.NET on Andrew Walsh

State behavioral pattern to the rescue.

Mon, 17 Mar 2014 00:00:00 -0700

The Creeping Problem
#

I recently found myself developing a request-response style system, where the lifetime of a request could be interrupted at any moment. For most same process execution, like your average desktop application, this is a concern, but arises more often when dealing with multiple coordinated processes. My case ended up being the latter.

PCAP-NG reader for .NET.

Wed, 10 Apr 2013 00:00:00 -0700

Introduction & Scope
#

The PCAP-NG file format is used to store network captured data used by great programs like Wireshark. There are several API's available for both Linux and Windows but none that are ported to .NET. I decided to make one for my own use in building a network traffic replay agent.

Reading and writing large binary data in T-SQL and ADO.NET.

Wed, 03 Oct 2012 00:00:00 -0700

Introduction
#

In some cases, you may want to read/write binary data from/to your relational database. This can be a problem when the data set size exceeds the memory address size (eg. 32-bit processes) or the managed large object heap cannot load it all without throwing an OutOfMemoryException. In those cases, you will need to load the data into memory in chunks. Fortunately, the T-SQL syntax supports this operation.

IMAPI version 2 managed wrapper.

Tue, 18 Sep 2012 00:00:00 -0700

Introduction
#

Microsoft introduced native image mastering support in Vista, going forward. The library itself is not too complex but the latest version of the image mastering API (IMAPI) has some quirks. This is well documented by Eric Haddan in his article describing how to build an interop file and use it from .NET.

Licensing using XML digital signing.

Tue, 14 Aug 2012 00:00:00 -0700

Motivation
#

One of the main concerns in any licensing implementation is that authored license files are coming from the trusted authority (ie. your company) and not some third party. This can be accomplished in software by encrypting and decrypting the license with a single key, but symmetric key storage can be cumbersome and have added complexity.

POCO not transforming into a POCO proxy.

Mon, 07 Nov 2011 00:00:00 -0800

A POCO (Plain Old CLR Object) must be transformed into a POCO proxy
[MyNamespace.MyClass ->{System.Data.Entity.DynamicProxies.MyClass_0A943C2FC37D33304CEB497A9210C754E3F553B50315F8E6F0F7A6FAF43777F2}]{.Apple-style-span style=“font-size: x-small;”})
in order for features like lazy loading and change tracking to work.

MSDN has a great article that explains how to prepare a POCO to be transformed into a proxy. If you find that an object retrieved or attached to the context does not show itself in the DynamicProxies namespace (eg. MyNamespace.MyClass instead of ...DynamicProxies.MyClass), then you probably don't have a compliant class. You may have noticed this already when hovering your mouse cursor over an instance and seeing the runtime information on it.

The distilled points are that your POCO must:

Writing a TEDS (IEEE 1451.4) parser.

Wed, 17 Aug 2011 00:00:00 -0700

I was tasked recently with writing a parser for TEDS bit stream data. There is an IEEE published paper with an overview of the standard but it doesn't give any examples for implementation. I was finally able to find a paper that gave examples but still had trouble parsing the data. I finally realized there is not only 2 selector bits after the basic TEDS block but selector bits inside the standard template (2 in the case of template 25). Here are my main findings:
\

Reentrant lock acquires in CLR.

Fri, 29 Jul 2011 00:00:00 -0700

I always like when a post gets to the point (especially after searching in Google). In short, if you perform an operation that waits to acquire a lock, the thread doesn't actually stop.

In concrete terms of .NET coding, if you call the WaitOne method on a thread, it may still process events that the CLR deems "high priority". This can be a big problem if the event handlers go into the critical region you are trying to protect.
\

.NET on Andrew Walsh

State behavioral pattern to the rescue.

The Creeping Problem #

PCAP-NG reader for .NET.

Introduction & Scope #

Reading and writing large binary data in T-SQL and ADO.NET.

Introduction #

IMAPI version 2 managed wrapper.

Introduction #

Licensing using XML digital signing.

Motivation #

POCO not transforming into a POCO proxy.

Writing a TEDS (IEEE 1451.4) parser.

Reentrant lock acquires in CLR.

The Creeping Problem
#

Introduction & Scope
#

Introduction
#

Introduction
#

Motivation
#