msvcrt: Fix *printf() handling of negative field width.

dlls/msvcrt/tests/printf.c

@@ -279,6 +279,11 @@ static void test_sprintf( void )
     ok(!strcmp(buffer,"f"),"Precision ignored \"%s\"\n",buffer);
     ok( r==1, "return count wrong\n");
 
+    format = "%*s";
+    r = sprintf(buffer,format,-5,"foo");
+    ok(!strcmp(buffer,"foo  "),"Negative field width ignored \"%s\"\n",buffer);
+    ok( r==5, "return count wrong\n");
+
     format = "%#-012p";
     r = sprintf(buffer,format,(void *)57);
     ok(!strcmp(buffer,"0X00000039  "),"Pointer formatted incorrectly\n");

dlls/msvcrt/wcs.c

@@ -568,9 +568,14 @@ static int pf_vsnprintf( pf_output *out, const WCHAR *format, va_list valist )
 
         /* deal with the field width specifier */
         flags.FieldLength = 0;
-        if( *p == '*' ) 
+        if( *p == '*' )
         {
             flags.FieldLength = va_arg( valist, int );
+            if (flags.FieldLength < 0)
+            {
+                flags.LeftAlign = '-';
+                flags.FieldLength = -flags.FieldLength;
+            }
             p++;
         }
         else while( isdigit(*p) )