fix possible race condition in Normalizer cache

src/pfaedle/trgraph/Normalizer.cpp

@@ -3,7 +3,9 @@
 // Authors: Patrick Brosi <brosi@informatik.uni-freiburg.de>
 
 #include <algorithm>
+#include <cassert>
 #include <iostream>
+#include <mutex>
 #include <regex>
 #include <sstream>
 #include <stdexcept>
@@ -15,12 +17,39 @@
 using pfaedle::trgraph::Normalizer;
 
 // _____________________________________________________________________________
-Normalizer::Normalizer(const ReplRules& rules) : _rulesOrig(rules) {
+Normalizer::Normalizer(const ReplRules& rules)
+    : _rulesOrig(rules) {
   buildRules(rules);
 }
 
+// _____________________________________________________________________________
+Normalizer::Normalizer(const Normalizer& other)
+    : _rules(other._rules),
+      _rulesOrig(other._rulesOrig),
+      _cache(other._cache) {}
+
+// _____________________________________________________________________________
+Normalizer& Normalizer::operator=(Normalizer other) {
+  std::swap(this->_rules, other._rules);
+  std::swap(this->_rulesOrig, other._rulesOrig);
+  std::swap(this->_cache, other._cache);
+
+  return *this;
+}
+
 // _____________________________________________________________________________
 std::string Normalizer::operator()(std::string sn) const {
+  return normTS(sn);
+}
+
+// _____________________________________________________________________________
+std::string Normalizer::normTS(const std::string& sn) const {
+  std::lock_guard<std::mutex> lock(_mutex);
+  return norm(sn);
+}
+
+// _____________________________________________________________________________
+std::string Normalizer::norm(const std::string& sn) const {
   auto i = _cache.find(sn);
   if (i != _cache.end()) return i->second;
 

src/pfaedle/trgraph/Normalizer.h

@@ -10,6 +10,7 @@
 #include <unordered_map>
 #include <utility>
 #include <vector>
+#include <mutex>
 
 namespace pfaedle {
 namespace trgraph {
@@ -28,7 +29,19 @@ class Normalizer {
   Normalizer() {}
   explicit Normalizer(const ReplRules& rules);
 
-  // Normalize sn based on the rules of this normalizer
+  // copy constructor
+  Normalizer(const Normalizer& other);
+
+  // assignment op
+  Normalizer& operator=(Normalizer other);
+
+  // Normalize sn, not thread safe
+  std::string norm(const std::string& sn) const;
+  // Normalize sn, thread safe
+  std::string normTS(const std::string& sn) const;
+
+  // Normalize sn based on the rules of this normalizer, uses the thread safe
+  // version of norm() internally
   std::string operator()(std::string sn) const;
   bool operator==(const Normalizer& b) const;
 
@@ -36,6 +49,7 @@ class Normalizer {
   ReplRulesComp _rules;
   ReplRules _rulesOrig;
   mutable std::unordered_map<std::string, std::string> _cache;
+  mutable std::mutex _mutex;
 
   void buildRules(const ReplRules& rules);
 };

src/pfaedle/trgraph/StatGroup.cpp

@@ -68,7 +68,7 @@ double StatGroup::getPen(const Stop* s, trgraph::Node* n,
   double distPen = util::geo::webMercMeterDist(p, *n->pl().getGeom());
   distPen *= distPenFac;
 
-  std::string platform = platformNorm(s->getPlatformCode());
+  std::string platform = platformNorm.norm(s->getPlatformCode());
 
   if (!platform.empty() && !n->pl().getSI()->getTrack().empty() &&
       n->pl().getSI()->getTrack() == platform) {