Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 297 insertions, 0 deletions

diff --git a/sql/sql_plist.h b/sql/sql_plist.h
new file mode 100644
index 00000000..7f75208c
--- /dev/null
+++ b/sql/sql_plist.h
@@ -0,0 +1,297 @@
+#ifndef SQL_PLIST_H
+#define SQL_PLIST_H
+/* Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+
+template <typename T, typename L>
+class I_P_List_iterator;
+class I_P_List_null_counter;
+template <typename T> class I_P_List_no_push_back;
+
+
+/**
+   Intrusive parameterized list.
+
+   Unlike I_List does not require its elements to be descendant of ilink
+   class and therefore allows them to participate in several such lists
+   simultaneously.
+
+   Unlike List is doubly-linked list and thus supports efficient deletion
+   of element without iterator.
+
+   @param T  Type of elements which will belong to list.
+   @param B  Class which via its methods specifies which members
+             of T should be used for participating in this list.
+             Here is typical layout of such class:
+
+             struct B
+             {
+               static inline T **next_ptr(T *el)
+               {
+                 return &el->next;
+               }
+               static inline T ***prev_ptr(T *el)
+               {
+                 return &el->prev;
+               }
+             };
+   @param C  Policy class specifying how counting of elements in the list
+             should be done. Instance of this class is also used as a place
+             where information about number of list elements is stored.
+             @sa I_P_List_null_counter, I_P_List_counter
+   @param I  Policy class specifying whether I_P_List should support
+             efficient push_back() operation. Instance of this class
+             is used as place where we store information to support
+             this operation.
+             @sa I_P_List_no_push_back, I_P_List_fast_push_back.
+*/
+
+template <typename T, typename B,
+          typename C = I_P_List_null_counter,
+          typename I = I_P_List_no_push_back<T> >
+class I_P_List : public C, public I
+{
+  T *m_first;
+
+  /*
+    Do not prohibit copying of I_P_List object to simplify their usage in
+    backup/restore scenarios. Note that performing any operations on such
+    is a bad idea.
+  */
+public:
+  I_P_List() : I(&m_first), m_first(NULL) {};
+  /*
+    empty() is used in many places in the code instead of a constructor, to
+    initialize a bzero-ed I_P_List instance.
+  */
+
+  inline void empty()      { m_first= NULL; C::reset(); I::set_last(&m_first); }
+  inline bool is_empty() const { return (m_first == NULL); }
+  inline void push_front(T* a)
+  {
+    *B::next_ptr(a)= m_first;
+    if (m_first)
+      *B::prev_ptr(m_first)= B::next_ptr(a);
+    else
+      I::set_last(B::next_ptr(a));
+    m_first= a;
+    *B::prev_ptr(a)= &m_first;
+    C::inc();
+  }
+  inline void push_back(T *a)
+  {
+    T **last= I::get_last();
+    *B::next_ptr(a)= *last;
+    *last= a;
+    *B::prev_ptr(a)= last;
+    I::set_last(B::next_ptr(a));
+    C::inc();
+  }
+  inline void insert_after(T *pos, T *a)
+  {
+    if (pos == NULL)
+      push_front(a);
+    else
+    {
+      *B::next_ptr(a)= *B::next_ptr(pos);
+      *B::prev_ptr(a)= B::next_ptr(pos);
+      *B::next_ptr(pos)= a;
+      if (*B::next_ptr(a))
+      {
+        T *old_next= *B::next_ptr(a);
+        *B::prev_ptr(old_next)= B::next_ptr(a);
+      }
+      else
+        I::set_last(B::next_ptr(a));
+      C::inc();
+    }
+  }
+  inline void remove(T *a)
+  {
+    T *next= *B::next_ptr(a);
+    if (next)
+      *B::prev_ptr(next)= *B::prev_ptr(a);
+    else
+      I::set_last(*B::prev_ptr(a));
+    **B::prev_ptr(a)= next;
+    C::dec();
+  }
+  inline T* front() { return m_first; }
+  inline const T *front() const { return m_first; }
+  inline T* pop_front()
+  {
+    T *result= front();
+
+    if (result)
+      remove(result);
+
+    return result;
+  }
+  void swap(I_P_List<T, B, C> &rhs)
+  {
+    swap_variables(T *, m_first, rhs.m_first);
+    I::swap(rhs);
+    if (m_first)
+      *B::prev_ptr(m_first)= &m_first;
+    else
+      I::set_last(&m_first);
+    if (rhs.m_first)
+      *B::prev_ptr(rhs.m_first)= &rhs.m_first;
+    else
+      I::set_last(&rhs.m_first);
+    C::swap(rhs);
+  }
+  typedef B Adapter;
+  typedef I_P_List<T, B, C, I> Base;
+  typedef I_P_List_iterator<T, Base> Iterator;
+  typedef I_P_List_iterator<const T, Base> Const_Iterator;
+#ifndef _lint
+  friend class I_P_List_iterator<T, Base>;
+  friend class I_P_List_iterator<const T, Base>;
+#endif
+};
+
+
+/**
+   Iterator for I_P_List.
+*/
+
+template <typename T, typename L>
+class I_P_List_iterator
+{
+  const L *list;
+  T *current;
+public:
+  I_P_List_iterator(const L &a)
+    : list(&a), current(a.m_first) {}
+  I_P_List_iterator(const L &a, T* current_arg)
+    : list(&a), current(current_arg) {}
+  inline void init(const L &a)
+  {
+    list= &a;
+    current= a.m_first;
+  }
+  /**
+    Operator for it++
+
+    @note since we save next element pointer, caller may remove current element.
+    Such modification doesn't invalidate iterator.
+  */
+  inline T* operator++(int)
+  {
+    T *result= current;
+    if (result)
+      current= *L::Adapter::next_ptr(current);
+    return result;
+  }
+  /* Operator for ++it */
+  inline T* operator++()
+  {
+    current= *L::Adapter::next_ptr(current);
+    return current;
+  }
+  inline void rewind()
+  {
+    current= list->m_first;
+  }
+};
+
+
+/**
+  Hook class which via its methods specifies which members
+  of T should be used for participating in a intrusive list.
+*/
+
+template <typename T, T* T::*next, T** T::*prev>
+struct I_P_List_adapter
+{
+  static inline T **next_ptr(T *el) { return &(el->*next); }
+  static inline const T* const* next_ptr(const T *el) { return &(el->*next); }
+  static inline T ***prev_ptr(T *el) { return &(el->*prev); }
+};
+
+
+/**
+  Element counting policy class for I_P_List to be used in
+  cases when no element counting should be done.
+*/
+
+class I_P_List_null_counter
+{
+protected:
+  void reset() {}
+  void inc() {}
+  void dec() {}
+  void swap(I_P_List_null_counter &) {}
+};
+
+
+/**
+  Element counting policy class for I_P_List which provides
+  basic element counting.
+*/
+
+class I_P_List_counter
+{
+  uint m_counter;
+protected:
+  I_P_List_counter() : m_counter (0) {}
+  void reset() {m_counter= 0;}
+  void inc() {m_counter++;}
+  void dec() {m_counter--;}
+  void swap(I_P_List_counter &rhs)
+  { swap_variables(uint, m_counter, rhs.m_counter); }
+public:
+  uint elements() const { return m_counter; }
+};
+
+
+/**
+  A null insertion policy class for I_P_List to be used
+  in cases when push_back() operation is not necessary.
+*/
+
+template <typename T> class I_P_List_no_push_back
+{
+protected:
+  I_P_List_no_push_back(T **) {}
+  void set_last(T **) {}
+  /*
+    T** get_last() const method is intentionally left unimplemented
+    in order to prohibit usage of push_back() method in lists which
+    use this policy.
+  */
+  void swap(I_P_List_no_push_back<T> &) {}
+};
+
+
+/**
+  An insertion policy class for I_P_List which can
+  be used when fast push_back() operation is required.
+*/
+
+template <typename T> class I_P_List_fast_push_back
+{
+  T **m_last;
+protected:
+  I_P_List_fast_push_back(T **a) : m_last(a) { };
+  void set_last(T **a) { m_last= a; }
+  T** get_last() const { return m_last; }
+  void swap(I_P_List_fast_push_back<T> &rhs)
+  { swap_variables(T**, m_last, rhs.m_last); }
+};
+
+#endif