ASSERT question *excuse my newbie-ness*

[melo_1981]

hello:

i would like to write a global function that will validate pointers (based on a range of addresses) for newly added code. Several other functions will call this global function, and if the value is bad, i want to do an assert.

what would the code (psuedo-code) look like for this?

thanks for any and all help.

[redhead]

Give me some time, and I'll get back to this one.. Just havn't come up with a simple example yet..

[melo_1981]

Originally Posted by redhead

Give me some time, and I'll get back to this one.. Just havn't come up with a simple example yet..

a global function that will validate pointers (based on a range [m,n] of memory addresses) for newly added code. Several other functions will call this global function, and if the value is bad, i want to do an assert.

so something like:

void myAssert( pointerType p1)
{

// check for valid memory address
if ( (p1 < m) || (p1 > n ) )
assert1(true); // do an assert if pointer is not in valid range
else
assert1(false);
}

i get all confused with * and & when it has to do with memory addresses, but that's basically the jist of it.

[redhead]

How do you verify the address is correct ?? do you have some sort of strickt instruction loading routine of your own, or what ??
Let me repeat myself, how do you verify the address is correct ??
Uppon execution you normaly wouldn't know where in the memory space your jump/branch instructions will be placed, they are just added to the runtime heap, which you dont even know where will start at, this can only be controled if you're working in an envirenment, where you yourself have written the loading routine..
Or perhaps you want to check if the memory allocated in a struct/class is allocated within the structs memory range.. then again this can't be verified, since the memory allocation normaly asserts a jump or pointer instruction to where the remainder of hte memory allocated will be available at..
I'm confused.....

If at some point I do get what you're looking for here, I will come up with a way to achieve it, but so far that looks to be some nasty pointer arithmetik.

[melo_1981]

i am given a dedicated range of valid addresses (hardware). i want the function to take the pointer, validate the adress is in the specified range (if it is not, then do an assert).

sorry if i'm not clear...

[redhead]

hmmm.. I'm still not clear if I'm getting this..
And I could be way off.. But wouldn't something like this work ??

#define MIN 0xfe343468
#define MAX 0xfff23435
#define ASSERT(p) (assert((MIN >= &(p) && &(p) <= MAX ));)
// blah blah, my code..
ASSERT(hardware_access)

Or are you working in some kernel-space, where you use mmap() with /dev/kmem to make the needed memory available for your routine ??