mc/vfs/mcfs.c

/* Virtual File System: Midnight Commander file system.
   
   Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
   2004, 2005, 2007 Free Software Foundation, Inc.

   Written by Miguel de Icaza
              Andrej Borsenkow
	      Norbert Warmuth
   
   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library 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 Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

/* Namespace: exports mcfs_vfs_ops, tcp_invalidate_socket */

#include <config.h>

#ifdef WITH_MCFS
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdarg.h>
#include <pwd.h>
#include <sys/types.h>		/* POSIX-required by sys/socket.h and netdb.h */
#include <netdb.h>		/* struct hostent */
#include <sys/socket.h>		/* AF_INET */
#include <netinet/in.h>		/* struct in_addr */
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif

#ifdef HAVE_PMAP_SET
#include <rpc/rpc.h>
#include <rpc/pmap_prot.h>
#ifdef HAVE_RPC_PMAP_CLNT_H
#include <rpc/pmap_clnt.h>
#endif
#endif

#include "../src/global.h"
#include "../src/tty.h"		/* enable/disable interrupt key */
#include "../src/wtools.h"	/* message() */
#include "../src/main.h"	/* print_vfs_message */
#include "utilvfs.h"
#include "vfs.h"
#include "vfs-impl.h"
#include "mcfs.h"
#include "mcfsutil.h"
#include "tcputil.h"

#ifndef INADDR_NONE
#  define INADDR_NONE (0xffffffffU)
#endif

#define MCFS_MAX_CONNECTIONS 32

static struct _mcfs_connection {
    char *host;
    char *user;
    char *home;
    int sock;
    int port;
    int version;
} mcfs_connections[MCFS_MAX_CONNECTIONS];


#define mcserver_port 9876

typedef struct _mcfs_connection mcfs_connection;

typedef struct {
    int handle;
    mcfs_connection *conn;
} mcfs_handle;

static char *mcfs_gethome (mcfs_connection * mc);
static int my_errno;
static struct vfs_class vfs_mcfs_ops;

/* Extract the hostname and username from the path */
/* path is in the form: hostname:user/remote-dir */
static char *
mcfs_get_host_and_username (const char *path, char **host, char **user,
			    int *port, char **pass)
{
    return vfs_split_url (path, host, user, port, pass, 0, 0);
}

static void
mcfs_fill_names (struct vfs_class *me, fill_names_f func)
{
    int i;
    char *name;

    (void) me;

    for (i = 0; i < MCFS_MAX_CONNECTIONS; i++) {
	if (mcfs_connections[i].host == 0)
	    continue;
	name = g_strconcat ("/#mc:", mcfs_connections[i].user,
			    "@", mcfs_connections[i].host, (char *) NULL);
	(*func) (name);
	g_free (name);
    }
}

/* This routine checks the server RPC version and logs the user in */
static int
mcfs_login_server (int my_socket, char *user, int port,
		   int port_autodetected, char *netrcpass, int *version)
{
    int result;
    char *pass;

    /* Send the version number */
    rpc_send (my_socket, RPC_INT, *version, RPC_END);
    if (0 == rpc_get (my_socket, RPC_INT, &result, RPC_END))
	return 0;

    if (result != MC_VERSION_OK) {
	message (D_ERROR, _(" MCFS "),
		    _(" The server does not support this version "));
	close (my_socket);
	return 0;
    }

    /* FIXME: figure out why last_current_dir used to be passed here */
    rpc_send (my_socket, RPC_INT, MC_LOGIN, RPC_STRING, "/",
	      RPC_STRING, user, RPC_END);

    if (0 == rpc_get (my_socket, RPC_INT, &result, RPC_END))
	return 0;

    if (result == MC_NEED_PASSWORD) {
	if (port > 1024 && port_autodetected) {
	    int v;
	    v = query_dialog (_("Warning"),
			      _
			      (" The remote server is not running on a system port \n"
			       " you need a password to log in, but the information may \n"
			       " not be safe on the remote side.  Continue? \n"),
			      D_ERROR, 2, _("&Yes"), _("&No"));

	    if (v == 1) {
		close (my_socket);
		return 0;
	    }
	}
	if (netrcpass != NULL)
	    pass = g_strdup (netrcpass);
	else
	    pass = vfs_get_password (_(" MCFS Password required "));
	if (!pass) {
	    rpc_send (my_socket, RPC_INT, MC_QUIT, RPC_END);
	    close (my_socket);
	    return 0;
	}
	rpc_send (my_socket, RPC_INT, MC_PASS, RPC_STRING, pass, RPC_END);

	wipe_password (pass);

	if (0 == rpc_get (my_socket, RPC_INT, &result, RPC_END))
	    return 0;

	if (result != MC_LOGINOK) {
	    message (D_ERROR, _(" MCFS "), _(" Invalid password "));
	    rpc_send (my_socket, RPC_INT, MC_QUIT, RPC_END);
	    close (my_socket);
	    return 0;
	}
    }
    return my_socket;
}

static int
mcfs_get_remote_port (struct sockaddr_in *sin, int *version)
{
#ifdef HAVE_PMAP_GETMAPS
    int port;
    struct pmaplist *pl;

    *version = 1;
    port = mcserver_port;
    for (pl = pmap_getmaps (sin); pl; pl = pl->pml_next)
	if (pl->pml_map.pm_prog == RPC_PROGNUM
	    && pl->pml_map.pm_prot == IPPROTO_TCP
	    && pl->pml_map.pm_vers >= (unsigned long) *version) {
	    *version = (int) pl->pml_map.pm_vers;
	    port = pl->pml_map.pm_port;
	}
    return port;
#else
#ifdef HAVE_PMAP_GETPORT
    int port;
    for (*version = RPC_PROGVER; *version >= 1; (*version)--)
	if (port = pmap_getport (sin, RPC_PROGNUM, *version, IPPROTO_TCP))
	    return port;
#endif				/* HAVE_PMAP_GETPORT */
    *version = 1;
    return mcserver_port;
#endif				/* HAVE_PMAP_GETMAPS */
}

/* This used to be in utilvfs.c, but as it deals with portmapper, it
   is probably useful for mcfs */
static int
mcfs_create_tcp_link (const char *host, int *port, int *version, const char *caller)
{
    struct sockaddr_in server_address;
    unsigned long inaddr;
    struct hostent *hp;
    int my_socket;

    if (!*host)
	return 0;

    memset ((char *) &server_address, 0, sizeof (server_address));
    server_address.sin_family = AF_INET;

    /*  Try to use the dotted decimal number */
    if ((inaddr = inet_addr (host)) != INADDR_NONE)
	memcpy ((char *) &server_address.sin_addr, (char *) &inaddr,
		sizeof (inaddr));
    else {
	if ((hp = gethostbyname (host)) == NULL) {
	    message (D_ERROR, caller, _(" Cannot locate hostname: %s "),
			host);
	    return 0;
	}
	memcpy ((char *) &server_address.sin_addr, (char *) hp->h_addr,
		hp->h_length);
    }

    /* Try to contact a remote portmapper to obtain the listening port */
    if (*port == 0) {
	*port = mcfs_get_remote_port (&server_address, version);
	if (*port < 1)
	    return 0;
    } else
	*version = 1;

    server_address.sin_port = htons (*port);

    if ((my_socket = socket (AF_INET, SOCK_STREAM, 0)) < 0) {
	message (D_ERROR, caller, _(" Cannot create socket: %s "),
		    unix_error_string (errno));
	return 0;
    }
    if (connect (my_socket, (struct sockaddr *) &server_address,
		 sizeof (server_address)) < 0) {
	message (D_ERROR, caller, _(" Cannot connect to server: %s "),
		    unix_error_string (errno));
	close (my_socket);
	return 0;
    }
    return my_socket;
}

static int
mcfs_open_tcp_link (char *host, char *user,
		    int *port, char *netrcpass, int *version)
{
    int my_socket;
    int old_port = *port;

    my_socket = mcfs_create_tcp_link (host, port, version, " MCfs ");
    if (my_socket <= 0)
	return 0;

    /* We got the connection to the server, verify if the server
       implements our version of the RPC mechanism and then login
       the user.
     */
    return mcfs_login_server (my_socket, user, *port, old_port == 0,
			      netrcpass, version);
}

static int mcfs_get_free_bucket_init = 1;
static mcfs_connection *
mcfs_get_free_bucket (void)
{
    int i;

    if (mcfs_get_free_bucket_init) {
	mcfs_get_free_bucket_init = 0;
	for (i = 0; i < MCFS_MAX_CONNECTIONS; i++)
	    mcfs_connections[i].host = 0;
    }
    for (i = 0; i < MCFS_MAX_CONNECTIONS; i++) {
	if (!mcfs_connections[i].host)
	    return &mcfs_connections[i];
    }
    /* This can't happend, since we have checked for max connections before */
    vfs_die ("Internal error: mcfs_get_free_bucket");
    return 0;			/* shut up, stupid gcc */
}

/* This routine keeps track of open connections */
/* Returns a connected socket to host */
static mcfs_connection *
mcfs_open_link (char *host, char *user, int *port, char *netrcpass)
{
    static int mcfs_open_connections = 0;
    int i, sock, version;
    mcfs_connection *bucket;

    /* Is the link actually open? */
    if (mcfs_get_free_bucket_init) {
	mcfs_get_free_bucket_init = 0;
	for (i = 0; i < MCFS_MAX_CONNECTIONS; i++)
	    mcfs_connections[i].host = 0;
    } else
	for (i = 0; i < MCFS_MAX_CONNECTIONS; i++) {
	    if (!mcfs_connections[i].host)
		continue;
	    if ((strcmp (host, mcfs_connections[i].host) == 0) &&
		(strcmp (user, mcfs_connections[i].user) == 0))
		return &mcfs_connections[i];
	}
    if (mcfs_open_connections == MCFS_MAX_CONNECTIONS) {
	message (D_ERROR, MSG_ERROR, _(" Too many open connections "));
	return 0;
    }

    if (!
	(sock =
	 mcfs_open_tcp_link (host, user, port, netrcpass, &version)))
	return 0;

    bucket = mcfs_get_free_bucket ();
    mcfs_open_connections++;
    bucket->host = g_strdup (host);
    bucket->user = g_strdup (user);
    bucket->home = 0;
    bucket->port = *port;
    bucket->sock = sock;
    bucket->version = version;

    return bucket;
}

static int
mcfs_is_error (int result, int errno_num)
{
    if (!(result == -1))
	return my_errno = 0;
    else
	my_errno = errno_num;
    return 1;
}

static int
mcfs_set_error (int result, int errno_num)
{
    if (result == -1)
	my_errno = errno_num;
    else
	my_errno = 0;
    return result;
}

static char *
mcfs_get_path (mcfs_connection **mc, const char *path)
{
    char *user, *host, *remote_path;
    char *pass;
    int port;

    /* An absolute path name, try to determine connection socket */
    if (strncmp (path, "/#mc:", 5))
	return NULL;
    path += 5;

    /* Port = 0 means that mcfs_create_tcp_link will try to contact the
     * remote portmapper to get the port number
     */
    port = 0;
    if ((remote_path =
	 mcfs_get_host_and_username (path, &host, &user, &port, &pass)))
	if (!(*mc = mcfs_open_link (host, user, &port, pass))) {
	    g_free (remote_path);
	    remote_path = NULL;
	}
    g_free (host);
    g_free (user);
    if (pass)
	wipe_password (pass);

    if (!remote_path)
	return NULL;

    /* NOTE: tildes are deprecated. See ftpfs.c */
    {
	int f = !strcmp (remote_path, "/~");
	if (f || !strncmp (remote_path, "/~/", 3)) {
	    char *s;
	    s = concat_dir_and_file (mcfs_gethome (*mc),
				     remote_path + 3 - f);
	    g_free (remote_path);
	    remote_path = s;
	}
    }
    return remote_path;
}

/* Simple function for routines returning only an integer from the server */
static int
mcfs_handle_simple_error (int sock, int return_status)
{
    int status, error;

    if (0 == rpc_get (sock, RPC_INT, &status, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, EIO);

    if (mcfs_is_error (status, error))
	return -1;
    if (return_status)
	return status;
    return 0;
}

/* Nice wrappers */
static int
mcfs_rpc_two_paths (int command, const char *s1, const char *s2)
{
    mcfs_connection *mc;
    char *r1, *r2;

    if ((r1 = mcfs_get_path (&mc, s1)) == 0)
	return -1;

    if ((r2 = mcfs_get_path (&mc, s2)) == 0) {
	g_free (r1);
	return -1;
    }

    rpc_send (mc->sock,
	      RPC_INT, command, RPC_STRING, r1, RPC_STRING, r2, RPC_END);
    g_free (r1);
    g_free (r2);
    return mcfs_handle_simple_error (mc->sock, 0);
}

static int
mcfs_rpc_path (int command, const char *path)
{
    mcfs_connection *mc;
    char *remote_file;

    if ((remote_file = mcfs_get_path (&mc, path)) == 0)
	return -1;

    rpc_send (mc->sock,
	      RPC_INT, command, RPC_STRING, remote_file, RPC_END);

    g_free (remote_file);
    return mcfs_handle_simple_error (mc->sock, 0);
}

static int
mcfs_rpc_path_int (int command, const char *path, int data)
{
    mcfs_connection *mc;
    char *remote_file;

    if ((remote_file = mcfs_get_path (&mc, path)) == 0)
	return -1;

    rpc_send (mc->sock,
	      RPC_INT, command,
	      RPC_STRING, remote_file, RPC_INT, data, RPC_END);

    g_free (remote_file);
    return mcfs_handle_simple_error (mc->sock, 0);
}

static int
mcfs_rpc_path_int_int (int command, const char *path, int n1, int n2)
{
    mcfs_connection *mc;
    char *remote_file;

    if ((remote_file = mcfs_get_path (&mc, path)) == 0)
	return -1;

    rpc_send (mc->sock,
	      RPC_INT, command,
	      RPC_STRING, remote_file, RPC_INT, n1, RPC_INT, n2, RPC_END);

    g_free (remote_file);
    return mcfs_handle_simple_error (mc->sock, 0);
}

static char *
mcfs_gethome (mcfs_connection *mc)
{
    char *buffer;

    if (mc->home)
	return g_strdup (mc->home);
    else {
	rpc_send (mc->sock, RPC_INT, MC_GETHOME, RPC_END);
	if (0 == rpc_get (mc->sock, RPC_STRING, &buffer, RPC_END))
	    return g_strdup (PATH_SEP_STR);
	mc->home = buffer;
	return g_strdup (buffer);
    }
}

/* The callbacks */
static void *
mcfs_open (struct vfs_class *me, const char *file, int flags, int mode)
{
    char *remote_file;
    mcfs_connection *mc;
    int result, error_num;
    mcfs_handle *remote_handle;

    (void) me;

    if (!(remote_file = mcfs_get_path (&mc, file)))
	return 0;

    rpc_send (mc->sock, RPC_INT, MC_OPEN, RPC_STRING, remote_file, RPC_INT,
	      flags, RPC_INT, mode, RPC_END);
    g_free (remote_file);

    if (0 ==
	rpc_get (mc->sock, RPC_INT, &result, RPC_INT, &error_num, RPC_END))
	return 0;

    if (mcfs_is_error (result, error_num))
	return 0;

    remote_handle = g_new (mcfs_handle, 2);
    remote_handle->handle = result;
    remote_handle->conn = mc;

    return remote_handle;
}

static ssize_t
mcfs_read (void *data, char *buffer, int count)
{
    mcfs_handle *info = (mcfs_handle *) data;
    int result, error;
    int handle;
    mcfs_connection *mc;

    mc = info->conn;
    handle = info->handle;

    rpc_send (mc->sock, RPC_INT, MC_READ, RPC_INT, handle,
	      RPC_INT, count, RPC_END);

    if (0 ==
	rpc_get (mc->sock, RPC_INT, &result, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, EIO);

    if (mcfs_is_error (result, error))
	return 0;

    if (0 == rpc_get (mc->sock, RPC_BLOCK, result, buffer, RPC_END))
	return mcfs_set_error (-1, EIO);

    return result;
}

static ssize_t
mcfs_write (void *data, const char *buf, int nbyte)
{
    mcfs_handle *info = (mcfs_handle *) data;
    mcfs_connection *mc;
    int handle;

    mc = info->conn;
    handle = info->handle;

    rpc_send (mc->sock,
	      RPC_INT, MC_WRITE,
	      RPC_INT, handle,
	      RPC_INT, nbyte, RPC_BLOCK, nbyte, buf, RPC_END);

    return mcfs_handle_simple_error (mc->sock, 1);
}

static int
mcfs_close (void *data)
{
    mcfs_handle *info = (mcfs_handle *) data;
    mcfs_connection *mc;
    int handle, result, error;

    if (!data)
	return -1;

    handle = info->handle;
    mc = info->conn;

    rpc_send (mc->sock, RPC_INT, MC_CLOSE, RPC_INT, handle, RPC_END);

    if (0 ==
	rpc_get (mc->sock, RPC_INT, &result, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, EIO);

    mcfs_is_error (result, error);

    g_free (data);
    return result;
}

static int
mcfs_errno (struct vfs_class *me)
{
    (void) me;

    return my_errno;
}

typedef struct dir_entry {
    char *text;
    struct dir_entry *next;
    struct stat my_stat;
    int merrno;
} dir_entry;

typedef struct {
    mcfs_connection *conn;
    int handle;
    dir_entry *entries;
    dir_entry *current;
} opendir_info;

static void *
mcfs_opendir (struct vfs_class *me, const char *dirname)
{
    opendir_info *mcfs_info;
    mcfs_connection *mc;
    int handle, error_num;
    char *remote_dir;
    int result;

    (void) me;

    if (!(remote_dir = mcfs_get_path (&mc, dirname)))
	return 0;

    rpc_send (mc->sock, RPC_INT, MC_OPENDIR, RPC_STRING, remote_dir,
	      RPC_END);
    g_free (remote_dir);

    if (0 ==
	rpc_get (mc->sock, RPC_INT, &result, RPC_INT, &error_num, RPC_END))
	return 0;

    if (mcfs_is_error (result, error_num))
	return 0;

    handle = result;

    mcfs_info = g_new (opendir_info, 1);
    mcfs_info->conn = mc;
    mcfs_info->handle = handle;
    mcfs_info->entries = 0;
    mcfs_info->current = 0;

    return mcfs_info;
}

static int mcfs_get_stat_info (mcfs_connection * mc, struct stat *buf);

static int
mcfs_loaddir (opendir_info *mcfs_info)
{
    int status, error;
    mcfs_connection *mc = mcfs_info->conn;
    int link = mc->sock;
    int first = 1;

    rpc_send (link, RPC_INT, MC_READDIR, RPC_INT, mcfs_info->handle,
	      RPC_END);

    for (;;) {
	int entry_len;
	dir_entry *new_entry;

	if (!rpc_get (link, RPC_INT, &entry_len, RPC_END))
	    return 0;

	if (entry_len == 0)
	    break;

	new_entry = g_new (dir_entry, 1);
	new_entry->text = g_new0 (char, entry_len + 1);

	new_entry->next = 0;
	if (first) {
	    mcfs_info->entries = new_entry;
	    mcfs_info->current = new_entry;
	    first = 0;
	} else {
	    mcfs_info->current->next = new_entry;
	    mcfs_info->current = new_entry;
	}

	if (!rpc_get
	    (link, RPC_BLOCK, entry_len, new_entry->text, RPC_END))
	    return 0;

	/* Then we get the status from the lstat */
	if (!rpc_get (link, RPC_INT, &status, RPC_INT, &error, RPC_END))
	    return 0;

	if (mcfs_is_error (status, error))
	    new_entry->merrno = error;
	else {
	    new_entry->merrno = 0;
	    if (!mcfs_get_stat_info (mc, &(new_entry->my_stat)))
		return 0;
	}
    }
    mcfs_info->current = mcfs_info->entries;

    return 1;
}

static void
mcfs_free_dir (dir_entry *de)
{
    if (!de)
	return;
    mcfs_free_dir (de->next);
    g_free (de->text);
    g_free (de);
}

static union vfs_dirent mcfs_readdir_data;

/* The readdir routine loads the complete directory */
/* It's too slow to ask the server each time */
/* It now also sends the complete lstat information for each file */
static struct stat *cached_lstat_info;

static void *
mcfs_readdir (void *info)
{
    opendir_info *mcfs_info;
    char *dirent_dest;

    mcfs_info = (opendir_info *) info;

    if (!mcfs_info->entries)
	if (!mcfs_loaddir (mcfs_info))
	    return NULL;

    if (mcfs_info->current == 0) {
	cached_lstat_info = 0;
	mcfs_free_dir (mcfs_info->entries);
	mcfs_info->entries = 0;
	return NULL;
    }
    dirent_dest = mcfs_readdir_data.dent.d_name;
    g_strlcpy (dirent_dest, mcfs_info->current->text, MC_MAXPATHLEN);
    cached_lstat_info = &mcfs_info->current->my_stat;
    mcfs_info->current = mcfs_info->current->next;

    compute_namelen (&mcfs_readdir_data.dent);

    return &mcfs_readdir_data;
}

static int
mcfs_closedir (void *info)
{
    opendir_info *mcfs_info = (opendir_info *) info;
    dir_entry *p, *q;

    rpc_send (mcfs_info->conn->sock, RPC_INT, MC_CLOSEDIR,
	      RPC_INT, mcfs_info->handle, RPC_END);

    for (p = mcfs_info->entries; p;) {
	q = p;
	p = p->next;
	g_free (q->text);
	g_free (q);
    }
    g_free (info);
    return 0;
}

static time_t
mcfs_get_time (mcfs_connection *mc)
{
    int sock = mc->sock;

    if (mc->version == 1) {
	struct tm tt;

	rpc_get (sock,
		 RPC_INT, &tt.tm_sec,
		 RPC_INT, &tt.tm_min,
		 RPC_INT, &tt.tm_hour,
		 RPC_INT, &tt.tm_mday,
		 RPC_INT, &tt.tm_year, RPC_INT, &tt.tm_mon, RPC_END);
	tt.tm_year -= 1900;
	tt.tm_isdst = 0;

	return mktime (&tt);
    } else {
	char *buf;
	long tm;

	rpc_get (sock, RPC_STRING, &buf, RPC_END);
	sscanf (buf, "%lx", &tm);
	g_free (buf);

	return (time_t) tm;
    }
}

static int
mcfs_get_stat_info (mcfs_connection *mc, struct stat *buf)
{
    long mylong;
    int sock = mc->sock;

    buf->st_dev = 0;

    rpc_get (sock, RPC_INT, &mylong, RPC_END);
#ifdef HAVE_STRUCT_STAT_ST_RDEV
    buf->st_rdev = mylong;
#endif
    rpc_get (sock, RPC_INT, &mylong, RPC_END);
    buf->st_ino = mylong;
    rpc_get (sock, RPC_INT, &mylong, RPC_END);
    buf->st_mode = mylong;
    rpc_get (sock, RPC_INT, &mylong, RPC_END);
    buf->st_nlink = mylong;
    rpc_get (sock, RPC_INT, &mylong, RPC_END);
    buf->st_uid = mylong;
    rpc_get (sock, RPC_INT, &mylong, RPC_END);
    buf->st_gid = mylong;
    rpc_get (sock, RPC_INT, &mylong, RPC_END);
    buf->st_size = mylong;

    if (!rpc_get (sock, RPC_INT, &mylong, RPC_END))
	return 0;
#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
    buf->st_blocks = mylong;
#endif
    buf->st_atime = mcfs_get_time (mc);
    buf->st_mtime = mcfs_get_time (mc);
    buf->st_ctime = mcfs_get_time (mc);
    return 1;
}

static int
mcfs_stat_cmd (int cmd, const char *path, struct stat *buf)
{
    char *remote_file;
    mcfs_connection *mc;
    int status, error;

    if ((remote_file = mcfs_get_path (&mc, path)) == 0)
	return -1;

    rpc_send (mc->sock, RPC_INT, cmd, RPC_STRING, remote_file, RPC_END);
    g_free (remote_file);
    if (!rpc_get (mc->sock, RPC_INT, &status, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, errno);

    if (mcfs_is_error (status, error))
	return -1;

    if (mcfs_get_stat_info (mc, buf))
	return 0;
    else
	return mcfs_set_error (-1, EIO);
}

static int
mcfs_stat (struct vfs_class *me, const char *path, struct stat *buf)
{
    (void) me;

    return mcfs_stat_cmd (MC_STAT, path, buf);
}

static int
mcfs_lstat (struct vfs_class *me, const char *path, struct stat *buf)
{
    int path_len = strlen (path);
    int entry_len = strlen (mcfs_readdir_data.dent.d_name);

    (void) me;

    /* Hack ... */
    if (strcmp (path + path_len - entry_len,
		mcfs_readdir_data.dent.d_name) == 0 && cached_lstat_info) {
	*buf = *cached_lstat_info;
	return 0;
    }
    return mcfs_stat_cmd (MC_LSTAT, path, buf);
}

static int
mcfs_fstat (void *data, struct stat *buf)
{
    mcfs_handle *info = (mcfs_handle *) data;
    int result, error;
    int handle, sock;

    sock = info->conn->sock;
    handle = info->handle;

    rpc_send (sock, RPC_INT, MC_FSTAT, RPC_INT, handle, RPC_END);
    if (!rpc_get (sock, RPC_INT, &result, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, EIO);

    if (mcfs_is_error (result, error))
	return -1;

    if (mcfs_get_stat_info (info->conn, buf))
	return 0;
    else
	return mcfs_set_error (-1, EIO);
}

static int
mcfs_chmod (struct vfs_class *me, const char *path, int mode)
{
    (void) me;

    return mcfs_rpc_path_int (MC_CHMOD, path, mode);
}

static int
mcfs_chown (struct vfs_class *me, const char *path, int owner, int group)
{
    (void) me;

    return mcfs_rpc_path_int_int (MC_CHOWN, path, owner, group);
}

static int
mcfs_utime (struct vfs_class *me, const char *path, struct utimbuf *times)
{
    mcfs_connection *mc;
    int status;
    char *file;

    (void) me;

    if (!(file = mcfs_get_path (&mc, path)))
	return -1;

    status = 0;
    if (mc->version >= 2) {
	char abuf[BUF_SMALL];
	char mbuf[BUF_SMALL];
	long atime, mtime;

	atime = (long) times->actime;
	mtime = (long) times->modtime;

	g_snprintf (abuf, sizeof (abuf), "%lx", atime);
	g_snprintf (mbuf, sizeof (mbuf), "%lx", mtime);

	rpc_send (mc->sock, RPC_INT, MC_UTIME,
		  RPC_STRING, file,
		  RPC_STRING, abuf, RPC_STRING, mbuf, RPC_END);
	status = mcfs_handle_simple_error (mc->sock, 0);

    }
    g_free (file);
    return (status);
}

static int
mcfs_readlink (struct vfs_class *me, const char *path, char *buf, size_t size)
{
    char *remote_file, *stat_str;
    int status, error;
    mcfs_connection *mc;
    size_t len;

    (void) me;

    if (!(remote_file = mcfs_get_path (&mc, path)))
	return -1;

    rpc_send (mc->sock, RPC_INT, MC_READLINK, RPC_STRING, remote_file,
	      RPC_END);
    g_free (remote_file);
    if (!rpc_get (mc->sock, RPC_INT, &status, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, EIO);

    if (mcfs_is_error (status, errno))
	return -1;

    if (!rpc_get (mc->sock, RPC_STRING, &stat_str, RPC_END))
	return mcfs_set_error (-1, EIO);

    len = strlen (stat_str);
    if (len < size)
       size = len;
    /* readlink() does not append a NUL character to buf */
    memcpy (buf, stat_str, size);
    g_free (stat_str);
    return size;
}

static int
mcfs_unlink (struct vfs_class *me, const char *path)
{
    (void) me;

    return mcfs_rpc_path (MC_UNLINK, path);
}

static int
mcfs_symlink (struct vfs_class *me, const char *n1, const char *n2)
{
    (void) me;

    return mcfs_rpc_two_paths (MC_SYMLINK, n1, n2);
}

static int
mcfs_rename (struct vfs_class *me, const char *a, const char *b)
{
    (void) me;

    return mcfs_rpc_two_paths (MC_RENAME, a, b);
}

static int
mcfs_chdir (struct vfs_class *me, const char *path)
{
    char *remote_dir;
    mcfs_connection *mc;
    int status, error;

    (void) me;

    if (!(remote_dir = mcfs_get_path (&mc, path)))
	return -1;

    rpc_send (mc->sock, RPC_INT, MC_CHDIR, RPC_STRING, remote_dir,
	      RPC_END);
    g_free (remote_dir);
    if (!rpc_get (mc->sock, RPC_INT, &status, RPC_INT, &error, RPC_END))
	return mcfs_set_error (-1, EIO);

    if (mcfs_is_error (status, error))
	return -1;
    return 0;
}

static off_t
mcfs_lseek (void *data, off_t offset, int whence)
{
    mcfs_handle *info = (mcfs_handle *) data;
    int handle, sock;

    sock = info->conn->sock;
    handle = info->handle;

    /* FIXME: off_t may be too long to fit */
    rpc_send (sock, RPC_INT, MC_LSEEK, RPC_INT, handle, RPC_INT,
	      (int) offset, RPC_INT, whence, RPC_END);

    return mcfs_handle_simple_error (sock, 1);
}

static int
mcfs_mknod (struct vfs_class *me, const char *path, int mode, int dev)
{
    (void) me;

    return mcfs_rpc_path_int_int (MC_MKNOD, path, mode, dev);
}

static int
mcfs_mkdir (struct vfs_class *me, const char *path, mode_t mode)
{
    (void) me;

    return mcfs_rpc_path_int (MC_MKDIR, path, mode);
}

static int
mcfs_rmdir (struct vfs_class *me, const char *path)
{
    (void) me;

    return mcfs_rpc_path (MC_RMDIR, path);
}

static int
mcfs_link (struct vfs_class *me, const char *p1, const char *p2)
{
    (void) me;

    return mcfs_rpc_two_paths (MC_LINK, p1, p2);
}

/* Gives up on a socket and reopens the connection, the child own the socket
 * now
 */
static void
mcfs_forget (const char *path)
{
    char *host, *user, *pass, *p;
    int port, i, vers;

    if (strncmp (path, "/#mc:", 5))
	return;

    path += 5;
    if (path[0] == '/' && path[1] == '/')
	path += 2;

    if ((p =
	 mcfs_get_host_and_username (path, &host, &user, &port,
				     &pass)) == 0) {
	g_free (host);
	g_free (user);
	if (pass)
	    wipe_password (pass);
	return;
    }
    for (i = 0; i < MCFS_MAX_CONNECTIONS; i++) {
	if ((strcmp (host, mcfs_connections[i].host) == 0) &&
	    (strcmp (user, mcfs_connections[i].user) == 0) &&
	    (port == mcfs_connections[i].port)) {

	    /* close socket: the child owns it now */
	    close (mcfs_connections[i].sock);

	    /* reopen the connection */
	    mcfs_connections[i].sock =
		mcfs_open_tcp_link (host, user, &port, pass, &vers);
	}
    }
    g_free (p);
    g_free (host);
    g_free (user);
    if (pass)
	wipe_password (pass);
}

static int
mcfs_setctl (struct vfs_class *me, const char *path, int ctlop, void *arg)
{
    (void) me;
    (void) arg;

    switch (ctlop) {
    case VFS_SETCTL_FORGET:
	mcfs_forget (path);
	return 0;
    }
    return 0;
}

void
init_mcfs (void)
{
    vfs_mcfs_ops.name = "mcfs";
    vfs_mcfs_ops.prefix = "mc:";
    vfs_mcfs_ops.fill_names = mcfs_fill_names;
    vfs_mcfs_ops.open = mcfs_open;
    vfs_mcfs_ops.close = mcfs_close;
    vfs_mcfs_ops.read = mcfs_read;
    vfs_mcfs_ops.write = mcfs_write;
    vfs_mcfs_ops.opendir = mcfs_opendir;
    vfs_mcfs_ops.readdir = mcfs_readdir;
    vfs_mcfs_ops.closedir = mcfs_closedir;
    vfs_mcfs_ops.stat = mcfs_stat;
    vfs_mcfs_ops.lstat = mcfs_lstat;
    vfs_mcfs_ops.fstat = mcfs_fstat;
    vfs_mcfs_ops.chmod = mcfs_chmod;
    vfs_mcfs_ops.chown = mcfs_chown;
    vfs_mcfs_ops.utime = mcfs_utime;
    vfs_mcfs_ops.readlink = mcfs_readlink;
    vfs_mcfs_ops.symlink = mcfs_symlink;
    vfs_mcfs_ops.link = mcfs_link;
    vfs_mcfs_ops.unlink = mcfs_unlink;
    vfs_mcfs_ops.rename = mcfs_rename;
    vfs_mcfs_ops.chdir = mcfs_chdir;
    vfs_mcfs_ops.ferrno = mcfs_errno;
    vfs_mcfs_ops.lseek = mcfs_lseek;
    vfs_mcfs_ops.mknod = mcfs_mknod;
    vfs_mcfs_ops.mkdir = mcfs_mkdir;
    vfs_mcfs_ops.rmdir = mcfs_rmdir;
    vfs_mcfs_ops.setctl = mcfs_setctl;
    vfs_register_class (&vfs_mcfs_ops);
}

static void
mcfs_free_bucket (int bucket)
{
    g_free (mcfs_connections[bucket].host);
    g_free (mcfs_connections[bucket].user);
    g_free (mcfs_connections[bucket].home);

    /* Set all the fields to zero */
    mcfs_connections[bucket].host =
	mcfs_connections[bucket].user = mcfs_connections[bucket].home = 0;
    mcfs_connections[bucket].sock = mcfs_connections[bucket].version = 0;
}

static int
mcfs_invalidate_socket (int sock)
{
    int i, j = -1;

    for (i = 0; i < MCFS_MAX_CONNECTIONS; i++)
	if (mcfs_connections[i].sock == sock) {
	    mcfs_free_bucket (i);
	    j = 0;
	}

    if (j == -1)
	return -1;		/* It was not our sock */
    /* Break from any possible loop */
    mc_chdir ("/");
    return 0;
}

void
tcp_invalidate_socket (int sock)
{
    mcfs_invalidate_socket (sock);
}
#else
void mcfs__unused(void)
{
/*
    CFLAGS="-ansi -pedantic -Wall -Wextra -Werror"
*/
}
#endif				/* WITH_MCFS */