1 files changed, 132 insertions, 0 deletions
diff --git a/src/mds/LogEvent.h b/src/mds/LogEvent.h
new file mode 100644
index 00000000..7c7273f8
--- /dev/null
+++ b/src/mds/LogEvent.h
@@ -0,0 +1,132 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- 
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software 
+ * Foundation.  See file COPYING.
+ * 
+ */
+
+#ifndef CEPH_LOGEVENT_H
+#define CEPH_LOGEVENT_H
+
+#define EVENT_NEW_ENCODING 0 // indicates that the encoding is versioned
+#define EVENT_UNUSED       1 // was previously EVENT_STRING
+
+#define EVENT_SUBTREEMAP   2
+#define EVENT_EXPORT       3
+#define EVENT_IMPORTSTART  4
+#define EVENT_IMPORTFINISH 5
+#define EVENT_FRAGMENT     6
+
+#define EVENT_RESETJOURNAL 9
+
+#define EVENT_SESSION      10
+#define EVENT_SESSIONS_OLD 11
+#define EVENT_SESSIONS     12
+
+#define EVENT_UPDATE       20
+#define EVENT_SLAVEUPDATE  21
+#define EVENT_OPEN         22
+#define EVENT_COMMITTED    23
+
+#define EVENT_TABLECLIENT  42
+#define EVENT_TABLESERVER  43
+
+#define EVENT_SUBTREEMAP_TEST   50
+#define EVENT_NOOP        51
+
+
+#include "include/buffer_fwd.h"
+#include "include/Context.h"
+#include "include/utime.h"
+
+class MDSRank;
+class LogSegment;
+class EMetaBlob;
+
+// generic log event
+class LogEvent {
+public:
+  friend class MDLog;
+  typedef __u32 EventType;
+
+  LogEvent() = delete;
+  explicit LogEvent(int t) : _type(t) {}
+  LogEvent(const LogEvent&) = delete;
+  LogEvent& operator=(const LogEvent&) = delete;
+  virtual ~LogEvent() {}
+
+  std::string_view get_type_str() const;
+  static EventType str_to_type(std::string_view str);
+  EventType get_type() const { return _type; }
+  void set_type(EventType t) { _type = t; }
+
+  uint64_t get_start_off() const { return _start_off; }
+  void set_start_off(uint64_t o) { _start_off = o; }
+
+  utime_t get_stamp() const { return stamp; }
+  void set_stamp(utime_t t) { stamp = t; }
+
+  // encoding
+  virtual void encode(bufferlist& bl, uint64_t features) const = 0;
+  virtual void decode(bufferlist::const_iterator &) = 0;
+  static std::unique_ptr<LogEvent> decode_event(bufferlist::const_iterator);
+  virtual void dump(Formatter *f) const = 0;
+
+  void encode_with_header(bufferlist& bl, uint64_t features) {
+    using ceph::encode;
+    encode(EVENT_NEW_ENCODING, bl);
+    ENCODE_START(1, 1, bl)
+    encode(_type, bl);
+    this->encode(bl, features);
+    ENCODE_FINISH(bl);
+  }
+
+  virtual void print(ostream& out) const { 
+    out << "event(" << _type << ")";
+  }
+
+  /*** live journal ***/
+  /* update_segment() - adjust any state we need to in the LogSegment 
+   */
+  virtual void update_segment() { }
+
+  /*** recovery ***/
+  /* replay() - replay given event.  this is idempotent.
+   */
+  virtual void replay(MDSRank *m) { ceph_abort(); }
+
+  /**
+   * If the subclass embeds a MetaBlob, return it here so that
+   * tools can examine metablobs while traversing lists of LogEvent.
+   */
+  virtual EMetaBlob *get_metablob() { return NULL; }
+
+protected:
+  utime_t stamp;
+
+  LogSegment* get_segment() { return _segment; }
+  LogSegment const* get_segment() const { return _segment; }
+
+private:
+  static const std::map<std::string, LogEvent::EventType> types;
+
+  static std::unique_ptr<LogEvent> decode_event(bufferlist::const_iterator&, EventType);
+
+  EventType _type = 0;
+  uint64_t _start_off = 0;
+  LogSegment *_segment = nullptr;
+};
+
+inline ostream& operator<<(ostream& out, const LogEvent &le) {
+  le.print(out);
+  return out;
+}
+
+#endif