How can i call a dll that import another dll using NSIS system plugin

Question

I am newbie of NSIS installer. I gotta say NSIS deployment is awesome . but lately I am encountered a problem.

I am using NSIS script to call let's say A.dll which compiled using Visual C++ and export some C functions. and A.dll import B.dll. So I extract them (A.dll and B.dll) to $PLUGINSDIR at the very beginning of installation.

After that I call System::call to call let's say "test()" of A.dll. but it always return "error". I also did a test removing import of B.dll and "test()" works and returns the value of what I expected.

here is the code:

;extract dll file

InitPluginsDir

SetOutPath $PLUGINSDIR

File "A.dll"

File "B.dll"

...........

;call it
code:
System::Call "$PLUGINSDIR\A::test() i.r0"

$0 return "error"

after removing import of B.dll and re-compile A.dll. test() works fine.

Can anybody explain How can I call a dll that imports another dll using NSIS system plugin? Thanks in advance. sorry for the poor English. hope you guys understand what I mean.

Answer 1

The loader cannot find B.dll so LoadLibrary (called by system.dll) on A.dll is going to fail.

You can set the working directory:

Push $outdir ; Save current, not required
SetOutPath $pluginsdir
System::Call "$PLUGINSDIR\A::test() i.r0"
pop $outdir
SetOutPath $outdir ; Restore

or you can load B.dll yourself:

System::Call 'KERNEL32::LoadLibrary(t "$PLUGINSDIR\B.dll")i.s'
System::Call "$PLUGINSDIR\A::test() i.r0"
System::Call 'KERNEL32::FreeLibrary(is)'