/*

 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.

 * Use subject to license terms.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the

 * "Software"), to deal in the Software without restriction, including

 * without limitation the rights to use, copy, modify, merge, publish,

 * distribute, and/or sell copies of the Software, and to permit persons

 * to whom the Software is furnished to do so, provided that the above

 * copyright notice(s) and this permission notice appear in all copies of

 * the Software and that both the above copyright notice(s) and this

 * permission notice appear in supporting documentation.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT

 * OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR

 * HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL

 * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING

 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,

 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION

 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 * 

 * Except as contained in this notice, the name of a copyright holder

 * shall not be used in advertising or otherwise to promote the sale, use

 * or other dealings in this Software without prior written authorization

 * of the copyright holder.

 */

/*

 * winsysck - determine which window system protocols are available

 *

 * usage: winsysck [ -va ] [ -display display_name ] protocol [...]

 *

 * options:

 *   -a  check every protocol listed, rather than stopping after

 *       the first one.

 *   -v  print the first available protocol (or every available

 *       protocol, with the -a option) to stdout.

 *   -display display_name

 *       use the display display_name for X11 connections instead of

 *	 the one specified by the $DISPLAY environment variable.

 *   -timeout seconds

 *       The timeout option sets the number  of  seconds  before

 *       the winsysck will time out. 

 *

 * protocols:

 *   x11

 *       The X11 protocol.

 *   news

 *       The NeWS protocol.

 *   x11news

 *       Both the X11 and the NeWS protocols, and both connect to

 *       the same server.

 *   sunview

 *       The SunView protocol.

 *

 * NOTE: Since news, x11news, and sunview have been unsupported for over

 * a decade, we no longer actually check for them, but always return false.

 *

 * exit status:

 *    0  if any listed protocols are available

 *    1  if no listed protocols are available

 *    2  usage error

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/types.h>

#include <sys/time.h>

#include <signal.h>

#include <unistd.h>

static char* cmdname;

static void

usage () {

    fprintf(stderr, "usage: %s %s\n\t%s\n", cmdname,

	    "[-va] [-display display_name] [-timeout seconds] protocol [...]",

	    "protocol can be one of: x11 news x11news sunview");

    exit(2);

}

/*

 * Keep track of what protocols we're checking, and in what order.

 */

#define PROTO_NONE	0

#define PROTO_X11	1

#define PROTO_NeWS	2

#define PROTO_X11NeWS	3

#define PROTO_SunView	4

#define N_PROTO		4

static int proto_list[N_PROTO], n_proto;

static void

AddProto(int proto)

{

    int i;

    for (i=0; i<N_PROTO; i++) {

	if (proto_list[i]==proto) {

	    return;

	}

    }

    proto_list[n_proto++]=proto;

}

/*

 * Keep track of the options specified.

 */

static int verbose, showall, timeout = 0;

static char* display_name=NULL;

/*

 * Parse the options.

 */

static void

Parse (int argc, char* argv[])

{

    for (;argc > 1; argv++, argc--) {

	if (argv[1][0] == '-') {

	    if (!strcmp(argv[1], "-display")) {

		display_name=argv[2];

		argv++;

		argc--;

		continue;

	    }

	    if (!strcmp(argv[1], "-timeout")) {

                timeout = atoi(argv[2]);

                argv++;

                argc--;

                continue;

            } 

	    for (; argv[1][1]; argv[1]++) {

	        switch (argv[1][1]) {

	        case 'a':

		    showall++;

		    break;

		case 'v':

		    verbose++;

		    break;

		default:

		    fprintf(stderr, "%s: -%c: unknown option\n",

			    cmdname,argv[1][1]);

		    usage();

	        }

	    }

	}

	else {

	    if (!strcmp(argv[1], "x11")) {

		AddProto(PROTO_X11);

	    } else if (!strcmp(argv[1], "news")) {

		AddProto(PROTO_NeWS);

	    } else if (!strcmp(argv[1], "x11news")) {

		AddProto(PROTO_X11NeWS);

	    } else if (!strcmp(argv[1], "sunview")) {

		AddProto(PROTO_SunView);

	    } else {

		fprintf(stderr, "%s: %s: unknown protocol\n",

			cmdname,argv[1]);

		usage();

	    }

	}

    }

    if (!n_proto) {

	fprintf(stderr, "%s: no protocols specified\n",

		cmdname);

	usage();

    }

}

/* Last remnants of x11-procs.c */

#include <X11/Xlib.h>

#include <X11/Xos.h>

static Display *display=NULL;

static void OnAlarm(int i)

{

      fprintf(stderr, "winsysck timeout\n");

      exit(1);        

}

static int

ConnectToX (const char* display_name)

{

     if(timeout > 0){

       signal(SIGALRM, OnAlarm);

       alarm(timeout);

     }

     display=XOpenDisplay(display_name);

     if(timeout > 0)

       alarm(0);

     return((display != NULL));

}

static int

DisconnectFromX (void) {

    XCloseDisplay(display);

    return(1);

}

/*

 * Try connecting via the specified protocols.

 */

static void

Probe(void)

{

    int i, found=0;

    for(i=0; (i < N_PROTO) && (proto_list[i] != PROTO_NONE); i++) {

	switch (proto_list[i]) {

	case PROTO_X11:

	    if (ConnectToX(display_name)) {

		found++;

		if (verbose) printf("%s\n","x11");

	        DisconnectFromX();

		if (!showall) exit(0);

	    }

	    break;

	case PROTO_NeWS:

	case PROTO_X11NeWS:

	case PROTO_SunView:

	    /* Don't even bother */

	    break;

	default:

	    fprintf(stderr, "%s: WSGO: proto_list[%d]==%d\n",

		    cmdname,i,proto_list[i]);

	}

    }

    exit(!found);

}

int

main (int argc, char* argv[])

{

    cmdname=argv[0];

    Parse(argc,argv);

    Probe();

    exit(0);

}