<?php
    //grab all the file contents
    $contents = file_get_contents($log_dir.'catchall.txt');
    //split it up by three newlines - this is particular to the 
    //way I actually wrote the log in the first place
    $split = explode("\n\n\n",$contents);
    //setup a few variables we'll need below
    $all_packets = array();
    $cur_packet  = NULL;
    $cur_data    = NULL;
    //foreach chunk of data
    foreach($split as $packet)
    {   
        //split into individual lines
        $lines = explode("\n",$packet);
        //for each line
        foreach($lines as $line)
        {   
            //if this is the line with the timestamp and ip address
            if(preg_match('/[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+ [0-9]+-[0-9]+-[0-9]+ [0-9]+:[0-9]+:[0-9]+/',$line))
            {   
                //if we have already started
                if($cur_packet !== NULL)
                    //store the information for the previous packet
                    $all_packets[] = $cur_packet;
                //initialise a new packet
                $cur_packet = array();
                $cur_packet['data'] = array();
                $cur_packet['origin'] = $line;
            }
            //if this line contains key => value data
            else if(preg_match('/^.*\[(.*)\] => (.*)/',$line,$matches))
                //store it in the current data array
                $cur_data[$matches[1]] = $matches[2];
            //if this is the start of a print_r
            else if(trim($line) === '(')
                //create a new current data array
                $cur_data = array();
            //if this is the end of a print_r
            else if(trim($line) === ')')
            {   
                //store the current data array of key/value pairs
                $cur_packet['data'][] = $cur_data;
            }
        }
    }
    //store the last packet
    $all_packets[] = $cur_packet;

    //now you should be able to run something like:
    //
    //php parse.php > todiff && diff todiff $log_dir.catchall.txt
    //
    //in order to verify that your parser was correct
    foreach($all_packets as $packet)
    {   
        echo $packet['origin'].PHP_EOL.PHP_EOL;

        foreach($packet['data'] as $data)
            print_r($data);

        echo PHP_EOL.PHP_EOL;
    }