ReactOS  0.4.13-dev-922-g2fbff73
crc32.c
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1 /*
2  * File crc32.c - calculate CRC32 checksum of a file
3  *
4  * Copyright (C) 1996, Eric Youngdale.
5  * 1999-2007 Eric Pouech
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
20  */
21 
22 #include "config.h"
23 #include "wine/port.h"
24 
25 #include <stdio.h>
26 
27 #include "dbghelp_private.h"
28 
29 /* Copyright (C) 1986 Gary S. Brown
30  * Modified by Robert Shearman. You may use the following calc_crc32 code or
31  * tables extracted from it, as desired without restriction. */
32 
33 /**********************************************************************\
34 |* Demonstration program to compute the 32-bit CRC used as the frame *|
35 |* check sequence in ADCCP (ANSI X3.66, also known as FIPS PUB 71 *|
36 |* and FED-STD-1003, the U.S. versions of CCITT's X.25 link-level *|
37 |* protocol). The 32-bit FCS was added via the Federal Register, *|
38 |* 1 June 1982, p.23798. I presume but don't know for certain that *|
39 |* this polynomial is or will be included in CCITT V.41, which *|
40 |* defines the 16-bit CRC (often called CRC-CCITT) polynomial. FIPS *|
41 |* PUB 78 says that the 32-bit FCS reduces otherwise undetected *|
42 |* errors by a factor of 10^-5 over 16-bit FCS. *|
43 \**********************************************************************/
44 
45 /* First, the polynomial itself and its table of feedback terms. The */
46 /* polynomial is */
47 /* X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0 */
48 /* Note that we take it "backwards" and put the highest-order term in */
49 /* the lowest-order bit. The X^32 term is "implied"; the LSB is the */
50 /* X^31 term, etc. The X^0 term (usually shown as "+1") results in */
51 /* the MSB being 1. */
52 
53 /* Note that the usual hardware shift register implementation, which */
54 /* is what we're using (we're merely optimizing it by doing eight-bit */
55 /* chunks at a time) shifts bits into the lowest-order term. In our */
56 /* implementation, that means shifting towards the right. Why do we */
57 /* do it this way? Because the calculated CRC must be transmitted in */
58 /* order from highest-order term to lowest-order term. UARTs transmit */
59 /* characters in order from LSB to MSB. By storing the CRC this way, */
60 /* we hand it to the UART in the order low-byte to high-byte; the UART */
61 /* sends each low-bit to high-bit; and the result is transmission bit */
62 /* by bit from highest- to lowest-order term without requiring any bit */
63 /* shuffling on our part. Reception works similarly. */
64 
65 /* The feedback terms table consists of 256, 32-bit entries. Notes: */
66 /* */
67 /* 1. The table can be generated at runtime if desired; code to do so */
68 /* is shown later. It might not be obvious, but the feedback */
69 /* terms simply represent the results of eight shift/xor opera- */
70 /* tions for all combinations of data and CRC register values. */
71 /* */
72 /* 2. The CRC accumulation logic is the same for all CRC polynomials, */
73 /* be they sixteen or thirty-two bits wide. You simply choose the */
74 /* appropriate table. Alternatively, because the table can be */
75 /* generated at runtime, you can start by generating the table for */
76 /* the polynomial in question and use exactly the same "updcrc", */
77 /* if your application needn't simultaneously handle two CRC */
78 /* polynomials. (Note, however, that XMODEM is strange.) */
79 /* */
80 /* 3. For 16-bit CRCs, the table entries need be only 16 bits wide; */
81 /* of course, 32-bit entries work OK if the high 16 bits are zero. */
82 /* */
83 /* 4. The values must be right-shifted by eight bits by the "updcrc" */
84 /* logic; the shift must be unsigned (bring in zeroes). On some */
85 /* hardware you could probably optimize the shift in assembler by */
86 /* using byte-swap instructions. */
87 
88 
90 {
91 #define UPDC32(octet,crc) (crc_32_tab[((crc) ^ (octet)) & 0xff] ^ ((crc) >> 8))
92  static const DWORD crc_32_tab[] =
93  { /* CRC polynomial 0xedb88320 */
94  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
95  0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
96  0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
97  0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
98  0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
99  0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
100  0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
101  0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
102  0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
103  0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
104  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
105  0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
106  0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
107  0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
108  0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
109  0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
110  0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
111  0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
112  0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
113  0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
114  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
115  0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
116  0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
117  0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
118  0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
119  0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
120  0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
121  0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
122  0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
123  0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
124  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
125  0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
126  0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
127  0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
128  0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
129  0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
130  0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
131  0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
132  0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
133  0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
134  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
135  0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
136  0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
137  };
138  int i, r;
139  unsigned char buffer[8192];
140  DWORD crc = ~0;
141 
142  lseek(fd, 0, SEEK_SET);
143  while ((r = read(fd, buffer, sizeof(buffer))) > 0)
144  {
145  for (i = 0; i < r; i++) crc = UPDC32(buffer[i], crc);
146  }
147  return ~crc;
148 #undef UPDC32
149 }
GLdouble GLdouble GLdouble r
Definition: gl.h:2055
GLuint buffer
Definition: glext.h:5915
static int fd
Definition: io.c:51
_Check_return_opt_ _CRTIMP long __cdecl lseek(_In_ int _FileHandle, _In_ long _Offset, _In_ int _Origin)
DWORD calc_crc32(int fd)
Definition: crc32.c:89
#define UPDC32(octet, crc)
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
#define SEEK_SET
Definition: jmemansi.c:26
unsigned long DWORD
Definition: ntddk_ex.h:95
static const unsigned int crc_32_tab[]
Definition: mspatcha.c:272
_CRTIMP int __cdecl read(_In_ int _FileHandle, _Out_writes_bytes_(_MaxCharCount) void *_DstBuf, _In_ unsigned int _MaxCharCount)