* admin/nt/dist-build/emacs.nsi: (Uninstall) delete only one Emacs

Previously, the uninstaller would recursively, unconditionally, remove
the parent folder in which Emacs was installed (the folder selected by
when running the installer), into which the installer places a folder
named for the given release (e.g. emacs-30.1).  This was a problem
during uinstalation when the selected folder contained other versions of
Emacs the user did not wish to remove.  Additionally, deleting Start Menu
short-cuts did not work (bug#68756).

Some installer language now better reflects that users are not
required to "Accept" the GNU Public License in order to use (etc.)
Emacs (bug#67667).

Users selections related to where to create (or not create) Start Menu
shortcuts are no longer ignored. (bug#75013)

Emacs (as installed by the installer) can now be uninstalled via
Windows' Add/Remove Progrms Control Panel.

The uninstaller will now remove (empty) parent folders, both under
Program Files and (when creation of shortcuts is enabled) under the
select Start Menu location.

admin/nt/dist-build/emacs.nsi

@@ -8,7 +8,10 @@ Outfile "emacs-${OUT_VERSION}-installer.exe"
 SetCompressor /solid lzma
 
 Var StartMenuFolder
+Var UninstallerPath
 
+!define UNINST_KEY \
+    "Software\Microsoft\Windows\CurrentVersion\Uninstall\emacs-${VERSION_BRANCH}"
 
 !define MUI_WELCOMEPAGE_TITLE "Emacs"
 !define MUI_WELCOMEPAGE_TITLE_3LINES
@@ -20,16 +23,27 @@ Var StartMenuFolder
 
 !insertmacro MUI_PAGE_WELCOME
 
-
-!define MUI_LICENSEPAGE_TEXT_TOP "The GNU General Public License"
+# licensing/about click-though page
+!define MUI_PAGE_HEADER_TEXT "Emacs is Free Software"
+!define MUI_PAGE_HEADER_SUBTEXT "A component of the GNU operating system."
+!define MUI_LICENSEPAGE_TEXT_TOP "This program is free software."
+!define MUI_LICENSEPAGE_TEXT_BOTTOM "You can redistribute this program and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License (as above), or (at your option) any later version."
+!define MUI_LICENSEPAGE_BUTTON "OK"
 !insertmacro MUI_PAGE_LICENSE "emacs-${VERSION_BRANCH}\share\emacs\${EMACS_VERSION}\lisp\COPYING"
 
+# user option page: installation path
 !insertmacro MUI_PAGE_DIRECTORY
-!insertmacro MUI_PAGE_INSTFILES
 
+# user option page: start menu shortcut
 !insertmacro MUI_PAGE_STARTMENU Application $StartMenuFolder
 
+# user option confirm/begin install
+!insertmacro MUI_PAGE_INSTFILES
+
+# uninstaller confirmation/options (no options)
 !insertmacro MUI_UNPAGE_CONFIRM
+
+# uninstaller begin
 !insertmacro MUI_UNPAGE_INSTFILES
 
 !insertmacro MUI_LANGUAGE "English"
@@ -39,23 +53,35 @@ function .onInit
     StrCpy $INSTDIR "$PROGRAMFILES64\Emacs"
 functionend
 
-
+# main section logic, run after confirming installation
 Section
 
-  SetOutPath $INSTDIR
+  # insisting on installing shortcuts for "all users"
+  # might ensure uninstall can remove shortcuts we created
+  # SetShellVarContext all
 
+  # extract program files
+  SetOutPath $INSTDIR
   File /r emacs-${VERSION_BRANCH}
 
   # define uninstaller name
-  WriteUninstaller $INSTDIR\Uninstall.exe
+  StrCpy $UninstallerPath "$INSTDIR\Uninstall-${VERSION_BRANCH}.exe"
+
+  # create uninstaller
+  WriteUninstaller "$UninstallerPath"
+
+  # add registry key to enable uninstall from control panel
+  WriteRegStr HKLM "${UNINST_KEY}" "DisplayName" "GNU Emacs ${VERSION_BRANCH}"
+  WriteRegStr HKLM "${UNINST_KEY}" "UninstallString" "$\"$UninstallerPath$\""
 
-  !insertmacro MUI_STARTMENU_WRITE_BEGIN Application
   ;Create shortcuts
+  !insertmacro MUI_STARTMENU_WRITE_BEGIN Application
   CreateDirectory "$SMPROGRAMS\$StartMenuFolder"
-  CreateShortcut "$SMPROGRAMS\$StartMenuFolder\Uninstall.lnk" "$INSTDIR\Uninstall.exe"
-
+  CreateShortcut "$SMPROGRAMS\$StartMenuFolder\Uninstall.lnk" \
+      "$UninstallerPath"
+  CreateShortCut "$SMPROGRAMS\$StartMenuFolder\Emacs.lnk" \
+      "$INSTDIR\emacs-${VERSION_BRANCH}\bin\runemacs.exe"
   !insertmacro MUI_STARTMENU_WRITE_END
-  CreateShortCut "$SMPROGRAMS\$StartMenuFolder\Emacs.lnk" "$INSTDIR\emacs-${VERSION_BRANCH}\bin\runemacs.exe"
 SectionEnd
 
 
@@ -63,15 +89,50 @@ SectionEnd
 # the section will always be named "Uninstall"
 Section "Uninstall"
 
-  # Always delete uninstaller first
-  Delete "$INSTDIR\Uninstall.exe"
+  # remove All Users shortcuts only
+  # SetShellVarContext all
 
-  # now delete installed directory
-  RMDir /r "$INSTDIR"
-  RMDir "$INSTDIR"
+  # retreive/recalculate uninstaller location
+  StrCpy $UninstallerPath "$INSTDIR\Uninstall-${VERSION_BRANCH}.exe"
 
+  # remove registry key
+  DeleteRegKey HKLM "${UNINST_KEY}"
+
+  # delete uninstaller
+  Delete "$INSTDIR\Uninstall-${VERSION_BRANCH}.exe"
+
+  # retreive/reclculate startmenu shortcuts location
   !insertmacro MUI_STARTMENU_GETFOLDER Application $StartMenuFolder
+  StrCpy $StartMenuFolder "$SMPROGRAMS\$StartMenuFolder"
+
+  # remove Start Menu Program shortcuts
+  Delete "$StartMenuFolder\Emacs.lnk"
+  Delete "$StartMenuFolder\Uninstall.lnk"
+
+  # remove empty startmenu parents up to $SMPROGRAMS
+  startMenuDeleteLoop:
+    ClearErrors
+    RMDir $StartMenuFolder
+    GetFullPathName $StartMenuFolder "$StartMenuFolder\.."
+    IfErrors startMenuDeleteLoopDone
+    StrCmp $StartMenuFolder $SMPROGRAMS startMenuDeleteLoopDone startMenuDeleteLoop
+
+  # we're basically using GOTO, above, so we should get here..
+  startMenuDeleteLoopDone:
+
+  # next we remove stuff from program-files/instalation path
+  # start with recursive delete of the Emacs we installed
+  RMDir /r "$INSTDIR\emacs-${VERSION_BRANCH}"
+
+  # now walk parents of installation directory, deleting if empty
+  instDirDeleteLoop:
+    ClearErrors
+    RMDir $INSTDIR
+    GetFullPathName $INSTDIR "$INSTDIR\.."
+    IfErrors instDirDeleteLoopDone
+    StrCmp $INSTDIR $PROGRAMFILES64 instDirDeleteLoopDone instDirDeleteLoop
+
+  # final clean-up (after removing from startmenu and progfiles)
+  instDirDeleteLoopDone:
 
-  Delete "$SMPROGRAMS\$StartMenuFolder\Uninstall.lnk"
-  RMDir "$SMPROGRAMS\$StartMenuFolder"
 SectionEnd