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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
|
<!doctype html public "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<HTML>
<HEAD>
<TITLE>nevrax.org : docs</TITLE>
<LINK REL=stylesheet TYPE="text/css" HREF="/inc/css/nevrax.css">
<link href="doxygen.css" rel="stylesheet" type="text/css">
</HEAD>
<BODY MARGINHEIGHT="0" MARGINWIDTH="0">
<!-- uplinks -->
<TABLE CELLSPACING=0 CELLPADDING=0 BORDER=0>
<TR>
<TD WIDTH=16><IMG SRC="/inc/img/pixel.gif" WIDTH="16" HEIGHT="16" BORDER=0 ALT=""></TD>
<TD WIDTH=140 BGCOLOR=#dddddd><IMG SRC="/inc/img/pixel.gif" WIDTH="140" HEIGHT="16" BORDER=0 ALT=""></TD>
<TD WIDTH=16><IMG SRC="/inc/img/pixel.gif" WIDTH="16" HEIGHT="16" BORDER=0 ALT=""></TD>
<TD><IMG width=6 height=14 SRC="/inc/img/reddots.gif" ALT="#" VSPACE=2 HSPACE=2 BORDER=0 ></TD><TD VALIGN=middle> <A CLASS=uplinks HREF='/'><b>Home</B></FONT></A> </TD>
<TD><IMG width=6 height=14 SRC="/inc/img/reddots.gif" ALT="#" VSPACE=2 HSPACE=2 BORDER=0 ></TD><TD VALIGN=middle> <A CLASS=uplinks HREF='/'><b>nevrax.com</B></FONT></A> </TD>
</TR>
</TABLE>
<!-- banner Nevrax -->
<TABLE CELLSPACING=0 CELLPADDING=0 BORDER=0 WIDTH=100%>
<TR><TD BGCOLOR="#000000" BACKGROUND="/inc/img/black_banner.jpg"><A HREF=""><IMG SRC="/inc/img/nevrax.gif" WIDTH="170" HEIGHT="45" BORDER=0 ALT="Nevrax" ></A></TD></TR>
</TABLE>
<!-- main table -->
<TABLE CELLSPACING=0 CELLPADDING=0 BORDER=0 height=100%>
<TR>
<TD WIDTH=16><IMG SRC="/inc/img/pixel.gif" WIDTH="16" HEIGHT="10" BORDER=0 ALT=""></TD>
<TD WIDTH=140 BGCOLOR=#dddddd VALIGN=TOP ALIGN=middle><IMG SRC="/inc/img/pixel.gif" WIDTH="140" HEIGHT="10" BORDER=0 ALT="">
<!------ Begin Box ------>
<TABLE BORDER=0 CELLSPACING=0 CELLPADDING=0 BGCOLOR=black><TR><TD><TABLE border=0 cellspacing=2 cellpadding=0 width=120><tr><TD ALIGN=middle bgcolor=black>
<FONT COLOR=white FACE="sans-serif"><B>Nevrax.org</B></FONT></TD></TR><tr><td colspan=2 bgcolor=#FFFFFF>
<TABLE cellspacing=0 cellpadding=1 border=0>
<tr><td ALIGN=middle><a class='linkbox' href="/news/" TITLE="Rubrique news"><img width=13 height=15 hspace=5 border=0 src=/inc/img/picto-news.gif ALT=#></A></td><td><a class='linkbox' href="/news/" TITLE="News">News</a></td></tr>
<tr><td ALIGN=middle><a class='linkbox' href="/mail/" TITLE="Rubrique mail"><img width=15 height=11 hspace=5 border=0 src=/inc/img/picto-mail.gif ALT=#></A></td><td><a class='linkbox' href="/mail/" TITLE="Mailing list archive">Mailing-list</a></td></tr>
<tr><td ALIGN=middle><a class='linkbox' href="/docs/" TITLE="Rubrique docs"><img width=14 height=16 hspace=5 border=0 src=/inc/img/picto-docs.gif ALT=#></A></td><td><a class='linkbox' href="/docs/" TITLE="Documentation">Documentation</a></td></tr>
<tr><td ALIGN=middle><a class='linkbox' href="/cvs/" TITLE="Rubrique cvs"><img width=13 height=17 hspace=5 border=0 src=/inc/img/picto-cvs.gif ALT=#></A></td><td><a class='linkbox' href="/cvs/" TITLE="CVS Web">CVS</a></td></tr>
<tr><td ALIGN=middle><a class='linkbox' href="/bugs/" TITLE="Rubrique bugs"><img width=20 height=16 hspace=5 border=0 src=/inc/img/picto-bugs.gif ALT=#></A></td><td><a class='linkbox' href="/bugs/" TITLE="Bugtracking">Bugs</a></td></tr>
<tr><td ALIGN=middle><a class='linkbox' href="/GPL.php3" TITLE="Rubrique license"><img width=18 height=12 hspace=5 border=0 src=/inc/img/picto-gpl.gif ALT=#></A></td><td><a class='linkbox' href="/GPL.php3" TITLE="License">License</a></td></tr>
</TABLE>
</TD></TR></TABLE></TD></TR></TABLE>
<!------ End Box ------>
</TD>
<TD WIDTH=15><IMG SRC="/inc/img/pixel.gif" WIDTH="16" HEIGHT="16" BORDER=0 ALT=""></TD>
<TD ALIGN=left valign=top><IMG SRC="/inc/img/pixel.gif" WIDTH="140" HEIGHT="10" BORDER=0 ALT="">
<!-- title -->
<TABLE background="/inc/img/redline.gif" CELLSPACING=0 CELLPADDING=0 BORDER=0 width=100%><tr><td>
<A HREF="/docs/"><img src="/inc/img/t_docs.gif" ALT="Docs" HEIGHT=20 BORDER=0></A>
</td><td><IMG SRC="/inc/img/pixel.gif" WIDTH="1" HEIGHT="1" BORDER=0 ALT="">
</td></tr></table>
<!-- block -->
<TABLE bgcolor="#dddddd" CELLSPACING=0 CELLPADDING=0 BORDER=0 width=100%><tr><td width=1% valign=middle><img width=6 height=14 hspace=2 vspace=2 src="/inc/img/reddots.gif"></TD>
<TD><B>Documentation</B></TD>
<TD ALIGN=RIGHT> </td>
</tr></table>
<!-- Generated by Doxygen 1.2.14 -->
<center>
<a class="qindex" href="index.html">Main Page</a> <a class="qindex" href="namespaces.html">Namespace List</a> <a class="qindex" href="hierarchy.html">Class Hierarchy</a> <a class="qindex" href="classes.html">Alphabetical List</a> <a class="qindex" href="annotated.html">Compound List</a> <a class="qindex" href="files.html">File List</a> <a class="qindex" href="namespacemembers.html">Namespace Members</a> <a class="qindex" href="functions.html">Compound Members</a> <a class="qindex" href="globals.html">File Members</a> <a class="qindex" href="pages.html">Related Pages</a> <a class="qindexRef" doxygen="_cgi:/cgi-bin/nel-search.cgi" href="/cgi-bin/nel-search.cgi">Search</a> </center>
<hr><h1>shared_memory.cpp</h1><a href="shared__memory_8cpp.html">Go to the documentation of this file.</a><div class="fragment"><pre>00001
00007 <font class="comment">/* Copyright, 2000-2002 Nevrax Ltd.</font>
00008 <font class="comment"> *</font>
00009 <font class="comment"> * This file is part of NEVRAX NEL.</font>
00010 <font class="comment"> * NEVRAX NEL is free software; you can redistribute it and/or modify</font>
00011 <font class="comment"> * it under the terms of the GNU General Public License as published by</font>
00012 <font class="comment"> * the Free Software Foundation; either version 2, or (at your option)</font>
00013 <font class="comment"> * any later version.</font>
00014 <font class="comment"></font>
00015 <font class="comment"> * NEVRAX NEL is distributed in the hope that it will be useful, but</font>
00016 <font class="comment"> * WITHOUT ANY WARRANTY; without even the implied warranty of</font>
00017 <font class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU</font>
00018 <font class="comment"> * General Public License for more details.</font>
00019 <font class="comment"></font>
00020 <font class="comment"> * You should have received a copy of the GNU General Public License</font>
00021 <font class="comment"> * along with NEVRAX NEL; see the file COPYING. If not, write to the</font>
00022 <font class="comment"> * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,</font>
00023 <font class="comment"> * MA 02111-1307, USA.</font>
00024 <font class="comment"> */</font>
00025
00026 <font class="preprocessor">#include "<a class="code" href="stdmisc_8h.html">stdmisc.h</a>"</font>
00027 <font class="preprocessor">#include "<a class="code" href="shared__memory_8h.html">nel/misc/shared_memory.h</a>"</font>
00028
00029 <font class="preprocessor">#ifdef NL_OS_WINDOWS</font>
00030 <font class="preprocessor"></font><font class="preprocessor">#include <windows.h></font>
00031 <font class="preprocessor">#else</font>
00032 <font class="preprocessor"></font><font class="preprocessor"># include <sys/types.h></font>
00033 <font class="preprocessor"># include <sys/ipc.h></font>
00034 <font class="preprocessor"># include <sys/shm.h></font>
00035 <font class="preprocessor">#endif</font>
00036 <font class="preprocessor"></font>
00037 <font class="keyword">using</font> <font class="keyword">namespace </font>std;
00038
00039
00040 <font class="keyword">namespace </font>NLMISC {
00041
00042
00043 <font class="preprocessor">#ifdef NL_OS_WINDOWS</font>
00044 <font class="preprocessor"></font> <font class="comment">// Storage for file handles, necessary to close the handles</font>
00045 map<void*,HANDLE> AccessAddressesToHandles;
00046 <font class="preprocessor">#else</font>
00047 <font class="preprocessor"></font> <font class="comment">// Storage for shmid, necessary to destroy the segments</font>
00048 map<TSharedMemId, int> <a class="code" href="namespaceNLMISC.html#a202">SharedMemIdsToShmids</a>;
00049 <font class="preprocessor">#endif</font>
00050 <font class="preprocessor"></font>
00051
00052 <font class="comment">/*</font>
00053 <font class="comment"> * Create a shared memory segment</font>
00054 <font class="comment"> */</font>
<a name="l00055"></a><a class="code" href="classNLMISC_1_1CSharedMemory.html#d0">00055</a> <font class="keywordtype">void</font> *CSharedMemory::createSharedMemory( <a class="code" href="namespaceNLMISC.html#a176">TSharedMemId</a> sharedMemId, uint32 size )
00056 {
00057 <font class="preprocessor">#ifdef NL_OS_WINDOWS</font>
00058 <font class="preprocessor"></font>
00059 <font class="comment">// Create a file mapping backed by the virtual memory swap file (not a data file)</font>
00060 HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, size, sharedMemId );
00061 <font class="keywordflow">if</font> ( (hMapFile == NULL) || (GetLastError() == ERROR_ALREADY_EXISTS) )
00062 <font class="keywordflow">return</font> NULL;
00063
00064 <font class="comment">// Map the file into memory address space</font>
00065 <font class="keywordtype">void</font> *accessAddress = MapViewOfFile( hMapFile, FILE_MAP_ALL_ACCESS, 0, 0, 0 );
00066 AccessAddressesToHandles.insert( make_pair( accessAddress, hMapFile ) );
00067 <font class="keywordflow">return</font> accessAddress;
00068
00069 <font class="preprocessor">#else</font>
00070 <font class="preprocessor"></font>
00071 <font class="comment">// Create a shared memory segment</font>
00072 <font class="keywordtype">int</font> shmid = shmget( sharedMemId, size, IPC_CREAT | IPC_EXCL | 0666 );
00073 <font class="keywordflow">if</font> ( shmid == -1 )
00074 <font class="keywordflow">return</font> NULL;
00075 <a class="code" href="namespaceNLMISC.html#a202">SharedMemIdsToShmids</a>.insert( make_pair( sharedMemId, shmid ) );
00076
00077 <font class="comment">// Map the segment into memory address space</font>
00078 <font class="keywordtype">void</font> *accessAddress = (<font class="keywordtype">void</font>*)shmat( shmid, 0, 0 );
00079 <font class="keywordflow">if</font> ( accessAddress == (<font class="keywordtype">void</font>*)-1 )
00080 <font class="keywordflow">return</font> NULL;
00081 <font class="keywordflow">else</font>
00082 <font class="keywordflow">return</font> accessAddress;
00083 <font class="preprocessor">#endif</font>
00084 <font class="preprocessor"></font>}
00085
00086
00087 <font class="comment">/*</font>
00088 <font class="comment"> * Get access to an existing shared memory segment</font>
00089 <font class="comment"> */</font>
<a name="l00090"></a><a class="code" href="classNLMISC_1_1CSharedMemory.html#d1">00090</a> <font class="keywordtype">void</font> *CSharedMemory::accessSharedMemory( <a class="code" href="namespaceNLMISC.html#a176">TSharedMemId</a> sharedMemId )
00091 {
00092 <font class="preprocessor">#ifdef NL_OS_WINDOWS</font>
00093 <font class="preprocessor"></font>
00094 <font class="comment">// Open the existing file mapping by name</font>
00095 HANDLE hMapFile = OpenFileMapping( FILE_MAP_ALL_ACCESS, <font class="keyword">false</font>, sharedMemId );
00096 <font class="keywordflow">if</font> ( hMapFile == NULL )
00097 <font class="keywordflow">return</font> NULL;
00098
00099 <font class="comment">// Map the file into memory address space</font>
00100 <font class="keywordtype">void</font> *accessAddress = MapViewOfFile( hMapFile, FILE_MAP_ALL_ACCESS, 0, 0, 0 );
00101 AccessAddressesToHandles.insert( make_pair( accessAddress, hMapFile ) );
00102 <font class="keywordflow">return</font> accessAddress;
00103
00104 <font class="preprocessor">#else</font>
00105 <font class="preprocessor"></font>
00106 <font class="comment">// Open an existing shared memory segment</font>
00107 <font class="keywordtype">int</font> shmid = shmget( sharedMemId, 0, 0666 );
00108 <font class="keywordflow">if</font> ( shmid == -1 )
00109 <font class="keywordflow">return</font> NULL;
00110
00111 <font class="comment">// Map the segment into memory address space</font>
00112 <font class="keywordtype">void</font> *accessAddress = (<font class="keywordtype">void</font>*)shmat( shmid, 0, 0 );
00113 <font class="keywordflow">if</font> ( accessAddress == (<font class="keywordtype">void</font>*)-1 )
00114 <font class="keywordflow">return</font> NULL;
00115 <font class="keywordflow">else</font>
00116 <font class="keywordflow">return</font> accessAddress;
00117
00118 <font class="preprocessor">#endif</font>
00119 <font class="preprocessor"></font>}
00120
00121
00122 <font class="comment">/*</font>
00123 <font class="comment"> * Close a shared memory segment</font>
00124 <font class="comment"> */</font>
<a name="l00125"></a><a class="code" href="classNLMISC_1_1CSharedMemory.html#d2">00125</a> <font class="keywordtype">bool</font> CSharedMemory::closeSharedMemory( <font class="keywordtype">void</font> *accessAddress )
00126 {
00127 <font class="preprocessor">#ifdef NL_OS_WINDOWS</font>
00128 <font class="preprocessor"></font>
00129 <font class="comment">// Unmap the file from memory address space</font>
00130 <font class="keywordflow">if</font> ( UnmapViewOfFile( accessAddress ) == 0 )
00131 <font class="keywordflow">return</font> <font class="keyword">false</font>;
00132
00133 <font class="comment">// Close the corresponding handle</font>
00134 map<void*,HANDLE>::iterator im = AccessAddressesToHandles.find( accessAddress );
00135 <font class="keywordflow">if</font> ( im != AccessAddressesToHandles.end() )
00136 {
00137 CloseHandle( (*im).second );
00138 AccessAddressesToHandles.erase( im );
00139 <font class="keywordflow">return</font> <font class="keyword">true</font>;
00140 }
00141 <font class="keywordflow">else</font>
00142 {
00143 <font class="keywordflow">return</font> <font class="keyword">false</font>;
00144 }
00145
00146 <font class="preprocessor">#else</font>
00147 <font class="preprocessor"></font>
00148 <font class="comment">// Detach the shared memory segment</font>
00149 <font class="keywordflow">return</font> ( shmdt( accessAddress ) != -1 );
00150
00151 <font class="preprocessor">#endif</font>
00152 <font class="preprocessor"></font>}
00153
00154
00155 <font class="comment">/*</font>
00156 <font class="comment"> * Destroy a shared memory segment (to call only by the process that created the segment)</font>
00157 <font class="comment"> * Note: does nothing under Windows, it is automatic.</font>
00158 <font class="comment"> */</font>
<a name="l00159"></a><a class="code" href="classNLMISC_1_1CSharedMemory.html#d3">00159</a> <font class="keywordtype">void</font> CSharedMemory::destroySharedMemory( <a class="code" href="namespaceNLMISC.html#a176">TSharedMemId</a> sharedMemId, <font class="keywordtype">bool</font> force )
00160 {
00161 <font class="preprocessor">#ifndef NL_OS_WINDOWS</font>
00162 <font class="preprocessor"></font> <font class="comment">// Set the segment to auto-destroying (when the last process detaches)</font>
00163 map<TSharedMemId,int>::iterator im = <a class="code" href="namespaceNLMISC.html#a202">SharedMemIdsToShmids</a>.find( sharedMemId );
00164 <font class="keywordflow">if</font> ( im != <a class="code" href="namespaceNLMISC.html#a202">SharedMemIdsToShmids</a>.end() )
00165 {
00166 <font class="comment">// Destroy the segment created before</font>
00167 shmctl( (*im).second, IPC_RMID, 0 );
00168 <a class="code" href="namespaceNLMISC.html#a202">SharedMemIdsToShmids</a>.erase( im );
00169 }
00170 <font class="keywordflow">else</font> <font class="keywordflow">if</font> ( force )
00171 {
00172 <font class="comment">// Open and destroy the segment</font>
00173 <font class="keywordtype">int</font> shmid = shmget( sharedMemId, 0, 0666 );
00174 <font class="keywordflow">if</font> ( shmid != -1 )
00175 {
00176 <font class="comment">// Destroy the segment</font>
00177 shmctl( shmid, IPC_RMID, 0 );
00178 }
00179 }
00180 <font class="preprocessor">#endif</font>
00181 <font class="preprocessor"></font>}
00182
00183
00184 } <font class="comment">// NLMISC</font>
</pre></div>
<!-- footer -->
<BR><FONT Size=+5> </FONT>
</TD>
<TD WIDTH=15><IMG SRC=/inc/img/pixel.gif WIDTH=15 HEIGHT=15 BORDER=0 ALT=""></TD>
</TR>
</TABLE>
</BODY>
</HTML>
|
