//
// stateout.h
//
// Copyright (C) 1998 Limit Point Systems, Inc.
//
// Author: Curtis Janssen <cljanss@limitpt.com>
// Maintainer: LPS
//
// This file is part of the SC Toolkit.
//
// The SC Toolkit is free software; you can redistribute it and/or modify
// it under the terms of the GNU Library General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// The SC Toolkit 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 Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public License
// along with the SC Toolkit; see the file COPYING.LIB.  If not, write to
// the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
//
// The U.S. Government is granted a limited license as per AL 91-7.
//

#ifndef _util_state_stateout_h
#define _util_state_stateout_h

#ifdef __GNUC__
#pragma interface
#endif

#include <string>
#include <vector>
#include <map>

#include <util/class/class.h>
#include <util/state/state.h>

namespace sc {

class StateOutData {
  public:
    int num;
    int size;
    int type;
    int offset;

    StateOutData(): num(0), size(0), type(0), offset(0) {}
};

/** Serializes objects that derive from SavableState.

    StateOut keeps track
    of pointers to data so that two references to the same
    piece of data do not result in that data being sent to the
    output device two times.
 */
class StateOut: public DescribedClass {
    friend class SavableState;
    friend class TranslateDataOut;
  private:
    // do not allow copy constructor or assignment
    StateOut(const StateOut&);
    void operator=(const StateOut&);
    int have_cd_;
  protected:
    int dir_loc_loc_;
    TranslateDataOut *translate_;
    int copy_references_;
    int next_object_number_;
    std::map<Ref<SavableState>,StateOutData> ps_;
    std::map<ClassDescP,int> classidmap_;
    int nextclassid_;
    int node_to_node_;
    virtual int put_array_void(const void*,int);
    virtual int putparents(const ClassDesc*);

    void put_directory();

    // The following members are called by friend SavableState

    void have_classdesc() { have_cd_ = 1; }
    int need_classdesc() { int tmp = have_cd_; have_cd_ = 0; return !tmp; }

    /** This will prepare StateOut to output a pointer to data.  It first
        checks to see if the data has already been saved.  If it has, then
        a reference to this data is saved.  Otherwise the object is written
        out. */
    virtual int putobject(const Ref<SavableState> &);

    /// Write out information about the given ClassDesc.
    virtual int put(const ClassDesc*);
  public:
    StateOut();
    virtual ~StateOut();

    /// Write out header information.
    virtual void put_header();

    /** This is like put except the length of the char array is determined
        by interpreting the character array as a character string. */
    virtual int putstring(const char*);

    /// Write out a std::string object
    virtual int put(const std::string &);

    /// Write the given datum.
    virtual int put(char r);
    virtual int put(unsigned int r);
    virtual int put(int r);
    virtual int put(bool r);
    virtual int put(unsigned long r);
    virtual int put(float r);
    virtual int put(double r);
    /** Write the given array data.  Size information is also saved.  The
        data is allocated and read by the get(T*&) routines. */
    virtual int put(const char*,int);
    virtual int put(const unsigned int*,int);
    virtual int put(const int*,int);
    virtual int put(const float*,int);
    virtual int put(const double*,int);
    /** Put arrays of data.  No size information is stored.  This
        data is read by the get_array_T routines. */
    virtual int put_array_char(const char*p,int size);
    virtual int put_array_uint(const unsigned int*p,int size);
    virtual int put_array_int(const int*p,int size);
    virtual int put_array_float(const float*p,int size);
    virtual int put_array_double(const double*p,int size);

    /// Write an STL vector of data.
    template <class T>
    int put(typename std::vector<T> &v) {
      int l = v.size();
      int r = put(l);
      if (l) { for (int i=0; i<l; i++) r += put(v[i]); }
      return r;
    }

    /** Don't keep track of pointers to objects.  Calling this
        causes duplicated references to objects to be copied.
        The directory will not contain the forgotten objects. */
    void forget_references();
    /** If a reference to an object that has already been written
        is encountered, copy it instead of generating a reference
        to the first object.
        The directory will not be updated with new objects. */
    void copy_references();

    /// Returns true if this object uses a directory.
    virtual int use_directory();

    /// Flush out any remaining data.
    virtual void flush();

    /** True if this is a node to node save/restore.  This is
        necessary for classes that try to avoid saving databases
        to files that can otherwise be read in, but want to avoid
        reading the database from disk on all nodes. */
    int node_to_node() const { return node_to_node_; }

    /** Returns the current position in the file.  The default
        implementation returns 0. */
    virtual int tell();
    /** Set the current position in the file.  The default implementation
        does nothing. */
    virtual void seek(int loc);
    /** Return non-zero if tell and seek do anything sensible.  The
        default implementation returns 0. */
    virtual int seekable();
  };

}

#endif

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