1 files changed, 383 insertions, 0 deletions
diff --git a/src/include/compact_map.h b/src/include/compact_map.h
new file mode 100644
index 000000000..21645e3d1
--- /dev/null
+++ b/src/include/compact_map.h
@@ -0,0 +1,383 @@
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2015 Red Hat, 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_COMPACT_MAP_H
+#define CEPH_COMPACT_MAP_H
+
+#include "buffer.h"
+#include "encoding.h"
+
+#include <map>
+#include <memory>
+
+#include "include/encoding.h"
+
+template <class Key, class T, class Map>
+class compact_map_base {
+protected:
+  std::unique_ptr<Map> map;
+  void alloc_internal() {
+    if (!map)
+      map.reset(new Map);
+  }
+  void free_internal() {
+    map.reset();
+  }
+  template <class It>
+  class const_iterator_base {
+    const compact_map_base *map;
+    It it;
+    const_iterator_base() : map(0) { }
+    const_iterator_base(const compact_map_base* m) : map(m) { }
+    const_iterator_base(const compact_map_base *m, const It& i) : map(m), it(i) { }
+    friend class compact_map_base;
+    friend class iterator_base;
+  public:
+    const_iterator_base(const const_iterator_base& o) {
+      map = o.map;
+      it = o.it;
+    }
+    bool operator==(const const_iterator_base& o) const {
+      return (map == o.map) && (!map->map || it == o.it);
+    }
+    bool operator!=(const const_iterator_base& o) const {
+      return !(*this == o);;
+    }
+    const_iterator_base& operator=(const const_iterator_base& o) {
+      map = o.map;
+      it = o.it;
+      return *this;
+    }
+    const_iterator_base& operator++() {
+      ++it;
+      return *this;
+    }
+    const_iterator_base& operator--() {
+      --it;
+      return *this;
+    }
+    const std::pair<const Key,T>& operator*() {
+      return *it;
+    }
+    const std::pair<const Key,T>* operator->() {
+      return it.operator->();
+    }
+  };
+  template <class It>
+  class iterator_base {
+  private:
+    const compact_map_base* map;
+    It it;
+    iterator_base() : map(0) { }
+    iterator_base(compact_map_base* m) : map(m) { }
+    iterator_base(compact_map_base* m, const It& i) : map(m), it(i) { }
+    friend class compact_map_base;
+  public:
+    iterator_base(const iterator_base& o) {
+      map = o.map;
+      it = o.it;
+    }
+    bool operator==(const iterator_base& o) const {
+      return (map == o.map) && (!map->map || it == o.it);
+    }
+    bool operator!=(const iterator_base& o) const {
+      return !(*this == o);;
+    }
+    iterator_base& operator=(const iterator_base& o) {
+      map = o.map;
+      it = o.it;
+      return *this;
+    }
+    iterator_base& operator++() {
+      ++it;
+      return *this;
+    }
+    iterator_base operator++(int) {
+      iterator_base tmp = *this;
+      ++it;
+      return tmp;
+    }
+    iterator_base& operator--() {
+      --it;
+      return *this;
+    }
+    std::pair<const Key,T>& operator*() {
+      return *it;
+    }
+    std::pair<const Key,T>* operator->() {
+      return it.operator->();
+    }
+    operator const_iterator_base<It>() const {
+      return const_iterator_base<It>(map, it);
+    }
+  };
+
+public:
+  class iterator : public iterator_base<typename Map::iterator> {
+    public:
+      iterator() { }
+      iterator(const iterator_base<typename Map::iterator>& o)
+	: iterator_base<typename Map::iterator>(o) { }
+      iterator(compact_map_base* m) : iterator_base<typename Map::iterator>(m) { }
+      iterator(compact_map_base* m, const typename Map::iterator& i)
+	: iterator_base<typename Map::iterator>(m, i) { }
+  };
+  class const_iterator : public const_iterator_base<typename Map::const_iterator> {
+    public:
+      const_iterator() { }
+      const_iterator(const iterator_base<typename Map::const_iterator>& o)
+	: const_iterator_base<typename Map::const_iterator>(o) { }
+      const_iterator(const compact_map_base* m) : const_iterator_base<typename Map::const_iterator>(m) { }
+      const_iterator(const compact_map_base* m, const typename Map::const_iterator& i)
+	: const_iterator_base<typename Map::const_iterator>(m, i) { }
+  };
+  class reverse_iterator : public iterator_base<typename Map::reverse_iterator> {
+    public:
+      reverse_iterator() { }
+      reverse_iterator(const iterator_base<typename Map::reverse_iterator>& o)
+	: iterator_base<typename Map::reverse_iterator>(o) { }
+      reverse_iterator(compact_map_base* m) : iterator_base<typename Map::reverse_iterator>(m) { }
+      reverse_iterator(compact_map_base* m, const typename Map::reverse_iterator& i)
+	: iterator_base<typename Map::reverse_iterator>(m, i) { }
+  };
+  class const_reverse_iterator : public const_iterator_base<typename Map::const_reverse_iterator> {
+    public:
+      const_reverse_iterator() { }
+      const_reverse_iterator(const iterator_base<typename Map::const_reverse_iterator>& o)
+	: iterator_base<typename Map::const_reverse_iterator>(o) { }
+      const_reverse_iterator(const compact_map_base* m) : const_iterator_base<typename Map::const_reverse_iterator>(m) { }
+      const_reverse_iterator(const compact_map_base* m, const typename Map::const_reverse_iterator& i)
+	: const_iterator_base<typename Map::const_reverse_iterator>(m, i) { }
+  };
+  compact_map_base(const compact_map_base& o) {
+    if (o.map) {
+      alloc_internal();
+      *map = *o.map;
+    }
+  }
+  compact_map_base() {}
+  ~compact_map_base() {}
+
+  bool empty() const {
+    return !map || map->empty();
+  }
+  size_t size() const {
+    return map ? map->size() : 0;
+  }
+  bool operator==(const compact_map_base& o) const {
+    return (empty() && o.empty()) || (map && o.map && *map == *o.map);
+  }
+  bool operator!=(const compact_map_base& o) const {
+    return !(*this == o);
+  }
+  size_t count (const Key& k) const {
+    return map ? map->count(k) : 0;
+  }
+  iterator erase (iterator p) {
+    if (map) {
+      ceph_assert(this == p.map);
+      auto it = map->erase(p.it);
+      if (map->empty()) {
+        free_internal();
+        return iterator(this);
+      } else {
+        return iterator(this, it);
+      }
+    } else {
+      return iterator(this);
+    }
+  }
+  size_t erase (const Key& k) {
+    if (!map)
+      return 0;
+    size_t r = map->erase(k);
+    if (map->empty())
+	free_internal();
+    return r;
+  }
+  void clear() {
+    free_internal();
+  }
+  void swap(compact_map_base& o) {
+    map.swap(o.map);
+  }
+  compact_map_base& operator=(const compact_map_base& o) {
+    if (o.map) {
+      alloc_internal();
+      *map = *o.map;
+    } else
+      free_internal();
+    return *this;
+  }
+  iterator insert(const std::pair<const Key, T>& val) {
+    alloc_internal();
+    return iterator(this, map->insert(val));
+  }
+  template <class... Args>
+  std::pair<iterator,bool> emplace ( Args&&... args ) {
+    alloc_internal();
+    auto em = map->emplace(std::forward<Args>(args)...);
+    return std::pair<iterator,bool>(iterator(this, em.first), em.second);
+  }
+  iterator begin() {
+   if (!map)
+     return iterator(this);
+   return iterator(this, map->begin());
+  }
+  iterator end() {
+   if (!map)
+     return iterator(this);
+   return iterator(this, map->end());
+  }
+  reverse_iterator rbegin() {
+   if (!map)
+     return reverse_iterator(this);
+   return reverse_iterator(this, map->rbegin());
+  }
+  reverse_iterator rend() {
+   if (!map)
+     return reverse_iterator(this);
+   return reverse_iterator(this, map->rend());
+  }
+  iterator find(const Key& k) {
+    if (!map)
+      return iterator(this);
+    return iterator(this, map->find(k));
+  }
+  iterator lower_bound(const Key& k) {
+    if (!map)
+      return iterator(this);
+    return iterator(this, map->lower_bound(k));
+  }
+  iterator upper_bound(const Key& k) {
+    if (!map)
+      return iterator(this);
+    return iterator(this, map->upper_bound(k));
+  }
+  const_iterator begin() const {
+   if (!map)
+     return const_iterator(this);
+   return const_iterator(this, map->begin());
+  }
+  const_iterator end() const {
+   if (!map)
+     return const_iterator(this);
+   return const_iterator(this, map->end());
+  }
+  const_reverse_iterator rbegin() const {
+   if (!map)
+     return const_reverse_iterator(this);
+   return const_reverse_iterator(this, map->rbegin());
+  }
+  const_reverse_iterator rend() const {
+   if (!map)
+     return const_reverse_iterator(this);
+   return const_reverse_iterator(this, map->rend());
+  }
+  const_iterator find(const Key& k) const {
+    if (!map)
+      return const_iterator(this);
+    return const_iterator(this, map->find(k));
+  }
+  const_iterator lower_bound(const Key& k) const {
+    if (!map)
+      return const_iterator(this);
+    return const_iterator(this, map->lower_bound(k));
+  }
+  const_iterator upper_bound(const Key& k) const {
+    if (!map)
+      return const_iterator(this);
+    return const_iterator(this, map->upper_bound(k));
+  }
+  void encode(ceph::buffer::list &bl) const {
+    using ceph::encode;
+    if (map)
+      encode(*map, bl);
+    else
+      encode((uint32_t)0, bl);
+  }
+  void encode(ceph::buffer::list &bl, uint64_t features) const {
+    using ceph::encode;
+    if (map)
+      encode(*map, bl, features);
+    else
+      encode((uint32_t)0, bl);
+  }
+  void decode(ceph::buffer::list::const_iterator& p) {
+    using ceph::decode;
+    using ceph::decode_nohead;
+    uint32_t n;
+    decode(n, p);
+    if (n > 0) {
+      alloc_internal();
+      decode_nohead(n, *map, p);
+    } else
+      free_internal();
+  }
+};
+
+template<class Key, class T, class Map>
+inline void encode(const compact_map_base<Key, T, Map>& m, ceph::buffer::list& bl) {
+  m.encode(bl);
+}
+template<class Key, class T, class Map>
+inline void encode(const compact_map_base<Key, T, Map>& m, ceph::buffer::list& bl,
+		   uint64_t features) {
+  m.encode(bl, features);
+}
+template<class Key, class T, class Map>
+inline void decode(compact_map_base<Key, T, Map>& m, ceph::buffer::list::const_iterator& p) {
+  m.decode(p);
+}
+
+template <class Key, class T, class Compare = std::less<Key>, class Alloc = std::allocator< std::pair<const Key, T> > >
+class compact_map : public compact_map_base<Key, T, std::map<Key,T,Compare,Alloc> > {
+public:
+  T& operator[](const Key& k) {
+    this->alloc_internal();
+    return (*(this->map))[k];
+  }
+};
+
+template <class Key, class T, class Compare = std::less<Key>, class Alloc = std::allocator< std::pair<const Key, T> > >
+inline std::ostream& operator<<(std::ostream& out, const compact_map<Key, T, Compare, Alloc>& m)
+{
+  out << "{";
+  bool first = true;
+  for (const auto &p : m) {
+    if (!first)
+      out << ",";
+    out << p.first << "=" << p.second;
+    first = false;
+  }
+  out << "}";
+  return out;
+}
+
+template <class Key, class T, class Compare = std::less<Key>, class Alloc = std::allocator< std::pair<const Key, T> > >
+class compact_multimap : public compact_map_base<Key, T, std::multimap<Key,T,Compare,Alloc> > {
+};
+
+template <class Key, class T, class Compare = std::less<Key>, class Alloc = std::allocator< std::pair<const Key, T> > >
+inline std::ostream& operator<<(std::ostream& out, const compact_multimap<Key, T, Compare, Alloc>& m)
+{
+  out << "{{";
+  bool first = true;
+  for (const auto &p : m) {
+    if (!first)
+      out << ",";
+    out << p.first << "=" << p.second;
+    first = false;
+  }
+  out << "}}";
+  return out;
+}
+#endif