class.h

//
// class.h
//
// Copyright (C) 1996 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.
//

#ifdef __GNUG__
#pragma interface
#endif

#ifndef _util_class_class_h
#define _util_class_class_h

#include <map>
#include <set>
#include <string>

#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <iostream>
#include <iomanip>
#include <typeinfo>
#include <util/ref/ref.h>
#include <util/misc/exenv.h>

namespace sc {

class DescribedClass;
class ClassDesc;
typedef ClassDesc* ClassDescP;
typedef const ClassDesc* CClassDescP;

class ClassDesc;

class ParentClass
{
  public:
    enum Access { Private, Protected, Public };
  private:
    Access _access;
    int _is_virtual;
    ClassDesc* _classdesc;
  public:
    ParentClass(ClassDesc*,Access access = Private,int is_virtual = 0);
    ParentClass(const ParentClass&);
    ~ParentClass();
    int is_virtual() const;
    Access access() const { return _access; }
    const ClassDesc* classdesc() const;
    void change_classdesc(ClassDesc*n);
};

class ParentClasses
{
  private:
    int _n;
    ParentClass** _classes;
    void add(ParentClass*);
    // do not allow copy constructor or assignment
    ParentClasses(const ParentClasses&);
    void operator=(const ParentClasses&);
  public:
    ParentClasses();
    void init(const char*);
    ~ParentClasses();
    ParentClass& parent(int i) { return *_classes[i]; }
    const ParentClass& parent(int i) const { return *_classes[i]; }
    ParentClass& operator[](int i) { return *_classes[i]; }
    const ParentClass& operator[](int i) const { return *_classes[i]; }
    int n() const { return _n; }
    void change_parent(ClassDesc*oldcd,ClassDesc*newcd);
};
    

class KeyVal;
class StateIn;

template <class T>
DescribedClass* create()
{
  return new T;
}

template <class T>
DescribedClass* create(const Ref<KeyVal>& keyval)
{
  return new T(keyval);
}

template <class T>
DescribedClass* create(StateIn& statein)
{
  return new T(statein);
}

class type_info_key {
  private:
    const std::type_info *ti_;
  public:
    type_info_key(): ti_(0) {}
    type_info_key(const std::type_info *ti): ti_(ti) {}
    type_info_key& operator=(const type_info_key&);
    int operator==(const type_info_key&) const;
    int operator<(const type_info_key&) const;
    int cmp(const type_info_key&) const;
};

class ClassDesc: public Identity {
    friend class ParentClasses;
  private:
    static std::map<std::string,ClassDescP> *all_;
    static std::map<type_info_key,ClassDescP> *type_info_all_;
    static char * classlib_search_path_;
    static std::set<std::string> *unresolved_parents_;

    char* classname_;
    int version_;
    ParentClasses parents_;
    std::set<std::string> *children_;
    DescribedClass* (*ctor_)();
    DescribedClass* (*keyvalctor_)(const Ref<KeyVal>&);
    DescribedClass* (*stateinctor_)(StateIn&);
    const std::type_info *ti_;

    void change_parent(ClassDesc*oldcd,ClassDesc*newcd);

    // do not allow copy constructor or assignment
    ClassDesc(const ClassDesc&);
    void operator=(const ClassDesc&);

    // this is used for temporary parent class descriptors
    ClassDesc(const char*);
    void init(const char*,int=1,const char* p=0,
              const std::type_info *ti=0,
              DescribedClass* (*ctor)()=0,
              DescribedClass* (*keyvalctor)(const Ref<KeyVal>&)=0,
              DescribedClass* (*stateinctor)(StateIn&)=0);
  public:
    ClassDesc(const std::type_info&, const char*,int=1,const char* p=0,
              DescribedClass* (*ctor)()=0,
              DescribedClass* (*keyvalctor)(const Ref<KeyVal>&)=0,
              DescribedClass* (*stateinctor)(StateIn&)=0);
    ~ClassDesc();

    static std::map<std::string,ClassDescP>& all();
    const ParentClasses& parents() const { return parents_; }

    static void list_all_classes();
    static ClassDesc* name_to_class_desc(const char*);
    static ClassDesc *class_desc(const std::type_info &);
    const char* name() const { return classname_; }
    int version() const { return version_; }
    DescribedClass* create_described_class() const;
    virtual DescribedClass* create() const;
    virtual DescribedClass* create(const Ref<KeyVal>&) const;
    virtual DescribedClass* create(StateIn&) const;

    static int load_class(const char* classname);
};

class DescribedClass : public RefCount {
  public:
    DescribedClass();
    DescribedClass(const DescribedClass&);
    DescribedClass& operator=(const DescribedClass&);
    virtual ~DescribedClass();
    ClassDesc* class_desc() const throw();
    const char* class_name() const;
    int class_version() const;
    virtual void print(std::ostream& = ExEnv::out0()) const;
  };

template <class T>
inline ClassDesc *
class_desc()
{
  return ClassDesc::class_desc(typeid(T));
}

inline ClassDesc *
class_desc(DescribedClass *d)
{
  return ClassDesc::class_desc(typeid(*d));
}

template<class T>
inline T
require_dynamic_cast(DescribedClass*p,const char * errmsg,...)
{
  T t = dynamic_cast<T>(p);
  if (p && !t) {
      va_list args;
      va_start(args,errmsg);
      fprintf(stderr,"A required dynamic_cast failed in: ");
      vfprintf(stderr,errmsg,args);
      fprintf(stderr,"\nwanted type \"%s\" but got \"%s\"\n",
              typeid(T).name(),p->class_desc()->name());
      fflush(stderr);
      va_end(args);
      abort();
  }
  return t;
}

template<class T>
inline T
require_dynamic_cast(const DescribedClass*p,const char * errmsg,...)
{
  T t = dynamic_cast<T>(p);
  if (p && !t) {
      va_list args;
      va_start(args,errmsg);
      fprintf(stderr,"A required dynamic_cast failed in: ");
      vfprintf(stderr,errmsg,args);
      fprintf(stderr,"\nwanted type \"%s\" but got \"%s\"\n",
              typeid(T).name(),p->class_desc()->name());
      fflush(stderr);
      va_end(args);
      abort();
  }
  return t;
}

template <class A>
class ForceLinkBase {
  public:
    ForceLinkBase() {};
    virtual ~ForceLinkBase() {};
    virtual DescribedClass *create(A) = 0;
};

template <class T, class A = const Ref<KeyVal> &>
class ForceLink: public ForceLinkBase<A> {
  public:
    ForceLink() {};
    virtual ~ForceLink() {};
    DescribedClass *create(A a) { return new T(a); }
};

}

#endif

// Local Variables:
// mode: c++
// c-file-style: "CLJ"
// End:

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