Tweet Remarks

ioccc 2011

NOTE: This no longer works due to changes in API. It did work at time of submission.

To Make

make all

To Run

tweet <username>

Examples:

tweet ioccc
tweet slashdot

WARNING

Be careful not to disrupt the long string at the end of the file when reformatting the code. Some formatting tools alter the whitespace in the string. The program will not work if the whitespace in the string is altered.

About

This program reads the timeline for the given user then scrolls the timeline vertically in the terminal. When it is finished scrolling all the messages in the timeline it will re-request the timeline and display it again. If the program has finished outputting all of the messages and 60 seconds have not elapsed it will simply repeat the messages from its previous request without making a new request.

To terminate the program type ctrl-c or send it the TERM signal. The program has registered signal handlers for both SIGINT and SIGTERM.

This program properly allocates and frees memory. It handles most error conditions. When the program detects an error it exits by returning from all functions. The program's return value corresponds to the line in the source file where the error occurred.

I have compiled this program with -Wall and -ansi on 32 and 64 bit Linux, HPUX and PPC Mac OS X. It compiles warning free. Who says you can't write good obfuscated code?

Source Code

Best viewed with 81 columns and tabs set to display as one space. Tabs are not used in formatting the code but there is a rather lengthy string that contains tabs and fits nicely in 81 columns when the tabs are displayed as a single space.

Bending the Rules

You might notice that my program file is 4086 bytes. It seems awfully close to the limit. It is. I don't think 4086 bytes is bending the rules and it certainly isn't breaking the rules...

At the end of the file you will see a string that contains 1600 characters of whitespace. If you look closely you'll notice that the string contains both space and tab characters. Since non-whitespace characters (with some exceptions) are limited to 2048, I couldn't burn a bunch of characters to create my vertical extra-large character map. Even after excluding all ASCII characters above 0x5f from the character map I was still consuming far too many bytes. Then it occurred to me: why not create the character map using whitespace?

I don't think a 1600 byte string of whitespace conforms to the spirit of the rules but the rules certainly don't disallow it.

Obfuscation

Mostly I copied the style of code I see at work on a daily basis. The techniques I've learned at work have adequately prepared me for this contest.

• I employed a lot of inconsistency in my obfuscation. I have found that some of the most difficult to understand code is simply inconsistent in every way.

• Function pointers. Without them we couldn't do wonderful things like callbacks and faux polymorphism. Why in the world would anyone use them the way I have here? Only to obfuscate the code a little more.

• K & R style function declaration. But only once. Sure the old guys don't think twice about this notation but run it by a newb and he'd think you've gone mad. RIP Dennis Ritchie.

• Variable shadowing. Isn't scope fun?

• Variable re-use. Nowadays most compilers are going to optimize in ways that you'd spend way too much time looking for. There aren't many good reasons to re-use variables. You're just asking to shoot yourself in the foot.

• Non-descriptive variable names. This isn't amazing but what is amazing is how programmers seem to think that 1 character names are totally fine when they know full well they'll be turning their code over to someone else to maintain.

• Use of #defines. Nothing noteworthy about this. It's just frustrating to read and maintain. I don't personally have anything against pre-processor macros, it's just that almost every macro I've seen in my life was made for all the wrong reasons and served almost no purpose except to obfuscate the code that would otherwise be easy to understand.

• Formatting. The easiest way to make everyone's life miserable.

• Various other things hardly worth mentioning: anonymous struct, escaped characters, split strings, magic numbers, gotos and stuff I've probably forgotten.

• I didn't use trigraphs. They seem boring.

• I didn't use -D compiler directives. I wanted all the pieces to be visible in a single file.