stl_rope.h

TSP问题的一个类库 有源代码和stl

// The internal data structure for representing a rope.  This is
// private to the implementation.  A rope is really just a pointer
// to one of these.
//
// A few basic functions for manipulating this data structure
// are members of _RopeRep.  Most of the more complex algorithms
// are implemented as rope members.
//
// Some of the static member functions of _RopeRep have identically
// named functions in rope that simply invoke the _RopeRep versions.
//
// A macro to introduce various allocation and deallocation functions
// These need to be defined differently depending on whether or not
// we are using standard conforming allocators, and whether the allocator
// instances have real state.  Thus this macro is invoked repeatedly
// with different definitions of __ROPE_DEFINE_ALLOC.
// __ROPE_DEFINE_ALLOC(type,name) defines 
//   type * name_allocate(size_t) and
//   void name_deallocate(tipe *, size_t)
// Both functions may or may not be static.

#define __ROPE_DEFINE_ALLOCS(__a) \
        __ROPE_DEFINE_ALLOC(_CharT,_Data) /* character data */ \
        typedef _Rope_RopeConcatenation<_CharT,__a> __C; \
        __ROPE_DEFINE_ALLOC(__C,_C) \
        typedef _Rope_RopeLeaf<_CharT,__a> __L; \
        __ROPE_DEFINE_ALLOC(__L,_L) \
        typedef _Rope_RopeFunction<_CharT,__a> __F; \
        __ROPE_DEFINE_ALLOC(__F,_F) \
        typedef _Rope_RopeSubstring<_CharT,__a> __S; \
        __ROPE_DEFINE_ALLOC(__S,_S)

//  Internal rope nodes potentially store a copy of the allocator
//  instance used to allocate them.  This is mostly redundant.
//  But the alternative would be to pass allocator instances around
//  in some form to nearly all internal functions, since any pointer
//  assignment may result in a zero reference count and thus require
//  deallocation.
//  The _Rope_rep_base class encapsulates
//  the differences between SGI-style allocators and standard-conforming
//  allocators.

#ifdef __STL_USE_STD_ALLOCATORS

#define __STATIC_IF_SGI_ALLOC  /* not static */

// Base class for ordinary allocators.
template <class _CharT, class _Allocator, bool _IsStatic>
class _Rope_rep_alloc_base {
public:
  typedef typename _Alloc_traits<_CharT,_Allocator>::allocator_type
          allocator_type;
  allocator_type get_allocator() const { return _M_data_allocator; }
  _Rope_rep_alloc_base(size_t __size, const allocator_type& __a)
        : _M_size(__size), _M_data_allocator(__a) {}
  size_t _M_size;       // This is here only to avoid wasting space
                // for an otherwise empty base class.

  
protected:
    allocator_type _M_data_allocator;

# define __ROPE_DEFINE_ALLOC(_Tp, __name) \
        typedef typename \
          _Alloc_traits<_Tp,_Allocator>::allocator_type __name##Allocator; \
        /*static*/ _Tp * __name##_allocate(size_t __n) \
          { return __name##Allocator(_M_data_allocator).allocate(__n); } \
        void __name##_deallocate(_Tp* __p, size_t __n) \
          { __name##Allocator(_M_data_allocator).deallocate(__p, __n); }
  __ROPE_DEFINE_ALLOCS(_Allocator);
# undef __ROPE_DEFINE_ALLOC
};

// Specialization for allocators that have the property that we don't
//  actually have to store an allocator object.  
template <class _CharT, class _Allocator>
class _Rope_rep_alloc_base<_CharT,_Allocator,true> {
public:
  typedef typename _Alloc_traits<_CharT,_Allocator>::allocator_type
          allocator_type;
  allocator_type get_allocator() const { return allocator_type(); }
  _Rope_rep_alloc_base(size_t __size, const allocator_type&)
                : _M_size(__size) {}
  size_t _M_size;
  
protected:

# define __ROPE_DEFINE_ALLOC(_Tp, __name) \
        typedef typename \
          _Alloc_traits<_Tp,_Allocator>::_Alloc_type __name##Alloc; \
        typedef typename \
          _Alloc_traits<_Tp,_Allocator>::allocator_type __name##Allocator; \
        static _Tp* __name##_allocate(size_t __n) \
                { return __name##Alloc::allocate(__n); } \
        void __name##_deallocate(_Tp *__p, size_t __n) \
                { __name##Alloc::deallocate(__p, __n); }
  __ROPE_DEFINE_ALLOCS(_Allocator);
# undef __ROPE_DEFINE_ALLOC
};

template <class _CharT, class _Alloc>
struct _Rope_rep_base
  : public _Rope_rep_alloc_base<_CharT,_Alloc,
                                _Alloc_traits<_CharT,_Alloc>::_S_instanceless>
{
  typedef _Rope_rep_alloc_base<_CharT,_Alloc,
                               _Alloc_traits<_CharT,_Alloc>::_S_instanceless>
          _Base;
  typedef typename _Base::allocator_type allocator_type;
  _Rope_rep_base(size_t __size, const allocator_type& __a)
    : _Base(__size, __a) {}
};    

#else /* !__STL_USE_STD_ALLOCATORS */

#define __STATIC_IF_SGI_ALLOC static

template <class _CharT, class _Alloc> 
class _Rope_rep_base {
public:
  typedef _Alloc allocator_type;
  static allocator_type get_allocator() { return allocator_type(); }
  _Rope_rep_base(size_t __size, const allocator_type&) : _M_size(__size) {}
  size_t _M_size;

protected:

# define __ROPE_DEFINE_ALLOC(_Tp, __name) \
        typedef simple_alloc<_Tp, _Alloc> __name##Alloc; \
        static _Tp* __name##_allocate(size_t __n) \
                { return __name##Alloc::allocate(__n); } \
        static void __name##_deallocate(_Tp* __p, size_t __n) \
                { __name##Alloc::deallocate(__p, __n); }
  __ROPE_DEFINE_ALLOCS(_Alloc);
# undef __ROPE_DEFINE_ALLOC
};

#endif /* __STL_USE_STD_ALLOCATORS */


template<class _CharT, class _Alloc>
struct _Rope_RopeRep : public _Rope_rep_base<_CharT,_Alloc>
# ifndef __GC
    , _Refcount_Base
# endif
{
    public:
    enum { _S_max_rope_depth = 45 };
    enum _Tag {_S_leaf, _S_concat, _S_substringfn, _S_function};
    _Tag _M_tag:8;
    bool _M_is_balanced:8;
    unsigned char _M_depth;
    __GC_CONST _CharT* _M_c_string;
                        /* Flattened version of string, if needed.  */
                        /* typically 0.                             */
                        /* If it's not 0, then the memory is owned  */
                        /* by this node.                            */
                        /* In the case of a leaf, this may point to */
                        /* the same memory as the data field.       */
    typedef typename _Rope_rep_base<_CharT,_Alloc>::allocator_type
			allocator_type;
    _Rope_RopeRep(_Tag __t, int __d, bool __b, size_t __size,
                  allocator_type __a)
        : _M_tag(__t), _M_depth(__d), _M_is_balanced(__b), _M_c_string(0),
          _Rope_rep_base<_CharT,_Alloc>(__size, __a)
#         ifndef __GC
	  , _Refcount_Base(1)
#	  endif
    { }
#   ifdef __GC
        void _M_incr () {}
#   endif
#   ifdef __STL_USE_STD_ALLOCATORS
        static void _S_free_string(__GC_CONST _CharT*, size_t __len,
                                   allocator_type __a);
#       define __STL_FREE_STRING(__s, __l, __a) _S_free_string(__s, __l, __a);
#   else
        static void _S_free_string(__GC_CONST _CharT*, size_t __len);
#       define __STL_FREE_STRING(__s, __l, __a) _S_free_string(__s, __l);
#   endif
                        // Deallocate data section of a leaf.
                        // This shouldn't be a member function.
                        // But its hard to do anything else at the
                        // moment, because it's templatized w.r.t.
                        // an allocator.
                        // Does nothing if __GC is defined.
#   ifndef __GC
          void _M_free_c_string();
          void _M_free_tree();
                        // Deallocate t. Assumes t is not 0.
          void _M_unref_nonnil()
          {
              if (0 == _M_decr()) _M_free_tree();
          }
          void _M_ref_nonnil()
          {
              _M_incr();
          }
          static void _S_unref(_Rope_RopeRep* __t)
          {
              if (0 != __t) {
                  __t->_M_unref_nonnil();
              }
          }
          static void _S_ref(_Rope_RopeRep* __t)
          {
              if (0 != __t) __t->_M_incr();
          }
          static void _S_free_if_unref(_Rope_RopeRep* __t)
          {
              if (0 != __t && 0 == __t->_M_ref_count) __t->_M_free_tree();
          }
#   else /* __GC */
          void _M_unref_nonnil() {}
          void _M_ref_nonnil() {}
          static void _S_unref(_Rope_RopeRep*) {}
          static void _S_ref(_Rope_RopeRep*) {}
          static void _S_free_if_unref(_Rope_RopeRep*) {}
#   endif

};

template<class _CharT, class _Alloc>
struct _Rope_RopeLeaf : public _Rope_RopeRep<_CharT,_Alloc> {
  public:
    // Apparently needed by VC++
    // The data fields of leaves are allocated with some
    // extra space, to accomodate future growth and for basic
    // character types, to hold a trailing eos character.
    enum { _S_alloc_granularity = 8 };
    static size_t _S_rounded_up_size(size_t __n) {
        size_t __size_with_eos;
             
        if (_S_is_basic_char_type((_CharT*)0)) {
            __size_with_eos = __n + 1;
        } else {
            __size_with_eos = __n;
        }
#       ifdef __GC
           return __size_with_eos;
#       else
           // Allow slop for in-place expansion.
           return (__size_with_eos + _S_alloc_granularity-1)
                        &~ (_S_alloc_granularity-1);
#       endif
    }
    __GC_CONST _CharT* _M_data; /* Not necessarily 0 terminated. */
                                /* The allocated size is         */
                                /* _S_rounded_up_size(size), except */
                                /* in the GC case, in which it   */
                                /* doesn't matter.               */
    typedef typename _Rope_rep_base<_CharT,_Alloc>::allocator_type
			allocator_type;
    _Rope_RopeLeaf(__GC_CONST _CharT* __d, size_t __size, allocator_type __a)
        : _M_data(__d)
        , _Rope_RopeRep<_CharT,_Alloc>(_S_leaf, 0, true, __size, __a)
        {
        __stl_assert(__size > 0);
        if (_S_is_basic_char_type((_CharT *)0)) {
            // already eos terminated.
            _M_c_string = __d;
        }
    }
        // The constructor assumes that d has been allocated with
        // the proper allocator and the properly padded size.
        // In contrast, the destructor deallocates the data:
# ifndef __GC
    ~_Rope_RopeLeaf() {
        if (_M_data != _M_c_string) {
            _M_free_c_string();
        }
        __STL_FREE_STRING(_M_data, _M_size, get_allocator());
    }
# endif
};

template<class _CharT, class _Alloc>
struct _Rope_RopeConcatenation : public _Rope_RopeRep<_CharT,_Alloc> {
  public:
    _Rope_RopeRep<_CharT,_Alloc>* _M_left;
    _Rope_RopeRep<_CharT,_Alloc>* _M_right;
    typedef typename _Rope_rep_base<_CharT,_Alloc>::allocator_type
			allocator_type;
    _Rope_RopeConcatenation(_Rope_RopeRep<_CharT,_Alloc>* __l,
                             _Rope_RopeRep<_CharT,_Alloc>* __r,
                             allocator_type __a)
      : _M_left(__l), _M_right(__r)
      , _Rope_RopeRep<_CharT,_Alloc>(
          _S_concat, max(__l->_M_depth, __r->_M_depth) + 1, false,
          __l->_M_size + __r->_M_size, __a)
      {}
# ifndef __GC
    ~_Rope_RopeConcatenation() {
        _M_free_c_string();
        _M_left->_M_unref_nonnil();
        _M_right->_M_unref_nonnil();
    }
# endif
};

template<class _CharT, class _Alloc>
struct _Rope_RopeFunction : public _Rope_RopeRep<_CharT,_Alloc> {
  public:
    char_producer<_CharT>* _M_fn;
#   ifndef __GC
      bool _M_delete_when_done; // Char_producer is owned by the
                                // rope and should be explicitly
                                // deleted when the rope becomes
                                // inaccessible.
#   else
      // In the GC case, we either register the rope for
      // finalization, or not.  Thus the field is unnecessary;
      // the information is stored in the collector data structures.
      // We do need a finalization procedure to be invoked by the
      // collector.
      static void _S_fn_finalization_proc(void * __tree, void *) {
        delete ((_Rope_RopeFunction *)__tree) -> _M_fn;
      }
#   endif
    typedef typename _Rope_rep_base<_CharT,_Alloc>::allocator_type
					allocator_type;
    _Rope_RopeFunction(char_producer<_CharT>* __f, size_t __size,
                        bool __d, allocator_type __a)
      : _M_fn(__f)
#       ifndef __GC
      , _M_delete_when_done(__d)
#       endif
      , _Rope_RopeRep<_CharT,_Alloc>(_S_function, 0, true, __size, __a) {
        __stl_assert(__size > 0);
#       ifdef __GC
            if (__d) {
                GC_REGISTER_FINALIZER(
                  this, _Rope_RopeFunction::_S_fn_finalization_proc, 0, 0, 0);
            }