[Quickfix-developers] Constructing msg from corrupted string

[Brendan B. B. <br...@ka...>]

Hi,

Suppose a FIX::Message is constructed from a string and suppose the
string is a concatenation of two FIX messages (e.g. suppose you're
reading from a log of FIX msgs which somehow was corrupted).

In Message::setString(const std::string, bool, const DataDictionary
*), w/o the two lines I've added below, this will be an infinite loop
as pos will increase through the massage which corresponds to the
'first' message and then reset to a low value when it reaches the
'second' message in the string i.e.  pos will never be >=
string.size().

  while ( pos < string.size() )
  {
    FieldBase field = extractField( string, pos, pDataDictionary );
    // Begin brendan, 9/2/04
    if (pos < pos2) throw InvalidMessage();
    else pos2 = pos;
    // End brendan, 9/2/04

    if ( count < 3 && headerOrder[ count++ ] != field.getField() )
      if ( doValidation ) throw InvalidMessage();
    ...
  }

Regards,
Brendan