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/* Copyright (C) 1994-2003 Revolution Software Ltd
*
* 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.
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* $Header$
*/
//=============================================================================
//
// Filename : keyboard.c
// Created : 19th September 1996
// By : P.R.Porter
//
// Summary : This module holds the interface to the keyboard
//
// Functions
// ---------
//
// --------------------------------------------------------------------------
//
// BOOL KeyWaiting(void)
//
// This function returns TRUE if there is an unprocessed key waiting in the
// queue, FALSE otherwise.
//
// --------------------------------------------------------------------------
//
// int32 ReadKey(char *key)
//
// Sets the value of key passed in to the current waiting key. If there is
// no key waiting, an error code is returned.
//
// --------------------------------------------------------------------------
//
// void GetKeyStatus(_drvKeyStatus *s)
//
// Retrieves the status of the keyboard handler.
//
//=============================================================================
#include "stdafx.h"
#include "driver96.h"
uint8 keyBacklog = 0; // The number of key presses waiting to be processed.
uint8 keyPointer = 0; // Index of the next key to read from the buffer.
_keyboardEvent keyBuffer[MAX_KEY_BUFFER]; // The keyboard buffer
void WriteKey(uint16 ascii, int keycode, int modifiers) {
if (keyBuffer && keyBacklog < MAX_KEY_BUFFER) {
_keyboardEvent *slot = &keyBuffer[(keyPointer + keyBacklog) % MAX_KEY_BUFFER];
slot->ascii = ascii;
slot->keycode = keycode;
slot->modifiers = modifiers;
keyBacklog++;
}
}
bool KeyWaiting(void) {
return keyBacklog != 0;
}
int32 ReadKey(_keyboardEvent *ev) {
if (!keyBacklog)
return RDERR_NOKEYWAITING;
if (ev == NULL)
return RDERR_INVALIDPOINTER;
ev->ascii = keyBuffer[keyPointer].ascii;
ev->keycode = keyBuffer[keyPointer].keycode;
ev->modifiers = keyBuffer[keyPointer].modifiers;
keyPointer++;
if (keyPointer == MAX_KEY_BUFFER)
keyPointer = 0;
keyBacklog--;
return RD_OK;
}
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