Overflow detected! Banker script

[Feistz]

Got this error in a Bank script in my server. This error pops up whenever i choose to withdraw or deposit zeny. Can someone help me on this?

bank.txt

[plankt]

The error itself in english:

Warning. Overflow detected when using addition on the two values, 2147483647 and 21474836.

As Wikipedia explains overflow:

Arithmetic overflow, a condition that occurs when a calculation produces a result that is greater than what a given register can store or represent

With the first value being the greatest positive value a signed integer can store, the result of the addition is greater then what a signed integer can store.

My guess is that when the script calculates the interest, it doesn't check if the value will overflow or not.

I don't remember how the emulator works with overflowing values, but do you get a negative bank value if you deposit more money?

Edited July 9, 2012 by plankt

[Feistz]

The error itself in english:

Warning. Overflow detected when using addition on the two values, 2147483647 and 21474836.

As Wikipedia explains overflow:

Arithmetic overflow, a condition that occurs when a calculation produces a result that is greater than what a given register can store or represent

With the first value being the greatest positive value a signed integer can store, the result of the addition is greater then what a signed integer can store.

My guess is that when the script calculates the interest, it doesn't check if the value will overflow or not.

I don't remember how the emulator works with overflowing values, but do you get a neegative bank value if you dposit more money?

Thanks for the reply, unfortunately, i cannot test it because whenever i want to deposit or withdraw money, the NPC will stuck

BUMP! Can someone fix this script and error for me?

[malufett]

what is your server's maximum zeny??

[Feistz]

2 billion. I believe that is the max amount you can set in rAthena right?

[malufett]

yes it can.... up to INT_MAX(2147483647) however your script doesn't check if the variable is going to be over the max value when the interest is added....

therefore you must add the max checking....

[Feistz]

yes it can.... up to INT_MAX(2147483647) however your script doesn't check if the variable is going to be over the max value when the interest is added....

therefore you must add the max checking....

how can i exactly add this checking? can you modify the script for me?

[malufett]

sorry but I can't modify the script ATM...

but try this

if(  #3rdbank > 2147483647 )
 set #3rdbank, 2147483647;

add this after the adding of interest....

[Euphy]

@malufett: That wouldn't work, you'd get an overflow error before the check occurs. o:

[malufett]

oh...yeah..it must be

if(  (#3rdbank+@int) > 2147483647 )
        set #3rdbank, 2147483647;

just add before the adding and skip the adding when this is set to true...

thanks Euphy....

[Feistz]

oh...yeah..it must be

if(  (#3rdbank+@int) > 2147483647 )
	 set #3rdbank, 2147483647;

just add before the adding and skip the adding when this is set to true...

thanks Euphy....

oh...yeah..it must be

if(  (#3rdbank+@int) > 2147483647 )
	 set #3rdbank, 2147483647;

just add before the adding and skip the adding when this is set to true...

thanks Euphy....

Which part of script do I need to add this exactly?