nsis installer: Fix mouse-over descriptions for emulators

We use the nsis.py script to write out an installer script Section
for each emulator executable, so the exact set of Sections depends on
which executables were built.  However the part of qemu.nsi which
specifies mouse-over descriptions for each Section still has a
hard-coded and very outdated list (with just i386 and alpha).  This
causes two problems.  Firstly, if you build the installer for a
configuration where you didn't build the i386 binaries you get
warnings like this:
  warning 6000: unknown variable/constant "{Section_i386}" detected, ignoring (macro:_==:1)
  warning 6000: unknown variable/constant "{Section_i386w}" detected, ignoring (macro:_==:1)
(this happens in our gitlab CI jobs, for instance).
Secondly, most of the emulators in the generated installer don't have
any mouseover text.

Make nsis.py generate a second output file which has the necessary
MUI_DESCRIPTION_TEXT lines for each Section it creates, so we can
include that at the right point in qemu.nsi to set the mouse-over
text.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20220305105743.2384766-4-peter.maydell@linaro.org

qemu.nsi

@@ -228,10 +228,7 @@ SectionEnd
 ; Descriptions (mouse-over).
 !insertmacro MUI_FUNCTION_DESCRIPTION_BEGIN
     !insertmacro MUI_DESCRIPTION_TEXT ${SectionSystem}  "System emulation."
-    !insertmacro MUI_DESCRIPTION_TEXT ${Section_alpha}  "Alpha system emulation."
-    !insertmacro MUI_DESCRIPTION_TEXT ${Section_alphaw} "Alpha system emulation (GUI)."
-    !insertmacro MUI_DESCRIPTION_TEXT ${Section_i386}   "PC i386 system emulation."
-    !insertmacro MUI_DESCRIPTION_TEXT ${Section_i386w}  "PC i386 system emulation (GUI)."
+!include "${BINDIR}\system-mui-text.nsh"
     !insertmacro MUI_DESCRIPTION_TEXT ${SectionTools} "Tools."
 !ifdef DLLDIR
     !insertmacro MUI_DESCRIPTION_TEXT ${SectionDll}   "Runtime Libraries (DLL)."

scripts/nsis.py

@@ -33,7 +33,9 @@ def main():
         subprocess.run(["make", "install", "DESTDIR=" + destdir + os.path.sep])
         with open(
             os.path.join(destdir + args.prefix, "system-emulations.nsh"), "w"
-        ) as nsh:
+        ) as nsh, open(
+            os.path.join(destdir + args.prefix, "system-mui-text.nsh"), "w"
+        ) as muinsh:
             for exe in sorted(glob.glob(
                 os.path.join(destdir + args.prefix, "qemu-system-*.exe")
             )):
@@ -49,6 +51,15 @@ def main():
                         arch, exe
                     )
                 )
+                if arch.endswith('w'):
+                    desc = arch[:-1] + " emulation (GUI)."
+                else:
+                    desc = arch + " emulation."
+
+                muinsh.write(
+                    """
+                !insertmacro MUI_DESCRIPTION_TEXT ${{Section_{0}}} "{1}"
+                """.format(arch, desc))
 
         for exe in glob.glob(os.path.join(destdir + args.prefix, "*.exe")):
             signcode(exe)