convert kademlia example to s4u

[simgrid.git] / examples / s4u / dht-kademlia / answer.cpp

diff --git a/examples/s4u/dht-kademlia/answer.cpp b/examples/s4u/dht-kademlia/answer.cpp
new file mode 100644 (file)
index 0000000..48ee12b
--- /dev/null
+++ b/examples/s4u/dht-kademlia/answer.cpp
@@ -0,0 +1,82 @@
+/* Copyright (c) 2012-2014, 2016-2017. The SimGrid Team.
+ * All rights reserved.                                                     */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "answer.hpp"
+
+XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(kademlia_node);
+
+namespace kademlia {
+
+bool sortbydistance(const std::pair<unsigned int, unsigned int>& a, const std::pair<unsigned int, unsigned int>& b)
+{
+  return (a.second < b.second);
+}
+
+/** @brief Prints a answer_t, for debugging purposes */
+void Answer::print()
+{
+  XBT_INFO("Searching %08x, size %u", destination_id_, size_);
+  unsigned int i = 0;
+  for (auto contact : nodes)
+    XBT_INFO("Node %08x: %08x is at distance %u", i++, contact.first, contact.second);
+}
+
+/** @brief Merge two answers together, only keeping the best nodes
+  * @param source the source of the nodes to add
+  */
+unsigned int Answer::merge(Answer* source)
+{
+  if (this == source)
+    return 0;
+
+  unsigned int nb_added = 0;
+  for (auto contact : source->nodes) {
+    if (std::find(nodes.begin(), nodes.end(), contact) == nodes.end()) {
+      nodes.push_back(contact);
+      size_++;
+      nb_added++;
+    }
+  }
+  std::sort(nodes.begin(), nodes.end(), sortbydistance);
+  trim();
+  return nb_added;
+}
+
+/** @brief Trims an Answer, in order for it to have a size of less or equal to "bucket_size" */
+void Answer::trim()
+{
+  while (size_ > BUCKET_SIZE) {
+    nodes.pop_back();
+    size_--;
+  }
+  xbt_assert(nodes.size() == size_, "Wrong size for the answer");
+}
+
+/** @brief Returns if the destination we are trying to find is found
+  * @return if the destination is found.
+  */
+bool Answer::destinationFound()
+{
+  if (nodes.empty())
+    return 0;
+
+  return (*nodes.begin()).second == 0;
+}
+
+/** @brief Adds the content of a bucket unsigned into a answer object.
+  * @param bucket the bucket we have to had unsigned into
+  */
+void Answer::addBucket(Bucket* bucket)
+{
+  xbt_assert((bucket != nullptr), "Provided a NULL bucket");
+
+  for (auto id : bucket->nodes) {
+    unsigned int distance = id ^ destination_id_;
+    nodes.push_back(std::pair<unsigned int, unsigned int>(id, distance));
+    size_++;
+  }
+}
+}