Source to src/m_cheat.c
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// $Id:$
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// 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 2
// of the License, 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.
//
// $Log:$
//
// DESCRIPTION:
// Cheat sequence checking.
//
//-----------------------------------------------------------------------------
static const char
rcsid[] = "$Id: m_cheat.c,v 1.1 1997/02/03 21:24:34 b1 Exp $";
#include "m_cheat.h"
//
// CHEAT SEQUENCE PACKAGE
//
static int firsttime = 1;
static unsigned char cheat_xlate_table[256];
//
// Called in st_stuff module, which handles the input.
// Returns a 1 if the cheat was successful, 0 if failed.
//
int
cht_CheckCheat
( cheatseq_t* cht,
char key )
{
int i;
int rc = 0;
if (firsttime)
{
firsttime = 0;
for (i=0;i<256;i++) cheat_xlate_table[i] = SCRAMBLE(i);
}
if (!cht->p)
cht->p = cht->sequence; // initialize if first time
if (*cht->p == 0)
*(cht->p++) = key;
else if
(cheat_xlate_table[(unsigned char)key] == *cht->p) cht->p++;
else
cht->p = cht->sequence;
if (*cht->p == 1)
cht->p++;
else if (*cht->p == 0xff) // end of sequence character
{
cht->p = cht->sequence;
rc = 1;
}
return rc;
}
void
cht_GetParam
( cheatseq_t* cht,
char* buffer )
{
unsigned char *p, c;
p = cht->sequence;
while (*(p++) != 1);
do
{
c = *p;
*(buffer++) = c;
*(p++) = 0;
}
while (c && *p!=0xff );
if (*p==0xff)
*buffer = 0;
}