XRootD
XrdCksCalcadler32.hh
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1 #ifndef __XRDCKSCALCADLER32_HH__
2 #define __XRDCKSCALCADLER32_HH__
3 /******************************************************************************/
4 /* */
5 /* X r d C k s C a l c a d l e r 3 2 . h h */
6 /* */
7 /* (c) 2011 by the Board of Trustees of the Leland Stanford, Jr., University */
8 /* All Rights Reserved */
9 /* Produced by Andrew Hanushevsky for Stanford University under contract */
10 /* DE-AC02-76-SFO0515 with the Department of Energy */
11 /* */
12 /* This file is part of the XRootD software suite. */
13 /* */
14 /* XRootD is free software: you can redistribute it and/or modify it under */
15 /* the terms of the GNU Lesser General Public License as published by the */
16 /* Free Software Foundation, either version 3 of the License, or (at your */
17 /* option) any later version. */
18 /* */
19 /* XRootD is distributed in the hope that it will be useful, but WITHOUT */
20 /* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or */
21 /* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public */
22 /* License for more details. */
23 /* */
24 /* You should have received a copy of the GNU Lesser General Public License */
25 /* along with XRootD in a file called COPYING.LESSER (LGPL license) and file */
26 /* COPYING (GPL license). If not, see <http://www.gnu.org/licenses/>. */
27 /* */
28 /* The copyright holder's institutional names and contributor's names may not */
29 /* be used to endorse or promote products derived from this software without */
30 /* specific prior written permission of the institution or contributor. */
31 /******************************************************************************/
32 
33 #include <sys/types.h>
34 #include <netinet/in.h>
35 #include <cinttypes>
36 
37 #include "XrdCks/XrdCksCalc.hh"
38 #include "XrdSys/XrdSysPlatform.hh"
39 
40 /* The following implementation of adler32 was derived from zlib and is
41  * Copyright (C) 1995-1998 Mark Adler
42  Below are the zlib license terms for this implementation.
43 */
44 
45 /* zlib.h -- interface of the 'zlib' general purpose compression library
46  version 1.1.4, March 11th, 2002
47 
48  Copyright (C) 1995-2002 Jean-loup Gailly and Mark Adler
49 
50  This software is provided 'as-is', without any express or implied
51  warranty. In no event will the authors be held liable for any damages
52  arising from the use of this software.
53 
54  Permission is granted to anyone to use this software for any purpose,
55  including commercial applications, and to alter it and redistribute it
56  freely, subject to the following restrictions:
57 
58  1. The origin of this software must not be misrepresented; you must not
59  claim that you wrote the original software. If you use this software
60  in a product, an acknowledgment in the product documentation would be
61  appreciated but is not required.
62  2. Altered source versions must be plainly marked as such, and must not be
63  misrepresented as being the original software.
64  3. This notice may not be removed or altered from any source distribution.
65 
66  Jean-loup Gailly Mark Adler
67  jloup@gzip.org madler@alumni.caltech.edu
68 
69 
70  The data format used by the zlib library is described by RFCs (Request for
71  Comments) 1950 to 1952 in the files ftp://ds.internic.net/rfc/rfc1950.txt
72  (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
73 */
74 
75 #define DO1(buf) {unSum1 += *buf++; unSum2 += unSum1;}
76 #define DO2(buf) DO1(buf); DO1(buf);
77 #define DO4(buf) DO2(buf); DO2(buf);
78 #define DO8(buf) DO4(buf); DO4(buf);
79 #define DO16(buf) DO8(buf); DO8(buf);
80 
82 {
83 public:
84 
85 char *Final()
86  {AdlerValue = (unSum2 << 16) | unSum1;
87 #ifndef Xrd_Big_Endian
88  AdlerValue = htonl(AdlerValue);
89 #endif
90  return (char *)&AdlerValue;
91  }
92 
93 void Init() {unSum1 = AdlerStart; unSum2 = 0;}
94 
96 
97 void Update(const char *Buff, int BLen)
98  {int k;
99  unsigned char *buff = (unsigned char *)Buff;
100  while(BLen > 0)
101  {k = (BLen < AdlerNMax ? BLen : AdlerNMax);
102  BLen -= k;
103  while(k >= 16) {DO16(buff); k -= 16;}
104  if (k != 0) do {DO1(buff);} while (--k);
105  unSum1 %= AdlerBase; unSum2 %= AdlerBase;
106  }
107  }
108 
109 const char *Type(int &csSize) {csSize = sizeof(AdlerValue); return "adler32";}
110 
112 virtual ~XrdCksCalcadler32() {}
113 
114 private:
115 
116 static const unsigned int AdlerBase = 0xFFF1;
117 static const unsigned int AdlerStart = 0x0001;
118 static const int AdlerNMax = 5552;
119 
120 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
121 
122  unsigned int AdlerValue;
123  unsigned int unSum1;
124  unsigned int unSum2;
125 };
126 #endif
#define DO16(buf)
#define DO1(buf)
void Update(const char *Buff, int BLen)
const char * Type(int &csSize)
XrdCksCalc * New()