src: Refactoring common.hpp and minimizing exposed includes

Face class has relatively large rewrite to hide internals using
Implementor pattern.  As of this commit, <boost/asio.hpp> is not
automatically included whenever ndn-cxx/face.hpp is included.  If it is
needed to directly work with io_service, asio.hpp should be specifically
included.

Change-Id: Ie742b851025b4e3da634eb981319df0f42937855
diff --git a/src/interest-filter.cpp b/src/interest-filter.cpp
new file mode 100644
index 0000000..1f4f3fb
--- /dev/null
+++ b/src/interest-filter.cpp
@@ -0,0 +1,58 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/**
+ * Copyright (c) 2013-2014,  Regents of the University of California.
+ * All rights reserved.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ *
+ * This file licensed under New BSD License.  See COPYING for detailed information about
+ * ndn-cxx library copyright, permissions, and redistribution restrictions.
+ */
+
+#include "interest-filter.hpp"
+
+#include "util/regex/regex-pattern-list-matcher.hpp"
+
+namespace ndn {
+
+InterestFilter::InterestFilter(const Name& prefix, const std::string& regexFilter)
+  : m_prefix(prefix)
+  , m_regexFilter(ndn::make_shared<RegexPatternListMatcher>(regexFilter,
+                                                            shared_ptr<RegexBackrefManager>()))
+{
+}
+
+bool
+InterestFilter::doesMatch(const Name& name) const
+{
+  if (name.size() < m_prefix.size())
+    return false;
+
+  if (hasRegexFilter()) {
+    // perform prefix match and regular expression match for the remaining components
+    bool isMatch = m_prefix.isPrefixOf(name);
+
+    if (!isMatch)
+      return false;
+
+    return m_regexFilter->match(name, m_prefix.size(), name.size() - m_prefix.size());
+  }
+  else {
+    // perform just prefix match
+
+    return m_prefix.isPrefixOf(name);
+  }
+}
+
+std::ostream&
+operator<<(std::ostream& os, const InterestFilter& filter)
+{
+  os << filter.getPrefix();
+  if (filter.hasRegexFilter()) {
+    os << "?regex=" << filter.getRegexFilter();
+  }
+  return os;
+}
+
+} // namespace ndn