Marius van Witzenburg

Apache Error Codes

mariusvw — Fri, 11 Nov 2011 15:10:37 +0000

With the function below you can add your own custom actions to error statuses of Apache.

Lets say you want a custom 404 error page. You could redirect a user upon a 404 error or show a complete different layout.

/**
 * HTTP Protocol defined status codes
 * @param int $num
 */
function HTTPStatus($num) {
   static $http = array (
       100 => "HTTP/1.1 100 Continue",
       101 => "HTTP/1.1 101 Switching Protocols",
       200 => "HTTP/1.1 200 OK",
       201 => "HTTP/1.1 201 Created",
       202 => "HTTP/1.1 202 Accepted",
       203 => "HTTP/1.1 203 Non-Authoritative Information",
       204 => "HTTP/1.1 204 No Content",
       205 => "HTTP/1.1 205 Reset Content",
       206 => "HTTP/1.1 206 Partial Content",
       300 => "HTTP/1.1 300 Multiple Choices",
       301 => "HTTP/1.1 301 Moved Permanently",
       302 => "HTTP/1.1 302 Found",
       303 => "HTTP/1.1 303 See Other",
       304 => "HTTP/1.1 304 Not Modified",
       305 => "HTTP/1.1 305 Use Proxy",
       307 => "HTTP/1.1 307 Temporary Redirect",
       400 => "HTTP/1.1 400 Bad Request",
       401 => "HTTP/1.1 401 Unauthorized",
       402 => "HTTP/1.1 402 Payment Required",
       403 => "HTTP/1.1 403 Forbidden",
       404 => "HTTP/1.1 404 Not Found",
       405 => "HTTP/1.1 405 Method Not Allowed",
       406 => "HTTP/1.1 406 Not Acceptable",
       407 => "HTTP/1.1 407 Proxy Authentication Required",
       408 => "HTTP/1.1 408 Request Time-out",
       409 => "HTTP/1.1 409 Conflict",
       410 => "HTTP/1.1 410 Gone",
       411 => "HTTP/1.1 411 Length Required",
       412 => "HTTP/1.1 412 Precondition Failed",
       413 => "HTTP/1.1 413 Request Entity Too Large",
       414 => "HTTP/1.1 414 Request-URI Too Large",
       415 => "HTTP/1.1 415 Unsupported Media Type",
       416 => "HTTP/1.1 416 Requested range not satisfiable",
       417 => "HTTP/1.1 417 Expectation Failed",
       500 => "HTTP/1.1 500 Internal Server Error",
       501 => "HTTP/1.1 501 Not Implemented",
       502 => "HTTP/1.1 502 Bad Gateway",
       503 => "HTTP/1.1 503 Service Unavailable",
       504 => "HTTP/1.1 504 Gateway Time-out"
   );
 
   header($http[$num]);
}
?>

You can download this 404 error page example to play with.

How to easy CVS update your SRC and Ports tree with a simple Bash script (v2)

mariusvw — Mon, 26 Sep 2011 20:29:22 +0000

This is an update to this post: How to easy CVS update your SRC and Ports tree with a simple Bash script

I adjusted the script to use the local csup version of the FreeBSD World system and moved the cvsup files to /etc.

First install a simple tool to get the fastest cvs server

pkg_add -r fastest_cvsup

Or from Ports (if you have the collection already):

cd /usr/ports/sysutils/fastest_cvsup/
make install clean

Setup config and binary to easy update the repository for SRC and PORTS.

mkdir /etc/cvsup
cd /usr/share/examples/cvsup
cp stable-supfile /etc/cvsup
cp ports-supfile /etc/cvsup
cp doc-supfile /etc/cvsup
cd /etc/cvsup

Edit stable-supfile and change:

*default release=cvs tag=RELENG_8_2

Set this to your release version.

Edit /usr/local/sbin/runcvsup and add:

#!/bin/sh
arg=$@
sType="tld,nl" # Can be: all / tld / tld,nl,de,fr,us
if SERVER=`/usr/local/bin/fastest_cvsup -q -c $sType`; then
    echo "Using server: ${SERVER}"
    case "$arg" in
    "stable")
        echo "Updating: stable"
        /usr/bin/csup -L 2 -g -z -h ${SERVER} /etc/cvsup/stable-supfile
    ;;
    "ports")
        echo "Updating: ports"
        /usr/bin/csup -L 2 -g -z -h ${SERVER} /etc/cvsup/ports-supfile
    ;;
    "doc")  
        echo "Updating: doc"
        /usr/bin/csup -L 2 -g -z -h ${SERVER} /etc/cvsup/doc-supfile
    ;;
    *)
        echo "Updating: all"
        /usr/bin/csup -L 2 -g -z -h ${SERVER} /etc/cvsup/stable-supfile
        /usr/bin/csup -L 2 -g -z -h ${SERVER} /etc/cvsup/ports-supfile
        /usr/bin/csup -L 2 -g -z -h ${SERVER} /etc/cvsup/doc-supfile
    ;;
    esac    
fi

Set the right permissions:

chmod 700 /usr/local/sbin/runcvsup

Update everything:

runcvsup

How to “disable” the VLAN1 on a Cisco SLM 2048 switch

mariusvw — Sat, 27 Aug 2011 14:33:35 +0000

I have been busy with this but with a wrong way of thinking...

How you can disable it? Simple, leave it on VLAN1 and move all ports except one to another VLAN.

You can do this in the port configuration, set the ports to your own VLAN by changing the PVID (VLAN ID).

Ixy and her “What are you looking at!” look to the camera

mariusvw — Sat, 23 Jul 2011 14:52:00 +0000

It seems that Ixy likes seeing her self in the camera... She even doesn't get scared when I come with my hands near her. Normally she flies away even if you just point at her

PHP Performance – isset() versus empty() versus PHP Notices

mariusvw — Sun, 17 Jul 2011 14:01:14 +0000

I’m cleaning up a lot of PHP code and always program with PHP error_reporting set to E_ALL and display_errors turned on so that I make sure to catch any PHP messages that come up. Since starting on this site, I have fixed literally hundreds (maybe thousands) of PHP Notices about using uninitialized variables and non-existent array indexes.

I have been fixing problems like this where $somevar is sometimes undefined:

if ($somevar)

by changing it to:

if (isset($somevar) && $somevar)

This successfully gets rid of the NOTICEs, but adds some overhead because PHP has to perform two checks. After fixing a lot of this in this manner, I’ve noticed that the pages seem to be generated a little slower.

So, to provide some conclusive results to myself, I wrote up a quick benchmarking script - available at php_empty_benchmark.php. It goes through 1,000,000 tests using each of these methods:

if ($a) - This generates a notice if $a is not set
if (isset($a)) - A simple clean way to check if the variable is set (note that it is not equivalent to the one above)
if (isset($a) && ($a) - The one that I have been using which is equivalent to if($a), but doesn’t generate a notice.
if (!empty($a)) - This is functionally equivalent to if($a), but doesn’t generate a notice.

It measures the time to perform 1 million tests using a defined percentage of values that are set. It then computes the difference as a percentage of the time taken for the original test (the one that generates the notices). A ‘diff’ of 100 means that the execution time is the same, greater than 100 means that it is faster, and less than 100 means that it is slower. A typical test produced these results:

With NOTICE: 0.19779300689697
With isset:  0.19768500328064 / Diff: 100.05463419811
With both:   0.21704912185669 / Diff: 91.128222590815
With !empty: 0.19779801368713 / Diff: 99.997468735875

In summary, using the if (isset($a) && $a) syntax is about 8-10% slower than generating the PHP Notice. Using !empty() should be a drop-in replacement that doesn’t generate the notice and has virtually no performance impact. Using ifset() also has no performance impact, but is not exactly the same as ‘if($a)’ since isset() will return true if the variable is set to a false value. I included it here, because it often make the code a little more readable than the !empty($a) syntax. For example:

$myvalue = !empty($_REQUEST['myvalue']) ? $_REQUEST['myvalue'] : '';

Versus

$myvalue = isset($_REQUEST['myvalue']) ? $_REQUEST['myvalue'] : '';

Source:
http://www.brandonchecketts.com/archives/php-performance-isset-versus-empty-versus-php-notices

How to download sexdumpert.nl photo’s or video’s with a simple Bash script

mariusvw — Sun, 17 Jul 2011 13:38:53 +0000

Here is the simple script which downloads all photos from sexdumpert.nl

Just save the file as run.sh in a directory and run it. It will save all photos found.

#!/bin/bash
 
if [ ! -d 'files' ]
then
    mkdir files
fi
 
for ((a = 0; a <= 999; a++))
do
    ca=`printf "%03d" $a`
    for ((b = 0; b <= 999; b++))
    do
        cb=`printf "%03d" $b`
        for ((c = 0; c <= 999; c++))
        do      
            cc=`printf "%03d" $c`
            for ((d = 0; d <= 999; d++))
            do      
                cd=`printf "%03d" $d`
 
                url="http://mediadata.sexdumpert.nl/$ca/$cb/$cc/$cd.jpg"
                echo $url
                /usr/bin/curl $url -o "files/$ca-$cb-$cc-$cd.flv"
 
            done    
        done    
    done    
done

Here is the simple script which downloads all video's from sexdumpert.nl

Just save the file as run.sh in a directory and run it. It will save all video's found.

#!/bin/bash
 
if [ ! -d 'files' ]
then
    mkdir files
fi
 
for ((a = 0; a <= 999; a++))
do
    ca=`printf "%03d" $a`
    for ((b = 0; b <= 999; b++))
    do
        cb=`printf "%03d" $b`
        for ((c = 0; c <= 999; c++))
        do      
            cc=`printf "%03d" $c`
            for ((d = 0; d <= 999; d++))
            do      
                cd=`printf "%03d" $d`
 
                url="http://mediadata.sexdumpert.nl/$ca/$cb/$cc/$cd.flv"
                echo $url
                /usr/bin/curl $url -o "files/$ca-$cb-$cc-$cd.flv"
 
            done    
        done    
    done    
done

Hope this for fills some people their needs

How to check if a key exists in an array with in_array for Bash

mariusvw — Sun, 17 Jul 2011 13:34:16 +0000

When working with Bash it might become handy to have a way to check if a record exists in an array. In PHP you have in_array for this... The below code adds a function similar to the PHP variant.

function in_array() {
  local x
  ENTRY=$1
  shift 1
  ARRAY=( "$@" )
  [ -z "${ARRAY}" ] && return 1
  [ -z "${ENTRY}" ] && return 1
  for x in ${ARRAY[@]}; do
    [ "${x}" == "${ENTRY}" ] && return 0
  done
  return 1
}
 
MASTER=()
CURRENT=()
FIRST=1
for SERVER in ${SERVERS}; do
  # collect all builds from server and populate CURRENT list
  COMMAND="${LS} -1fd ${WEBROOT}/${SITE}.*"
  BUILDS=`${SSH} ${SSHOPTS} root@${SERVER} "${COMMAND}"`
  for BUILD in ${BUILDS}; do
    CURRENT=( ${CURRENT[@]-} ${BUILD} )
  done
 
  # if this is our first time around, copy CURRENT to MASTER
  if [ ${FIRST} -eq 1 ]; then
    MASTER=( ${CURRENT[@]} )
    FIRST=0
  fi
 
  # now we do a compare between MASTER and CURRENT to see what builds
  # are common
  INTERSECT=()
  for ENTRY in ${CURRENT[@]}; do
    in_array "${ENTRY}" "${MASTER[@]}"
    RET=$?
    if [ "${RET}" -eq 0 ]; then
      INTERSECT=( ${INTERSECT[@]-} ${ENTRY} )
    fi
  done
  MASTER=( ${INTERSECT[@]} )
 
  # clear the CURRENT array
  CURRENT=()
done

Source: http://mykospark.net/tag/in_array/

How to add Base64 encoding and decoding in C

mariusvw — Sun, 17 Jul 2011 09:36:53 +0000

I found this page on the web while searching for something else but I thought this might be useful to others

Overview
libb64 is a library of ANSI C routines for fast encoding/decoding data into and from a base64-encoded format. C++ wrappers are included, as well as the source code for standalone encoding and decoding executables.

Base64 uses a subset of displayable ASCII characters, and is therefore a useful encoding for storing binary data in a text file, such as XML, or sending binary data over text-only email.

Usage

#include 
#include 
int main() {
	base64::encoder E;
	E.encode(std::cin, std::cout);
	return 0;
}

You can read more info and download the package on the url below:

http://libb64.sourceforge.net/

Convert pipe diameters from Inches, DN (Diametre Nominal) and mm (Millimeter)

mariusvw — Thu, 14 Jul 2011 11:35:47 +0000

Pipe is made of a wide variety of materials - like galvanized steel, black steel, copper, cast iron, concrete, and various plastics such as ABS, PVC, CPVC, polyethylene, polybutylene and more.

Pipes are identified by "nominal" or "trade" names that are loosely related to the actual dimensions. For instance, a 2-inch galvanized steel pipe has an inside diameter of about 2 1/8 inches and an outside diameter of about 2 5/8 inches.

In plumbing pipe size is referred to as nominal pipe size - NPS, or "Nominal Pipe Size". The metric equivalent is called DN or "diametre nominel". The metric designations conform to International Standards Organization (ISO) usage and apply to all plumbing, natural gas, heating oil, and miscellaneous piping used in buildings. The use of NPS does not conform to American Standard pipe designations where the term NPS means "National Pipe Thread Straight".

Convert the pipe diameters with the inner and outer diameter in millimeters, the inner surface and wall thickness.

How to grab the mouse position in a browser with jQuery and HTML5

mariusvw — Thu, 14 Jul 2011 08:15:52 +0000

Depending on what your plans are it might become handy to know the mouse position.
The script below gives you the position relative to the page, relative to the browser window and relative to the DIV with the green color.

HTML (index.html)




    
    
    


    
    Page: 
    Client: 
    Container:

CSS (style.css)

* {
    margin: 0px;
    border: 0px;
    padding: 0px;
}
#object {
    width: 595px;
    height: 842px;
    margin: 10px;
    background: #cfc;
    border: 1px solid #666;
    float: left;
}
.info {
    padding-top: 100px;
}

JavaScript (javascript.js)

$(function() {
    $("#object").mousemove(function(e) {
        var pageCoords = "( " + e.pageX + ", " + e.pageY + " )";
        var clientCoords = "( " + e.clientX + ", " + e.clientY + " )";
        var cLeft = e.pageX - $(this).offset().left;
        var cTop = e.pageX - $(this).offset().top;
        var containerCoords = "( " + cLeft + ", " + cTop + " )";
        $("#page span").text("( e.pageX, e.pageY ) - " + pageCoords);
        $("#client span").text("( e.clientX, e.clientY ) - " + clientCoords);
        $("#container span").text("( e.clientX, e.clientY ) - " + containerCoords);
    }).click(function(e) {
        var x = e.pageX - this.offsetLeft;
        var y = e.pageY - this.offsetTop;
        var containerCoords = "( " + x + ", " + y + " )";
        alert("You clicked: ( e.clientX, e.clientY ) - " + containerCoords);
    });
});