fix for bug #29 (blank lines in GetLineText)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@6272 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/textctrl.cpp

@@ -807,7 +807,16 @@ int wxTextCtrl::GetLineLength(long lineNo) const
 
 wxString wxTextCtrl::GetLineText(long lineNo) const
 {
+    // TODO this should probably be optimized by using GetWriteBuf()
+
     size_t len = (size_t)GetLineLength(lineNo) + 1;
+    if ( len < sizeof(WORD) )
+    {
+        // there must be at least enough place for the length WORD in the
+        // buffer
+        len += sizeof(WORD);
+    }
+
     char *buf = (char *)malloc(len);
     *(WORD *)buf = len;
     int noChars = (int)SendMessage(GetHwnd(), EM_GETLINE, lineNo, (LPARAM)buf);