Monthly Archives: April 2010

Open Source

foss-sthlm second meetup

Within the network of people we call foss-sthlm, the time is closing in towards our second meetup. Or “Möte #2” as we so imaginatively call it (translates to “meeting #2”), to be held in the same great place as the first one, on May 19th 2010.

Our first gettogether was an astounding success and I don’t expect us to be able to repeat that massive attention and number of attendees this time. Things still look good and the number of attendees just reached 80 with exactly three weeks to go, so there’s still good time for more people to decide.

This time we’ve lined up 5 speakers and we’ve made an deliberate effort to not re-use any of the speakers from the first metting to make sure more people get the chance. Unfortunately, that means I won’t do any talk! 😉 Topics this time (for those lazy enough to not visit the link or if you for any reason think Swedish is hard to digest) include:

Smalltalk, FOSS legalities in Sweden, Cross platform Qt, Women in Open Source and FFmpeg.

I’m glad that we once again have sponsors that will let us use the room for free, provide sandwiches and coffee for the break without charge so that we can do this thing admission free once again. We learned from the first meeting that we need a little break in the middle.

If you’re in the area and still haven’t signed up, please go ahead. We’ll get a full afternoon with hardcore FOSS talks, followed by the rest of the evening at a pub talking FOSS with Stockholm’s FOSS hackers that matter.

Logotype Competition

We’re also throwing out different logo alternatives on the mailing list as a kind of competition and I guess we’ll just vote for a winning contribution at some point. My personal favorite so far is probably this version created by Tommy Nevtelen:

Tommy-Nevtelen-FOSS_STHLM

cURL and libcurl, Development

professional libcurl hackers look this way!

In my company, Haxx, we work as consultants and we do contract development for customers who pay for our skill, time and dedication. We help them develop stuff.Haxx

We’re a small company, with basically two full-time employees. Most of our working days, we are involved with a single customer each who pays for our full-time involvement during a number of months. This is all good and fine. We love our jobs and we love our customers. We’re in it for the fun.

Now, these days we can see that the economy is slowly but surely gaining ground again and is getting up to speed. We hear more and more requests for help and potential assignments are starting to pour in. That’s great and all. Except that we’re only two guys and can’t accept very many projects…

Recently we’ve experienced a noticeable increase in amount of requests for support and other development help that involves curl and libcurl. I am the originator and maintainer of curl, there’s really no surprise or wonder that these companies contact me and us about it. I’m always very happy to see that there are companies and persons who are willing to pay for support of open source and in many cases pay for extending and bug fixing libcurl and have those fixes going back to the mainline sources without complaints.

Since we fail to accept a lot of requests, I’m interested in finding you who are interested in helping out with such work. Are you interested in helping out customers with curl related problems? Customers often come to us when they’ve got stuck within something they can’t easily solve themselves and they turn to us as experts in general, and experts on curl and libcurl in particular. And we are.

Before you think this is a great idea and you send me an email introducing yourself and your greatness in this area, please be aware that I will require proof of your qualifications. Most preferably, that proof is at least one good patch posted to the libcurl mailing list and accepted into the mainline libcurl code, but I’m open to accepting slightly less ideal proofs as well if you can just motivate why you failed to provide the ideal ones. Of course you will also need to be able to communicate in English without problems. Your geographical location, gender, race, religion, skin-color and shoe size are completely uninteresting.

I’m looking for someone interested in contract development, not full-time employment. We still do these kinds of jobs on a case by case basis and there may be one every two days, one per week or sometimes even less frequently. I want to increase my network of people I know and trust can deliver quality code and services for this kind of projects.

Can you help us?

cURL and libcurl, Development, Network

curl and speced cookie order

I just posted this on the curl-library list, but I feel it suits to be mentioned here separately.

As I’ve mentioned before, I’m involved in the IETF http-state working group which is working to document how cookies are used in the wild today. The idea is to create a spec that new implementations can follow and that existing implementations can use to become more interoperable.

(If you’re interested in these matters, I can only urge you to join the http-state mailing list and participate in the discussions.)

The subject of how to order cookies in outgoing HTTP Cookie: headers have been much debated over the recent months and I’ve also blogged about it. Now, the issue has been closed and the decision went quite opposite to my standpoint and now the spec will say that while the servers SHOULD not rely on the order (yeah right, some obviously already do and with this specified like this even more will soon do the same) it will recommend clients to sort the cookies in a given way that is close to the way current Firefox does it[*].

This has the unfortunate side-effect that to become fully compatible with how the browsers do cookies, we will need to sort our cookies a bit more than what we just recently introduced. That in itself really isn’t very hard since once we introduced qsort() it is easy to sort on more/other keys.

The biggest problem we get with this, is that the sorting uses creation time of the cookies. libcurl and curl and others mostly use the Netscape cookie files to store cookies and keep state between invokes, and that file format doesn’t include creation time info! It is a simple text-based file format with TAB-separated columns and the last (7th) column is the cookie’s content.

In order to support the correct sorting between sessions, we need to invent a way to pass on the creation time. My thinking is that we do this in a way that allows older libcurls still understand the file but just not see/understand the creation time, while newer versions will be able to get it. This would be possible by extending the expires field (the 6th) as it is a numerical value that the existing code will parse as a number and it will stop at the first non-digit character. We could easily add a character separation and store the
creation time after. Like:

Old expire time:

2345678

New expire+creation time:

2345678/1234567

This format might even work with other readers of this file format if they do similar assumptions on the data, but the truth is that while we picked the format in the first place to be able to exchange cookies with a well known and well used browser, no current browser uses that format anymore. I assume there are still a bunch of other tools that do, like wget and friends.

Update: as my friend Micah Cowan explains: we can in fact use the order of the cookie file as “creation time” hint and use that as basis for sorting. Then we don’t need to modify the file format. We just need to make sure to store them in time-order… Internally we will need to keep a line number or something per cookie so that we can use that for sorting.

[*] – I believe it sorts on path length, domain length and time of creation, but as soon as the -06 draft goes online it will be easy to read the exact phrasing. The existing -05 draft exists at: http://tools.ietf.org/html/draft-ietf-httpstate-cookie-05