graphics/povray37: fix build with libc++ 19

As noted in the libc++ 19 release notes [1], std::char_traits<> is now
only provided for char, char8_t, char16_t, char32_t and wchar_t, and any
instantiation for other types will fail.

This causes graphics/povray37 to fail to compile with clang 19 and
libc++ 19, resulting in errors similar to:

  /usr/include/c++/v1/string:820:42: error: implicit instantiation of undefined template 'std::char_traits<unsigned short>'
    820 |   static_assert(is_same<_CharT, typename traits_type::char_type>::value,
        |                                          ^
  ./base/configbase.h:159:19: note: in instantiation of template class 'std::basic_string<unsigned short>' requested here
    159 | inline UCS2String ASCIItoUCS2String(const char *s)
        |                   ^
  /usr/include/c++/v1/__fwd/string.h:23:29: note: template is declared here
     23 | struct _LIBCPP_TEMPLATE_VIS char_traits;
        |                             ^

This can be fixed by defining `POVMSUCS2` as `char16_t` instead of
`unsigned short`, `UCS2` as `char16_t` instead of `unsigned short`, and
`UCS4` as `char32_t` instead of `unsigned int` in the passed-in
`CPPFLAGS` variable.

Also, patch up `vfe.cpp` and `vfeconf.h` to use `char16_t` and
`u16string` instead of the non-standard types.

[1] https://libcxx.llvm.org/ReleaseNotes/19.html#deprecations-and-removals

PR:		282645
Approved by:	bsd@philippost.de (maintainer)
MFH:		2024Q4

1 files changed, 19 insertions, 0 deletions

diff --git a/graphics/povray37/files/patch-vfe_vfeconf.h b/graphics/povray37/files/patch-vfe_vfeconf.h
new file mode 100644
index 000000000000..e0761680ed1f
--- /dev/null
+++ b/graphics/povray37/files/patch-vfe_vfeconf.h
@@ -0,0 +1,19 @@
+--- vfe/vfeconf.h.orig	2021-07-08 09:56:01 UTC
++++ vfe/vfeconf.h
+@@ -61,12 +61,12 @@ namespace vfe
+   int vfe_POVMS_Sys_QueueSend(POVMS_Sys_QueueNode *q, void *p, int l) ;
+   int Allow_File_Write (const char *Filename, const unsigned int FileType);
+   int Allow_File_Read (const char *Filename, const unsigned int FileType);
+-  int Allow_File_Read (const unsigned short *Filename, const unsigned int FileType);
+-  int Allow_File_Write (const unsigned short *Filename, const unsigned int FileType);
++  int Allow_File_Read (const char16_t *Filename, const unsigned int FileType);
++  int Allow_File_Write (const char16_t *Filename, const unsigned int FileType);
+   POVMS_Sys_Thread_Type POVMS_GetCurrentThread();
+   void vfeAssert (const char *message, const char *filename, int line) ;
+-  FILE *vfeFOpen (const std::basic_string<unsigned short>& name, const char *mode);
+-  bool vfeRemove (const std::basic_string<unsigned short>& name);
++  FILE *vfeFOpen (const std::u16string& name, const char *mode);
++  bool vfeRemove (const std::u16string& name);
+ 
+ #if defined _DEBUG
+   void *vfe_POVMS_Sys_Malloc(size_t size, const char *func, const char *file, int line) ;