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After my last post about Android, I want to highlight some of the best things about the modding community. Thanks to the Google Android Open Source Project, projects like Cyanogenmod provide for an alternative operating system image for many Android devices. In the case of the AT&T Captivate, the latest official OS is Android 2.3 Gingerbread. A "stable" CM7 exists that is also based on Android 2.3; however, a more recent build exists, CM version 9, based on the latest Android 4 (Ice Cream Sandwich, or ICS). When I upgraded from stock Samsung OS to CM7, the functionality of my device was far better than the original OS. Upgrading CM7 to CM9 was even a bigger upgrade, like night and day, and despite being labeled an "experimental" build, it's been far more stable than CM7. With the Samsung OS I would lose wifi and cell all the time, on CM7 I did not but the phone would lock up and I had to reboot it. Since CM9 I have had no problems at all.

Open platforms require respect. Open platforms provide freedom and with freedom comes the responsibility to not abuse that power. When that power is abused, respect is lost and then instead of a innovative collaboration between OEM and community, it becomes more like a battle, as with iOS. Do we really want to encourage OEMs to take Android down the path of locked down OS builds, underground modding, paying for the privilege just to make an app subject to arbitrary rules and delays from a app store resulting from a forced monopoly?

I believe that a few recent posts by xda-developers and Engadget crossed that line of respect. Recently, a leaked firmware for the new Samsung Galaxy S3 became available online. Shortly after, an XDA user ripped all of the proprietary apps off the image, including S-Voice, a direct competetor to Apple's Siri, and posted them in a thread called S-Voice and ALL I9300 goodies (Get whatever you want). This was then highlighted as front page news "Samsung S Voice Ripped for the World to Enjoy", and covered on Engadget. Samsung then blocks clients not on S3 with a simple check of the phone's model name, something trivial to workaround technically but a clear sign (in my opinion) that Samsung did not want this happening. Shortly afterwards, a cracked copy surfaces that sends S3's model code regardless where it is installed, "fixing" the issue. XDA praises this achievement again on the front page as S Voice Back Again, the XDA Way. People rip apps/ROMs/proprietary functionality all the time, but some aspects of this particularly bothered me:

I have been experimenting with GWT using a RESTful (jersey server) backend as its data source.  When deploying both my application and the backend to the same server this worked great, but once the server side was finished I wanted to deploy it to Tomcat on my Amazon EC2 instance, and continue debugging the application using GWT's Developer mode.  This, unfortunately, does not work, due to Same Origin Policy restrictions of virtually all browsers.

The most standard way of circumventing the Same Origin Policy is to use Json with Padding, or JSONP.  The technique in a nutshell is that the server returns a JavaScript function call.  The client thas prepared for this by creating this function in the DOM of the current page in the browser.  The client tells the server "The name of the function is xyzzy" by sending in a query parameter, usually named "callback." This post shows some ways around this issue.

A major bug in GNE put HawkNL properly in little endian mode when using NO_NET network type, but any other type such as NL_IP called nlInit after nlEnable(NL_LITTLE_ENDIAN_DATA), which erased this setting. Amazingly, over all these years this error was not caught. I very seriously thought about changing all documentation and having GNE use big endian all the time, but decided to fix the bug and use little endian consistently.

Thanks goes out to Héber Costa Ferreira for finding this problem in GNE/HawkNL and providing suggestions, code, and testing effort to fix this issue.

This change has been commited into GNE SVN as of revision 680. If you are not using the SVN version of GNE, you should, it is much more stable than 0.70 and contains many critical fixes.

This Friday, I will be giving a presentation on Groovy at the university where I work (RIT). You can view the presentation online (with extra notes under "speaker notes") or as a PDF and you can view or download the source code for the examples. It is primarily meant for audiences already familar with Java code, but it should be approachable if you know other languages like C#. A description of the talk:

Groovy is a dynamic language for the Java Virtual machine inspired by Python, Ruby, and Smalltalk. After Java, it is the first approved JVM language (via JSR 241). Groovy can be used as a scripting language in a shell environment, a way for applications to provide scripting and extension capabilities, domain specific languages and configuration files, or as the base language for whole applications and frameworks such as Grails (like Ruby on Rails) and Griffon. Due to supporting most Java syntax and ability to integrate with any existing JVM code, Groovy is particularly useful for existing Java developers wanting to leverage dynamic languages while retaining use of the full Java ecosystem.

This talk will cover the following areas:

• Groovy syntax compared with Java
• How dynamic calls are implemented
• Closures
• Runtime Metaprogramming: how Groovy extends existing Java libraries
• Compile-time Metaprogramming (AST transformations)
• Creation of Domain Specific Langauges (DSLs)
• Code examples where Groovy's features make the strongest impact 

I'm getting to play with the BeagleBone, an "embedded" ARM device. The "official" image for this device contains a build of the Angstrom distribution. Angstrom itself is based on OpenEmbedded. If you want to modify or make any software for the bone, or just stay on the cutting edge and build your own images, you want to build using the bitbake system (instructions are at the bottom of this page). Once you've gone this far, you might wonder if you can extend this to build your own software. Currently I'm trying to figure it out, but the documentation is very hard to find and I wanted to share the locations of the most useful information in the hope that this helps your search. Read on for more details.

I was placed in a situation of updating and redeploying a PHP application on an older IIS 6 server. I have some small experience with PHP, but none at all with IIS (only Apache). One thing that I feel is very important that I know not everyone cares about is having clean URLs, or at least, removing the extension of dynamic pages. I don't know why a user to a website should have to see and know (when typing) whether my page is implemented in PHP, ASP, ASPX, JSP, or whatever. Typically I also like to remove .html as well, but actually I feel you can go either way on that one (because HTML is the content type the browser sees, not a backend). In this case the site was already moving URLs, and the long-term move away from PHP was also possible. I didn't want to risk having to break bookmarks again in the future.

Normally in Apache I would turn on MultiViews and also rely on default files like index.htm/php. While IIS 6 supports default files, it doesn't support MultiViews as far as I can tell. My searching didn't find much workarounds. I did find Ionic's Isapi Rewrite Filter though, which bascially is an open-source mod_rewrite for IIS. Read on for details on my configuration.

At work, I and the other software developers work primarily with the Java programming language. Part of our organization's goal involves algorithms and scientific data analysis of data sets, which is researched by another team. Traditionally there has been a lot of data analysis and scientific work with Matlab, but since the team has switched to Python. Python appears to have a strong scientific community and tools (such as pythonxy) for rapid development for scientific computing, data analysis, and data visualization. Since then, I have looked at ways where we can collaborate by running their algorithms in the JVM, without the need for costly and error-prone porting to Java. Ideally I'd like a way for the Python code to leverage a codebase developed over 8 years for our problem domain, and for Java code to leverage new work being done in Python.

Read on for my current progress...

Short answer for the web searchers: if /usr/bin/emacs points to jove, install emacs.

I've had the privilege of starting to play around with Angstrom (fork of OpenEmbedded) on the BeagleBone. I needed to build some bleeding-edge software with bitbake on an Ubuntu 10.10 but I ran into an interesting problem. When building the distribution, it builds all of the tools from the ground up, including automake. However, automake would crash when building some sort of support for emacs with a jove crash. I couldn't understand how they were related.

In the end, I found that since jove was installed but Emacs was not, /usr/bin/emacs actually pointed to starting jove. Automake was trying to use some kind of compiler for emacs (I guess it was making some emacs macros or syntax thing?). It must have thought emacs was properly installed and called Jove with a set of parameters that caused it to crash. In the end, the solution was to install Emacs. The build system itself wasn't in error, it was my machine, so it can't be reasonably "fixed" in the code so I put this post in hopes of people finding it if they search for the same problem.

At work I've been making a foray into web development. I've always been one to be very interested in "how to do it right" rather than just "get it done" and stop when it looks like it works. Security is one of the things where it works perfectly for the user -- but also for the attacker if you don't do it right. I've had a lot of experience with securing things with encryption, but the web is an entirely new (and scary) world.

The two attack vectors I looked into is XSS (Cross-site scripting) and CSRF (cross-site request forgery, aka XSRF).