Thushan Fernando Uncut

From The IT Crowd Season 4 Episode 5 -- Bad Boys.

I spent some time tweaking my blog today after moving it to some fresh hardware. You may find that everything is loading much faster now which can be attributed to two plugins in addition to the hardware upgrade – wp-super-cache and wp-widget-cache.

I’ve also fixed a long standing bug with my particular configuration of WordPress that runs on IIS which causes the “Older posts” link at the bottom does not function for the second page. The WordPress generated URL for this is

Which is a bit problematic, this ofcourse can be reproduced only on IIS from my musings (serves me right eh?). There are a couple of suggestions by people on the forums already, but I wasn’t too keen on them as they seemed too high-level fixes.

I’ve enabled Permalinks with this format:

So I looked through the sources to see why this was happening. After a bit of snooping about I got to the get_pagenum_link function in wp-includes/link-template.php file.

Heres a bit of source for reference – this is with WordPress 2.9.2:

function get_pagenum_link($pagenum = 1) {
	global $wp_rewrite;

	$pagenum = (int) $pagenum;

	$request = remove_query_arg( 'paged' );

	$home_root = parse_url(get_option('home'));
	$home_root = ( isset($home_root['path']) ) ? $home_root['path'] : '';
	$home_root = preg_quote( trailingslashit( $home_root ), '|' );

	$request = preg_replace('|^'. $home_root . '|', '', $request);
	$request = preg_replace('|^/+|', '', $request);

	if ( !$wp_rewrite->using_permalinks() || is_admin() ) {
		$base = trailingslashit( get_bloginfo( 'home' ) );

		if ( $pagenum > 1 ) {
			$result = add_query_arg( 'paged', $pagenum, $base . $request );
		} else {
			$result = $base . $request;
		}
	} else {
		$qs_regex = '|\?.*?$|';
		preg_match( $qs_regex, $request, $qs_match );

		if ( !empty( $qs_match[0] ) ) {
			$query_string = $qs_match[0];
			$request = preg_replace( $qs_regex, '', $request );
		} else {
			$query_string = '';
		}

		$request = preg_replace( '|page/\d+/?$|', '', $request);
		$request = preg_replace( '|^index\.php|', '', $request);
		$request = ltrim($request, '/');

		$base = trailingslashit( get_bloginfo( 'url' ) );

	if ( $wp_rewrite->using_index_permalinks() && ( $pagenum > 1 || '' != $request ) )
		$base .= 'index.php/';

		if ( $pagenum > 1 ) {
			$request = ( ( !empty( $request ) ) ? trailingslashit( $request ) : $request ) . user_trailingslashit( 'page/' . $pagenum, 'paged' );
		}

		$result = $base . $request . $query_string;
	}

	$result = apply_filters('get_pagenum_link', $result);

	return $result;
}

This function (from reading through) essentially generates the links for the page numbers & page navigation taking into account Permalinks if configured. This is all fine and dandy for Unix hosts but for Windows, unfortunately this bit of code fails us.

...
$request = preg_replace( '|page/\d+/?$|', '', $request);
$request = preg_replace( '|^index\.php|', '', $request);
$request = ltrim($request, '/');
...

As the preg_replace is case sensitive, it will not replace the invalid Index.php that is seen on IIS. So the easiest fix is to tweak the regex pattern a little bit and tell it be case insensitive.

...
$request = preg_replace( '|page/\d+/?$|', '', $request);
$request = preg_replace( '/|^index\.php|/i', '', $request);
$request = ltrim($request, '/');
...

This will then generate the (invalid) urls and the preg_replace will remove any additional Index.php’s from the request URL as its already mentioned in the $base variable a few lines below:

...
if ( $wp_rewrite->using_index_permalinks() && ( $pagenum > 1 || '' != $request ) )
$base .= 'index.php/';
...

Once you make the change and upload the files, your “Older posts” will start working again. I’ll submit a patch to WordPress I’ve submitted a patch to WordPress Trac, now its just a wait and see what they say, in the meantime here’s a patch file if you don’t want to modify sources manually. If there any issues, post a comment

What a way to start the weekend, jQuery 1.4 has been released! There’s so much ubber goodness in this release I nearly fell of my chair! I have yet to muse about but most definately worth a look, the performance boosts are insane!

I’ve been porting a few products to .NET 4.0 and came across some cool new additions in .NET 4.0 which will be quite useful for developers.

Strings

• String.IsNullOrWhiteSpace
  Like the String.IsNullOrEmpty method, this new helper method will check whether the string is null, empty or contains only whitespace characters (from Char.IsWhiteSpace)
• StringBuilder.Clear()
  Clear a StringBuilder contents instead of (the currently) setting of length = 0.
• String.Join (string, params[])
  Now you can easily join multiple strings without having to use an array.

  String.Join("one","two","three","four","uno","dos","tres", "quatro");
  

Streams

Remember writing this before to copy one stream to another?

public static void CopyTo(this Stream input, Stream output)
{
byte[] buffer = new byte[2048];
while (true)
{
int read = input.Read (buffer, 0, buffer.Length);
if (read <= 0)
return;
output.Write (buffer, 0, read);
}
}

Now you don’t need to, just use the Stream.CopyTo() method.

inputStream.CopyTo(output);

Checking for 64bit-ness

Previously to detect a 64bit operating system you would either P/Invoke out and call the IsWow64Process in Kernel32, looked at the “PROCESSOR_ARCHITECTURE” environment variable or even easier (and completely managed code) way of checking the size of a Pointer.

public static bool IsWin64
{
return (IntPtr.Size == 8);
}
public static bool IsWin32
{
return (IntPtr.Size == 4);
}

Now you can simply use the Environment class that comes with two new properties.

• Environment.Is64BitOperatingSystem() – Are we running on a 64bit operating system?
• Environment.Is64BitProcess() – Are we running as a 64bit process?

WPF 4.0 Improvements

There are simply too many to list, see the article on ScottGu‘s blog about WPF4 and VS2010/.NET 4.0.

One very important tweak are the Text Rendering improvements that TextBlock‘s now have a new TextOptions.TextFormattingMode that greatly improves the quality of text rendering.

<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid>
<StackPanel xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'
xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
<TextBox TextOptions.TextFormattingMode="Ideal" FontSize="11">ThushanFernando.com - Ideal</TextBox>
<TextBox TextOptions.TextFormattingMode="Display" FontSize="11">ThushanFernando.com - Display</TextBox>
<TextBox TextOptions.TextFormattingMode="Ideal" FontSize="16">ThushanFernando.com - Ideal</TextBox>
<TextBox TextOptions.TextFormattingMode="Display" FontSize="16">ThushanFernando.com - Display</TextBox>
</StackPanel>
</Grid>
</Window>

Here’s a pretty picture showing the difference between using Ideal and Display. The difference is noticable for text sizes below 15.

Alternatively you can place it in the Window so all child controls will render nicely.

<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow - Display" Height="350" Width="525"
TextOptions.TextFormattingMode="Display">
<Grid>
<StackPanel xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'
xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
<TextBox FontSize="11">ThushanFernando.com</TextBox>
<TextBox FontSize="16">ThushanFernando.com</TextBox>
</StackPanel>
</Grid>
</Window>

There are LOTS more coming in .NET 4.0 that will make anyone doing .NET development today just wet their pants over, just read the article on MSDN by Justin Van Patten about Whats new in the BCL in .NET 4.0 and also posted on the BCL team blog.

Apple Propaganda, I mean PR

I posted about Microsoft’s four new Windows 7 commercials the other day and yes, they *are* commercials -- they tell you a bit about the product they’re advertising. Now let’s take a look at Apple’s attempts -- great PR btw! I think they were going for: ‘lets create the most douchebaggy thing to publicise our product and have people post blogs about it’. Well here’s some free PR work courtesy of Apple.

Bill Gates may go down in history for the BSoD for Windows 98 but lest we forget that little kid in school who was always jumping up and down for attention, teasing the smarter kids because he just wasn’t getting any attention.

“Now what is this? I dunno, but it works.” -- Steve Jobs

“It’s pretty awesome when it works.” -- Steve Jobs

It sure is Steve, it suuuuure is. Think Different. It just works. I wonder how they’ll cover having an ad-supported Mac OS X operating system in the future?

Linus Torvalds

Anyway I much prefer the suttle attitude that Linus Torvalds took at the Japan Linux Symposium.

He’s got a sense of humour (and coolness) and as a Linux user (#412328) I’m ever grateful for his operating system. Damn I miss Japan

Here’s four new Microsoft Windows 7 commercials, 7 seconds to talk about Windows 7.  Short, sweet functionality and to the point. Oh  and look, they don’t seem to need to be bashing their competitors (awww!).

Having used Windows 7 now for close to 2 months I have to say its nothing but pure awesomeness. If you have MSDN there’s no excuse not to try it out. I’ve been too busy to even blog about it

Microsoft has just released VisualStudio 2010 Beta 2 to MSDN Subscribers – aka Rosario.

I’m not sure why they’re going with the ULTIMATE moniker for Visual Studio, I still prefer the VS6 style Standard, Professional, Enterprise. Meh.

• Microsoft Visual Studio 2010 Ultimate with MSDN
  The comprehensive suite of application lifecycle management tools for software teams to ensure quality results from design to deployment.
• Microsoft Visual Studio 2010 Premium with MSDN
  A complete toolset for developers to deliver scalable, high quality applications.
• Microsoft Visual Studio 2010 Professional with MSDN
  The essential tool for professional development tasks to assist developers in implementing their ideas easily. (Note: Visual Studio 2010 Professional will also be available without MSDN subscription)

Some of the more exciting things that are coming with Visual Studio 2010 are documented on MSDN or a better one would be Vikas Goyal’s post and also his .NET 4.0 coverage.. Personally the Parallel extensions are the most exciting bits for me. The new Java 7 work is concentrating heavily on concurrency and its good to see both camps pushing the boundaries.

I recently took a look at the ANTS Memory Profiler 5.1 from RedGate software and posted my thoughts on it at the DeveloperFusion market place. Having toyed with several profilers in the past – DevPartner from Compuware (who’s now someone else who now owns the product) being my primary love since I first came across their .NET version wayyy back in 2002 when I was writing for Australian Developer – see ‘ASP .NET and the Web: Optimising Application Performance’ (who became International Developer who are now no longer around!).

If anyone’s serious about their software you ought to have atleast one profiler (ProfileSharp’s free!) with you to catch those nasty leaks and ANTS MP seems to be the best of the bunch right now. While your at it, take a look at NDepend to add to your arsenal.

I love the fact that I can take a few snapshots, go to the Class list and filter by ‘Disposed objects which are still in memory’ and get a quick list, then drill in to find the sources. Give it ago.

Excited about Windows 7 launch to the public in October? Organise a party and get some swagger!

Choose a day from October 22-29 and if you’re selected, you’ll not only receive a special Signature Edition of Windows® 7 Ultimate but your very own Windows® 7 Party Pack.

Countries allowed to partaye!

• Australia
• Canada
• France
• Germany
• HongKong
• India
• Italy
• Japan
• Mexico
• Spain
• UK
• USA

Get the details and lets get this party started. (Did I mention I don’t like Pink?)

I’ve been working heavily with Red Hat Enterprise Linux (and subsequently CentOS) the past few months (shh! dont tell my MSFT homey!) and one of the great things about CentOS and RHEL is that they both install using LVM – which is a helluvah lot easier when time passes and you realise your running out of space on a drive.

But today I had to recover some data from an LVM partition and copy over some bits to another partition without actually booting the CentOS install (it was bj0rked by yours truely!). What to do? Throw in a Ubuntu LiveCD (or another) and just mount the partitions

First thing we need to do is install LVM – remember we need to be sudo for these to work.

$ aptitude install lvm2

Then scan for any available physical volumes on any of the drives.

$ pvscan

Scan for any Volume Groups that may be present.

$ vgscan

Now activate any of the Volume Groups that it finds, running this makes the logical volumes known to the kernel.

$ vgchange –available y

Then let it scan for any Logical Volumes on any drives

$ lvscan

After running the logical volume scan it will show the path to the LVM mount path, for my boxen it gives something like this

ACTIVE            ‘/dev/LVM/Data‘ [5.26 TB] inherit

You simply mount the path specified and browse like normally

$ mount /dev/LVM/Data /mnt

Enjoy.