/*
 *	PROGRAM:	Interprocess Interface definitions
 *  MODULE:		xnet.h
 *	DESCRIPTION:	Interprocess Server Communications module.
 *
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 *
 * 2003.05.01 Victor Seryodkin, Dmitry Yemanov: Completed XNET implementation
 */

#ifndef REMOTE_XNET_H
#define REMOTE_XNET_H

#ifndef WIN_NT
#include <sys/types.h>
#define PID_T	pid_t
#define CADDR_T	caddr_t
#define FILE_ID	int
#else
#define PID_T  	DWORD
#define CADDR_T	LPVOID
#define FILE_ID	HANDLE
#endif

// Client connect timeout (ms)
const DWORD XNET_CONNECT_TIMEOUT	= 10000;

// Receive wait timeout (ms)
const DWORD XNET_RECV_WAIT_TIMEOUT	= 500;

// Send wait timeout (ms)
const DWORD XNET_SEND_WAIT_TIMEOUT	= XNET_RECV_WAIT_TIMEOUT;

// Mapped file parameters

#define XPS_MAPPED_PER_CLI(p)			((ULONG)(p) * 1024L)
#define XPS_SLOT_OFFSET(pages, slot)	(XPS_MAPPED_PER_CLI(pages) * (ULONG)(slot))
#define XPS_MAPPED_SIZE(users, pages)	((ULONG)(users) * XPS_MAPPED_PER_CLI(pages))

#define XPS_USEFUL_SPACE(p)				(XPS_MAPPED_PER_CLI(p) - sizeof(struct xps))

const ULONG XPS_DEF_NUM_CLI			= 10;	// default clients per mapped file
const ULONG XPS_DEF_PAGES_PER_CLI	= 8;	// default 1K pages space per client

const ULONG XPS_MAX_NUM_CLI			= 64;	// max clients per mapped file
const ULONG XPS_MAX_PAGES_PER_CLI	= 16;	// max 1K pages space per client

const ULONG XNET_INVALID_MAP_NUM	= 0xFFFFFFFF;

const ULONG XNET_EVENT_SPACE		= 100;	// half of space (bytes) for event handling per connection

// Mapped file structure

typedef struct xpm
{
    struct xpm  *xpm_next;					// pointer to next one
    ULONG       xpm_count;					// slots in use
    ULONG       xpm_number;					// mapped area number
    FILE_ID     xpm_handle;					// handle of mapped memory
    USHORT      xpm_flags;					// flag word
    CADDR_T     xpm_address;				// address of mapped memory
    UCHAR       xpm_ids[XPS_MAX_NUM_CLI];	// ids
    ULONG       xpm_timestamp;				// timestamp to avoid map name conflicts
} *XPM;

// Mapped structure flags

const USHORT XPMF_SERVER_SHUTDOWN	= 1;	// server has shut down

// Mapped structure ids

const USHORT XPM_FREE				= 0;	// xpm structure is free for use
const USHORT XPM_BUSY				= 1;	// xpm structure is in use

// Comm channel structure - four per connection (client to server data,
// server to client data, client to server events, server to client events)

typedef struct xch
{
    ULONG		xch_length;					// message length
    ULONG		xch_size;					// channel data size
    USHORT		xch_flags;					// flags
	ULONG		xch_dummy1;					// for binary compatibility
	ULONG		xch_dummy2;					// with 32-bit builds
} *XCH;

// Thread connection control block

typedef struct xcc
{
    struct xcc  *xcc_next;					// pointer to next thread
    XPM         xcc_xpm;					// pointer back to xpm
    ULONG       xcc_map_num;				// this thread's mapped file number
    ULONG       xcc_slot;					// this thread's slot number
    FILE_ID     xcc_map_handle;				// mapped file's handle
#ifdef WIN_NT
    HANDLE      xcc_proc_h;					// for server - client's process handle,
		                                    // for client - server's process handle

    HANDLE      xcc_event_send_channel_filled; // xcc_send_channel ready for reading
    HANDLE      xcc_event_send_channel_empted; // xcc_send_channel ready for writting
    HANDLE      xcc_event_recv_channel_filled; // xcc_receive_channel ready for reading
    HANDLE      xcc_event_recv_channel_empted; // xcc_receive_channel ready for writing
#endif
    XCH         xcc_recv_channel;			// receive channel structure
    XCH         xcc_send_channel;			// send channel structure
    ULONG       xcc_flags;					// status bits
    UCHAR       *xcc_mapped_addr;			// where the thread is mapped to
} *XCC;

// XCC structure flags

const ULONG XCCF_SERVER_SHUTDOWN	= 1;	// server has shutdown detected

// This structure (xps) is mapped to the start of the allocated
// communications area between the client and server

typedef struct xps
{
    ULONG       xps_server_protocol;		// server's protocol level
    ULONG       xps_client_protocol;		// client's protocol level
    PID_T       xps_server_proc_id;			// server's process id
    PID_T       xps_client_proc_id;			// client's process id
    USHORT      xps_flags;					// flags word
    struct xch  xps_channels[4];			// comm channels
    ULONG       xps_data[1];				// start of data area
} *XPS;

// XPS flags

const USHORT XPS_DISCONNECTED = 1;

// xps_channel numbers

const int XPS_CHANNEL_C2S_DATA		= 0;	// 0 - client to server data
const int XPS_CHANNEL_S2C_DATA		= 1;	// 1 - server to client data
const int XPS_CHANNEL_C2S_EVENTS	= 2;	// 2 - client to server events
const int XPS_CHANNEL_S2C_EVENTS	= 3;	// 3 - server to client events

const ULONG XPI_CLIENT_PROTOCOL_VERSION		= 3;
const ULONG XPI_SERVER_PROTOCOL_VERSION		= 3;

// XNET_RESPONSE - server response on client connect request

struct XNET_RESPONSE
{
	ULONG proc_id;
	ULONG slots_per_map;
	ULONG pages_per_slot;
	ULONG map_num;
	ULONG slot_num;
	ULONG timestamp;
};

// XNET_CONNECT_RESPONZE_SIZE - amount of bytes server writes on connect response

const size_t XNET_CONNECT_RESPONZE_SIZE	= sizeof(XNET_RESPONSE);

// Windows names used to identify various named objects

const char* XNET_MAPPED_FILE_NAME		= "%s_MAP_%"ULONGFORMAT"_%"ULONGFORMAT;

const char* XNET_CONNECT_MAP			= "%s_CONNECT_MAP";
const char* XNET_CONNECT_MUTEX			= "%s_CONNECT_MUTEX";
const char* XNET_CONNECT_EVENT			= "%s_CONNECT_EVENT";
const char* XNET_RESPONSE_EVENT			= "%s_RESPONSE_EVENT";

const char* XNET_E_C2S_DATA_CHAN_FILLED	= "%s_E_C2S_DATA_FILLED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;
const char* XNET_E_C2S_DATA_CHAN_EMPTED	= "%s_E_C2S_DATA_EMPTED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;
const char* XNET_E_S2C_DATA_CHAN_FILLED	= "%s_E_S2C_DATA_FILLED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;
const char* XNET_E_S2C_DATA_CHAN_EMPTED	= "%s_E_S2C_DATA_EMPTED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;

const char* XNET_E_C2S_EVNT_CHAN_FILLED	= "%s_E_C2S_EVNT_FILLED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;
const char* XNET_E_C2S_EVNT_CHAN_EMPTED	= "%s_E_C2S_EVNT_EMPTED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;
const char* XNET_E_S2C_EVNT_CHAN_FILLED	= "%s_E_S2C_EVNT_FILLED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;
const char* XNET_E_S2C_EVNT_CHAN_EMPTED	= "%s_E_S2C_EVNT_EMPTED_%"ULONGFORMAT"_%"ULONGFORMAT"_%"ULONGFORMAT;

#endif // REMOTE_XNET_H