64-bit support

[SubJunk]

Hi @Nadahar , I was just playing around with a 64-bit fork of NSIS and noticed there are requests to make LockedList supported, there is a thread at https://forums.winamp.com/forum/developer-center/nsis-discussion/4635756-nsis-with-64-bit-support

I thought it was worth having an issue for here. Hope you're well!

[Nadahar]

Hi 😉

I must say that I don't remember the details, so I don't remember if I've explicitly tested the 64-bit version, but this one should already be 64-bit. There are both unicode and non-uncode 32-bit versions and one unicode-only 64-bit DLL in the ZIP file.

Do you have any indications that this one doesn't work with 64-bit?

[SubJunk]

I only tested briefly by copying the September 2025 release of a 64-bit NSIS project over the top of the official one https://github.com/negrutiu/nsis/releases and when I ran our build script the first error that appeared mentioned LockedList. That might not have been a true test though, I didn't try to debug it since I found that winamp.com thread mentioning LockedList

[Nadahar]

I've never actually tested with a 64-bit NSIS (since it doesn't really exist), but I know that LockedList is made to detect 64-bit processes, and only "64-bit code" can see those. So, as far as I can remember, there are some internal tricks when run in 32-bit mode where it checks if the OS is 64-bit, and then launches the 64-bit DLL.

You probably have to update the NSIS project to use to the 64-bit DLL for it to have a chance to work though.

[SubJunk]

Cool, I'm trying again now

[SubJunk]

I copied over that NSIS unofficial release, added LockedList64.dll to the new Plugins/amd64-unicode directory, updated this line https://github.com/UniversalMediaServer/UniversalMediaServer/blob/main/src/main/external-resources/windows/nsis-scripts/update.nsi#L74 to point to the DLL, and the build script outputs:

[INFO] [MAKENSIS] Plugin directories:
[INFO] [MAKENSIS]   src\main\external-resources\windows\nsis\Plugins\amd64-unicode
[INFO] [MAKENSIS] Plugin not found, cannot call LockedList::AddModule
[INFO] [MAKENSIS] Error in script "target\update.nsi" on line 76 -- aborting creation process

but like you said there is no real 64-bit NSIS so maybe it would be a waste of time to get this working. I get really slow performance from the LZMA compression part of NSIS and was curious about whether this would improve it, but it's probably not worth the risk of using an unofficial build.

[Nadahar]

Figuring out headers and calling convention etc. isn't my string suite, but I'm pretty sure that whatever the problem is, it's relatively minor, because I believe that I tested and verified that it actually works with 64 bit processes.

As you can see here: #1 (comment) we did some work on that whole "launch a 64-bit subprocess bit", so I know that it "works" in that sense. Whether it interfaces nicely with NSIS is a different matter of course.

When it comes to the compression speed, yes, it's slow, but it compresses "really hard". Try to loosen up the compression level a bit, and you'll see much improved speed. Back when NSIS was made, evey byte "counted", so it goes a long way to squeeze every saving it can out of the compression.