[binutils-gdb] Make intrusive_list_node's next/prev private

[binutils-gdb] Make intrusive_list_node's next/prev private

[Pedro Alves]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=50b032ebc0519a2b2585c499b9901fde9a0eccee

commit 50b032ebc0519a2b2585c499b9901fde9a0eccee
Author: Pedro Alves <pedro@palves.net>
Date:   Fri Apr 8 20:03:46 2022 +0100

    Make intrusive_list_node's next/prev private
    
    Tromey noticed that intrusive_list_node leaves its data members
    public, which seems sub-optimal.
    
    This commit makes intrusive_list_node's data fields private.
    intrusive_list_iterator, intrusive_list_reverse_iterator, and
    intrusive_list do need to access the fields, so they are made friends.
    
    Change-Id: Ia8b306b40344cc218d423c8dfb8355207a612ac5

Diff:
---
 gdbsupport/intrusive_list.h | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/gdbsupport/intrusive_list.h b/gdbsupport/intrusive_list.h
index 77eeeeec5fd..6812266159a 100644
--- a/gdbsupport/intrusive_list.h
+++ b/gdbsupport/intrusive_list.h
@@ -24,15 +24,26 @@
 /* A list node.  The elements put in an intrusive_list either inherit
    from this, or have a field of this type.  */
 template<typename T>
-struct intrusive_list_node
+class intrusive_list_node
 {
+public:
   bool is_linked () const
   {
     return next != INTRUSIVE_LIST_UNLINKED_VALUE;
   }
 
+private:
   T *next = INTRUSIVE_LIST_UNLINKED_VALUE;
   T *prev = INTRUSIVE_LIST_UNLINKED_VALUE;
+
+  template<typename T2, typename AsNode>
+  friend struct intrusive_list_iterator;
+
+  template<typename T2, typename AsNode>
+  friend struct intrusive_list_reverse_iterator;
+
+  template<typename T2, typename AsNode>
+  friend struct intrusive_list;
 };
 
 /* Follows a couple types used by intrusive_list as template parameter to find