/* Copyright (C) 1993, 1994, 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.
*/

/*$RCSfile: iutil2.c,v $ $Revision: 1.2.2.2 $ */
/* Level 2 utilities for Ghostscript interpreter */
#include "memory_.h"
#include "string_.h"
#include "ghost.h"
#include "errors.h"
#include "opcheck.h"
#include "gsparam.h"
#include "gsutil.h"		/* bytes_compare prototype */
#include "idict.h"
#include "imemory.h"		/* for iutil.h */
#include "iutil.h"
#include "iutil2.h"

/* ------ Password utilities ------ */

/* Read a password from a parameter list. */
/* Return 0 if present, 1 if absent, or an error code. */
int
param_read_password(gs_param_list * plist, const char *kstr, password * ppass)
{
    gs_param_string ps;
    long ipass;
    int code;

    ps.data = (const byte *)ppass->data, ps.size = ppass->size,
	ps.persistent = false;
    code = param_read_string(plist, kstr, &ps);
    switch (code) {
	case 0:		/* OK */
	    if (ps.size > MAX_PASSWORD)
		return_error(e_limitcheck);
	    /* Copy the data back. */
	    memcpy(ppass->data, ps.data, ps.size);
	    ppass->size = ps.size;
	    return 0;
	case 1:		/* key is missing */
	    return 1;
    }
    /* We might have gotten a typecheck because */
    /* the supplied password was an integer. */
    if (code != e_typecheck)
	return code;
    code = param_read_long(plist, kstr, &ipass);
    if (code != 0)		/* error or missing */
	return code;
    sprintf((char *)ppass->data, "%ld", ipass);
    ppass->size = strlen((char *)ppass->data);
    return 0;
}
/* Write a password to a parameter list. */
int
param_write_password(gs_param_list * plist, const char *kstr,
		     const password * ppass)
{
    gs_param_string ps;

    ps.data = (const byte *)ppass->data, ps.size = ppass->size,
	ps.persistent = false;
    if (ps.size > MAX_PASSWORD)
	return_error(e_limitcheck);
    return param_write_string(plist, kstr, &ps);
}

/* Check a password from a parameter list. */
/* Return 0 if OK, 1 if not OK, or an error code. */
int
param_check_password(gs_param_list * plist, const password * ppass)
{
    if (ppass->size != 0) {
	password pass;
	int code = param_read_password(plist, "Password", &pass);

	if (code)
	    return code;
	if (pass.size != ppass->size ||
	    bytes_compare(&pass.data[0], pass.size,
			  &ppass->data[0],
			  ppass->size) != 0
	    )
	    return 1;
    }
    return 0;
}

/* Read a password from, or write a password into, a dictionary */
/* (presumably systemdict). */
private int
dict_find_password(ref ** ppvalue, const ref * pdref, const char *kstr)
{
    ref *pvalue;

    if (dict_find_string(pdref, kstr, &pvalue) <= 0)
	return_error(e_undefined);
    if (!r_has_type(pvalue, t_string) ||
	r_has_attrs(pvalue, a_read) ||
	pvalue->value.const_bytes[0] >= r_size(pvalue)
	)
	return_error(e_rangecheck);
    *ppvalue = pvalue;
    return 0;
}
int
dict_read_password(password * ppass, const ref * pdref, const char *pkey)
{
    ref *pvalue;
    int code = dict_find_password(&pvalue, pdref, pkey);

    if (code < 0)
	return code;
    if (pvalue->value.const_bytes[0] > MAX_PASSWORD)
	return_error(e_rangecheck);	/* limitcheck? */
    memcpy(ppass->data, pvalue->value.const_bytes + 1,
	   (ppass->size = pvalue->value.const_bytes[0]));
    return 0;
}
int
dict_write_password(const password * ppass, ref * pdref, const char *pkey,
			bool change_allowed)
{
    ref *pvalue;
    int code = dict_find_password(&pvalue, pdref, pkey);

    if (code < 0)
	return code;
    if (ppass->size >= r_size(pvalue))
	return_error(e_rangecheck);
    if (!change_allowed &&
    	bytes_compare(pvalue->value.bytes + 1, pvalue->value.bytes[0],
	    ppass->data, ppass->size) != 0)
	return_error(e_invalidaccess);
    memcpy(pvalue->value.bytes + 1, ppass->data,
	   (pvalue->value.bytes[0] = ppass->size));
    return 0;
}
