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/* Creating a channel hub from a file name.
Copyright (C) 1996, 1997, 1998, 2001, 2002, 2007
Free Software Foundation, Inc.
Written by Miles Bader <miles@gnu.org>
Reworked for libchannel by Carl Fredrik Hammar <hammy.lite@gmail.com>
This file is part of the GNU Hurd.
The GNU Hurd 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, or (at
your option) any later version.
The GNU Hurd 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, USA. */
#include <fcntl.h>
#include <hurd.h>
#include "channel.h"
/* Open the file NAME and return a new hub in HUB, which is either a copy
of the file's underlying hub or a hub using it through file io, unless
CHANNEL_NO_FILEIO flag is given. The class of HUB is found in CLASSES
or CHANNEL_STD_CLASSES, if CLASSES is null. FLAGS is set with
channel_set_hub_flags. Keeps the SOURCE reference, which may be closed
using channel_close_hub_source. */
error_t
channel_create_query_hub (const char *name, int flags,
const struct channel_class *const *classes,
struct channel_hub **hub)
{
error_t err;
file_t node = file_name_lookup (name, O_READ, 0);
if (node == MACH_PORT_NULL)
{
mach_port_deallocate (mach_task_self (), node);
err = errno;
}
else
err = channel_fetch_hub (node, flags, classes, hub);
if (! err)
return 0;
if (flags & CHANNEL_NO_FILEIO)
return err;
/* Try making a hub that does file io to NODE. */
return channel_create_file_hub (name, flags, classes, hub);
}
const struct channel_class
channel_query_class = { name: "query", create_hub: channel_create_query_hub };
CHANNEL_STD_CLASS (query);
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