speedo,w32: Fix InstallDir usage and x64 install

* build-aux/speedo/w32/inst.nsi (InstallDir): Move to the
MUI definitions for clarity.
(MULTIUSER_INSTALLMODE_INSTDIR): Use pretty name.
(-gnupginst): Handle regviews and upgrades

--
As MultiUser.nsh sets the INSTDIR variable we have
to define MULTIUSER_USE_PROGRAMFILES64.

The resulting installer created by makensis itself
is still a 32bit binary we have to use SetRegView to
use the correct registry hive for 64 bit software.

To better handle the path switch from ProgramFiles (x86)
to ProgramFiles on update we now call the uninstaller
of the previous version before installing the new
version. This additionally ensures that there
are no leftover files and a dirty install directory
after some upgrades.

build-aux/speedo/w32/inst.nsi

@@ -45,12 +45,11 @@ Unicode true
 !define PACKAGE_SHORT "gnupg"
 !define PRETTY_PACKAGE "GNU Privacy Guard"
 !define PRETTY_PACKAGE_SHORT "GnuPG"
+!define INSTALL_DIR "GnuPG"
 !define COMPANY "The GnuPG Project"
 !define COPYRIGHT "Copyright (C) 2024 g10 Code GmbH"
 !define DESCRIPTION "GnuPG: The GNU Privacy Guard for Windows"
 
-!define INSTALL_DIR "GnuPG"
-
 !define WELCOME_TITLE_ENGLISH \
  "Welcome to the installation of GnuPG"
 
@@ -91,6 +90,10 @@ SetCompressor lzma
 !include "LogicLib.nsh"
 !include "x64.nsh"
 
+# Set the default installation directory. This is used by
+# MultiUser.nsh which then sets the actual INSTDIR.
+InstallDir "$PROGRAMFILES64\${INSTALL_DIR}"
+
 # We support user mode installation but prefer system wide
 !define MULTIUSER_EXECUTIONLEVEL Highest
 !define MULTIUSER_MUI
@@ -99,7 +102,8 @@ SetCompressor lzma
 !define MULTIUSER_INSTALLMODE_DEFAULT_REGISTRY_VALUENAME ""
 !define MULTIUSER_INSTALLMODE_INSTDIR_REGISTRY_KEY "Software\${PACKAGE_SHORT}"
 !define MULTIUSER_INSTALLMODE_INSTDIR_REGISTRY_VALUENAME "Install Directory"
-!define MULTIUSER_INSTALLMODE_INSTDIR "${PACKAGE_SHORT}"
+!define MULTIUSER_INSTALLMODE_INSTDIR "${INSTALL_DIR}"
+!define MULTIUSER_USE_PROGRAMFILES64
 !include "MultiUser.nsh"
 
 # Set the package name.  Note that this name should not be suffixed
@@ -115,12 +119,6 @@ OutFile "${NAME}-${VERSION}_${BUILD_DATESTR}.exe"
 #Icon "${TOP_SRCDIR}/doc/logo/gnupg-logo-icon.ico"
 #UninstallIcon "${TOP_SRCDIR}/doc/logo/gnupg-logo-icon.ico"
 
-# Set the installation directory.
-!ifndef INSTALL_DIR
-!define INSTALL_DIR "GnuPG"
-!endif
-InstallDir "$PROGRAMFILES64\${INSTALL_DIR}"
-
 # Add version information to the file properties.
 VIProductVersion "${PROD_VERSION}"
 VIAddVersionKey "ProductName" "${PRETTY_PACKAGE_SHORT} (${VERSION})"
@@ -576,8 +574,32 @@ FunctionEnd
 #
 # Define the installer sections.
 #
-
+Var MYTMP
 Section "-gnupginst"
+  # Check if GnuPG is already installed and uninstall it (Update)
+  #
+  # Before GnuPG 2.5 the Windows installer was 32 bit
+  # so look for 32 bit installations, too.
+  SetRegView 32
+uninst_old_version:
+  ClearErrors
+  ReadRegStr $0 SHCTX "Software\Microsoft\Windows\CurrentVersion\Uninstall\GnuPG" "UninstallString"
+  IfErrors skip_uninst 0
+  ReadRegStr $1 SHCTX "Software\Microsoft\Windows\CurrentVersion\Uninstall\GnuPG" "InstallLocation"
+  IfErrors skip_uninst 0
+
+  ExecWait '$0 /S _?=$1'
+  Delete /REBOOTOK "$1\gnupg-uninstall.exe"
+  RmDir "$1"
+skip_uninst:
+  StrCmp $MYTMP "1" skip_uninst2 0
+  SetRegView 64
+  StrCpy $MYTMP "1"
+  goto uninst_old_version
+skip_uninst2:
+
+  # We are now 64 bit only
+  SetRegView 64
   SetOutPath "$INSTDIR"
 
   File "${BUILD_DIR}/README.txt"
@@ -590,23 +612,6 @@ Section "-gnupginst"
 
   WriteRegStr SHCTX "Software\GnuPG" "Install Directory" $INSTDIR
 
-  # If we are reinstalling, try to kill a possible running gpa using
-  # an already installed gpa.
-  ifFileExists "$INSTDIR\bin\launch-gpa.exe"  0 no_uiserver
-    nsExec::ExecToLog '"$INSTDIR\bin\launch-gpa" "--stop-server"'
-
-  no_uiserver:
-
-  # If we are reinstalling, try to kill a possible running agent using
-  # an already installed gpgconf.
-
-  ifFileExists "$INSTDIR\bin\gpgconf.exe"  0 no_gpgconf
-    nsExec::ExecToLog '"$INSTDIR\bin\gpgconf" "--kill" "dirmngr"'
-    nsExec::ExecToLog '"$INSTDIR\bin\gpgconf" "--kill" "gpg-agent"'
-    nsExec::ExecToLog '"$INSTDIR\bin\gpgconf" "--kill" "keyboxd"'
-
-  no_gpgconf:
-
   # Add the bin directory to the PATH
   Push "$INSTDIR\bin"
   Call AddToPath
@@ -1466,22 +1471,11 @@ Function .onInit
 
   Call G4wRunOnce
 
-   ${IfNot} ${RunningX64}
-       MessageBox MB_OK "Sorry this version runs only on x64 machines"
-       Abort
-   ${EndIf}
-
-   SetOutPath $TEMP
-#!ifdef SOURCES
-#  File /oname=gpgspltmp.bmp "${TOP_SRCDIR}/doc/logo/gnupg-logo-400px.bmp"
-#  # We play the tune only for the soruce installer
-#  File /oname=gpgspltmp.wav "${TOP_SRCDIR}/src/gnupg-splash.wav"
-#  g4wihelp::playsound $TEMP\gpgspltmp.wav
-#  g4wihelp::showsplash 2500 $TEMP\gpgspltmp.bmp
-
-#  Delete $TEMP\gpgspltmp.bmp
-#  # Note that we delete gpgspltmp.wav in .onInst{Failed,Success}
-#!endif
+  ${IfNot} ${RunningX64}
+      MessageBox MB_OK "Sorry this version runs only on x64 machines"
+      Abort
+  ${EndIf}
+  SetRegView 64
 
   # We can't use TOP_SRCDIR dir as the name of the file needs to be
   # the same while building and running the installer.  Thus we
@@ -1506,6 +1500,7 @@ initDone:
 FunctionEnd
 
 Function "un.onInit"
+  SetRegView 64
   !insertmacro MULTIUSER_UNINIT
 FunctionEnd
 
@@ -1614,7 +1609,6 @@ SectionEnd
 #
 # Now for the generic parts to end the installation.
 #
-Var MYTMP
 
 # Last section is a hidden one.
 Section