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nsmux.c
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/*---------------------------------------------------------------------------*/
/*nsmux.c*/
/*---------------------------------------------------------------------------*/
/*The filesystem proxy for namespace-based translator selection.*/
/*---------------------------------------------------------------------------*/
/*Based on the code of unionfs translator.*/
/*---------------------------------------------------------------------------*/
/*Copyright (C) 2001, 2002, 2005, 2008, 2009 Free Software Foundation,
Inc. Written by Sergiu Ivanov <unlimitedscolobb@gmail.com>.
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.*/
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
#define _GNU_SOURCE 1
/*---------------------------------------------------------------------------*/
#include "nsmux.h"
/*---------------------------------------------------------------------------*/
#include <error.h>
#include <argp.h>
#include <hurd/netfs.h>
#include <fcntl.h>
#include <hurd/paths.h>
#include <hurd/fsys.h>
/*---------------------------------------------------------------------------*/
#include "debug.h"
#include "options.h"
#include "ncache.h"
#include "magic.h"
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/*--------Global Variables---------------------------------------------------*/
/*The name of the server*/
char *netfs_server_name = "nsmux";
/*---------------------------------------------------------------------------*/
/*The version of the server*/
char *netfs_server_version = "0.0";
/*---------------------------------------------------------------------------*/
/*The maximal length of a chain of symbolic links*/
int netfs_maxsymlinks = 12;
/*---------------------------------------------------------------------------*/
/*A port to the underlying node*/
mach_port_t underlying_node;
/*---------------------------------------------------------------------------*/
/*Status information for the underlying node*/
io_statbuf_t underlying_node_stat;
/*---------------------------------------------------------------------------*/
/*Mapped time used for updating node information*/
volatile struct mapped_time_value *maptime;
/*---------------------------------------------------------------------------*/
/*The filesystem ID*/
pid_t fsid;
/*---------------------------------------------------------------------------*/
/*The file to print debug messages to*/
FILE *nsmux_dbg;
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/*--------Functions----------------------------------------------------------*/
/*Attempts to create a file named `name` in `dir` for `user` with mode `mode`*/
error_t
netfs_attempt_create_file
(struct iouser *user,
struct node *dir, char *name, mode_t mode, struct node **node)
{
LOG_MSG ("netfs_attempt_create_file");
/*Unlock `dir` and say that we can do nothing else here */
mutex_unlock (&dir->lock);
return EOPNOTSUPP;
} /*netfs_attempt_create_file */
/*---------------------------------------------------------------------------*/
/*Return an error if the process of opening a file should not be
allowed to complete because of insufficient permissions*/
error_t
netfs_check_open_permissions
(struct iouser * user, struct node * np, int flags, int newnode)
{
LOG_MSG ("netfs_check_open_permissions: '%s'", np->nn->lnode->name);
/*Cheks user's permissions and return the result */
return check_open_permissions (user, &np->nn_stat, flags);
} /*netfs_check_open_permissions */
/*---------------------------------------------------------------------------*/
/*Attempts an utimes call for the user `cred` on node `node`*/
error_t
netfs_attempt_utimes
(struct iouser * cred,
struct node * node, struct timespec * atime, struct timespec * mtime)
{
LOG_MSG ("netfs_attempt_utimes");
error_t err = 0;
/*See what information is to be updated */
int flags = TOUCH_CTIME;
/*Check if the user is indeed the owner of the node */
err = fshelp_isowner (&node->nn_stat, cred);
/*If the user is allowed to do utimes */
if (!err)
{
/*If atime is to be updated */
if (atime)
/*update the atime */
node->nn_stat.st_atim = *atime;
else
/*the current time will be set as the atime */
flags |= TOUCH_ATIME;
/*If mtime is to be updated */
if (mtime)
/*update the mtime */
node->nn_stat.st_mtim = *mtime;
else
/*the current time will be set as mtime */
flags |= TOUCH_MTIME;
/*touch the file */
fshelp_touch (&node->nn_stat, flags, maptime);
}
/*Return the result of operations */
return err;
} /*netfs_attempt_utimes */
/*---------------------------------------------------------------------------*/
/*Returns the valid access types for file `node` and user `cred`*/
error_t
netfs_report_access (struct iouser * cred, struct node * np, int *types)
{
LOG_MSG ("netfs_report_access");
/*No access at first */
*types = 0;
/*Check the access and set the required bits */
if (fshelp_access (&np->nn_stat, S_IREAD, cred) == 0)
*types |= O_READ;
if (fshelp_access (&np->nn_stat, S_IWRITE, cred) == 0)
*types |= O_WRITE;
if (fshelp_access (&np->nn_stat, S_IEXEC, cred) == 0)
*types |= O_EXEC;
/*Everything OK */
return 0;
} /*netfs_report_access */
/*---------------------------------------------------------------------------*/
/*Validates the stat data for the node*/
error_t netfs_validate_stat (struct node * np, struct iouser * cred)
{
LOG_MSG ("netfs_validate_stat: '%s'",
((np && np->nn->lnode) ? np->nn->lnode->name : ""));
error_t err = 0;
/*If we are not at the root */
if (np != netfs_root_node)
{
/*If the node is not surely up-to-date */
if (!(np->nn->flags & FLAG_NODE_ULFS_UPTODATE))
{
/*update it */
err = node_update (np);
}
/*If no errors have yet occurred */
if (!err)
{
/*If the port to the file corresponding to `np` is valid */
if (np->nn->port != MACH_PORT_NULL)
{
/*We have a directory here (normally, only they maintain an open port).
Generally, our only concern is to maintain an open port in this case */
/*attempt to stat this file */
err = io_stat (np->nn->port, &np->nn_stat);
if (S_ISDIR (np->nn_stat.st_mode))
LOG_MSG ("\tIs a directory");
/*If stat information has been successfully obtained for the file */
if (!err)
/*duplicate the st_mode field of stat structure */
np->nn_translated = np->nn_stat.st_mode;
}
else
{
/*We, most probably, have something which is not a
directory. Therefore we will open the port and close
it after the stat, so that additional resources are
not consumed. */
/*the parent node of the current node */
node_t *dnp;
/*obtain the parent node of the the current node */
err = ncache_node_lookup (np->nn->lnode->dir, &dnp);
/*the lookup should never fail here */
assert (!err);
/*open a port to the file we are interested in */
mach_port_t p = file_name_lookup_under
(dnp->nn->port, np->nn->lnode->name, 0, 0);
/*put `dnp` back, since we don't need it any more */
netfs_nput (dnp);
if (!p)
return EBADF;
/*try to stat the node */
err = io_stat (p, &np->nn_stat);
/*deallocate the port */
PORT_DEALLOC (p);
}
}
}
/*If we are at the root */
else
/*put the size of the node into the stat structure belonging to `np` */
node_get_size (np, (OFFSET_T *) & np->nn_stat.st_size);
/*Return the result of operations */
return err;
} /*netfs_validate_stat */
/*---------------------------------------------------------------------------*/
/*Syncs `node` completely to disk*/
error_t
netfs_attempt_sync (struct iouser * cred, struct node * node, int wait)
{
LOG_MSG ("netfs_attempt_sync");
/*Operation is not supported */
return EOPNOTSUPP;
} /*netfs_attempt_sync */
/*---------------------------------------------------------------------------*/
/*Fetches a directory*/
error_t
netfs_get_dirents
(struct iouser * cred,
struct node * dir,
int first_entry,
int num_entries,
char **data,
mach_msg_type_number_t * data_len,
vm_size_t max_data_len, int *data_entries)
{
LOG_MSG ("netfs_get_dirents: '%s'", dir->nn->lnode->name);
error_t err;
/*Two pointers required for processing the list of dirents */
node_dirent_t *dirent_start, *dirent_current;
/*The pointer to the beginning of the list of dirents */
node_dirent_t *dirent_list = NULL;
/*The size of the current dirent */
size_t size = 0;
/*The number of dirents added */
int count = 0;
/*The dereferenced value of parameter `data` */
char *data_p;
/*Takes into account the size of the given dirent */
int bump_size (const char *name)
{
/*If the required number of entries has not been listed yet */
if ((num_entries == -1) || (count < num_entries))
{
/*take the current size and take into account the length of the name */
size_t new_size = size + DIRENT_LEN (strlen (name));
/*If there is a limit for the received size and it has been exceeded */
if ((max_data_len > 0) && (new_size > max_data_len))
/*a new dirent cannot be added */
return 0;
/*memorize the new size */
size = new_size;
/*increase the number of dirents added */
++count;
/*everything is OK */
return 1;
}
else
{
/*dirents cannot be added */
return 0;
}
} /*bump_size */
/*Adds a dirent to the list of dirents */
int add_dirent (const char *name, ino_t ino, int type)
{
/*If the required number of dirents has not been listed yet */
if ((num_entries == -1) || (count < num_entries))
{
/*create a new dirent */
struct dirent hdr;
/*obtain the length of the name */
size_t name_len = strlen (name);
/*compute the full size of the dirent */
size_t sz = DIRENT_LEN (name_len);
/*If there is no room for this dirent */
if (sz > size)
/*stop */
return 0;
else
/*take into account the fact that a new dirent has just been added */
size -= sz;
/*setup the dirent */
hdr.d_ino = ino;
hdr.d_reclen = sz;
hdr.d_type = type;
hdr.d_namlen = name_len;
/*The following two lines of code reflect the old layout of
dirents in the memory. Now libnetfs expects the layout
identical to the layout provided by dir_readdir
see dir_entries_get) */
/*copy the header of the dirent into the final block of dirents */
memcpy (data_p, &hdr, DIRENT_NAME_OFFS);
/*copy the name of the dirent into the block of dirents */
strcpy (data_p + DIRENT_NAME_OFFS, name);
/*This line is commented for the same reason as the two specifically
commented lines above. */
/*move the current pointer in the block of dirents */
data_p += sz;
/*count the new dirent */
++count;
/*everything was OK, so say it */
return 1;
}
else
/*no [new] dirents allowed */
return 0;
} /*add_dirent */
/*List the dirents for node `dir` */
err = node_entries_get (dir, &dirent_list);
/*If listing was successful */
if (!err)
{
/*find the entry whose number is `first_entry` */
for
(dirent_start = dirent_list, count = 2;
dirent_start && (count < first_entry);
dirent_start = dirent_start->next, ++count);
/*reset number of dirents added so far */
count = 0;
/*make space for entries '.' and '..', if required */
if (first_entry == 0)
bump_size (".");
if (first_entry <= 1)
bump_size ("..");
/*Go through all dirents */
for
(dirent_current = dirent_start;
dirent_current; dirent_current = dirent_current->next)
/*If another dirent cannot be added succesfully */
if (bump_size (dirent_current->dirent->d_name) == 0)
/*stop here */
break;
/*allocate the required space for dirents */
*data = mmap (0, size, PROT_READ | PROT_WRITE, MAP_ANON, 0, 0);
/*check if any error occurred */
err = ((void *) *data == MAP_FAILED) ? (errno) : (0);
}
/*If no errors have occurred so far */
if (!err)
{
/*obtain the pointer to the beginning of the block of dirents */
data_p = *data;
/*fill the parameters with useful values */
*data_len = size;
*data_entries = count;
/*reset the number of dirents added */
count = 0;
/*add entries '.' and '..', if required */
if (first_entry == 0)
add_dirent (".", 2, DT_DIR);
if (first_entry <= 1)
add_dirent ("..", 2, DT_DIR);
/*Follow the list of dirents beginning with dirents_start */
for
(dirent_current = dirent_start; dirent_current;
dirent_current = dirent_current->next)
/*If the addition of the current dirent fails */
if (add_dirent
(dirent_current->dirent->d_name, dirent_current->dirent->d_fileno,
dirent_current->dirent->d_type) == 0)
/*stop adding dirents */
break;
}
/*If the list of dirents has been allocated, free it */
if (dirent_list)
node_entries_free (dirent_list);
/*The directory has been read right now, modify the access time */
fshelp_touch (&dir->nn_stat, TOUCH_ATIME, maptime);
/*Return the result of listing the dirents */
return err;
} /*netfs_get_dirents */
/*---------------------------------------------------------------------------*/
/*Looks up `name` under `dir` for `user`*/
error_t
netfs_attempt_lookup
(struct iouser * user, struct node * dir, char *name, struct node ** node)
{
LOG_MSG ("netfs_attempt_lookup");
/*We should never get here. In any case, we do not want to do this type
of lookup, netfs_attempt_lookup_improved is what we want */
return EOPNOTSUPP;
} /*netfs_attempt_lookup */
/*---------------------------------------------------------------------------*/
/*Performs an advanced lookup of file `name` under `dir`. If the
lookup of the last component of the path is requested (`lastcomp` is
1), it is not a directory and the creation of proxy (shadow) node is
not required (`proxy` is 1), the function will simply open the
required file and return the port in `file`. In other cases it will
create a proxy node and return it in `node`.*/
error_t
netfs_attempt_lookup_improved
(struct iouser * user, struct node * dir, char *name, int flags,
int lastcomp, node_t ** node, file_t * file, int proxy)
{
LOG_MSG ("netfs_attempt_lookup_improved: '%s'", name);
error_t err = 0;
/*If we are asked to fetch the current directory */
if (strcmp (name, ".") == 0)
{
/*validate the stat information for `dir` */
err = netfs_validate_stat (dir, user);
if (err)
{
mutex_unlock (&dir->lock);
return err;
}
/*If `dir` is not a directory, actually */
if (!S_ISDIR (dir->nn_stat.st_mode))
{
/*unlock the directory and stop right here */
mutex_unlock (&dir->lock);
return ENOTDIR;
}
/*add a reference to `dir` and put it into `node` */
netfs_nref (dir);
*node = dir;
/*everything is OK */
return 0;
}
/*If we are asked to fetch the parent directory */
else if (strcmp (name, "..") == 0)
{
/*validate the stat information for `dir` */
err = netfs_validate_stat (dir, user);
if (err)
{
mutex_unlock (&dir->lock);
return err;
}
/*If `dir` is not a directory, actually */
if (!S_ISDIR (dir->nn_stat.st_mode))
{
/*unlock the directory and stop right here */
mutex_unlock (&dir->lock);
return ENOTDIR;
}
/*If the supplied node is not root */
if (dir->nn->lnode->dir)
{
/*The node corresponding to the parent directory must exist here */
assert (dir->nn->lnode->dir->node);
/*put the parent node of `dir` into the result */
err = ncache_node_lookup (dir->nn->lnode->dir, node);
}
/*The supplied node is root */
else
{
/*this node is not included into our filesystem */
err = ENOENT;
*node = NULL;
}
/*unlock the directory */
mutex_unlock (&dir->lock);
/*stop here */
return err;
}
/*The port to the requested file */
mach_port_t p;
/*The lnode corresponding to the entry we are supposed to fetch */
lnode_t *lnode;
/*Is the looked up file a directory */
int isdir;
/*Finalizes the execution of this function */
void finalize (void)
{
/*If some errors have occurred */
if (err)
{
/*the user should receive nothing */
*node = NULL;
/*If there is some port, free it */
if (p != MACH_PORT_NULL)
PORT_DEALLOC (p);
}
/*If there is a node to return */
if (*node)
{
/*unlock the node */
mutex_unlock (&(*node)->lock);
/*add the node to the cache */
ncache_node_add (*node);
}
/*Unlock the mutexes in `dir` */
mutex_unlock (&dir->nn->lnode->lock);
mutex_unlock (&dir->lock);
} /*finalize */
/*Performs a usual lookup */
error_t lookup (char *name, /*lookup this */
int flags, /*lookup `name` in the this way */
int proxy /*should a proxy node be created */
)
{
/*Try to lookup the given file in the underlying directory */
p = file_name_lookup_under (dir->nn->port, name, 0, 0);
/*If the lookup failed */
if (p == MACH_PORT_NULL)
/*no such entry */
return ENOENT;
/*Obtain the stat information about the file */
io_statbuf_t stat;
err = io_stat (p, &stat);
/*Deallocate the obtained port */
PORT_DEALLOC (p);
/*If this file is not a directory */
if (err || !S_ISDIR (stat.st_mode))
{
/*remember we do not have a directory */
isdir = 0;
if (!proxy)
{
/*We don't need to do lookups here if a proxy shadow node
is required. The lookup will be done by the translator
starting procedure. Just check whether the file
exists.*/
p = file_name_lookup_under (dir->nn->port, name, flags, 0);
if (p == MACH_PORT_NULL)
return EBADF;
/*If a proxy node is not required */
if (!proxy)
/*stop here, we want only the port to the file */
return 0;
}
else
p = MACH_PORT_NULL;
}
else
{
if (!lastcomp || !proxy)
{
p = file_name_lookup_under
(dir->nn->port, name, flags | O_READ | O_DIRECTORY, 0);
if (p == MACH_PORT_NULL)
return EBADF; /*not enough rights? */
}
else
/*If we are at the last component of the path and need to
open a directory, do not do the lookup; the translator
starting procedure will do that.*/
p = MACH_PORT_NULL;
/*we have a directory here */
isdir = 1;
}
/*Try to find an lnode called `name` under the lnode corresponding
to `dir` */
err = lnode_get (dir->nn->lnode, name, &lnode);
/*If such an entry does not exist */
if (err == ENOENT)
{
/*create a new lnode with the supplied name */
err = lnode_create (name, &lnode);
if (err)
{
finalize ();
return err;
}
/*install the new lnode into the directory */
lnode_install (dir->nn->lnode, lnode);
}
/*If we are to create a proxy node */
if (proxy)
/*create a proxy node from the given lnode */
err = node_create_proxy (lnode, node);
/*If we don't need proxy nodes in this lookup */
else
{
/*obtain the node corresponding to this lnode */
err = ncache_node_lookup (lnode, node);
/*remove an extra reference from the lnode */
lnode_ref_remove (lnode);
}
/*If either the lookup in the cache or the creation of a proxy failed */
if (err)
{
/*stop */
mutex_unlock (&lnode->lock);
finalize ();
return err;
}
/*Store the port in the node */
(*node)->nn->port = p;
/*Fill in the flag about the node being a directory */
if (isdir)
lnode->flags |= FLAG_LNODE_DIR;
else
lnode->flags &= ~FLAG_LNODE_DIR;
/*Construct the full path to the node */
err = lnode_path_construct (lnode, NULL);
if (err)
{
mutex_unlock (&lnode->lock);
finalize ();
return err;
}
/*Unlock the lnode */
mutex_unlock (&lnode->lock);
/*Now the node is up-to-date */
(*node)->nn->flags = FLAG_NODE_ULFS_UPTODATE;
/*Everything OK here */
return 0;
} /*lookup */
/*Simply lookup the provided name, without creating the proxy, if not
necessary (i.e. when the file is not a directory) */
err = lookup (name, flags, proxy);
if (err)
{
finalize ();
return err;
}
/*if we have looked up a regular file, store the port to it in *`file` */
if (!isdir)
*file = p;
/*Everything OK here */
finalize ();
return err;
} /*netfs_attempt_lookup_improved */
/*---------------------------------------------------------------------------*/
/*Responds to the RPC dir_lookup*/
error_t
netfs_S_dir_lookup
(struct protid * diruser,
char *filename,
int flags,
mode_t mode,
retry_type * do_retry,
char *retry_name,
mach_port_t * retry_port, mach_msg_type_number_t * retry_port_type)
{
LOG_MSG ("netfs_S_dir_lookup: '%s'", filename);
int create; /* true if O_CREAT flag set */
int excl; /* true if O_EXCL flag set */
int mustbedir = 0; /* true if the result must be S_IFDIR */
int lastcomp = 0; /* true if we are at the last component */
int newnode = 0; /* true if this node is newly created */
int nsymlinks = 0;
struct node *dnp, *np;
char *nextname;
error_t error;
struct protid *newpi;
struct iouser *user;
/*The old node (required in setting up translator stacks) */
struct node * old_np;
/*The port to the file */
file_t file = MACH_PORT_NULL;
/*The port to the same file with restricted rights */
file_t file_restricted = MACH_PORT_NULL;
/*The stat information about the node pointed at by `file` (for the case
when not proxy nodes are to be created) */
io_statbuf_t stat;
/*The position of the magic separator in the filename */
char * sep;
/*The position of the next magic separator in the filename */
char * nextsep;
/*The name of the translator to set in this retry */
char * trans = NULL;
/*The length of the name of the translator to set in this retry */
int trans_len = 0;
if (!diruser)
return EOPNOTSUPP;
create = (flags & O_CREAT);
excl = (flags & O_EXCL);
/* Skip leading slashes */
while (*filename == '/')
filename++;
*retry_port_type = MACH_MSG_TYPE_MAKE_SEND;
*do_retry = FS_RETRY_NORMAL;
*retry_name = '\0';
if (*filename == '\0')
{
/* Set things up in the state expected by the code from gotit: on. */
dnp = 0;
np = diruser->po->np;
mutex_lock (&np->lock);
netfs_nref (np);
goto gotit;
}
dnp = diruser->po->np;
mutex_lock (&dnp->lock);
netfs_nref (dnp); /* acquire a reference for later netfs_nput */
do
{
assert (!lastcomp);
/* Find the name of the next pathname component */
nextname = index (filename, '/');
if (nextname)
{
*nextname++ = '\0';
while (*nextname == '/')
nextname++;
if (*nextname == '\0')
{
/* These are the rules for filenames ending in /. */
nextname = 0;
lastcomp = 1;
mustbedir = 1;
create = 0;
}
else
lastcomp = 0;
}
else
lastcomp = 1;
np = 0;
retry_lookup:
if ((dnp == netfs_root_node || dnp == diruser->po->shadow_root)
&& filename[0] == '.' && filename[1] == '.' && filename[2] == '\0')
if (dnp == diruser->po->shadow_root)
/* We're at the root of a shadow tree. */
{
*do_retry = FS_RETRY_REAUTH;
*retry_port = diruser->po->shadow_root_parent;
*retry_port_type = MACH_MSG_TYPE_COPY_SEND;
if (!lastcomp)
strcpy (retry_name, nextname);
error = 0;
mutex_unlock (&dnp->lock);
goto out;
}
else if (diruser->po->root_parent != MACH_PORT_NULL)
/* We're at a real translator root; even if DIRUSER->po has a
shadow root, we can get here if its in a directory that was
renamed out from under it... */
{
*do_retry = FS_RETRY_REAUTH;
*retry_port = diruser->po->root_parent;
*retry_port_type = MACH_MSG_TYPE_COPY_SEND;
if (!lastcomp)
strcpy (retry_name, nextname);
error = 0;
mutex_unlock (&dnp->lock);
goto out;
}
else
/* We are global root */
{
error = 0;
np = dnp;
netfs_nref (np);
}
else
{
/* Attempt a lookup on the next pathname component. */
/*error = netfs_attempt_lookup (diruser->user, dnp, filename, &np);*/
/*try to find the magic separator in the filename */
sep = magic_find_sep (filename);
if (sep)
{
sep[0] = sep[1] = 0;
sep += 2;
/*We have to create a shadow node and set a translator
on it. */
if (sep == filename + 2)
{
/*this is a retry, so no need to do lookups */
error = 0;
np = dnp;
netfs_nref (np);
mutex_unlock (&np->lock);
/*`np` is a proxy node of the lower translator. We
have to create a shadow node explicitly. */
error = node_get_send_port (diruser, np, flags, &file);
if (error)
goto out;
old_np = np;
error = node_create_from_port(file, &np);
if (error)
goto out;
/*connect the nodes into a chain. */
np->nn->below = old_np;
/*`np` is supposed to be unlocked by the following
code. */
mutex_unlock (&np->lock);
}
else
/*lookup the file in the real filesystem */
error = netfs_attempt_lookup_improved
(diruser->user, dnp, filename, flags,
lastcomp, &np, &file, 1);
if (!error && !excl)
{
/*We've just created a shadow node. */
np->nn->type = NODE_TYPE_SHADOW;
/*If there is at least one more separator in the
filename, we will have to do a retry */
nextsep = magic_find_sep(sep);
if (nextsep)
{
trans_len = nextsep - sep;
trans = malloc (trans_len + 1);
if (!trans)
goto out;
strncpy(trans, sep, trans_len);
trans[trans_len] = 0;
/*set the required translator on the node */
error = node_set_translator
(diruser, np, trans, flags, filename, &file);
if (error)
goto out;
free (trans);
/*prepare the information for the retry */
strcpy (retry_name, nextsep);
if (nextname)
{
strcat (retry_name, "/");
strcat (retry_name, nextname);
}
/*create a proxy node for the port to the root
of translator */
netfs_nput (np);
old_np = np;
error = node_create_from_port (file, &np);
if(error)
goto out;
/*connect the nodes in a chain. */
np->nn->below = old_np;
/*create a port to the proxy node */
/*we don't check the permissions here, because
this check has been performed in the lookup of
the real filename at the beginning of the
process of setting up the dynamic translator
stack */
error = node_get_port (diruser, np, flags, retry_port);
if (np)
netfs_nput (np);
if (dnp)
netfs_nrele (dnp);
/*ask the client to retry */
return 0;
}