Large and Blocked Zip Issue

[Angus Robertson]

I use VCLZip 3.04 to zip up CCTV footage from public transport vehicles in the UK. Corrupted zips mean the police are unable to use the CCTV in court, or trace terrorists, so it's important there are no errors.

We have three main problems:

1 - We use 50 meg block zips since they have to be sent over WLAN, and rarely these will not unzip, giving a ZLIB error.

2 - If the original archive goes over 2 gigs, we get an exception. I fixed this by commenting out a redundant line in kp_unzipp.pas which gave a range error due to SetSize in TStream not supporting Int64.

zip_out_file.Size := file_info.uncompressed_size;

3 - Orginal archives over 4 gigs were truncated, looked like the size was copped to an longword.

I've previously checked the download and news pages for newer versions than 3.04 and never found them. But today I found this forum with discussion about 3.05 and all the above problems.

Problem 2 seems to have gone away due to that line setting a size of 0. Problem 3 also seems to be fixed.

There is a comment in the source about a fix 12 months ago for CD spanned parts, but it would be nice to know how this was fixed, and whether others can confirm that
blocked zips can now always be unzipped?

It really would be sensible to put some comments on the main web pages about this new release, so others don't waste all the time I've spent in the last six months looking for such problems.

Angus

[Kevin]

Angus,

You are right, I can't disagree with you. I have not had much time to devote to the upkeep of the VCLZip distribution and the website. However, just tonight I uploaded VCLZip 3.06 and modified the website to reflect this. I am hoping that I will have more time to devote now that some other things have quieted down... for now.

Sorry, I honestly don't remember exactly what modification was made for the CD Spanning problem. I will look through the code to see if I can tell what was changed.

Also, remember, besides this forum I also offer support through email. While I prefer the use of this forum, I know that there are times when I can't check the forum every day, so if I don't respond then email is fine.

Thanks,

Kevin

[Angus Robertson]

Many thanks for the new release, and the announcement in the Borland newsgroups that sent me, and probably lots of other people, back here.

One final thing, it would be nice to jump to ZLIB 1.2.3, which has security fixes over 1.2.2. I noted Dennis Passmore said he got it working a few weeks ago, but when I tried to replace the 1.2.2 OBJs with 1.2.3s someone else compiled, I got an error on the first call to Zlib, I was not sure if the version literal was meant to stay as 1.2.2 or change as well.

Angus

[Kevin]

I wanted to get the new version out, so I held off on changing the zlib version for now. I will change that and deliver it as build 2 after I have evaluation versions for the version 3.06.

Kevin