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/* Copyright (C) 1993-1994, 2001, 2014-2019 Free Software Foundation, Inc.
Written by Neal H Walfield <neal@cs.uml.edu>
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, 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 the GNU Hurd. If not, see <http://www.gnu.org/licenses/>. */
#include "priv.h"
#include "fs_S.h"
#include <fcntl.h>
#include <sys/file.h>
kern_return_t
diskfs_S_file_lock (struct protid *cred, int flags)
{
error_t err;
struct flock64 lock;
struct node *node;
int openstat = cred->po->openstat;
mach_port_t rendezvous = MACH_PORT_NULL;
if (! cred)
return EOPNOTSUPP;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0;
if (flags & LOCK_UN)
lock.l_type = F_UNLCK;
else if (flags & LOCK_SH)
lock.l_type = F_RDLCK;
else if (flags & LOCK_EX)
lock.l_type = F_WRLCK;
else
return EINVAL;
/*
XXX: Fix for flock(2) calling fcntl(2)
From flock(2): A shared or exclusive lock can be placed on a file
regardless of the mode in which the file was opened.
*/
if (openstat & (O_RDONLY|O_WRONLY|O_EXEC)) openstat |= O_RDONLY|O_WRONLY;
node = cred->po->np;
pthread_mutex_lock (&node->lock);
err = fshelp_rlock_tweak (&node->userlock, &node->lock,
&cred->po->lock_status, openstat,
0, 0, flags & LOCK_NB ? F_SETLK64 : F_SETLKW64,
&lock, rendezvous);
pthread_mutex_unlock (&node->lock);
return err;
}
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