1 files changed, 115 insertions, 0 deletions
diff --git a/src/log/Entry.h b/src/log/Entry.h
new file mode 100644
index 00000000..536f1a9d
--- /dev/null
+++ b/src/log/Entry.h
@@ -0,0 +1,115 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#ifndef __CEPH_LOG_ENTRY_H
+#define __CEPH_LOG_ENTRY_H
+
+#include "log/LogClock.h"
+
+#include "common/StackStringStream.h"
+
+#include "boost/container/small_vector.hpp"
+
+#include <pthread.h>
+
+#include <string_view>
+
+namespace ceph {
+namespace logging {
+
+class Entry {
+public:
+  using time = log_time;
+
+  Entry() = delete;
+  Entry(short pr, short sub) :
+    m_stamp(clock().now()),
+    m_thread(pthread_self()),
+    m_prio(pr),
+    m_subsys(sub)
+  {}
+  Entry(const Entry &) = default;
+  Entry& operator=(const Entry &) = default;
+  Entry(Entry &&e) = default;
+  Entry& operator=(Entry &&e) = default;
+  virtual ~Entry() = default;
+
+  virtual std::string_view strv() const = 0;
+  virtual std::size_t size() const = 0;
+
+  time m_stamp;
+  pthread_t m_thread;
+  short m_prio, m_subsys;
+
+  static log_clock& clock() {
+    static log_clock clock;
+    return clock;
+  }
+};
+
+/* This should never be moved to the heap! Only allocate this on the stack. See
+ * CachedStackStringStream for rationale.
+ */
+class MutableEntry : public Entry {
+public:
+  MutableEntry() = delete;
+  MutableEntry(short pr, short sub) : Entry(pr, sub) {}
+  MutableEntry(const MutableEntry&) = delete;
+  MutableEntry& operator=(const MutableEntry&) = delete;
+  MutableEntry(MutableEntry&&) = delete;
+  MutableEntry& operator=(MutableEntry&&) = delete;
+  ~MutableEntry() override = default;
+
+  std::ostream& get_ostream() {
+    return *cos;
+  }
+
+  std::string_view strv() const override {
+    return cos->strv();
+  }
+  std::size_t size() const override {
+    return cos->strv().size();
+  }
+
+private:
+  CachedStackStringStream cos;
+};
+
+class ConcreteEntry : public Entry {
+public:
+  ConcreteEntry() = delete;
+  ConcreteEntry(const Entry& e) : Entry(e) {
+    auto strv = e.strv();
+    str.reserve(strv.size());
+    str.insert(str.end(), strv.begin(), strv.end());
+  }
+  ConcreteEntry& operator=(const Entry& e) {
+    Entry::operator=(e);
+    auto strv = e.strv();
+    str.reserve(strv.size());
+    str.assign(strv.begin(), strv.end());
+    return *this;
+  }
+  ConcreteEntry(ConcreteEntry&& e) : Entry(e), str(std::move(e.str)) {}
+  ConcreteEntry& operator=(ConcreteEntry&& e) {
+    Entry::operator=(e);
+    str = std::move(e.str);
+    return *this;
+  }
+  ~ConcreteEntry() override = default;
+
+  std::string_view strv() const override {
+    return std::string_view(str.data(), str.size());
+  }
+  std::size_t size() const override {
+    return str.size();
+  }
+
+private:
+  boost::container::small_vector<char, 1024> str;
+};
+
+}
+}
+
+#endif