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
|
/*
* Copyright (C) 2007-2018 S[&]T, The Netherlands.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef CODA_READ_BYTES_H
#define CODA_READ_BYTES_H
#include "coda-bin-internal.h"
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
/* be careful not to bypass this function and try to access mem_ptr directly by casting its contents to
* e.g. int16, int32, etc. This will not work since many platforms require these types of data to start
* at a word aligned boundary memory address.
* For such data types to be read from mem_ptr, you will first have to copy the value into a proper
* word aligned memory address (which is the pointer you pass as 'dst').
* Accessing data as a char array from mem_ptr can however be done safely (and can thus potentially be
* done without using this function, if there is a need for it).
*/
static int read_bytes(coda_product *product, int64_t byte_offset, int64_t length, void *dst)
{
if (product->mem_ptr != NULL)
{
if (((uint64_t)byte_offset + length) > ((uint64_t)product->mem_size))
{
if (product->format == coda_format_ascii || product->format == coda_format_binary)
{
coda_set_error(CODA_ERROR_OUT_OF_BOUNDS_READ, "trying to read beyond the end of the file");
return -1;
}
else
{
char accessed_str[21];
char offset_str[21];
char size_str[21];
coda_str64(length, accessed_str);
coda_str64(byte_offset, offset_str);
coda_str64(product->mem_size, size_str);
coda_set_error(CODA_ERROR_OUT_OF_BOUNDS_READ, "trying to read %s bytes at position %s in block of "
"size %s", accessed_str, offset_str, size_str);
return -1;
}
}
memcpy(dst, product->mem_ptr + byte_offset, (size_t)length);
}
else
{
assert(product->format == coda_format_ascii || product->format == coda_format_binary);
if (((uint64_t)byte_offset + length) > ((uint64_t)product->file_size))
{
coda_set_error(CODA_ERROR_OUT_OF_BOUNDS_READ, "trying to read beyond the end of the file");
return -1;
}
#if HAVE_PREAD
if (pread(((coda_bin_product *)product)->fd, dst, (size_t)length, (off_t)byte_offset) < 0)
{
coda_set_error(CODA_ERROR_FILE_READ, "could not read from file (%s)", strerror(errno));
return -1;
}
#else
if (lseek(((coda_bin_product *)product)->fd, (off_t)byte_offset, SEEK_SET) < 0)
{
char byte_offset_str[21];
coda_str64(byte_offset, byte_offset_str);
coda_set_error(CODA_ERROR_FILE_READ, "could not move to byte position %s (%s)", byte_offset_str,
strerror(errno));
return -1;
}
if (read(((coda_bin_product *)product)->fd, dst, (size_t)length) < 0)
{
coda_set_error(CODA_ERROR_FILE_READ, "could not read from file (%s)", strerror(errno));
return -1;
}
#endif
}
return 0;
}
#endif
|
