/* -*-C-*-

 * Common library code for the GNU Emacs server and client.

 *

 * This file is part of GNU Emacs.

 *

 * Copying is permitted under those conditions described by the GNU

 * General Public License.

 *

 * Copyright (C) 1989 Free Software Foundation, Inc.

 *

 * Author: Andy Norman (ange@hplb.hpl.hp.com), based on

 * 'etc/server.c' and 'etc/emacsclient.c' from the 18.52 GNU

 * Emacs distribution.

 *

 * Please mail bugs and suggestions to the author at the above address.

 */

/* HISTORY

 * 11-Nov-1990                bristor@simba

 *    Added EOT stuff.

 */

/*

 * This file incorporates new features added by Bob Weiner <weiner@mot.com>,

 * Darrell Kindred <dkindred@cmu.edu> and Arup Mukherjee <arup@cmu.edu>.

 * Please see the note at the end of the README file for details.

 *

 * (If gnuserv came bundled with your emacs, the README file is probably

 * ../etc/gnuserv.README relative to the directory containing this file)

 */

#include <config.h>

#include <glibtop.h>

#include <glibtop/error.h>

#include <glibtop/gnuserv.h>

#include <fcntl.h>

#ifdef UNIX_DOMAIN_SOCKETS

static int connect_to_unix_server (void);

#endif

#ifdef INTERNET_DOMAIN_SOCKETS

static int connect_to_internet_server (const char *serverhost, u_short port);

#endif

/* On some systems, e.g. DGUX, inet_addr returns a 'struct in_addr'. */

#ifdef HAVE_BROKEN_INET_ADDR

#define IN_ADDR struct in_addr

#define NUMERIC_ADDR_ERROR (numeric_addr.s_addr == 0xffffffff)

#else

#if (LONGBITS > 32)

#define IN_ADDR unsigned int

#else

#define IN_ADDR unsigned long

#endif

#define NUMERIC_ADDR_ERROR (numeric_addr == (IN_ADDR) 0xffffffff)

#endif

#include <arpa/inet.h>

int

glibtop_make_connection (const char *hostarg, int portarg, int *s)

{

#ifdef INTERNET_DOMAIN_SOCKETS

	char *ptr;

	if (hostarg == NULL)

		hostarg = getenv ("LIBGTOP_HOST");

	if (portarg == 0 && (ptr = getenv ("LIBGTOP_PORT")) != NULL)

		portarg = atoi (ptr);

#endif

	if (hostarg != NULL) {

		/* hostname was given explicitly, via cmd line arg or

		 * LIBGTOP_HOST,  * so obey it. */

#ifdef UNIX_DOMAIN_SOCKETS

		if (!strcmp (hostarg, "unix")) {

			*s = connect_to_unix_server ();

			return (int) CONN_UNIX;

		}

#endif /* UNIX_DOMAIN_SOCKETS */

#ifdef INTERNET_DOMAIN_SOCKETS

		*s = connect_to_internet_server (hostarg, portarg);

		return (int) CONN_INTERNET;

#endif

	} else {

		/* no hostname given.  Use unix-domain/sysv-ipc, or *

		 * internet-domain connection to local host if they're not

		 * available. */

#if   defined(UNIX_DOMAIN_SOCKETS)

		*s = connect_to_unix_server ();

		return (int) CONN_UNIX;

#elif defined(INTERNET_DOMAIN_SOCKETS)

		{

			char localhost[HOSTNAMSZ];

			gethostname (localhost, HOSTNAMSZ);	/* use this

								 * host by

								 * default */

			*s = connect_to_internet_server (localhost, portarg);

			return (int) CONN_INTERNET;

		}

#endif /* IPC type */

	}

}

#if defined(INTERNET_DOMAIN_SOCKETS) || defined(UNIX_DOMAIN_SOCKETS)

/*

 * send_string -- send string to socket.

 */

#if 0

static void

send_string (s, msg)

     int s;

     const char *msg;

{

#if 0

	if (send (s, msg, strlen (msg), 0) < 0) {

		perror (progname);

		fprintf (stderr, "%s: unable to send\n", progname);

		exit (1);

	};			/* if */

#else

	int len, left = strlen (msg);

	while (left > 0) {

		if ((len = write (s, msg, min2 (left, GSERV_BUFSZ))) < 0) {

			/* XEmacs addition: robertl@arnet.com */

			if (errno == EPIPE) {

				return;

			}

			perror (progname);

			fprintf (stderr, "%s: unable to send\n", progname);

			exit (1);

		};		/* if */

		left -= len;

		msg += len;

	};			/* while */

#endif

}				/* send_string */

/*

 * read_line -- read a \n terminated line from a socket

 */

static int

read_line (int s, char *dest)

{

	int length;

	int offset = 0;

	char buffer[GSERV_BUFSZ + 1];

	while ((length = read (s, buffer + offset, 1) > 0) && buffer[offset] != '\n'

	       && buffer[offset] != EOT_CHR) {

		offset += length;

		if (offset >= GSERV_BUFSZ)

			break;

	}

	buffer[offset] = '\0';

	strcpy (dest, buffer);

	return 1;

}				/* read_line */

#endif

#endif /* INTERNET_DOMAIN_SOCKETS || UNIX_DOMAIN_SOCKETS */

#ifdef UNIX_DOMAIN_SOCKETS

/*

 * connect_to_unix_server -- establish connection with server process via a unix-

 * domain socket. Returns socket descriptor for server

 * if successful.

 */

static int

connect_to_unix_server (void)

{

	int s;			/* connected socket descriptor */

	struct sockaddr_un server;	/* for unix connections */

	if ((s = socket (AF_UNIX, SOCK_STREAM, 0)) < 0)

		glibtop_error_io ("unable to create socket");

	server.sun_family = AF_UNIX;

#ifdef HIDE_UNIX_SOCKET

	sprintf (server.sun_path, "/tmp/lgtddir%d/lgtd", (int) geteuid ());

#else /* HIDE_UNIX_SOCKET */

	sprintf (server.sun_path, "/tmp/lgtd%d", (int) geteuid ());

#endif /* HIDE_UNIX_SOCKET */

	if (connect (s, (struct sockaddr *)&server, strlen (server.sun_path) + 2) < 0)

		glibtop_error_io ("unable to connect to local");

	return (s);

}				/* connect_to_unix_server */

#endif /* UNIX_DOMAIN_SOCKETS */

#ifdef INTERNET_DOMAIN_SOCKETS

/*

 * internet_addr -- return the internet addr of the hostname or

 * internet address passed. Return -1 on error.

 */

long

glibtop_internet_addr (const char *host)

{

	struct hostent *hp;	/* pointer to host info for remote host */

	IN_ADDR numeric_addr;	/* host address */

	numeric_addr = inet_addr (host);

	if (!NUMERIC_ADDR_ERROR)

		return numeric_addr;

	else if ((hp = gethostbyname (host)) != NULL)

		return ((struct in_addr *) (hp->h_addr))->s_addr;

	else {

		glibtop_warn_io ("gethostbyname (%s)", host);

		return -1;

	}

}				/* glibtop_internet_addr  */

#ifdef AUTH_MAGIC_COOKIE

#include <X11/X.h>

#include <X11/Xauth.h>

static Xauth *server_xauth = NULL;

#endif

/*

 * connect_to_internet_server -- establish connection with server process via

 * an internet domain socket. Returns socket

 * descriptor for server if successful.

 */

static int

connect_to_internet_server (const char *serverhost, u_short port)

{

	int s;			/* connected socket descriptor */

	struct servent *sp;	/* pointer to service information */

	struct sockaddr_in peeraddr_in;		/* for peer socket address */

	char buf[512];		/* temporary buffer */

	/* clear out address structures */

	memset (&peeraddr_in, 0, sizeof (struct sockaddr_in));

	/* Set up the peer address to which we will connect. */

	peeraddr_in.sin_family = AF_INET;

	/* look up the server host's internet address */

	peeraddr_in.sin_addr.s_addr = glibtop_internet_addr (serverhost);

	if ((long) peeraddr_in.sin_addr.s_addr == -1)

		glibtop_error ("unable to find %s in /etc/hosts or from YP", serverhost);

	if (port == 0) {

		if ((sp = getservbyname ("gtopd", "tcp")) == NULL)

			peeraddr_in.sin_port = htons (DEFAULT_PORT + getuid ());

		else

			peeraddr_in.sin_port = sp->s_port;

	}

	/* if */

	else

		peeraddr_in.sin_port = htons (port);

	/* Create the socket. */

	if ((s = socket (AF_INET, SOCK_STREAM, 0)) == -1)

		glibtop_error_io ("unable to create socket");

	/* Try to connect to the remote server at the address * which was

	 * just built into peeraddr. */

	if (connect (s, (struct sockaddr *) &peeraddr_in,

		     sizeof (struct sockaddr_in)) == -1)

		  glibtop_error_io ("unable to connect to remote");

#ifdef AUTH_MAGIC_COOKIE

	/* send credentials using MIT-MAGIC-COOKIE-1 protocol */

	sprintf (buf, "%d", port);

	server_xauth =

		XauGetAuthByAddr (FamilyInternet,

				  sizeof (peeraddr_in.sin_addr.s_addr),

				  (char *) &peeraddr_in.sin_addr.s_addr,

				  strlen (buf), buf,

				  strlen (MCOOKIE_X_NAME), MCOOKIE_X_NAME);

	if (server_xauth && server_xauth->data) {

		sprintf (buf, "%s\n%d\n", MCOOKIE_NAME, server_xauth->data_length);

		write (s, buf, strlen (buf));

		write (s, server_xauth->data, server_xauth->data_length);

		return (s);

	}

#endif /* AUTH_MAGIC_COOKIE */

	sprintf (buf, "%s\n", DEFAUTH_NAME);

	write (s, buf, strlen (buf));

	return (s);

}				/* connect_to_internet_server */

#endif /* INTERNET_DOMAIN_SOCKETS */

#if defined(INTERNET_DOMAIN_SOCKETS) || defined(UNIX_DOMAIN_SOCKETS)

/*

 * disconnect_from_server -- inform the server that sending has finished, and wait for

 * its reply.

 */

#if 0

static void

disconnect_from_server (s, echo)

     int s;

     int echo;

{

#if 0

	char buffer[REPLYSIZ + 1];

#else

	char buffer[GSERV_BUFSZ + 1];

#endif

	int add_newline = 1;

	int length;

	send_string (s, EOT_STR);	/* make sure server gets string */

#if !defined (linux)  && !defined (_SCO_DS)

	/*

	 * shutdown is completely hozed under linux. If s is a unix domain socket,

	 * you'll get EOPNOTSUPP back from it. If s is an internet socket, you get

	 * a broken pipe when you try to read a bit later. The latter

	 * problem is fixed for linux versions >= 1.1.46, but the problem

	 * with unix sockets persists. Sigh.

	 */

	if (shutdown (s, 1) == -1) {

		perror (progname);

		fprintf (stderr, "%s: unable to shutdown socket\n", progname);

		exit (1);

	};			/* if */

#endif

#if 0

	while ((length = recv (s, buffer, REPLYSIZ, 0)) > 0) {

		buffer[length] = '\0';

		if (echo)

			fputs (buffer, stdout);

		add_newline = (buffer[length - 1] != '\n');

	};			/* while */

#else

	while ((length = read (s, buffer, GSERV_BUFSZ)) > 0 ||

	       (length == -1 && errno == EINTR)) {

		if (length) {

			buffer[length] = '\0';

			if (echo) {

				fputs (buffer, stdout);

				add_newline = (buffer[length - 1] != '\n');

			};	/* if */

		};		/* if */

	};			/* while */

#endif

	if (echo && add_newline)

		putchar ('\n');

	if (length < 0) {

		perror (progname);

		fprintf (stderr, "%s: unable to read the reply from the server\n", progname);

		exit (1);

	};			/* if */

}				/* disconnect_from_server */

#endif

#endif /* INTERNET_DOMAIN_SOCKETS || UNIX_DOMAIN_SOCKETS */