avoid undefined behavior from token paste resulting in more than one token

[wxWidgets.git] / src / common / sysopt.cpp

diff --git a/src/common/sysopt.cpp b/src/common/sysopt.cpp
index cb3c3429bbc6f7bc7b63de8a2b6971d412ac5de3..56227995c9edb0db31ea296cceddd7c61d1f258f 100644 (file)
--- a/src/common/sysopt.cpp
+++ b/src/common/sysopt.cpp
@@ -29,6 +29,7 @@
 #include "wx/sysopt.h"
 
 #ifndef WX_PRECOMP
+    #include "wx/app.h"
     #include "wx/list.h"
     #include "wx/string.h"
     #include "wx/arrstr.h"
@@ -68,11 +69,33 @@ void wxSystemOptions::SetOption(const wxString& name, int value)
 
 wxString wxSystemOptions::GetOption(const wxString& name)
 {
+    wxString val;
+
     int idx = gs_optionNames.Index(name, false);
-    if (idx == wxNOT_FOUND)
-        return wxEmptyString;
-    else
-        return gs_optionValues[idx];
+    if ( idx != wxNOT_FOUND )
+    {
+        val = gs_optionValues[idx];
+    }
+    else // not set explicitely
+    {
+        // look in the environment: first for a variable named "wx_appname_name"
+        // which can be set to affect the behaviour or just this application
+        // and then for "wx_name" which can be set to change the option globally
+        wxString var(name);
+        var.Replace(_T("."), _T("_"));  // '.'s not allowed in env var names
+
+        wxString appname;
+        if ( wxTheApp )
+            appname = wxTheApp->GetAppName();
+
+        if ( !appname.empty() )
+            val = wxGetenv(_T("wx_") + appname + _T('_') + var);
+
+        if ( val.empty() )
+            val = wxGetenv(_T("wx_") + var);
+    }
+
+    return val;
 }
 
 int wxSystemOptions::GetOptionInt(const wxString& name)
@@ -82,7 +105,7 @@ int wxSystemOptions::GetOptionInt(const wxString& name)
 
 bool wxSystemOptions::HasOption(const wxString& name)
 {
-    return gs_optionNames.Index(name, false) != wxNOT_FOUND;
+    return !GetOption(name).empty();
 }
 
 #endif // wxUSE_SYSTEM_OPTIONS