Jump to content

How to SAFELY access memory or copy memory to array?


Mbee
 Share

Recommended Posts

I'm using a UDF (in this case, the FreeImage UDF, modified by Iczer and found here: https://www.autoitscript.com/forum/topic/95357-freeimage-library/?do=findComment&comment=1334983) that in some cases returns a pointer or handle to image data in memory (in this case, the function " _FreeImage_GetBits()"). But in order to use this image data with other, more standard functions, I need to pass this image data as if it were stored as an ordinary AutoIt variable (a binary array).  How can I accomplish this?

A perfectly acceptable solution would be to somehow copy this binary data in memory to a standard AutoIt binary array, but I don't know how to do that either.

Please note that I'm only interested in safe, absolutely non-hacking-related help here!  Google has pointed me to various sites that discuss memory-related tricks that attempt to read memory data from other processes that seems to me to be focused on hacking and I strongly agree that they have absolutely no place in this forum!  But I have zero interest in such things -- I'm only interested in binary data within my own process.

Once upon a time @Ward published a UDF that might have helped here: Binary UDF (specifically, a function called _BinaryFromMemory()), but the download links have since all been crossed out, implying that either some more official way of doing such things had since been incorporated into standard AutoIt -or- that UDF was being abused in an undesired manner.

What is the recommended way of accomplishing what I need?

THANKS!

 

Edited by Mbee
typo
Link to comment
Share on other sites

Wow, thanks, @Andy G

I had started to look into using DllStructs and the related functions because they looked like the most promising approach, but all I was able to figure out was how to write and read the data in the structs and the like.  I had no clue how to deal with pointers.  But now I do!  Thanks again!

 

Link to comment
Share on other sites

59 minutes ago, AndyG said:

In AutoIt, you can create a dllstruct at the position of that pointer, and *voila* you have a bytearray.

$bytearray_struct = DllStructCreate("byte[" & $sizeofdata & "]", $pointertodata)
$data = DllStructGetData($bytearray_struct) ;bytearray

 

Um, @AndyG , I need a little more help, please.  The second line wouldn't compile, so I changed it to...

$data = DllStructGetData($bytearray_struct, 1)

But even so, when I tried to access $data as a byte array (for example, as follows):

$data[$i]

I received the following error message: "Error: Subscript used on non-accessible variable."

For the record, I don't truly need to access the data as a binary byte array myself, but I'm calling another UDF that apparently does need to access it that way...

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...