include: Cast-qual warnings fix using const_cast macro

[Andrew Talbot]

This patch may not get applied, but it does allow one to see a truer picture
of the remaining cast-qual warning violations, by removing the distortion
caused by some of the inlined functions in "unicode.h".

-- Andy.
---
Changelog:
    include: Cast-qual warnings fix using const_cast macro.

diff -urN a/include/wine/unicode.h b/include/wine/unicode.h
--- a/include/wine/unicode.h	2006-12-16 10:33:52.000000000 +0000
+++ b/include/wine/unicode.h	2006-12-14 22:39:43.000000000 +0000
@@ -35,6 +35,12 @@
 #define WINE_UNICODE_API DECLSPEC_IMPORT
 #endif
 
+#ifdef __cplusplus
+#define const_cast(t, e)    const_cast<t>(e)
+#else
+#define const_cast(t, e)    (t)(ULONG_PTR)(e)
+#endif
+
 /* code page info common to SBCS and DBCS */
 struct cp_info
 {
@@ -240,7 +246,7 @@
 extern inline WCHAR *strchrW( const WCHAR *str, WCHAR ch );
 extern inline WCHAR *strchrW( const WCHAR *str, WCHAR ch )
 {
-    do { if (*str == ch) return (WCHAR *)str; } while (*str++);
+    do { if (*str == ch) return const_cast(WCHAR *, str); } while (*str++);
     return NULL;
 }
 
@@ -248,14 +254,14 @@
 extern inline WCHAR *strrchrW( const WCHAR *str, WCHAR ch )
 {
     WCHAR *ret = NULL;
-    do { if (*str == ch) ret = (WCHAR *)str; } while (*str++);
+    do { if (*str == ch) ret = const_cast(WCHAR *, str); } while (*str++);
     return ret;
 }
 
 extern inline WCHAR *strpbrkW( const WCHAR *str, const WCHAR *accept );
 extern inline WCHAR *strpbrkW( const WCHAR *str, const WCHAR *accept )
 {
-    for ( ; *str; str++) if (strchrW( accept, *str )) return (WCHAR *)str;
+    for ( ; *str; str++) if (strchrW( accept, *str )) return const_cast(WCHAR *, str);
     return NULL;
 }
 
@@ -295,7 +301,7 @@
 extern inline WCHAR *memchrW( const WCHAR *ptr, WCHAR ch, size_t n )
 {
     const WCHAR *end;
-    for (end = ptr + n; ptr < end; ptr++) if (*ptr == ch) return (WCHAR *)ptr;
+    for (end = ptr + n; ptr < end; ptr++) if (*ptr == ch) return const_cast(WCHAR *, ptr);
     return NULL;
 }
 
@@ -304,7 +310,7 @@
 {
     const WCHAR *end, *ret = NULL;
     for (end = ptr + n; ptr < end; ptr++) if (*ptr == ch) ret = ptr;
-    return (WCHAR *)ret;
+    return const_cast(WCHAR *, ret);
 }
 
 extern inline long int atolW( const WCHAR *str );