/* Copyright (C) 1990, 1995, 1997, 1998 Aladdin Enterprises.  All rights reserved.
  
  This file is part of GNU Ghostscript.
  
  GNU Ghostscript is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY.  No author or distributor accepts responsibility
  to anyone for the consequences of using it or for whether it serves any
  particular purpose or works at all, unless he says so in writing.  Refer
  to the GNU General Public License for full details.
  
  Everyone is granted permission to copy, modify and redistribute GNU
  Ghostscript, but only under the conditions described in the GNU General
  Public License.  A copy of this license is supposed to have been given
  to you along with GNU Ghostscript so you can know your rights and
  responsibilities.  It should be in a file named COPYING.  Among other
  things, the copyright notice and this notice must be preserved on all
  copies.
  
  Aladdin Enterprises supports the work of the GNU Project, but is not
  affiliated with the Free Software Foundation or the GNU Project.  GNU
  Ghostscript, as distributed by Aladdin Enterprises, does not require any
  GNU software to build or run it.
*/

/*$Id: zbseq.c $ */
/* Level 2 binary object sequence operators */
#include "memory_.h"
#include "ghost.h"
#include "oper.h"
#include "ialloc.h"
#include "btoken.h"
#include "store.h"

/* Current binary format (in iscan.c) */
extern ref ref_binary_object_format;

/* System and user name arrays. */
ref binary_token_names;		/* array of size 2 */
private ref *const binary_token_names_p = &binary_token_names;

/* Import the Level 2 scanner extensions. */
typedef struct scanner_state_s scanner_state;
extern int scan_binary_token(P3(stream *, ref *, scanner_state *));
extern int (*scan_btoken_proc) (P3(stream *, ref *, scanner_state *));

/* Initialize the binary token machinery. */
private void
zbseq_init(void)
{
    /* Initialize fake system and user name tables. */
    /* PostScript code will install the real system name table. */
    ialloc_ref_array(&binary_token_names, 0 /*a_noaccess */ , 2,
		     "binary token names");
    make_empty_array(system_names_p, a_readonly);
    make_empty_array(user_names_p, a_all);
    gs_register_ref_root(imemory, NULL, (void **)&binary_token_names_p,
			 "binary token names");

    /* Set up Level 2 scanning constants. */
    scan_btoken_proc = scan_binary_token;
}

/* <names> .installsystemnames - */
private int
zinstallsystemnames(register os_ptr op)
{
    if (r_space(op) != avm_global)
	return_error(e_invalidaccess);
    check_read_type(*op, t_shortarray);
    ref_assign_old(NULL, system_names_p, op, ".installsystemnames");
    pop(1);
    return 0;
}

/* - currentobjectformat <int> */
private int
zcurrentobjectformat(register os_ptr op)
{
    push(1);
    *op = ref_binary_object_format;
    return 0;
}

/* <int> setobjectformat - */
private int
zsetobjectformat(register os_ptr op)
{
    check_type(*op, t_integer);
    if (op->value.intval < 0 || op->value.intval > 4)
	return_error(e_rangecheck);
    ref_assign_old(NULL, &ref_binary_object_format, op, "setobjectformat");
    pop(1);
    return 0;
}

/* <ref_offset> <char_offset> <obj> <string8> .bosobject */
/*   <ref_offset'> <char_offset'> <string8> */
/*
 * This converts a single object to its binary object sequence
 * representation, doing the dirty work of printobject and writeobject.
 * (The main control is in PostScript code, so that we don't have to worry
 * about interrupts or callouts in the middle of writing the various data
 * items.)  Note that this may or may not modify the 'unused' field.
 */

private int
zbosobject(os_ptr op)
{
    int code;

    check_type(op[-3], t_integer);
    check_type(op[-2], t_integer);
    check_write_type(*op, t_string);
    if (r_size(op) < 8)
	return_error(e_rangecheck);
    code = encode_binary_token(op - 1, &op[-3].value.intval,
			       &op[-2].value.intval, op->value.bytes);
    if (code < 0)
	return code;
    op[-1] = *op;
    r_set_size(op - 1, 8);
    pop(1);
    return 0;
}

/* ------ Initialization procedure ------ */

const op_def zbseq_l2_op_defs[] =
{
    op_def_begin_level2(),
    {"1.installsystemnames", zinstallsystemnames},
    {"0currentobjectformat", zcurrentobjectformat},
    {"1setobjectformat", zsetobjectformat},
    {"4.bosobject", zbosobject},
    op_def_end(zbseq_init)
};
