Add vsprintf method to QString

src/tools/qstring.cpp

@@ -4,6 +4,7 @@
 **
 ** Created : 920722
 **
+** Copyright (C) 2015 Timothy Pearson. All rights reserved.
 ** Copyright (C) 1992-2008 Trolltech ASA.  All rights reserved.
 **
 ** This file is part of the tools module of the Qt GUI Toolkit.
@@ -2604,12 +2605,10 @@ QString QString::multiArg( int numArgs, const QString& a1, const QString& a2,
 */
 
 #ifndef QT_NO_SPRINTF
-QString &QString::sprintf( const char* cformat, ... )
+QString &QString::sprintf(const char *cformat, ...)
 {
-    QLocale locale(QLocale::C);
-
     va_list ap;
-    va_start( ap, cformat );
+    va_start(ap, cformat);
 
     if ( !cformat || !*cformat ) {
 	// Qt 1.x compat
@@ -2617,6 +2616,16 @@ QString &QString::sprintf( const char* cformat, ... )
 	return *this;
     }
 
+    QString &s = vsprintf(cformat, ap);
+
+    va_end(ap);
+    return s;
+}
+
+QString &QString::vsprintf( const char* cformat, va_list ap )
+{
+    QLocale locale(QLocale::C);
+
     // Parse cformat
 
     QString result;
@@ -2933,7 +2942,6 @@ QString &QString::sprintf( const char* cformat, ... )
 	    result.append(subst.rightJustify(width));
     }
 
-    va_end(ap);
     *this = result;
 
     return *this;

src/tools/qstring.h

@@ -4,6 +4,7 @@
 **
 ** Created : 920609
 **
+** Copyright (C) 2015 Timothy Pearson. All rights reserved.
 ** Copyright (C) 1992-2008 Trolltech ASA.  All rights reserved.
 **
 ** This file is part of the tools module of the Qt GUI Toolkit.
@@ -63,6 +64,9 @@
 #endif
 #endif
 
+#ifndef QT_NO_SPRINTF
+#include <stdarg.h>
+#endif
 
 /*****************************************************************************
   QString class
@@ -452,6 +456,11 @@ public:
     QString    &sprintf( const char* format, ... )
 #if defined(Q_CC_GNU) && !defined(__INSURE__)
         __attribute__ ((format (printf, 2, 3)))
+#endif
+        ;
+    QString    &vsprintf(const char *format, va_list ap)
+#if defined(Q_CC_GNU) && !defined(__INSURE__)
+        __attribute__ ((format (printf, 2, 0)))
 #endif
         ;
 #endif