// field.h - Header file for fieldID instances.  -*- c++ -*-

/* Copyright (C) 1998, 1999  Cygnus Solutions

   This file is part of libgcj.

This software is copyrighted work licensed under the terms of the
Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
details.  */

#ifndef __GCJ_FIELD_H__
#define __GCJ_FIELD_H__

#include <java/lang/Class.h>
#include <java/lang/reflect/Field.h>

#define _Jv_FIELD_UNRESOLVED_FLAG	0x8000
#define	_Jv_FIELD_CONSTANT_VALUE	0x4000

struct _Jv_Field
{
#ifndef COMPACT_FIELDS
  struct _Jv_Utf8Const*	name;
#endif

  /* The type of the field, if isResolved().
     If !isResolved():  The fields's signature as a (Utf8Const*). */
  jclass		type;

  _Jv_ushort		flags;

#ifdef COMPACT_FIELDS
  short			nameIndex;  /* ofsfet in class's name table */
#else
  _Jv_ushort		bsize;  /* not really needed ... */
#endif

  union {
    int			boffset;  /* offset in bytes for instance field */
    void*		addr;  /* address of static field */
  } u;

#ifdef __cplusplus
  jboolean isResolved ()
  { return ! (flags & _Jv_FIELD_UNRESOLVED_FLAG); }

  public:

  int getOffset () { return u.boffset; }

  jobject getObjectField (jobject obj)
  { return *(jobject *)((char *)obj + getOffset ()); }

  jfieldID getNextInstanceField () { return this + 1; }

  jboolean isRef () 
    { 
      if (!isResolved ()) 
	{
	  char first = ((_Jv_Utf8Const*)type)->data[0]; 
	  return first == '[' || first == 'L';
	}
      else
	{
	  return ! type->isPrimitive ();
	}
    }

  // FIXME - may need to mask off internal flags.
  int getModifiers() { return flags; }

#ifdef COMPACT_FIELDS
  _Jv_Utf8Const * getNameUtf8Const (jclass cls)
  { return clas->fieldNames + nameIndex; }
#else
  _Jv_Utf8Const * getNameUtf8Const (jclass) { return name; }
#endif
#endif
};

#ifdef __cplusplus
inline jbyte
_Jv_GetStaticByteField (jclass, _Jv_Field* field)
{
  return * (jbyte *) field->u.addr;
}

inline jshort
_Jv_GetStaticShortField (jclass, _Jv_Field* field)
{
  return * (jshort *) field->u.addr;
}

inline jint
_Jv_GetStaticIntField (jclass, _Jv_Field* field)
{
  return * (jint *) field->u.addr;
}

inline jlong
_Jv_GetStaticLongField (jclass, _Jv_Field* field)
{
  return * (jlong *) field->u.addr;
}

inline jobject
_Jv_GetObjectField (jobject obj, _Jv_Field* field)
{
  return field->getObjectField (obj);
}

inline jbyte
_Jv_GetByteField (jobject obj, _Jv_Field* field)
{
  return * (jbyte *) ((char*) obj + field->getOffset ());
}

inline jshort
_Jv_GetShortField (jobject obj, _Jv_Field* field)
{
  return * (jshort *) ((char*) obj + field->getOffset ());
}
inline jint
_Jv_GetIntField (jobject obj, _Jv_Field* field)
{
  return * (jint *) ((char*) obj + field->getOffset ());
}
inline jlong
_Jv_GetLongField (jobject obj, _Jv_Field* field)
{
  return * (jlong *) ((char*) obj + field->getOffset ());
}

extern inline jfieldID 
_Jv_FromReflectedField (java::lang::reflect::Field *field)
{ 
  return (jfieldID) ((char *) field->declaringClass->fields + field->offset); 
} 


#ifdef __GCJ_CNI_H__
extern inline jfieldID
JvGetFirstInstanceField (jclass klass)
{
  return &(klass->fields[klass->static_field_count]);
}

extern inline jint
JvNumInstanceFields (jclass klass)
{
  return klass->field_count - klass->static_field_count;
}

extern inline jboolean
JvFieldIsRef (jfieldID field)
{
  return field->isRef ();
}

extern inline jobject
JvGetObjectField (jobject obj, _Jv_Field* field)
{
  return _Jv_GetObjectField (obj, field);
}
#endif /* defined (__GCJ_CNI_H__) */

#endif

#endif /* __GCJ_FIELD_H */
