common/: add tracked_int_ptr.hpp

TrackedIntPtr acts like intrusive_ptr, but is able to
track a ref id.

Signed-off-by: Samuel Just <sam.just@inktank.com>

2 files changed, 68 insertions, 0 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index d528b78a1be..cd360fcd147 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1601,6 +1601,7 @@ noinst_HEADERS = \
 	common/admin_socket.h \
 	common/admin_socket_client.h \
 	common/shared_cache.hpp \
+	common/tracked_int_ptr.hpp \
 	common/simple_cache.hpp \
 	common/sharedptr_registry.hpp \
 	common/map_cacher.hpp \
diff --git a/src/common/tracked_int_ptr.hpp b/src/common/tracked_int_ptr.hpp
new file mode 100644
index 00000000000..ba0900db6bd
--- /dev/null
+++ b/src/common/tracked_int_ptr.hpp
@@ -0,0 +1,67 @@
+// -*- 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) 2013 Inktank Storage, Inc.
+ *
+ * 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_TRACKEDINTPTR_H
+#define CEPH_TRACKEDINTPTR_H
+
+#include <map>
+#include <list>
+#include <memory>
+#include <utility>
+#include "common/Mutex.h"
+#include "common/Cond.h"
+
+template <class T>
+class TrackedIntPtr {
+  T *ptr;
+  uint64_t id;
+public:
+  TrackedIntPtr() : ptr(NULL), id(0) {}
+  TrackedIntPtr(T *ptr) : ptr(ptr), id(ptr ? get_with_id(ptr) : 0) {}
+  ~TrackedIntPtr() {
+    if (ptr)
+      put_with_id(ptr, id);
+    else
+      assert(id == 0);
+  }
+  void swap(TrackedIntPtr &other) {
+    T *optr = other.ptr;
+    uint64_t oid = other.id;
+    other.ptr = ptr;
+    other.id = id;
+    ptr = optr;
+    id = oid;
+  }
+  TrackedIntPtr(const TrackedIntPtr &rhs) :
+    ptr(rhs.ptr), id(ptr ? get_with_id(ptr) : 0) {}
+
+  void operator=(const TrackedIntPtr &rhs) {
+    TrackedIntPtr o(rhs.ptr);
+    swap(o);
+  }
+  T &operator*() {
+    return *ptr;
+  }
+  T *operator->() {
+    return ptr;
+  }
+  bool operator<(const TrackedIntPtr &lhs) const {
+    return ptr < lhs.ptr;
+  }
+  bool operator==(const TrackedIntPtr &lhs) const {
+    return ptr == lhs.ptr;
+  }
+};
+
+#endif