Fixed zlib build for WEC7.

errno in zutil.c is leftover, and not used anymore -> removed.

In gzguts.h qfunctions_wince.h are included. To use this header
qglobal.h is needed.

In qfunctions_wince.h a special define section is added for
zlib.

Task-number: QTBUG-22507
Change-Id: I78ec78d22e2930a03b349a47ab3a3ad077277c42
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>

src/3rdparty/zlib/gzguts.h

@@ -33,6 +33,9 @@
 #endif
 #if !defined(_WIN32_WCE)
 #  include <fcntl.h>
+#else
+# include <qglobal.h>
+# include <qfunctions_wince.h>
 #endif
 
 #ifdef NO_DEFLATE       /* for compatibility with old definition */
@@ -40,7 +43,9 @@
 #endif
 
 #ifdef _MSC_VER
+#  if !defined(_WIN32_WCE)
 #    include <io.h>
+#  endif
 #  define vsnprintf _vsnprintf
 #endif
 

src/3rdparty/zlib/zutil.c

@@ -136,14 +136,6 @@ const char * ZEXPORT zError(err)
     return ERR_MSG(err);
 }
 
-#if defined(_WIN32_WCE)
-    /* The Microsoft C Run-Time Library for Windows CE doesn't have
-     * errno.  We define it as a global variable to simplify porting.
-     * Its value is always 0 and should not be used.
-     */
-    int errno = 0;
-#endif
-
 #ifndef HAVE_MEMCPY
 
 void ZLIB_INTERNAL zmemcpy(dest, source, len)

src/corelib/kernel/qfunctions_wince.h

@@ -182,6 +182,16 @@ void    qt_wince_rewind( FILE *stream );
 int     qt_wince___fileno(FILE *);
 FILE   *qt_wince_tmpfile( void );
 
+//For zlib we need these helper functions, but they break the build when
+//set globally, so just set them for zlib use
+#ifdef ZLIB_H
+#define open qt_wince_open
+#define close qt_wince__close
+#define lseek qt_wince__lseek
+#define read qt_wince__read
+#define write qt_wince__write
+#endif
+
 int qt_wince__mkdir(const char *dirname);
 int qt_wince__rmdir(const char *dirname);
 int qt_wince__access( const char *path, int pmode );