The Open Source U

As some readers will know, I’ve been working to study the architecture of FireFox. One thing I realize is that I’m not as familiar as I should be with some of the common open source tools, or what I consider to be the common open source tools.

Below is a list of tools that are worth learning (in my opinion). I’ve also included a short description of why it might be worth learning them. (The list is in no particular order)

If you have an interest in open source, it will not hurt to get a quick base understanding of each of these. I’m not saying you (nor am I trying to) become an expert in each of these tools. However, having a basic understanding of syntax and function should save time and headache while trying to understand a project.

1. Linux: The concepts in and around Linux are often used on other open source products. I think Open Source developers tend to stick with using open source software. So, there is a link there.
2. Bash: The de-facto standard shell for Linux (as far as I can tell). Knowing the basic usage of bash can save you time and confusion.  Certain scripts can depend on feature of your terminal interface. The Mac OS X ships with a version of bash, which is good to know…
3. GCC: This is the GNU Compiler Collection and is often a requirement to build open source packages.
4. Make: This is a part of the GCC but I want to make special mention of this because knowing how to read the script files and error messages can help diagnose an error.
5. C / C++: Low Level libraries are often written in C or C++, even for an otherwise Java or Python based program.
6. Python: Python is sometimes used in conjunction with Make to check for build dependencies, verify (build) requirements, or many other possible things.
7. Perl: Often used like Python, from what I understand but I’ve yet to learn much about it.
8. Subversion: This is the most common open source VCS software in use (based on my own observations)
9. Mercurial: One of the two popular DVCS systems. I’ve noticed more and more open source projects switching to DVCSs, so a basic working knowledge of Mercurial and Git is helpful.
10. git: The second of the two popular DVCS systems.

If you’d like to contribute to the list, please leave a comment below but please ensure you include a fair reason.

This is a follow up post to a series I’ve been posting. The previous post to this posting was “Firefox – Found time to Try again!”

I finally was able to get Firefox to build on my Vista machine. It has given me a lot of trouble and I’ve had to troubleshoot several times. Relative to my previous post, I was last held up on a “NSInstall” error. NSinstall.exe would report “Bad File Number”.

The solution was reducing the directory depth. I had my mercurial repository in a sub folder of my documents folder. Specifically C:\Users\Frank\Documents\hg-repos\mozilla-fv-expirement\. I moved the directory to C:\mozilla-fv-expirement\ and re-ran the build script. It did it’s thing and I was able to fire up good-’ol firefox.exe from the [...]\dist\bin folder. I even checked my gmail account on it.

Now where?

I felt that before I started hacking and understanding the source code, I should be able to build the program. That way, if I make a significant change I can see how the code base reacts to it. Though, my intentions are not to hack but to understand how it works. The ability to drop print statements in should help with this… maybe…

Additionally, I hope to contribute to the Mozilla Litmus QA system. I might as well — I did take the time to build the trunk.

My attempts to build Firefox on windows continue today. If you recall , previously, I’ve had great success with Mac OS X which I tried by chance but I’ve had problems while attempting the same thing on Windows.

This experience has made me decided that my troubles with building open source program in the past has stemmed from my usage of non-unix based operating systems — Windows — and my lack of understand about make, autoconf, python and perl.

Ok, lets go….

I’ve updated to the latest tip of Mozilla Central and at this very moment, I’m at revision 80f4cdc242b9. I expect to be working with this revision throughout the remainder of this post. Though, in general the exact revision shouldn’t matter if you are attempting the same thing.

I’ve just tried to build with the command make -f client.mk

I’ve received an error and while writing this I just thought of why. It’s stupid reason but one is bound to make mistakes like this. Simply put, I forgot the very required mozconfig file. I cloned my “clean” repository to a new directory to start over and I forgot this file. For records (and search engines) the exact error I received was “configure: error: –enable-application=APP was not specified and is required.”

So, now lets actually follow the directions since we are not experts.

I’ve reread the MDC about building Firefox and I’ve created a .mozconfig files. I’ll put it below for my and your reference. Don’t assume you should use this — check out the Mozilla docs. They are very straight forward.

# My first mozilla config - https://developer.mozilla.org/en/Configuring_Build_Options

mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/obj-@CONFIG_GUESS@

ac_add_options --enable-application=browser
mk_add_options MOZ_CO_PROJECT=browser

# Use the follow two for debugging (if desired)
# ac_add_options --enable-debug    
# ac_add_options --enable-tests

The # is the comment indicator and as you can see, I’ve setup but not enabled my options for debugging. I hope to use these later but for now I’ve decided to disable them.

Given the above .mozconfig file, I’ve attempted to rebuild and run in to an apparent known issue with building on Vista. Mozilla has done a beautiful job document the reason and how to fix it.The exact error is: “configure: error: System header oleacc.idl is not available” but right afterward the URL is given.

To correct this problem, Mozilla has listed three options. I’ve elected to attempt the “Use Windows 2008 SDK” option. I wasn’t sure which to pick but I decided that the 2008 SDK seems to be supported as the site states “Unfortunately, the Vista or Windows 2008 SDKs are required to build Mozilla”. I wish the page made a recommendation or gave pros and cons but perhaps it doesn’t matter…

The next error

After getting the Windows 2008 SDK installed and up to date, I received another error. This time the error read “nsinstall: Bad file number”. I’m not sure where to go from here, so I posted at the usenet.

The prevalent solution was to run as administrator, according to these two articles:

• Penelope Developer Page
• kevin brosnan dot net

This hasn’t worked for me; I’m still trying to figure this out. Apparently, my success is not going to come today so I’m setting this aside for the time being.

In the hopes of continuing soon, I’ve posted two questions:

• Usenet
• Stack Overflow