[PATCH v2 for-6.2] meson.build: Support ncurses on MacOS and OpenBSD

[Stefan Weil]

MacOS provides header files for curses 5.7 with support
for wide characters, but requires _XOPEN_SOURCE_EXTENDED=1
to activate that.

By default those old header files are used even if there
is a newer Homebrew installation of ncurses 6.2 available.

Change also the old macro definition of NCURSES_WIDECHAR
and set it to 1 like it is done in newer versions of
curses.h when _XOPEN_SOURCE_EXTENDED=1 is defined.

OpenBSD has the same version of ncurses and needs the same fix.

Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
---

v2:
- Only define _XOPEN_SOURCE_EXTENDED when curses.h is used.
- Extended to fix OpenBSD, too (untested!)

 meson.build | 5 ++++-
 ui/curses.c | 4 ++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/meson.build b/meson.build
index e2d38a43e6..16b3f748f4 100644
--- a/meson.build
+++ b/meson.build
@@ -681,6 +681,9 @@ iconv = not_found
 curses = not_found
 if have_system and not get_option('curses').disabled()
   curses_test = '''
+    #if defined(__APPLE__) || defined(__OpenBSD__)
+    #define _XOPEN_SOURCE_EXTENDED 1
+    #endif
     #include <locale.h>
     #include <curses.h>
     #include <wchar.h>
@@ -704,7 +707,7 @@ if have_system and not get_option('curses').disabled()
     endif
   endforeach
   msg = get_option('curses').enabled() ? 'curses library not found' : ''
-  curses_compile_args = ['-DNCURSES_WIDECHAR']
+  curses_compile_args = ['-DNCURSES_WIDECHAR=1']
   if curses.found()
     if cc.links(curses_test, args: curses_compile_args, dependencies: [curses])
       curses = declare_dependency(compile_args: curses_compile_args, 
dependencies: [curses])
diff --git a/ui/curses.c b/ui/curses.c
index e4f9588c3e..861d63244c 100644
--- a/ui/curses.c
+++ b/ui/curses.c
@@ -38,6 +38,10 @@
 #include "ui/input.h"
 #include "sysemu/sysemu.h"
 
+#if defined(__APPLE__) || defined(__OpenBSD__)
+#define _XOPEN_SOURCE_EXTENDED 1
+#endif
+
 /* KEY_EVENT is defined in wincon.h and in curses.h. Avoid redefinition. */
 #undef KEY_EVENT
 #include <curses.h>
-- 
2.30.2