use the UAC plugin to elevate uninstaller

cmake/templates/NSIS.template.in

@@ -30,8 +30,10 @@
 
 ;--------------------------------
 ;General
-
   !ifdef INNER
+    ; leverage the UAC NSIS plugin to promote uninstaller to elevated privileges
+    !include UAC.nsh
+
     !echo "Inner invocation"                  ; just to see what's going on
 
     ; Require user only for temp installer
@@ -62,7 +64,7 @@
     ; The Inner invocation has written an uninstaller binary for us.
     ; We need to sign it if it's a production or PR build.
     !if @PRODUCTION_BUILD@ == 1
-      !system '"@SIGNTOOL_EXECUTABLE@" sign /f %HF_PFX_FILE% /p %HF_PFX_PASSPHRASE% /tr http://tsa.starfieldtech.com /td SHA256 $%TEMP%\uninstaller.exe' = 0
+      !system '"@SIGNTOOL_EXECUTABLE@" sign /f %HF_PFX_FILE% /p %HF_PFX_PASSPHRASE% /tr http://tsa.starfieldtech.com /td SHA256 $%TEMP%\Uninstall.exe' = 0
     !endif
 
     ; Good.  Now we can carry on writing the real installer.
@@ -685,7 +687,7 @@ Section "-Core installation"
   ;Package the signed uninstaller produced by the inner loop
   !ifndef INNER
     ; this packages the signed uninstaller
-    File $%TEMP%\uninstaller.exe
+    File $%TEMP%\Uninstaller.exe
   !endif
 
   Push "DisplayName"
@@ -928,6 +930,29 @@ FunctionEnd
 ; determine admin versus local install
 Function un.onInit
 
+  ; attempt to elevate the uninstaller to admin status
+  uac_tryagain:
+  !insertmacro UAC_RunElevated
+  ${Switch} $0
+  ${Case} 0
+    ${IfThen} $1 = 1 ${|} Quit ${|} ;we are the outer process, the inner process has done its work, we are done
+    ${IfThen} $3 <> 0 ${|} ${Break} ${|} ;we are admin, let the show go on
+    ${If} $1 = 3 ;RunAs completed successfully, but with a non-admin user
+      MessageBox mb_YesNo|mb_IconExclamation|mb_TopMost|mb_SetForeground "The uninstaller requires admin privileges, try again" /SD IDNO IDYES uac_tryagain IDNO 0
+    ${EndIf}
+    ;fall-through and die
+
+  ${Case} 1223
+    MessageBox mb_IconStop|mb_TopMost|mb_SetForeground "The uninstaller requires admin privileges, aborting!"
+    Quit
+  ${Case} 1062
+    MessageBox mb_IconStop|mb_TopMost|mb_SetForeground "Logon service not running, aborting!"
+    Quit
+  ${Default}
+    MessageBox mb_IconStop|mb_TopMost|mb_SetForeground "Unable to elevate, error $0"
+    Quit
+  ${EndSwitch}
+
   ClearErrors
   UserInfo::GetName
   IfErrors noLM
@@ -994,6 +1019,7 @@ FunctionEnd
 
 !ifdef INNER
 Section "Uninstall"
+
   ReadRegStr $START_MENU SHCTX \
    "Software\Microsoft\Windows\CurrentVersion\Uninstall\@CPACK_PACKAGE_INSTALL_REGISTRY_KEY@" "StartMenu"
   ;MessageBox MB_OK "Start menu is in: $START_MENU"
@@ -1107,7 +1133,7 @@ Function .onInit
     ; the installer.  This is better than processing a command line option as it means
     ; this entire code path is not present in the final (real) installer.
 
-    WriteUninstaller "$%TEMP%\uninstaller.exe"
+    WriteUninstaller "$%TEMP%\Uninstall.exe"
 
     ; just bail out quickly when running the "inner" installer
     Quit