1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
/*
* Copyright © 1999-2001 NCSA
* All rights reserved.
*
* Programmer: Raymond Lu<slu@ncsa.uiuc.edu>
* Jan 3, 2003
*/
#include "H5private.h"
#include "H5Eprivate.h"
#include "H5MMprivate.h"
#include "H5Zprivate.h"
#ifdef H5_HAVE_FILTER_ADLER32
#define ADLER_LEN 4
#define ADLER_BASE 65521
/* Interface initialization */
#define PABLO_MASK H5Z_adler32_mask
#define INTERFACE_INIT NULL
static int interface_initialize_g = 0;
/*-------------------------------------------------------------------------
* Function: H5Z_filter_adler32_compute
*
* Purpose: Implement an Adler32 Checksum
*
* Return: Success: Adler32 value
*
* Failure: Can't fail
*
* Programmer: Raymond Lu
* Jan 3, 2003
*
* Modifications:
*
*-------------------------------------------------------------------------
*/
static unsigned int H5Z_filter_adler32_compute(unsigned char *buf, size_t len)
{
size_t i;
register unsigned int s1 = 1;
register unsigned int s2 = 0;
FUNC_ENTER_NOINIT(H5Z_filter_adler32_compute);
/* Compute checksum */
for(i=0; i<len; i++) {
s1 = (s1 + *buf++) % ADLER_BASE;
s2 = (s2 + s1) % ADLER_BASE;
}
FUNC_LEAVE_NOAPI((s2 << 16) + s1);
}
/*-------------------------------------------------------------------------
* Function: H5Z_filter_adler32
*
* Purpose: Implement an I/O filter of Adler32 Checksum
*
* Return: Success: size of data plus the size of Adler32 value
*
* Failure: 0
*
* Programmer: Raymond Lu
* Jan 3, 2003
*
* Modifications:
*
*-------------------------------------------------------------------------
*/
size_t
H5Z_filter_adler32 (unsigned flags, size_t cd_nelmts, const unsigned cd_values[],
size_t nbytes, size_t *buf_size, void **buf)
{
size_t ret_value = 0;
void *outbuf = NULL;
unsigned char *src = (unsigned char*)(*buf);
unsigned int adler = 1;
FUNC_ENTER_NOAPI(H5Z_filter_adler32, 0);
assert(sizeof(unsigned int)==4);
if (flags & H5Z_FLAG_REVERSE) { /* Read */
size_t src_nbytes = nbytes;
unsigned int origin_adler;
/* Do checksum if it's enabled for read; otherwise skip it
* to save performance. */
if (!(flags & H5Z_FLAG_SKIP_EDC)) { /* Read */
unsigned char *tmp_src;
src_nbytes -= ADLER_LEN;
tmp_src=src+src_nbytes;
UINT32DECODE(tmp_src, origin_adler);
/* Compute checksum */
adler = H5Z_filter_adler32_compute(src,src_nbytes);
if(origin_adler != adler)
HGOTO_ERROR(H5E_STORAGE, H5E_READERROR, 0, "data error detected by Adler32 checksum");
}
*buf_size = nbytes - ADLER_LEN;
ret_value = *buf_size;
} else { /* Write */
unsigned char *dst;
/* Compute checksum */
adler = H5Z_filter_adler32_compute(src,nbytes);
if (NULL==(dst=outbuf=H5MM_malloc(nbytes+ADLER_LEN)))
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "unable to allocate Adler32 checksum destination buffer");
/* Copy raw data */
HDmemcpy((void*)dst, (void*)(*buf), nbytes);
/* Append checksum to raw data */
dst += nbytes;
UINT32ENCODE(dst, adler);
*buf_size = nbytes + ADLER_LEN;
H5MM_xfree(*buf);
*buf = outbuf;
outbuf = NULL;
ret_value = *buf_size;
}
done:
if(outbuf)
H5MM_xfree(outbuf);
FUNC_LEAVE_NOAPI(ret_value);
}
#endif /* H5_HAVE_FILTER_ADLER32 */
|
