Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 100 insertions, 0 deletions

diff --git a/src/mgr/TTLCache.cc b/src/mgr/TTLCache.cc
new file mode 100644
index 000000000..05fe95987
--- /dev/null
+++ b/src/mgr/TTLCache.cc
@@ -0,0 +1,100 @@
+#include "TTLCache.h"
+
+#include <chrono>
+#include <functional>
+#include <string>
+
+#include "PyUtil.h"
+
+template <class Key, class Value>
+void TTLCacheBase<Key, Value>::insert(Key key, Value value) {
+  auto now = std::chrono::steady_clock::now();
+
+  if (!ttl) return;
+  int16_t random_ttl_offset =
+      ttl * ttl_spread_ratio * (2l * rand() / float(RAND_MAX) - 1);
+  // in order not to have spikes of misses we increase or decrease by 25% of
+  // the ttl
+  int16_t spreaded_ttl = ttl + random_ttl_offset;
+  auto expiration_date = now + std::chrono::seconds(spreaded_ttl);
+  cache::insert(key, {value, expiration_date});
+}
+
+template <class Key, class Value> Value TTLCacheBase<Key, Value>::get(Key key) {
+  if (!exists(key)) {
+    throw_key_not_found(key);
+  }
+  if (expired(key)) {
+    erase(key);
+    throw_key_not_found(key);
+  }
+  Value value = {get_value(key)};
+  return value;
+}
+
+template <class Key> PyObject* TTLCache<Key, PyObject*>::get(Key key) {
+  if (!this->exists(key)) {
+    this->throw_key_not_found(key);
+  }
+  if (this->expired(key)) {
+    this->erase(key);
+    this->throw_key_not_found(key);
+  }
+  PyObject* cached_value = this->get_value(key);
+  Py_INCREF(cached_value);
+  return cached_value;
+}
+
+template <class Key, class Value>
+void TTLCacheBase<Key, Value>::erase(Key key) {
+  cache::erase(key);
+}
+
+template <class Key> void TTLCache<Key, PyObject*>::erase(Key key) {
+  Py_DECREF(this->get_value(key, false));
+  ttl_base::erase(key);
+}
+
+template <class Key, class Value>
+bool TTLCacheBase<Key, Value>::expired(Key key) {
+  ttl_time_point expiration_date = get_value_time_point(key);
+  auto now = std::chrono::steady_clock::now();
+  if (now >= expiration_date) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+template <class Key, class Value> void TTLCacheBase<Key, Value>::clear() {
+  cache::clear();
+}
+
+template <class Key, class Value>
+Value TTLCacheBase<Key, Value>::get_value(Key key, bool count_hit) {
+  value_type stored_value = cache::get(key, count_hit);
+  Value value = std::get<0>(stored_value);
+  return value;
+}
+
+template <class Key, class Value>
+ttl_time_point TTLCacheBase<Key, Value>::get_value_time_point(Key key) {
+  value_type stored_value = cache::get(key, false);
+  ttl_time_point tp = std::get<1>(stored_value);
+  return tp;
+}
+
+template <class Key, class Value>
+void TTLCacheBase<Key, Value>::set_ttl(uint16_t ttl) {
+  this->ttl = ttl;
+}
+
+template <class Key, class Value>
+bool TTLCacheBase<Key, Value>::exists(Key key) {
+  return cache::exists(key);
+}
+
+template <class Key, class Value>
+void TTLCacheBase<Key, Value>::throw_key_not_found(Key key) {
+  cache::throw_key_not_found(key);
+}