Re: [RFA] defs.h: Define GDB_DEFAULT_TARGET_[WIDE_]CHARSET for Cygwin and MingW builds

[Corinna Vinschen <vinschen@redhat.com>]

On Mar  2 15:55, Tom Tromey wrote:
> >>>>> "Tom" == Tom Tromey <tromey@redhat.com> writes:
> 
> Tom> I agree, we need a gdbarch method.
> 
> Tom> I'll look into this today.
> 
> Here's a patch, please let me know what you think.
> 
> This patch nearly works -- it regresses on a Python test that looks at
> gdb.parameter('target-charset') directly and then gets confused by
> "auto".  I think the only solution for this is to add a new Python API.
> (It would be easy enough to just hack the test case somehow -- but the
> libstdc++ printers use this same idiom, so a real solution is needed.)
> 
> I wasn't sure where to put the Cygwin override; I took Daniel's
> suggestion of i386_cygwin_init_abi; but Corinna's earlier patches
> changed all Windows targets, not just Cygwin, and I didn't see a good
> place to do that.

Me neither.  There seems to be no i386_windows_init_abi which would
allow to define this for all Windows targets.

Btw., in contrast to Cygwin, native Windows hosts don't have the
nl_langinfo function.  Of course, this affects the default host charset.
ISO-8859-1 is no sensible default, even if it mostly works on western
language Windows systems since it's quite similar to CP1252.  The most
sensible default host charset for a native Windows GDB is the codepage
returned by GetACP(), as Eli already pointed out for the target charset.

Maybe something along these lines would help (untested!):

--- charset.c   2010-03-03 11:09:43.000000000 +0100
+++ charset.c.new       2010-03-03 11:09:36.000000000 +0100
@@ -904,6 +904,10 @@ default_auto_wide_charset (void)
   return GDB_DEFAULT_TARGET_WIDE_CHARSET;
 }
 
+#ifdef _WIN32
+static w32_host_default_charset[16]; /* "CP + x<=5 digits + paranoia. */
+#endif
+
 void
 _initialize_charset (void)
 {
@@ -927,6 +931,11 @@ _initialize_charset (void)
   if (!strcmp (auto_host_charset_name, "646") || !*auto_host_charset_name)
     auto_host_charset_name = "ASCII";
   auto_target_charset_name = auto_host_charset_name;
+#elif defined (_WIN32)
+  snprintf (w32_host_default_charset, sizeof w32_host_default_charset,
+           "CP%d", GetACP());
+  auto_host_charset_name = w32_host_default_charset;
+  auto_target_charset_name = auto_host_charset_name;
 #endif
 #endif
 

Corinna

-- 
Corinna Vinschen
Cygwin Project Co-Leader
Red Hat