/*

 * Copyright (c) 2015, 2015, Oracle and/or its affiliates. All rights reserved.

 * Copyright (c) 2015, 2015 SAP SE. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

// Encapsulates the libodm library and provides more convenient interfaces.

#ifndef OS_AIX_VM_LIBODM_AIX_HPP

#define OS_AIX_VM_LIBODM_AIX_HPP

#include <odmi.h>

// The purpose of this code is to dynamically load the libodm library

// instead of statically linking against it. The library is AIX-specific.

// It only exists on AIX, not on PASE. In order to share binaries

// between AIX and PASE, we can't directly link against it.

typedef int          (*fun_odm_initialize )(void);

typedef char*        (*fun_odm_set_path   )(char*);

typedef CLASS_SYMBOL (*fun_odm_mount_class)(char*);

typedef void*        (*fun_odm_get_obj    )(CLASS_SYMBOL, char*, void*, int);

typedef int          (*fun_odm_terminate  )(void);

class dynamicOdm {

  void *_libhandle;

 protected:

  fun_odm_initialize  _odm_initialize;

  fun_odm_set_path    _odm_set_path;

  fun_odm_mount_class _odm_mount_class;

  fun_odm_get_obj     _odm_get_obj;

  fun_odm_terminate   _odm_terminate;

 public:

  dynamicOdm();

  ~dynamicOdm();

  bool odm_loaded() {return _libhandle != NULL; }

};

// We provide a more convenient interface for odm access and

// especially to determine the exact AIX kernel version.

class odmWrapper : private dynamicOdm {

  CLASS_SYMBOL _odm_class;

  char *_data;

  bool _initialized;

  void clean_data();

 public:

  // Make sure everything gets initialized and cleaned up properly.

  explicit odmWrapper(char* odm_class_name, char* odm_path = NULL) : _odm_class((CLASS_SYMBOL)-1),

                                                                     _data(NULL), _initialized(false) {

    if (!odm_loaded()) { return; }

    _initialized = ((*_odm_initialize)() != -1);

    if (_initialized) {

      if (odm_path) { (*_odm_set_path)(odm_path); }

      _odm_class = (*_odm_mount_class)(odm_class_name);

    }

  }

  ~odmWrapper() {

    if (_initialized) { (*_odm_terminate)(); clean_data(); }

  }

  CLASS_SYMBOL odm_class() { return _odm_class; }

  bool has_class() { return odm_class() != (CLASS_SYMBOL)-1; }

  int class_offset(char *field, bool is_aix_5);

  char* data() { return _data; }

  char* retrieve_obj(char* name = NULL) {

    clean_data();

    char *cnp = (char*)(void*)(*_odm_get_obj)(odm_class(), name, NULL, (name == NULL) ? ODM_NEXT : ODM_FIRST);

    if (cnp != (char*)-1) { _data = cnp; }

    return data();

  }

  int read_short(int offs) {

    short *addr = (short*)(data() + offs);

    return *addr;

  }

  // Determine the exact AIX kernel version as 4 byte value.

  // The high order 2 bytes must be initialized already. They can be determined by uname.

  static void determine_os_kernel_version(uint32_t* p_ver);

};

#endif // OS_AIX_VM_LIBODM_AIX_HPP