0.1.0.1
crc32.cpp
Go to the documentation of this file.
1 /*
2  * libxcks
3  * Copyright (C) 2022 Julien Couot
4  *
5  * This program is free software: you can redistribute it and/or modify it
6  * under the terms of the GNU Lesser General Public License as published by
7  * the Free Software Foundation, either version 3 of the License, or (at your
8  * option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
13  * License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public License
16  * along with this program. If not, see <https://www.gnu.org/licenses/>.
17  */
18 
24 //---------------------------------------------------------------------------
25 #include <sstream>
26 
27 #include "crc32.hpp"
28 //---------------------------------------------------------------------------
29 
31 using namespace std;
32 
33 
34 namespace libxcks
35 {
36 // Table used to compute the CRC32 value.
37 const uint32_t CRC32::crc_table[256] =
38 {
39  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419,
40  0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4,
41  0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07,
42  0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
43  0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856,
44  0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
45  0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4,
46  0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
47  0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3,
48  0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a,
49  0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599,
50  0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
51  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190,
52  0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f,
53  0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e,
54  0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
55  0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed,
56  0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
57  0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3,
58  0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
59  0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a,
60  0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5,
61  0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010,
62  0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
63  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17,
64  0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6,
65  0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615,
66  0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
67  0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344,
68  0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
69  0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a,
70  0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
71  0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1,
72  0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c,
73  0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef,
74  0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
75  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe,
76  0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31,
77  0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c,
78  0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
79  0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b,
80  0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
81  0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1,
82  0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
83  0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278,
84  0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7,
85  0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66,
86  0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
87  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605,
88  0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8,
89  0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b,
90  0x2d02ef8d
91 };
92 //---------------------------------------------------------------------------
93 
94 
95 /*
96  * Default constructor.
97  */
98 CRC32::CRC32()
99 {
100  reset();
101 }
102 //---------------------------------------------------------------------------
103 
104 
105 /*
106  * Resets the CRC32 to initial value.
107  */
108 void CRC32::reset()
109 {
110  crc32 = 0xffffffff;
111 }
112 //---------------------------------------------------------------------------
113 
114 
115 /*
116  * Returns the CRC32 value.
117  */
118 uint32_t CRC32::getUint32Value() const
119 {
120  return crc32 ^ 0xffffffff;
121 }
122 //---------------------------------------------------------------------------
123 
124 
125 /*
126  * Returns the CRC32 value in the first 4 bytes of the given address.
127  */
128 uint8_t* CRC32::getValue(uint8_t* buffer) const
129 {
130  *(reinterpret_cast<uint32_t*>(buffer)) = swapOnLE(getUint32Value());
131  return buffer;
132 }
133 //---------------------------------------------------------------------------
134 
135 
136 /*
137  * Returns the checksum value in a string.
138  *
139  * @param hexInUpperCase If <CODE>true</CODE> the hexadecimal letters will
140  * be in uppercase.
141  * @return The current checksum value.
142  */
143 std::string CRC32::toString(const bool hexInUpperCase) const
144 {
145  ostringstream ss;
146  ss.fill('0');
147  ss.width(8);
148 
149  if (hexInUpperCase)
150  ss << uppercase << hex << getUint32Value();
151  else
152  ss << hex << getUint32Value();
153 
154  return ss.str();
155 }
156 //---------------------------------------------------------------------------
157 
158 
159 /*
160  * Updates the CRC32 with specified array of bytes.
161  */
162 void CRC32::update(const uint8_t* buf, size_t len)
163 {
164  if (buf == nullptr || len == 0)
165  return;
166 
167  do
168  {
169  crc32 = crc_table[(crc32 ^ (*buf++)) & 0xff] ^ (crc32 >> 8);
170  }
171  while (--len);
172 }
173 //---------------------------------------------------------------------------
174 
175 
181 ArrayString CRC32::getAlternativeNames()
182 {
183  return ArrayString{ "CRC-32" };
184 }
185 //---------------------------------------------------------------------------
186 } // namespace libxcks
187 //---------------------------------------------------------------------------
crc32.hpp
Compute crc32.
libxcks::ArrayString
std::vector< std::string > ArrayString
Array of strings.
Definition: types.hpp:44