Ad:

C Discussion Thread
Unsolved
Views: 523

May 9th, 2009

Keep a number as a byte?

Expand Post »

Hello.
I'm developing a encryption program. I'm testing with encryption right now.
I use bitwise operators and also bitwise shifts. [OR [|], XOR[^], AND[&], NOT[~], right[>>],left[<<]]

To add even more security, I went ahead and added bitwise shifts.
Whenever I shift the numbers, they go over 256 [max int in a byte].
Is there any way I can declare the integer so that it doesn't go above 256, and if it does it just overlaps?

I'm sorry I can't explain it well, I know C very little..

Similar Threads

converting a text or xml file into binary format in Visual Basic 4 / 5 / 6
memory management in wndows 2000 in Windows NT / 2000 / XP
creating byte stream in C
ASCII to number. I need a brilliant mind. in Assembly
Operation on Binary number, Need source code for elementar operation (+-*/) in C

Petrock6

Reputation Points: 10

Solved Threads: 1

Newbie Poster

Offline

9 posts
since Mar 2008

Permalink

May 9th, 2009

Re: Keep a number as a byte?

No. You'll have to write a cyclic shift macros or function. ie, something like
[code]#define cyclicShiftRight(val,shiftBy) ...code here...

C Syntax (Toggle Plain Text)
#define cyclicShiftLeft(val,shiftBy) ...code here...
//...
char num = 0x80; //1000-0000
cyclicShiftRight/Left(num,3); //0000-0100
#define cyclicShiftLeft(val,shiftBy) ...code here...
//...
char num = 0x80; //1000-0000
cyclicShiftRight/Left(num,3); //0000-0100

Last edited by twomers; May 9th, 2009 at 5:35 pm.

twomers

Reputation Points: 453

Solved Threads: 57

Posting Virtuoso

Offline

1,873 posts
since May 2007

Permalink

May 10th, 2009

Re: Keep a number as a byte?

That's going to be a pain in the rear end -.-..
Thanks.

Petrock6

Reputation Points: 10

Solved Threads: 1

Newbie Poster

Offline

9 posts
since Mar 2008

Permalink

May 10th, 2009

Re: Keep a number as a byte?

You can store it in a char (8 bit) variable.
Even if "char" gives impression of "character" variable actually it's just a integer of 8 bits.

This should solve you problem if I got it correctly. Otherwise please clarify your problem.

NeoKyrgyz

Reputation Points: 48

Solved Threads: 1

Light Poster

Offline

38 posts
since Jan 2009

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.

Previous Thread in C Forum Timeline: A little help with times and structures.

Next Thread in C Forum Timeline: create output files

DaniWeb Message

Cancel Changes

User Name
Password