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POEfficient parsing of mmap file
 

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    <p>Following is the code for creating a memory map file using boost.</p> <pre><code>boost::iostreams::mapped_file_source file; boost::iostreams::mapped_file_params param; param.path = "\\..\\points.pts"; //! Filepath file.open(param, fileSize); if(file.is_open()) { //! Access the buffer and populate the ren point buffer const char* pData = file.data(); char* pData1 = const_cast&lt;char*&gt;(pData); //! this gives me all the data from Mmap file std::vector&lt;RenPoint&gt; readPoints; ParseData( pData1, readPoints); } </code></pre> <p>The implementation of ParseData is as follows </p> <pre><code>void ParseData ( char* pbuffer , std::vector&lt;RenPoint&gt;&gt;&amp; readPoints) { if(!pbuffer) throw std::logic_error("no Data in memory mapped file"); stringstream strBuffer; strBuffer &lt;&lt; pbuffer; //! Get the max number of points in the pts file std::string strMaxPts; std::getline(strBuffer,strMaxPts,'\n'); auto nSize = strMaxPts.size(); unsigned nMaxNumPts = GetValue&lt;unsigned&gt;(strMaxPts); readPoints.clear(); //! Offset buffer pbuffer += nSize; strBuffer &lt;&lt; pbuffer; std::string cur_line; while(std::getline(strBuffer, cur_line,'\n')) { //! How do I read the data from mmap file directly and populate my renpoint structure int yy = 0; } //! Working but very slow /*while (std::getline(strBuffer,strMaxPts,'\n')) { std::vector&lt;string&gt; fragments; istringstream iss(strMaxPts); copy(istream_iterator&lt;string&gt;(iss), istream_iterator&lt;string&gt;(), back_inserter&lt;vector&lt;string&gt;&gt;(fragments)); //! Logic to populate the structure after getting data back from fragments readPoints.push_back(pt); }*/ } </code></pre> <p>I have say a minimum of 1 million points in my data structure and I want to optimize my parsing. Any ideas ? </p>
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