Adding nsync for NLSR
diff --git a/nsync/src/sync-digest.h b/nsync/src/sync-digest.h
new file mode 100644
index 0000000..ecc8522
--- /dev/null
+++ b/nsync/src/sync-digest.h
@@ -0,0 +1,199 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2012 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ * Chaoyi Bian <bcy@pku.edu.cn>
+ * Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef SYNC_DIGEST_H
+#define SYNC_DIGEST_H
+
+#include <boost/exception/all.hpp>
+#include <openssl/evp.h>
+#include <boost/cstdint.hpp>
+#include <vector>
+
+namespace Sync {
+
+/**
+ * @ingroup sync
+ * @brief A simple wrapper for libcrypto hash functions
+ */
+class Digest
+{
+public:
+ /**
+ * @brief Default constructor. Will initialize internal libssl structures
+ */
+ Digest ();
+
+ /**
+ * @brief Check if digest is empty
+ */
+ bool
+ empty () const;
+
+ /**
+ * @brief Reset digest to the initial state
+ */
+ void
+ reset ();
+
+ /**
+ * @brief Destructor
+ */
+ ~Digest ();
+
+ /**
+ * @brief Obtain a short version of the hash (just first sizeof(size_t) bytes
+ *
+ * Side effect: finalize() will be called on `this'
+ */
+ std::size_t
+ getHash () const;
+
+ /**
+ * @brief Finalize digest. All subsequent calls to "operator <<" will fire an exception
+ */
+ void
+ finalize ();
+
+ /**
+ * @brief Compare two full digests
+ *
+ * Side effect: Finalize will be called on `this' and `digest'
+ */
+ bool
+ operator == (const Digest &digest) const;
+
+ bool
+ operator != (const Digest &digest) const
+ { return ! (*this == digest); }
+
+
+ /**
+ * @brief Add existing digest to digest calculation
+ * @param src digest to combine with
+ *
+ * The result of this combination is hash (hash (...))
+ */
+ Digest &
+ operator << (const Digest &src);
+
+ /**
+ * @brief Add string to digest calculation
+ * @param str string to put into digest
+ */
+ inline Digest &
+ operator << (const std::string &str);
+
+ /**
+ * @brief Add uint64_t value to digest calculation
+ * @param value uint64_t value to put into digest
+ */
+ inline Digest &
+ operator << (uint64_t value);
+
+ /**
+ * @brief Checks if the stored hash is zero-root hash
+ *
+ * Zero-root hash is a valid hash that optimally represents an empty state
+ */
+ bool
+ isZero () const;
+
+private:
+ Digest &
+ operator = (Digest &digest) { (void)digest; return *this; }
+
+ /**
+ * @brief Add size bytes of buffer to the hash
+ */
+ void
+ update (const uint8_t *buffer, size_t size);
+
+ friend std::ostream &
+ operator << (std::ostream &os, const Digest &digest);
+
+ friend std::istream &
+ operator >> (std::istream &is, Digest &digest);
+
+private:
+ EVP_MD_CTX *m_context;
+ std::vector<uint8_t> m_buffer;
+};
+
+namespace Error {
+struct DigestCalculationError : virtual boost::exception, virtual std::exception { };
+}
+
+typedef boost::shared_ptr<Digest> DigestPtr;
+typedef boost::shared_ptr<const Digest> DigestConstPtr;
+
+Digest &
+Digest::operator << (const std::string &str)
+{
+ update (reinterpret_cast<const uint8_t*> (str.c_str ()), str.size ());
+ return *this;
+}
+
+inline Digest &
+Digest::operator << (uint64_t value)
+{
+ update (reinterpret_cast<const uint8_t*> (&value), sizeof (uint64_t));
+ return *this;
+}
+
+std::ostream &
+operator << (std::ostream &os, const Digest &digest);
+
+std::istream &
+operator >> (std::istream &is, Digest &digest);
+
+// template<class INT>
+// Digest &
+// Digest::operator << (INT value)
+// {
+// update (&value, sizeof (INT));
+// return *this;
+// }
+
+struct DigestPtrHash : public std::unary_function<Digest, std::size_t>
+{
+ std::size_t
+ operator() (DigestConstPtr digest) const
+ {
+ // std::cout << "digest->getHash: " << digest->getHash () << " (" << *digest << ")" << std::endl;
+ return digest->getHash ();
+ }
+};
+
+struct DigestPtrEqual : public std::unary_function<Digest, std::size_t>
+{
+ bool
+ operator() (DigestConstPtr digest1, DigestConstPtr digest2) const
+ {
+ // std::cout << boost::cref(*digest1) << " == " << boost::cref(*digest2) << " : " << (*digest1 == *digest2) << std::endl;
+ return *digest1 == *digest2;
+ }
+};
+
+
+} // Sync
+
+#endif // SYNC_DIGEST_H