NSIS plugin example

[PeterH]

Noticed that there's a "half-done" example to be found in the forum (thanks for the jumpstart, sepp!) so I tinkered a little and managed to accomplish this to fully support the return values as well in NSIS:

Code: Select all

; Minimal PureBasic NSIS plugin for stack handling test
; In this example compiled with /UNICODE and as x86.
; Filename: TestPlugin.dll

Structure stack_t
  *Next.stack_t
  text.s{1024}
EndStructure

Procedure.s PopString(*stacktop_pointer)
  Protected result.s = ""
  Protected *stacktop.stack_t = PeekI(*stacktop_pointer)
  If *stacktop
    result = PeekS(@*stacktop\text, 1024)
    PokeI(*stacktop_pointer, *stacktop\Next)
    GlobalFree_(*stacktop)
  EndIf
  ProcedureReturn result
EndProcedure

Procedure PushString(str.s, *stacktop_pointer)
  Protected *new.stack_t = GlobalAlloc_(#GMEM_FIXED, SizeOf(stack_t))
  If *new
    PokeS(@*new\text, str, 1024)
    *new\Next = PeekI(*stacktop_pointer)
    PokeI(*stacktop_pointer, *new)
  EndIf
EndProcedure

ProcedureCDLL TestPlugin(hwndParent, string_size, *variables, *stacktop, *extra)
  Protected *stacktop_pointer = *stacktop
  Protected param.s = PopString(*stacktop_pointer)
  MessageRequester("TestPlugin", param)
  PushString("42", *stacktop_pointer)
EndProcedure 

Code: Select all

; Minimal NSIS script to test the PureBasic TestPlugin DLL
; Assuming the TestPlugin.dll has been placed in the NSIS\Plugins\x86-unicode folder

Unicode True

Name "TestPlugin Test"
OutFile "TestPluginTest.exe"

Section "Test TestPlugin"
  DetailPrint "Calling TestPlugin with parameter: HelloFromNSIS"
  TestPlugin::TestPlugin "HelloFromNSIS"
  Pop $0
  DetailPrint "TestPlugin result: $0"
  ; Will output "42", as a string since all return values in NSIS are strings
SectionEnd 

I hope it might help someone at some point. I use it because the multisz support for the registry it horrible to work with in NSIS, even if using REG_MULTI_SZ_Reader and REG_MULTI_SZ_Editor

[Quin]

Whoa, now that is cool. Thanks for sharing!

[PeterH]

Whoa, now that is cool. Thanks for sharing!

My pleasure. Happy to contribute. In fact so happy that it took me less than 10 minutes from testing it to posting it.

If you want to compete with the sizes of other NSIS-plugins, try a version <4 or PureBasic and you should get a really small DLL. For me the 100-150kb addition to an installer that takes up 6-10MB is not an issue, but for smaller apps it might be of interest. Beware of the risk that some antivirus goes bonkers though.