X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fwctype.in.h;h=835185f46fc5d0f4dd7061d3f2baa365b9637f1a;hb=9b1723bc19a2770a3f57e6432347dab683e2f027;hp=66e095a37404d428ccaf990a449586a8a5283293;hpb=819bc00dda799634ce12f28d82642706e13389aa;p=gnulib.git

diff --git a/lib/wctype.in.h b/lib/wctype.in.h
index 66e095a37..835185f46 100644
--- a/lib/wctype.in.h
+++ b/lib/wctype.in.h
@@ -196,5 +196,36 @@ towupper (wint_t wc)
 
 # endif /* ! HAVE_ISWCNTRL */
 
+# if defined __MINGW32__
+
+/* On native Windows, wchar_t is uint16_t, and wint_t is uint32_t.
+   The functions towlower and towupper are implemented in the MSVCRT library
+   to take a wchar_t argument and return a wchar_t result.  mingw declares
+   these functions to take a wint_t argument and return a wint_t result.
+   This means that:
+   1. When the user passes an argument outside the range 0x0000..0xFFFF, the
+      function will look only at the lower 16 bits.  This is allowed according
+      to POSIX.
+   2. The return value is returned in the lower 16 bits of the result register.
+      The upper 16 bits are random: whatever happened to be in that part of the
+      result register.  We need to fix this by adding a zero-extend from
+      wchar_t to wint_t after the call.  */
+
+static inline wint_t
+rpl_towlower (wint_t wc)
+{
+  return (wint_t) (wchar_t) towlower (wc);
+}
+#  define towlower rpl_towlower
+
+static inline wint_t
+rpl_towupper (wint_t wc)
+{
+  return (wint_t) (wchar_t) towupper (wc);
+}
+#  define towupper rpl_towupper
+
+# endif
+
 #endif /* _GL_WCTYPE_H */
 #endif /* _GL_WCTYPE_H */