/*++
/* NAME
/*	tok822_node 3
/* SUMMARY
/*	token memory management
/* SYNOPSIS
/*	#include <tok822.h>
/*
/*	TOK822	*tok822_alloc(type, strval)
/*	int	type;
/*	const char *strval;
/*
/*	TOK822	*tok822_free(tp)
/*	TOK822	*tp;
/* DESCRIPTION
/*	This module implements memory management for token
/*	structures. A distinction is made between single-character
/*	tokens that have no string value, and string-valued tokens.
/*
/*	tok822_alloc() allocates memory for a token structure of
/*	the named type, and initializes it properly. In case of
/*	a single-character token, no string memory is allocated.
/*	Otherwise, \fIstrval\fR is a null pointer or provides
/*	string data to initialize the token with.
/*
/*	tok822_free() releases the memory used for the specified token
/*	and conveniently returns a null pointer value.
/* LICENSE
/* .ad
/* .fi
/*	The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*	Wietse Venema
/*	IBM T.J. Watson Research
/*	P.O. Box 704
/*	Yorktown Heights, NY 10598, USA
/*--*/

/* System library. */

#include <sys_defs.h>
#include <string.h>

/* Utility library. */

#include <mymalloc.h>
#include <vstring.h>

/* Global library. */

#include "tok822.h"

/* tok822_alloc - allocate and initialize token */

TOK822 *tok822_alloc(int type, const char *strval)
{
    TOK822 *tp;

#define CONTAINER_TOKEN(x) \
	((x) == TOK822_ADDR || (x) == TOK822_STARTGRP)

    tp = (TOK822 *) mymalloc(sizeof(*tp));
    tp->type = type;
    tp->next = tp->prev = tp->head = tp->tail = tp->owner = 0;
    tp->vstr = (type < TOK822_MINTOK || CONTAINER_TOKEN(type) ? 0 :
		strval == 0 ? vstring_alloc(10) :
		vstring_strcpy(vstring_alloc(strlen(strval) + 1), strval));
    return (tp);
}

/* tok822_free - destroy token */

TOK822 *tok822_free(TOK822 *tp)
{
    if (tp->vstr)
	vstring_free(tp->vstr);
    myfree((void *) tp);
    return (0);
}
