libnetfs: Support for file record locking

2019-03-04  Svante Signell <svante.signell@gmail.com>

	* file-lock.c: Make flock work regardless of the
          mode in which the file was opened.

2019-02-12  Svante Signell <svante.signell@gmail.com>

	* file-lock.c: Comment out "Make flock work without R or W mode"

2019-02-01  Svante Signell <svante.signell@gmail.com>

       * 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 <svante.signell@gmail.com>

	* 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 <svante.signell@gmail.com>

	* 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  <neal@cs.uml.edu>

	* file-record-lock.c: New file.  Implement
	netfs_S_file_record_lock.
	* Makefile (SRCS): Add file-record-lock.c

1 files changed, 44 insertions, 0 deletions

diff --git a/libnetfs/file-record-lock.c b/libnetfs/file-record-lock.c
new file mode 100644
index 00000000..049fc139
--- /dev/null
+++ b/libnetfs/file-record-lock.c
@@ -0,0 +1,44 @@
+/* Copyright (C) 2001, 2014-2019 Free Software Foundation, Inc.
+
+   Written by Neal H Walfield <neal@cs.uml.edu>
+
+   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 the GNU Hurd.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "netfs.h"
+
+#include <hurd/fshelp.h>
+
+error_t
+netfs_S_file_record_lock (struct protid *cred,
+			  int cmd,
+			  struct flock64 *lock,
+			  mach_port_t rendezvous)
+{
+  struct node *node;
+  error_t err;
+
+  if (! cred)
+    return EOPNOTSUPP;
+
+  node = cred->po->np;
+  pthread_mutex_lock (&node->lock);
+  err = fshelp_rlock_tweak (&node->userlock, &node->lock,
+			    &cred->po->lock_status, cred->po->openstat,
+			    node->nn_stat.st_size, cred->po->filepointer,
+			    cmd, lock, rendezvous);
+  pthread_mutex_unlock (&node->lock);
+  return err;
+}