47 lines
1.5 KiB
JavaScript
47 lines
1.5 KiB
JavaScript
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var log = console.log
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, dlength = 700
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, stime = 0
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, boundary = new Buffer( 57 )
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// build test data to parse
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, data = ( function () {
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var test = new Buffer( dlength * 1024 * 1024)
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, t = 0
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, tlen = test.length
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;
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log( '- now building a %d GB test buffer..', ( dlength / 1024 ).toFixed( 2 ) );
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for ( ; ++t < tlen; ) {
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test[ t ] = t % 256;
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}
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log( '- test buffer created..' );
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return test;
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} )()
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// crook parse method
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, magicParse = function ( pattern, data ) {
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var i = 0
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, dlen = data.length
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, plen = pattern.length
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, pchar = pattern[ plen - 1 ]
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;
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log( '- now parsing test buffer with magic algorithm..' );
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for( stime = Date.now(); i < dlen; i += plen ) {
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/*
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* access data and compare current byte with the last byte of pattern,
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* then skip plen bytes, no other comparison.
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* best performance O(n/m)
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*/
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if( pchar === data[ i ] ) {
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// ..
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}
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}
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return [];
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}
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, results = magicParse( boundary, data )
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, duration = ( Date.now() - stime )
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, datarate = ( ( dlength / duration ) * ( 7.8125 ) )
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;
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log( '- elapsed time is; %d millis (I\'m the best!)', duration );
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log( '- datarate is: %d Gbit/sec (Magic!)', ( datarate ).toFixed( 2 ) );
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log( '- results: 0 found (Sorry, I\'m a crook!)' );
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