From dd7447b87c6d6d1afaf25553b0f911853dcc6683 Mon Sep 17 00:00:00 2001 From: Neal H Walfield Date: Tue, 29 Oct 2019 23:56:23 +0100 Subject: libdiskfs: Support for file record locking 2019-03-04 Svante Signell * file-lock.c: Make flock work regardless of the mode in which the file was opened. 2019-02-12 Svante Signell * file-lock.c: Comment out "Make flock work without R or W mode" 2019-02-01 Svante Signell * Update copyright years. * file-record-lock.c(diskfs_S_file_record_lock): Don't set rendezvous to MACH_PORT_NULL. 2018-12-07 Svante Signell * Update copyright years. * dir-lookup.c(diskfs_S_dir_lookup): Call fshelp_rlock_tweak() with new last argument rendezvous = MACH_PORT_NULL. * file-lock.c(diskfs_S_file_lock): Likewise. * file-record-lock.c(diskfs_S_file_record_lock): Likewise. (diskfs_S_file_record_lock): Add new argument mach_port_t rendezvous. 2017-01-05 Svante Signell * Update copyright years and headers. 2016-05-23 Svante Signell * file-lock-stat.c: Port from cthreads to libpthread. * file-lock.c: Likewise. * file-record-lock: Likewise. 2001-04-11 Neal H Walfield * Makefile (FSSRCS): Add file-record-lock.c. * diskfs.h (struct peropen): Change the type of lock_status from an int to a struct rlock_peropen. (struct node): Change the type of userbox from a struct lock_box to a struct rlock_box. * dir-lookup.c (diskfs_S_dir_lookup): Use fshelp_rlock_tweak as fshelp_acquire_lock is now depreciated. * file-lock-stat.c (diskfs_S_file_lock_stat): Total rewrite around the new record locking functions. * file-lock.c (diskfs_S_file_lock): Total rewrite around the new record locking functions. * file-record-lock.c: New file. Implement diskfs_S_file_record_lock. * node-make.c (diskfs_make_node): Initialize userbox with fshelp_rlock_init. * peropen-make.c (diskfs_make_peropen): Initialize lock_status using fshelp_rlock_po_init. * peropen-rele.c (diskfs_release_peropen): Release lock_status using fshelp_rlock_drop_peropen. --- libdiskfs/file-lock.c | 68 ++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 48 insertions(+), 20 deletions(-) (limited to 'libdiskfs/file-lock.c') diff --git a/libdiskfs/file-lock.c b/libdiskfs/file-lock.c index ab536e86..b95c3f0c 100644 --- a/libdiskfs/file-lock.c +++ b/libdiskfs/file-lock.c @@ -1,36 +1,64 @@ -/* - Copyright (C) 1993, 1994 Free Software Foundation +/* Copyright (C) 1993-1994, 2001, 2014-2019 Free Software Foundation, Inc. - This file is part of the GNU Hurd. + Written by Neal H Walfield - 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. + 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. - 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. + 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; see the file COPYING. If not, write to - the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ - -/* Written by Michael I. Bushnell. */ + along with the GNU Hurd. If not, see . */ #include "priv.h" #include "fs_S.h" +#include +#include + kern_return_t diskfs_S_file_lock (struct protid *cred, int flags) { error_t err; - if (!cred) + struct flock64 lock; + struct node *node; + int openstat = cred->po->openstat; + mach_port_t rendezvous = MACH_PORT_NULL; + + if (! cred) return EOPNOTSUPP; - pthread_mutex_lock (&cred->po->np->lock); - err = fshelp_acquire_lock (&cred->po->np->userlock, &cred->po->lock_status, - &cred->po->np->lock, flags); - pthread_mutex_unlock (&cred->po->np->lock); + + 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; } -- cgit v1.2.3