From 40ab805df48b2f65d5028ba59063e2a36f19f452 Mon Sep 17 00:00:00 2001 From: Svante Signell Date: Wed, 30 Oct 2019 02:33:27 +0100 Subject: libnetfs: 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(netfs_S_file_record_lock): Don't set rendezvous to MACH_PORT_NULL. 2017-01-05 Svante Signell * Update copyright years and headers. * dir-lookup.c(netfs_S_dir_lookup): Call fshelp_rlock_tweak() with new last argument rendezvous = MACH_PORT_NULL. * file-lock.c(netfs_S_file_lock): Likewise. * file-record-lock.c(netfs_S_file_record_lock): Likewise. (netfs_S_file_record_lock): Add new argument mach_port_t rendezvous. 2016-05-23 Svante Signell * netfs.h (struct peropen): Change the type of rlock_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 (netfs_S_dir_lookup): Use fshelp_rlock_tweak. * file-lock-stat.c (netfs_S_file_lock_stat): Total rewrite around the new record locking functions. * file-lock.c (netfs_S_file_lock): Likewise. * file-record-lock.c (netfs_S_file_record_lock): Likewise. * make-node.c (netfs_make_node): Initialize userbox with fshelp_rlock_init. * make-peropen.c (netfs_make_peropen): Initialize lock_status using fshelp_rlock_po_init. (netfs_make_peropen): Add a comment that po->refcnt starts at zero. * relese-peropen.c (netfs_release_peropen): Release lock_status using fshelp_rlock_drop_peropen. 2001-04-11 Neal H Walfield * file-record-lock.c: New file. Implement netfs_S_file_record_lock. * Makefile (SRCS): Add file-record-lock.c --- libnetfs/file-lock.c | 48 ++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 40 insertions(+), 8 deletions(-) (limited to 'libnetfs/file-lock.c') diff --git a/libnetfs/file-lock.c b/libnetfs/file-lock.c index 0010d4be..7bb81d43 100644 --- a/libnetfs/file-lock.c +++ b/libnetfs/file-lock.c @@ -1,5 +1,5 @@ -/* - Copyright (C) 1995 Free Software Foundation, Inc. +/* + Copyright (C) 1995, 2015-2019 Free Software Foundation, Inc. Written by Michael I. Bushnell, p/BSG. This file is part of the GNU Hurd. @@ -15,22 +15,54 @@ 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. */ + along with the GNU Hurd. If not, see . */ #include "netfs.h" #include "fs_S.h" +#include +#include + error_t netfs_S_file_lock (struct protid *user, int flags) { error_t err; + struct flock64 lock; + struct node *node; + int openstat = user->po->openstat; + mach_port_t rendezvous = MACH_PORT_NULL; + if (!user) return EOPNOTSUPP; - pthread_mutex_lock (&user->po->np->lock); - err = fshelp_acquire_lock (&user->po->np->userlock, &user->po->lock_status, - &user->po->np->lock, flags); - pthread_mutex_unlock (&user->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 = user->po->np; + pthread_mutex_lock (&node->lock); + err = fshelp_rlock_tweak (&node->userlock, &node->lock, + &user->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