Md5 hash generation

21

You are brilliant :smiley: :smile: :rofl:

22

Hi,
I downloaded the code, but I never compiled an app which includes C code, so I tried to compile the application with Clarion 6.3 and got these errors:
Unresolved External _MD5Init in md5te002.obj
Unresolved External _MD5Update in md5te002.obj
Unresolved External _MD5Final in md5te002.obj

what am I suppose to do to solve this ?

Regards

23

working_6.3.zip (8.3 KB)

sk2107, does this work for you?

24

I will check.

Thank you

25

The exe was created and running fine thank you. but my main problem is getting the md5 of large files (more than 5 GB and could reach 20 GB in some cases). I don’t know if this code can help in this case.

Regards

26

Ah, yes, that would be a problem. I don’t think this code will help with that, sorry.

27

Thank you. but still it is a good example for me.

Regards

28

IF you need it to match something generated elsewhere, then make sure that the values match! I added MD5 using a DLL I found online after trying several other methods as none of them produced MD5 hash that was compatible with what PHP generated.

29

@sk2107; included is the md5 code with a small program; I think that it will compile in cw6; you can use it with large files, but check it first with some know results.
I have NOT tested it.

30

I tested it but still it is not giving the correct result for large files (more than 4GB) and I think the reason is that the DOS driver used has the limit of 4,294,967,295B for file or record. (Hope I am wrong).

Any how thank you for your contribution.

Regards

31

That limit of DOS driver Is not relevant. All that matter is if the file is bigger than the buffer. I checked the program with one file of 1.5MB and the result is correct.
Again, do your own test.
i uploaded a revised version.

32

no you are not wrong. You would need to use Win API for reading large files and use Big Ints (64 bit) for the offsets within the file.

I wrote a bigFile class maybe 7 or 8 years back that did that kind of thing. Maybe I can look at that code and create something that can do MD5 for large files > 4GB. Might take a few days as I am away on holidays at the moment.

33

Thank you

Best regards

34

sorry, you were right. You can not process files bigger than 4GB, you need to use CreateFileA (windows API).