Implemented cksum

[cospplredman]

cksum is one of the posix utilities of all time.

[Sigmanificient]

Please remove the binary file and add it to gitignore list.
Make sure to add your the folder name in BINS variable of the global Makefile

[Sigmanificient]

Can you run clang-format? This enforce coding style consistency across all sources

[Sigmanificient]

The core logic is a bit cryptic (mostly bit manipulation) so I couldn't tell what happening there
Hopefully you can provide some screenshot to show that this is working properly

[proh14]

hello @cospplredman. thanks for your pr. please test this before we merge it. Also, be sure to provide. if you tasted all the edge cases, mention me so I can merge it. ;)

[cospplredman]

My testing methodology is as follows: run both my implementation and the gnu implementation on every file in the cksum directory.

$ ./cksum *
175369053 16296 cksum
1855786587 7 cksum.1
4088649404 2179 cksum.c
1192622583 51 Makefile
197436690 157 test.sh
$ cksum *
175369053 16296 cksum
1855786587 7 cksum.1
4088649404 2179 cksum.c
1192622583 51 Makefile
197436690 157 test.sh

the results match as far as i can tell.

One notable difference between this implementation and the gnu implementation is that I do not handle directories, I opt to instead just return EXIT_FAILURE. The reason I prefer to fail is that there isn't a standard C way of checking if something is a directory, so any method of doing so would break me from my (very tasteful) c99 compliance, and cksum is only defined on files anyways.

[proh14]

do you handle flags?

[proh14]

also pull the latest changes

[proh14]

thx ;)