From: Roland McGrath <roland@redhat.com>
Date: Sat, 4 Jul 2009 09:03:38 +0000 (-0700)
Subject: subrify some constructor magic.
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8ea6ffc8471c499b9fb3fc5eef0a48899f4187d7;p=thirdparty%2Felfutils.git

subrify some constructor magic.
---

diff --git a/libdw/c++/dwarf_data b/libdw/c++/dwarf_data
index 8e765c5ed..76a44e014 100644
--- a/libdw/c++/dwarf_data
+++ b/libdw/c++/dwarf_data
@@ -669,8 +669,6 @@ namespace elfutils
     };
 
   public:
-    struct nothing {};
-
     template<typename impl>
     struct value
     {
@@ -726,7 +724,7 @@ namespace elfutils
 	   object.  This is what plain assignment does.  This just uses
 	   this pointer, rather than translating it from another file
 	   into this one (which requires a tracker).  */
-	inline value_reference (const value_type &i, const nothing &)
+	inline value_reference (const value_type &i, const subr::nothing &)
 	  : ref (i)
 	{}
 
@@ -876,7 +874,7 @@ namespace elfutils
       typename vw::value_dispatch *_m_value;
       typedef typename impl::debug_info_entry::pointer die_ptr;
 
-      template<typename value, typename arg_type = const nothing>
+      template<typename value, typename arg_type = const subr::nothing>
       struct init
       {
 	inline init (attr_value *av,
diff --git a/libdw/c++/dwarf_edit b/libdw/c++/dwarf_edit
index da7306233..40873e4b2 100644
--- a/libdw/c++/dwarf_edit
+++ b/libdw/c++/dwarf_edit
@@ -105,6 +105,8 @@ namespace elfutils
 
     class debug_info_entry
     {
+      friend class subr::create_container;
+
     public:
 
       class children_type : public std::list<debug_info_entry>
@@ -113,20 +115,18 @@ namespace elfutils
       private:
         inline children_type () {}
 
+	template<typename input, typename tracker>
+	static inline void
+	equivalence (const iterator &out,
+		     const typename input::const_iterator &in, tracker &t)
+	{
+	  t.equivalence (out, in);
+	}
+
 	template<typename input, typename tracker>
 	inline children_type (const input &other, tracker &t)
 	{
-	  for (typename input::const_iterator in = other.begin ();
-	       in != other.end ();
-	       ++in)
-	    {
-	      /* Don't copy-construct the entry from *in here because that
-		 copies it again into the list and destroys the first copy.  */
-	      push_back (debug_info_entry ());
-	      iterator out = --end ();
-	      out->set (*in, t);
-	      t.equivalence (out, in);
-	    }
+	  subr::create_container (this, other, t, equivalence<input, tracker>);
 	}
 
       public:
@@ -270,6 +270,7 @@ namespace elfutils
 
     class compile_unit : public debug_info_entry
     {
+      friend class subr::create_container;
       friend class compile_units;
     private:
       inline compile_unit () : debug_info_entry (::DW_TAG_compile_unit) {}
@@ -294,6 +295,7 @@ namespace elfutils
     class compile_units : public std::list<compile_unit>
     {
       friend class dwarf_edit;
+      friend class subr::create_container;
 
     private:
       typedef std::list<compile_unit> _base;
@@ -305,17 +307,9 @@ namespace elfutils
       template<typename input, typename tracker>
       inline compile_units (const input &other, tracker &t)
       {
-	for (typename input::const_iterator in = other.begin ();
-	     in != other.end ();
-	     ++in)
-	  {
-	    /* Don't copy-construct the entry from *in here because that
-	       copies it again into the list and destroys the first copy.  */
-	    push_back (compile_unit ());
-	    iterator out = --end ();
-	    out->set (*in, t);
-	  }
+	subr::create_container (this, other, t);
       }
+
 #if 0				// dwarf_output might use this (?)
       template<typename input, typename tracker>
       inline compile_units (const input &units, tracker &t)
diff --git a/libdw/c++/dwarf_output b/libdw/c++/dwarf_output
index d8c7b9c56..4202fb16d 100644
--- a/libdw/c++/dwarf_output
+++ b/libdw/c++/dwarf_output
@@ -331,7 +331,7 @@ namespace elfutils
 
       template<typename flavor, typename input>
       static inline value_dispatch *
-      make (flavor *&, const input &, const dwarf_data::nothing &)
+      make (flavor *&, const input &, const subr::nothing &)
       {
 	throw std::logic_error ("dwarf_output cannot be default-constructed");
       }
@@ -366,7 +366,7 @@ namespace elfutils
       {
 	friend class debug_info_entry;
       private:
-        children_type () {}
+        inline children_type () {}
 
 	template<typename input>
 	inline children_type (const input &other, dwarf_output_collector &c)
diff --git a/libdw/c++/subr.hh b/libdw/c++/subr.hh
index b768abe70..02d95b381 100644
--- a/libdw/c++/subr.hh
+++ b/libdw/c++/subr.hh
@@ -784,6 +784,34 @@ namespace elfutils
 	  _m_tracker->abort ();
       }
     };
+
+    struct nothing
+    {
+      template<typename... args>
+      inline void operator () (args&&...) const {}
+    };
+
+    // Class instead of function so it can be a friend.
+    struct create_container
+    {
+      template<typename container, typename input, typename arg_type,
+	       typename hook_type = const nothing>
+      inline create_container (container *me, const input &other,
+			       arg_type &arg, hook_type &hook = hook_type ())
+      	{
+	  for (typename input::const_iterator in = other.begin ();
+	       in != other.end ();
+	       ++in)
+	    {
+	      /* Don't copy-construct the entry from *in here because that
+		 copies it again into the list and destroys the first copy.  */
+	      me->push_back (typename container::value_type ());
+	      typename container::iterator out = --me->end ();
+	      out->set (*in, arg);
+	      hook (out, in, arg);
+	    }
+	}
+    };
   };
 };