include/unihashtree.h

   1 /* -*- Mode: C++ -*-
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 1997-2002 Net Integration Technologies, Inc.
   4  *
   5  * UniConf low-level tree storage abstraction.
   6  */
   7 #ifndef __UNIHASHTREE_H
   8 #define __UNIHASHTREE_H
   9
  10 #include "uniconfkey.h"
  11 #include "wvtr1.h"
  12 #include "wvscatterhash.h"
  13
  14 class UniHashTreeBase;
  15
  16 // parameters: a node (won't be NULL), userdata
  17 typedef wv::function<void(const UniHashTreeBase*,
  18                           void*)> UniHashTreeBaseVisitor;
  19 // parameters: 1st node (may be NULL), 2nd node (may be NULL), userdata
  20 typedef wv::function<bool(const UniHashTreeBase*,
  21                           const UniHashTreeBase*)> UniHashTreeBaseComparator;
  22
  23 class UniHashTreeBase
  24 {
  25 protected:
  26     struct Accessor
  27     {
  28         static const UniConfKey *get_key(const UniHashTreeBase *obj)
  29             { return &obj->key(); }
  30     };
  31
  32     typedef WvScatterHash<UniHashTreeBase, UniConfKey, Accessor> Container;
  33     typedef UniHashTreeBaseVisitor BaseVisitor;
  34     typedef UniHashTreeBaseComparator BaseComparator;
  35
  36 public:
  37     ~UniHashTreeBase();
  38
  39     /** Returns the key field. */
  40     const UniConfKey &key() const
  41         { return xkey; }
  42
  43     /** Returns true if the node has children. */
  44     bool haschildren() const;
  45
  46 protected:
  47     UniHashTreeBase(UniHashTreeBase *parent, const UniConfKey &key);
  48
  49     UniConfKey _fullkey(const UniHashTreeBase *ancestor = NULL) const;
  50     UniHashTreeBase *_find(const UniConfKey &key) const;
  51     UniHashTreeBase *_findchild(const UniConfKey &key) const;
  52
  53     static bool _recursivecompare(
  54         const UniHashTreeBase *a, const UniHashTreeBase *b,
  55         const UniHashTreeBaseComparator &comparator);
  56
  57     static void _recursive_unsorted_visit(
  58         const UniHashTreeBase *a,
  59         const UniHashTreeBaseVisitor &visitor, void *userdata,
  60         bool preorder, bool postorder);
  61
  62     UniHashTreeBase *xparent; /*!< the parent of this subtree */
  63     Container *xchildren; /*!< the hash table of children */
  64
  65 private:
  66     void _setparent(UniHashTreeBase *parent);
  67     UniHashTreeBase *_root() const;
  68
  69     /** Called by a child to link itself to this node. */
  70     void link(UniHashTreeBase *node);
  71
  72     /** Called by a child to unlink itself from this node. */
  73     void unlink(UniHashTreeBase *node);
  74
  75     UniConfKey xkey;   /*!< the name of this entry */
  76
  77 protected:
  78     class Iter : public Container::Iter
  79     {
  80     public:
  81         Iter(UniHashTreeBase &b) : Container::Iter(*b.xchildren) { }
  82     };
  83     friend class Iter;
  84 };
  85
  86 #endif //__UNIHASHTREE_H