/******************************************************************************
*
*  (c) Copyright 1998, University of Karlstad.
*
*  This program is free software; you can redistribute it and/or modify it
*  under the terms of the GNU General Public License as published by
*  the Free Software Foundation; either version 1, or (at your option)
*  any later version.
*
*  This program 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 for more details.
*
*  You should have received a copy of the GNU General Public License
*  along with this program; if not, write to the Free Software
*  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*  Please report any bugs you find in this code or any improvements to:
*
*  Hans Hedbom, Dept. of Computer Science,
*  University of Karlstad, Sweden.
*
*  Phone: +46 54 838157
*  E-mail: Hans.Hedbom@hks.se
*
*  ============================================================================
*
*  FILE:
*
*  udefs.h [ the Data Communication I course programming project ]
*
*  AUTHORS:
*
*  Jonny Wiederholm
*  E-mail: fr7wied@cse.hks.se
*
*  Per-Ola Gustafsson
*  E-mail: fr7gust@cse.hks.se
*
*  CREATION DATE:
*
*  Jan, 06, 1998
*
*  DESCRIPTION:
*
*  Includes constants used in the example implementation of the Data
*  Communication I course programming project.
*
*  MODIFICATIONS:   Date    Changes
*  ----------------------------------------------------------------------------
*
*/

#ifndef _UDEFS_H    /* Avoid multiple copies of this file. */
#define _UDEFS_H

#ifdef __cplusplus  /* Make this file possible to use in C++ code. */
extern "C" {
#endif

/******************************************************************************
*  INCLUDE FILES
*/

#include "systems.h"

/******************************************************************************
*  DEFINE CONSTANTS
*/

/* Null pointer value. */
#ifndef NULL                  /* Avoid type redeclaration. */
#if !defined( __cplusplus) && !defined (sun)

#define NULL   ((void *) 0)

#else                   /* !defined( __cplusplus) && !defined (sun) */

#define NULL   0  /* C++ definition of NULL. */

#endif                  /* ifndef __cplusplus */
#endif                  /* ifndef NULL */

/* Normal exit value. */
#define NORMAL_EXIT  1

/* Non normal exit value. */
#define NON_NORMAL_EXIT  -1

/* End of string. */
#define EOS  '\0'

/* Value returned on the occurence of a system failure. */
#ifndef SYSTEM_FAILURE        /* Avoid type redeclaration. */
#define SYSTEM_FAILURE  (-1)
#endif

/* Value returned on a successful operation. */
#ifndef SUCCESS               /* Avoid type redeclaration. */
#define SUCCESS          0
#endif

/* Allow ANSI C keywords if ANSI C or C++. */
#if defined (__STDC__) || defined (__cplusplus)

#define const__     const
#define volatile__  volatile
/* Pointer to void is defined as pointer to char on non ANSI C systems. */
#define void_ptr_   void *

#else                   /* defined (__STDC__) || defined (__cplusplus) */

#define const__         /* No ANSI C keywords.  */
#define volatile__
#define void_ptr_   char *

#endif                  /* defined (__STDC__) || defined (__cplusplus) */

/******************************************************************************
*  DEFINE TYPES
*/

/* 
   `c_buf_ptr_' is used by functions which take a pointer to a character
   buffer as parameter and does not change the contents of the buffer.
   */
#ifndef C_BUF_PTR_             /* Avoid type redeclaration. */
#define C_BUF_PTR_
#if defined (__linux__)

typedef const__ char *  c_buf_ptr_;

#else                   /* defined (__linux__) */

typedef char *  c_buf_ptr_;

#endif                  /* defined (__linux__) */
#endif

/*
   `buf_ptr' is used by functions which take a pointer to a character
   buffer and does change the value of the buffer.
   */
#ifndef BUF_PTR_              /* Avoid type redeclaration. */
#define BUF_PTR_
typedef char * buf_ptr_;
#endif

/*
   `string_ptr_' is used by functions which take a pointer to a character
   string as parameter and does not change the contents of the string.
*/
#ifndef STRING_PTR_            /* Avoid type redeclaration. */
#define STRING_PTR_
typedef c_buf_ptr_  string_ptr_;
#endif

/*
   `byte_ptr_' is used by functions which takes a pointer to a character-buffer
   which only needs to store one character, or byte.
   */
#ifndef BYTE_PTR_
#define BYTE_PTR_
typedef char * byte_ptr_;
#endif

/* `size_t_' is used as a length parameter for string functions. */
#ifndef SIZE_T_                /* Avoid type redeclaration. */
#define SIZE_T_
typedef unsigned int  size_t_;
#endif
   
/*
   `ssize_t_' is used by functions which return a count of bytes or an error
   indication.
   */
#ifndef SSIZE_T_               /* Avoid type redeclaration. */
#define SSIZE_T_
typedef signed int  ssize_t_;
#endif

/* 
   `u_int_' is used by functions which take or return an unsigned int that
   is not indicating a length.
   */
#ifndef U_INT_                 /* Avoid type redeclaration. */
#define U_INT_
typedef unsigned int  u_int_;
#endif

/* 
   `ul_int_' is used by functions which take or return an unsigned long int
   that is not indicating a length.
   */
#ifndef UL_INT_                /* Avoid type redeclaration. */
#define UL_INT_
typedef unsigned long int ul_int_;
#endif

/******************************************************************************
*  DEFINE MACROS
*/

/* Allow function prototypes. */
#if defined (__STDC__) || defined (__cplusplus)

#ifndef __P                    /* Avoid type redeclaration. */
#define __P(args)   args
#endif

#else                   /* defined (__STDC__) || defined (__cplusplus) */

#ifndef __P                    /* Avoid type redeclaration. */
#define __P(args)   ()  /* No prototypes.  */
#endif

#endif                  /* defined (__STDC__) || defined (__cplusplus) */

/******************************************************************************
*  END
*/

#ifdef __cplusplus
}
#endif

#endif                  /* _UDEFS_H */