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diff --git a/docs/doxygen/nel/a03382.html b/docs/doxygen/nel/a03382.html new file mode 100644 index 00000000..1811e263 --- /dev/null +++ b/docs/doxygen/nel/a03382.html @@ -0,0 +1,328 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"> +<title>NeL: NLMISC::CSharedMemory class Reference</title> +<link href="doxygen.css" rel="stylesheet" type="text/css"> +</head><body> +<!-- Generated by Doxygen 1.3.6 --> +<div class="qindex"> <form class="search" action="search.php" method="get"> +<a class="qindex" href="main.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">Data Structures</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">Data Fields</a> | <a class="qindex" href="globals.html">Globals</a> | <a class="qindex" href="pages.html">Related Pages</a> | <span class="search"><u>S</u>earch for <input class="search" type="text" name="query" value="" size="20" accesskey="s"/></span></form></div> +<h1>NLMISC::CSharedMemory Class Reference</h1><code>#include <<a class="el" href="a06383.html">shared_memory.h</a>></code> +<p> +<hr><a name="_details"></a><h2>Detailed Description</h2> +Encapsulation of shared memory APIs. Using file mapping under Windows, System V shared memory (shm) under Linux.<p> +Note: under Linux, an option could be added to prevent a segment to be swapped out.<p> +<dl compact><dt><b>Author:</b></dt><dd>Olivier Cado <p> +Nevrax France </dd></dl> +<dl compact><dt><b>Date:</b></dt><dd>2002 </dd></dl> + +<p> + +<p> +Definition at line <a class="el" href="a06383.html#l00068">68</a> of file <a class="el" href="a06383.html">shared_memory.h</a>.<table border=0 cellpadding=0 cellspacing=0> +<tr><td></td></tr> +<tr><td colspan=2><br><h2>Static Public Member Functions</h2></td></tr> +<tr><td class="memItemLeft" nowrap align=right valign=top>void * </td><td class="memItemRight" valign=bottom><a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye0">accessSharedMemory</a> (<a class="el" href="a05378.html#a232">TSharedMemId</a> sharedMemId)</td></tr> + +<tr><td class="memItemLeft" nowrap align=right valign=top>bool </td><td class="memItemRight" valign=bottom><a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye1">closeSharedMemory</a> (void *accessAddress)</td></tr> + +<tr><td class="memItemLeft" nowrap align=right valign=top>void * </td><td class="memItemRight" valign=bottom><a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye2">createSharedMemory</a> (<a class="el" href="a05378.html#a232">TSharedMemId</a> sharedMemId, <a class="el" href="a04558.html#a11">uint32</a> <a class="el" href="a04223.html#a587">size</a>)</td></tr> + +<tr><td class="memItemLeft" nowrap align=right valign=top>void </td><td class="memItemRight" valign=bottom><a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye3">destroySharedMemory</a> (<a class="el" href="a05378.html#a232">TSharedMemId</a> sharedMemId, bool force=false)</td></tr> + +</table> +<hr><h2>Member Function Documentation</h2> +<a class="anchor" name="NLMISC_1_1CSharedMemorye0" doxytag="NLMISC::CSharedMemory::accessSharedMemory" ></a><p> +<table class="mdTable" width="100%" cellpadding="2" cellspacing="0"> + <tr> + <td class="mdRow"> + <table cellpadding="0" cellspacing="0" border="0"> + <tr> + <td class="md" nowrap valign="top"> void * NLMISC::CSharedMemory::accessSharedMemory </td> + <td class="md" valign="top">( </td> + <td class="md" nowrap valign="top"><a class="el" href="a05378.html#a232">TSharedMemId</a> </td> + <td class="mdname1" valign="top" nowrap> <em>sharedMemId</em> </td> + <td class="md" valign="top"> ) </td> + <td class="md" nowrap><code> [static]</code></td> + </tr> + + </table> + </td> + </tr> +</table> +<table cellspacing=5 cellpadding=0 border=0> + <tr> + <td> + + </td> + <td> + +<p> +Get access to an existing shared memory segment. The id must be used. <dl compact><dt><b>Returns:</b></dt><dd>Access address of the segment. Its size was determined at the creation.</dd></dl> + +<p> +Definition at line <a class="el" href="a06382.html#l00100">100</a> of file <a class="el" href="a06382.html">shared_memory.cpp</a>. +<p> +References <a class="el" href="a06383.html#l00041">NLMISC::TSharedMemId</a>. +<p> +<div class="fragment"><pre>00101 { +00102 <span class="preprocessor">#ifdef NL_OS_WINDOWS</span> +00103 <span class="preprocessor"></span> +00104 <span class="comment">// Open the existing file mapping by name</span> +00105 HANDLE hMapFile = OpenFileMapping( FILE_MAP_ALL_ACCESS, <span class="keyword">false</span>, sharedMemId ); +00106 <span class="keywordflow">if</span> ( hMapFile == NULL ) +00107 <span class="keywordflow">return</span> NULL; +00108 <span class="comment">//nldebug( "SHDMEM: Opening smid %s --> mapFile %p", sharedMemId, hMapFile );</span> +00109 +00110 <span class="comment">// Map the file into memory address space</span> +00111 <span class="keywordtype">void</span> *accessAddress = MapViewOfFile( hMapFile, FILE_MAP_ALL_ACCESS, 0, 0, 0 ); +00112 AccessAddressesToHandles.insert( make_pair( accessAddress, hMapFile ) ); +00113 <span class="keywordflow">return</span> accessAddress; +00114 +00115 <span class="preprocessor">#else</span> +00116 <span class="preprocessor"></span> +00117 <span class="comment">// Open an existing shared memory segment</span> +00118 <span class="keywordtype">int</span> shmid = shmget( sharedMemId, 0, 0666 ); +00119 <span class="keywordflow">if</span> ( shmid == -1 ) +00120 <span class="keywordflow">return</span> NULL; +00121 +00122 <span class="comment">// Map the segment into memory address space</span> +00123 <span class="keywordtype">void</span> *accessAddress = (<span class="keywordtype">void</span>*)shmat( shmid, 0, 0 ); +00124 <span class="keywordflow">if</span> ( accessAddress == (<span class="keywordtype">void</span>*)-1 ) +00125 <span class="keywordflow">return</span> NULL; +00126 <span class="keywordflow">else</span> +00127 <span class="keywordflow">return</span> accessAddress; +00128 +00129 <span class="preprocessor">#endif</span> +00130 <span class="preprocessor"></span>} +</pre></div> </td> + </tr> +</table> +<a class="anchor" name="NLMISC_1_1CSharedMemorye1" doxytag="NLMISC::CSharedMemory::closeSharedMemory" ></a><p> +<table class="mdTable" width="100%" cellpadding="2" cellspacing="0"> + <tr> + <td class="mdRow"> + <table cellpadding="0" cellspacing="0" border="0"> + <tr> + <td class="md" nowrap valign="top"> bool NLMISC::CSharedMemory::closeSharedMemory </td> + <td class="md" valign="top">( </td> + <td class="md" nowrap valign="top">void * </td> + <td class="mdname1" valign="top" nowrap> <em>accessAddress</em> </td> + <td class="md" valign="top"> ) </td> + <td class="md" nowrap><code> [static]</code></td> + </tr> + + </table> + </td> + </tr> +</table> +<table cellspacing=5 cellpadding=0 border=0> + <tr> + <td> + + </td> + <td> + +<p> +Close a shared memory segment, given the address returned by <a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye2">createSharedMemory()</a> or <a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye0">accessSharedMemory()</a>. Must be called by each process that called <a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye2">createSharedMemory()</a> or <a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye0">accessSharedMemory()</a>. +<p> +Definition at line <a class="el" href="a06382.html#l00136">136</a> of file <a class="el" href="a06382.html">shared_memory.cpp</a>. +<p> +References <a class="el" href="a05622.html#l00135">nlwarning</a>. +<p> +<div class="fragment"><pre>00137 { +00138 <span class="preprocessor">#ifdef NL_OS_WINDOWS</span> +00139 <span class="preprocessor"></span> +00140 <span class="keywordtype">bool</span> result = <span class="keyword">true</span>; +00141 +00142 <span class="comment">// Unmap the file from memory address space</span> +00143 <span class="keywordflow">if</span> ( UnmapViewOfFile( accessAddress ) == 0 ) +00144 { +00145 <a class="code" href="a04199.html#a2">nlwarning</a>( <span class="stringliteral">"SHDMEM: UnmapViewOfFile failed: error %u"</span>, GetLastError() ); +00146 result = <span class="keyword">false</span>; +00147 } +00148 +00149 <span class="comment">// Close the corresponding handle</span> +00150 map<void*,HANDLE>::iterator im = AccessAddressesToHandles.find( accessAddress ); +00151 <span class="keywordflow">if</span> ( im != AccessAddressesToHandles.end() ) +00152 { +00153 <span class="comment">//nldebug( "SHDMEM: CloseHandle mapFile %u", (*im).second );</span> +00154 <span class="keywordflow">if</span> ( ! CloseHandle( (*im).second ) ) +00155 <a class="code" href="a04199.html#a2">nlwarning</a>( <span class="stringliteral">"SHDMEM: CloseHandle failed: error %u, mapFile %u"</span>, GetLastError(), (*im).second ); +00156 AccessAddressesToHandles.erase( im ); +00157 <span class="keywordflow">return</span> result; +00158 } +00159 <span class="keywordflow">else</span> +00160 { +00161 <span class="keywordflow">return</span> <span class="keyword">false</span>; +00162 } +00163 +00164 <span class="preprocessor">#else</span> +00165 <span class="preprocessor"></span> +00166 <span class="comment">// Detach the shared memory segment</span> +00167 <span class="keywordflow">return</span> ( shmdt( accessAddress ) != -1 ); +00168 +00169 <span class="preprocessor">#endif</span> +00170 <span class="preprocessor"></span>} +</pre></div> </td> + </tr> +</table> +<a class="anchor" name="NLMISC_1_1CSharedMemorye2" doxytag="NLMISC::CSharedMemory::createSharedMemory" ></a><p> +<table class="mdTable" width="100%" cellpadding="2" cellspacing="0"> + <tr> + <td class="mdRow"> + <table cellpadding="0" cellspacing="0" border="0"> + <tr> + <td class="md" nowrap valign="top"> void * NLMISC::CSharedMemory::createSharedMemory </td> + <td class="md" valign="top">( </td> + <td class="md" nowrap valign="top"><a class="el" href="a05378.html#a232">TSharedMemId</a> </td> + <td class="mdname" nowrap> <em>sharedMemId</em>, </td> + </tr> + <tr> + <td class="md" nowrap align="right"></td> + <td></td> + <td class="md" nowrap><a class="el" href="a04558.html#a11">uint32</a> </td> + <td class="mdname" nowrap> <em>size</em></td> + </tr> + <tr> + <td></td> + <td class="md">) </td> + <td class="md" colspan="2"><code> [static]</code></td> + </tr> + + </table> + </td> + </tr> +</table> +<table cellspacing=5 cellpadding=0 border=0> + <tr> + <td> + + </td> + <td> + +<p> +Create a shared memory segment and get access to it. The id must not be used. The id 0x3a732235 is used by the NeL memory manager. <dl compact><dt><b>Returns:</b></dt><dd>Access address of the segment of the choosen size</dd></dl> + +<p> +Definition at line <a class="el" href="a06382.html#l00055">55</a> of file <a class="el" href="a06382.html">shared_memory.cpp</a>. +<p> +References <a class="el" href="a05622.html#l00135">nlwarning</a>, <a class="el" href="a06382.html#l00048">NLMISC::SharedMemIdsToShmids</a>, <a class="el" href="a05646.html#l00645">size</a>, <a class="el" href="a06383.html#l00041">NLMISC::TSharedMemId</a>, and <a class="el" href="a05981.html#l00100">uint32</a>. +<p> +<div class="fragment"><pre>00056 { +00057 <span class="preprocessor">#ifdef NL_OS_WINDOWS</span> +00058 <span class="preprocessor"></span> +00059 <span class="comment">// Create a file mapping backed by the virtual memory swap file (not a data file)</span> +00060 HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, size, sharedMemId ); +00061 <span class="keywordflow">if</span> ( (hMapFile == NULL) || (GetLastError() == ERROR_ALREADY_EXISTS) ) +00062 { +00063 <a class="code" href="a04199.html#a2">nlwarning</a>( <span class="stringliteral">"SHDMEM: Cannot create file mapping: error %u, mapFile %p"</span>, GetLastError(), hMapFile ); +00064 <span class="keywordflow">return</span> NULL; +00065 } +00066 <span class="comment">//else</span> +00067 <span class="comment">// nldebug( "SHDMEM: Creating smid %s --> mapFile %p", sharedMemId, hMapFile );</span> +00068 +00069 +00070 <span class="comment">// Map the file into memory address space</span> +00071 <span class="keywordtype">void</span> *accessAddress = MapViewOfFile( hMapFile, FILE_MAP_ALL_ACCESS, 0, 0, 0 ); +00072 AccessAddressesToHandles.insert( make_pair( accessAddress, hMapFile ) ); +00073 <span class="comment">/*if ( accessAddress == NULL )</span> +00074 <span class="comment"> {</span> +00075 <span class="comment"> nlwarning( "SHDMEM: Cannot map view of file: error %u", GetLastError() );</span> +00076 <span class="comment"> }*/</span> +00077 <span class="keywordflow">return</span> accessAddress; +00078 +00079 <span class="preprocessor">#else</span> +00080 <span class="preprocessor"></span> +00081 <span class="comment">// Create a shared memory segment</span> +00082 <span class="keywordtype">int</span> shmid = shmget( sharedMemId, size, IPC_CREAT | IPC_EXCL | 0666 ); +00083 <span class="keywordflow">if</span> ( shmid == -1 ) +00084 <span class="keywordflow">return</span> NULL; +00085 <a class="code" href="a05378.html#a36">SharedMemIdsToShmids</a>.insert( make_pair( sharedMemId, shmid ) ); +00086 +00087 <span class="comment">// Map the segment into memory address space</span> +00088 <span class="keywordtype">void</span> *accessAddress = (<span class="keywordtype">void</span>*)shmat( shmid, 0, 0 ); +00089 <span class="keywordflow">if</span> ( accessAddress == (<span class="keywordtype">void</span>*)-1 ) +00090 <span class="keywordflow">return</span> NULL; +00091 <span class="keywordflow">else</span> +00092 <span class="keywordflow">return</span> accessAddress; +00093 <span class="preprocessor">#endif</span> +00094 <span class="preprocessor"></span>} +</pre></div> </td> + </tr> +</table> +<a class="anchor" name="NLMISC_1_1CSharedMemorye3" doxytag="NLMISC::CSharedMemory::destroySharedMemory" ></a><p> +<table class="mdTable" width="100%" cellpadding="2" cellspacing="0"> + <tr> + <td class="mdRow"> + <table cellpadding="0" cellspacing="0" border="0"> + <tr> + <td class="md" nowrap valign="top"> void NLMISC::CSharedMemory::destroySharedMemory </td> + <td class="md" valign="top">( </td> + <td class="md" nowrap valign="top"><a class="el" href="a05378.html#a232">TSharedMemId</a> </td> + <td class="mdname" nowrap> <em>sharedMemId</em>, </td> + </tr> + <tr> + <td class="md" nowrap align="right"></td> + <td></td> + <td class="md" nowrap>bool </td> + <td class="mdname" nowrap> <em>force</em> = false</td> + </tr> + <tr> + <td></td> + <td class="md">) </td> + <td class="md" colspan="2"><code> [static]</code></td> + </tr> + + </table> + </td> + </tr> +</table> +<table cellspacing=5 cellpadding=0 border=0> + <tr> + <td> + + </td> + <td> + +<p> +Destroy a shared memory segment (must be called by the process that created the segment, not by the accessors).<p> +"Rescue feature": set "force" to true if a segment was created and left out of control (meaning a new <a class="el" href="a03382.html#NLMISC_1_1CSharedMemorye2">createSharedMemory()</a> with the same sharedMemId fails), but before, make sure the segment really belongs to you!<p> +Note: this method does nothing under Windows, destroying is automatic. +<p> +Definition at line <a class="el" href="a06382.html#l00177">177</a> of file <a class="el" href="a06382.html">shared_memory.cpp</a>. +<p> +References <a class="el" href="a06382.html#l00048">NLMISC::SharedMemIdsToShmids</a>, and <a class="el" href="a06383.html#l00041">NLMISC::TSharedMemId</a>. +<p> +<div class="fragment"><pre>00178 { +00179 <span class="preprocessor">#ifndef NL_OS_WINDOWS</span> +00180 <span class="preprocessor"></span> <span class="comment">// Set the segment to auto-destroying (when the last process detaches)</span> +00181 map<TSharedMemId,int>::iterator im = <a class="code" href="a05378.html#a36">SharedMemIdsToShmids</a>.find( sharedMemId ); +00182 <span class="keywordflow">if</span> ( im != <a class="code" href="a05378.html#a36">SharedMemIdsToShmids</a>.end() ) +00183 { +00184 <span class="comment">// Destroy the segment created before</span> +00185 shmctl( (*im).second, IPC_RMID, 0 ); +00186 <a class="code" href="a05378.html#a36">SharedMemIdsToShmids</a>.erase( im ); +00187 } +00188 <span class="keywordflow">else</span> <span class="keywordflow">if</span> ( force ) +00189 { +00190 <span class="comment">// Open and destroy the segment</span> +00191 <span class="keywordtype">int</span> shmid = shmget( sharedMemId, 0, 0666 ); +00192 <span class="keywordflow">if</span> ( shmid != -1 ) +00193 { +00194 <span class="comment">// Destroy the segment</span> +00195 shmctl( shmid, IPC_RMID, 0 ); +00196 } +00197 } +00198 <span class="preprocessor">#endif</span> +00199 <span class="preprocessor"></span>} +</pre></div> </td> + </tr> +</table> +<hr>The documentation for this class was generated from the following files:<ul> +<li><a class="el" href="a06383.html">shared_memory.h</a><li><a class="el" href="a06382.html">shared_memory.cpp</a></ul> +<hr size="1"><address style="align: right;"><small>Generated on Tue Mar 16 13:32:41 2004 for NeL by +<a href="http://www.doxygen.org/index.html"> +<img src="doxygen.png" alt="doxygen" align="middle" border=0 > +</a>1.3.6 </small></address> +</body> +</html> |