//C++ source code in Scanner.cpp

 

 

#include <iostream>

using namespace std;

 

#include "Scanner.h"

#include "trie.h"

 

Scanner::Scanner()

{

shortest_sig=UINT_MAX;

longest_sig=0;

}

 

Scanner::Scanner(istream &in)

{

Scanner();

LoadDatabase(in);

}

 

Scanner::~Scanner()

{

while (m_Patterns.empty() == false)

{

delete[] m_Patterns.front().m_Pattern;

m_Patterns.pop_front();

}

}

 

void Scanner::LoadDatabase(istream &in)

{

string buffer;

 

getline(in, buffer);

while ( in.fail() == false )

{

string::size_type pos = buffer.find('=');

if ( pos != string::npos )

{

string name = buffer.substr( 0, pos );

string scan_string = buffer.substr( pos+1 );

 

// Add to the string search list

Add( name, scan_string );

}

getline(in, buffer);

}

    clog << endl;

m_Trie.Initialise();

m_Trie.Reset();

}

 

 

inline 

void Scanner::Add( const string &name, const string &sig)

{

Pattern pat; 

pat.m_Name = name; 

size_t pattern_len = sig.length() / 2;

size_t siglen = sig.length();

pat.m_Pattern = new unsigned char[ pattern_len ];

pat.m_Len = 0;

char d[3], *end; d[2]='\0';

 

for (size_t i = 0; i < siglen; )

{

d[0] = sig.at(i); d[1] = sig.at(i+1);

if ( isalnum(d[0]) && isalnum(d[1]) )

{

pat.m_Pattern[ pat.m_Len ] = (unsigned char) strtoul(d, &end, 16);

i+=2;

pat.m_Len++;

}

else

{

throw runtime_error("not a digit, while parsing database"); // Not a digit

}

}

 

if ( pattern_len < shortest_sig )

shortest_sig = pattern_len;

if ( pattern_len > longest_sig )

longest_sig = pattern_len;

 

m_Patterns.push_back( pat );

clog << "Adding " << m_Patterns.back().m_Name << "to search trie" << endl;

m_Trie.Add( &m_Patterns.back() ); // Add string to the Trie

}

 

bool Scanner::Find(BlockBuffer *b, list<const Pattern*> **patterns)

{

return m_Trie.Find( b, patterns );

}