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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
/*===========================================================================
FILE:
MemoryMappedFile.cpp
DESCRIPTION:
Implementation of cMemoryMappedFile class
PUBLIC CLASSES AND METHODS:
cMemoryMappedFile
The cMemoryMappedFile class provides the ability to read in a file
via Linux memory maps
Note: cMemoryMappedFiles are read only
Copyright (c) 2011, Code Aurora Forum. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* 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.
* Neither the name of Code Aurora Forum 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 OWNER 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.
===========================================================================*/
//-----------------------------------------------------------------------------
// Include Files
//-----------------------------------------------------------------------------
#include "StdAfx.h"
#include "MemoryMappedFile.h"
#include <sys/mman.h>
//-----------------------------------------------------------------------------
// Definitions
//-----------------------------------------------------------------------------
// Maximum size of a file this interface will try to open (64 MB)
const DWORD MAX_FILE_SZ = 1024 * 1024 * 64;
/*=========================================================================*/
// cMemoryMappedFile Methods
/*=========================================================================*/
/*===========================================================================
METHOD:
cMemoryMappedFile (Public Method)
DESCRIPTION:
Construct object/load file into memory
PARAMETERS
pFile [ I ] - File name
RETURN VALUE:
None
===========================================================================*/
cMemoryMappedFile::cMemoryMappedFile( LPCSTR pFile )
: mbResourceBased( false ),
mpBuffer( 0 ),
mFileSize( 0 ),
mStatus( ERROR_FILE_NOT_FOUND )
{
if (pFile == 0 || pFile[0] == 0)
{
return;
}
// Open the file
mFile = open( pFile, O_RDONLY );
if (mFile == -1)
{
TRACE( "Unable to Map %s to memory. Error %d: %s\n",
pFile,
errno,
strerror( errno ) );
return;
}
// Grab the file size
struct stat fileInfo;
if (fstat( mFile, &fileInfo ) != 0)
{
TRACE( "Unable to get info for %s. Error %d: %s\n",
pFile,
errno,
strerror( errno ) );
return;
}
DWORD fileSize = fileInfo.st_size;
// Map to mpBuffer
mpBuffer = mmap( 0,
fileSize,
PROT_READ,
MAP_SHARED | MAP_POPULATE,
mFile,
0 );
if (mpBuffer == 0 || mpBuffer == MAP_FAILED )
{
TRACE( "Memory map failed error %d:, %s\n",
errno,
strerror( errno ) );
return;
}
// Success!
mFileSize = fileSize;
mStatus = NO_ERROR;
}
/*===========================================================================
METHOD:
cMemoryMappedFile (Public Method)
DESCRIPTION:
Construct object/load resource based file into memory
PARAMETERS
pStart [ I ] - Start location of object
nSize [ I ] - Size of object
RETURN VALUE:
None
===========================================================================*/
cMemoryMappedFile::cMemoryMappedFile(
const char * pStart,
const int nSize )
: mbResourceBased( true ),
mpBuffer( 0 ),
mFileSize( 0 ),
mStatus( INVALID_HANDLE_VALUE )
{
// Set size
mFileSize = nSize;
// Set memory pointer
mpBuffer = (void * )pStart;
// Success!
mStatus = NO_ERROR;
}
/*===========================================================================
METHOD:
~cMemoryMappedFile (Public Method)
DESCRIPTION:
Destructor
RETURN VALUE:
None
===========================================================================*/
cMemoryMappedFile::~cMemoryMappedFile()
{
if (mbResourceBased == false)
{
if (munmap( mpBuffer, mFileSize ) == -1)
{
TRACE( "Memory unmapping error %d: %s\n",
errno,
strerror( errno ) );
return;
}
}
}
|
