put previously global error handling and key hashes into ptx (pcp context) to make libpcp threadsafe.

bindings/cpp/ptx.cpp

@@ -0,0 +1,34 @@
+/*
+    This file is part of Pretty Curved Privacy (pcp1).
+
+    Copyright (C) 2013 T.Linden.
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+    You can contact me by mail: <tlinden AT cpan DOT org>.
+*/
+
+#include "pcp++.h"
+
+using namespace std;
+using namespace pcp;
+
+PcpContext::PcpContext() {
+  ptx = ptx_new();
+}
+
+PcpContext::~PcpContext() {
+  ptx_clean(ptx);
+}
+