c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync/* $Id$ */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync/** @file
5b281ba489ca18f0380d7efc7a5108b606cce449vboxsync * IPRT - File Locking, POSIX.
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync/*
cae3b8810c39392e70dfb12b951431018a80fcbavboxsync * Copyright (C) 2006-2011 Oracle Corporation
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync *
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync * This file is part of VirtualBox Open Source Edition (OSE), as
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync * available from http://www.virtualbox.org. This file is free software;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync * you can redistribute it and/or modify it under the terms of the GNU
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * General Public License (GPL) as published by the Free Software
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * Foundation, in version 2 as it comes in the "COPYING" file of the
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync *
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * The contents of this file may alternatively be used under the terms
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * of the Common Development and Distribution License Version 1.0
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * VirtualBox OSE distribution, in which case the provisions of the
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * CDDL are applicable instead of those of the GPL.
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync *
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * You may elect to license modified versions of this file under the
a16eb14ad7a4b5ef91ddc22d3e8e92d930f736fcvboxsync * terms and conditions of either the GPL or the CDDL or both.
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync/*******************************************************************************
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync* Header Files *
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync*******************************************************************************/
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#define LOG_GROUP RTLOGGROUP_FILE
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <errno.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <sys/types.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <sys/ioctl.h>
611992ec6994e6050e4970a973d2f549f823a3eavboxsync#include <sys/fcntl.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <fcntl.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <unistd.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <sys/time.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <iprt/file.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <iprt/assert.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <iprt/string.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <iprt/err.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include <iprt/log.h>
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include "internal/file.h"
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync#include "internal/fs.h"
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
cae3b8810c39392e70dfb12b951431018a80fcbavboxsyncRTR3DECL(int) RTFileLock(RTFILE hFile, unsigned fLock, int64_t offLock, uint64_t cbLock)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync{
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync Assert(offLock >= 0);
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync /* Check arguments. */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync if (fLock & ~RTFILE_LOCK_MASK)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync {
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync AssertMsgFailed(("Invalid fLock=%08X\n", fLock));
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VERR_INVALID_PARAMETER;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync }
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync /*
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync * Validate offset.
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync if ( sizeof(off_t) < sizeof(cbLock)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync && ( (offLock >> 32) != 0
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync || (cbLock >> 32) != 0
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync || ((offLock + cbLock) >> 32) != 0))
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync {
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync AssertMsgFailed(("64-bit file i/o not supported! offLock=%lld cbLock=%lld\n", offLock, cbLock));
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VERR_NOT_SUPPORTED;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync }
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync /* Prepare flock structure. */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync struct flock fl;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync Assert(RTFILE_LOCK_WRITE);
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_type = (fLock & RTFILE_LOCK_WRITE) ? F_WRLCK : F_RDLCK;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_whence = SEEK_SET;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_start = (off_t)offLock;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_len = (off_t)cbLock;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_pid = 0;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync Assert(RTFILE_LOCK_WAIT);
cae3b8810c39392e70dfb12b951431018a80fcbavboxsync if (fcntl(RTFileToNative(hFile), (fLock & RTFILE_LOCK_WAIT) ? F_SETLKW : F_SETLK, &fl) >= 0)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VINF_SUCCESS;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync int iErr = errno;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync if (iErr == ENOTSUP)
611992ec6994e6050e4970a973d2f549f823a3eavboxsync {
611992ec6994e6050e4970a973d2f549f823a3eavboxsync /*
611992ec6994e6050e4970a973d2f549f823a3eavboxsync * This is really bad hack for getting VDIs to work somewhat
611992ec6994e6050e4970a973d2f549f823a3eavboxsync * safely on SMB mounts.
611992ec6994e6050e4970a973d2f549f823a3eavboxsync */
611992ec6994e6050e4970a973d2f549f823a3eavboxsync /** @todo we need to keep track of these locks really. Anyone requiring to lock more
611992ec6994e6050e4970a973d2f549f823a3eavboxsync * than one part of a file will have to fix this. */
611992ec6994e6050e4970a973d2f549f823a3eavboxsync unsigned f = 0;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync Assert(RTFILE_LOCK_WAIT);
611992ec6994e6050e4970a973d2f549f823a3eavboxsync if (fLock & RTFILE_LOCK_WAIT)
611992ec6994e6050e4970a973d2f549f823a3eavboxsync f |= LOCK_NB;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync if (fLock & RTFILE_LOCK_WRITE)
611992ec6994e6050e4970a973d2f549f823a3eavboxsync f |= LOCK_EX;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync else
611992ec6994e6050e4970a973d2f549f823a3eavboxsync f |= LOCK_SH;
cae3b8810c39392e70dfb12b951431018a80fcbavboxsync if (!flock(RTFileToNative(hFile), f))
611992ec6994e6050e4970a973d2f549f823a3eavboxsync return VINF_SUCCESS;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync iErr = errno;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync if (iErr == EWOULDBLOCK)
611992ec6994e6050e4970a973d2f549f823a3eavboxsync return VERR_FILE_LOCK_VIOLATION;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync }
611992ec6994e6050e4970a973d2f549f823a3eavboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync if ( iErr == EAGAIN
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync || iErr == EACCES)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VERR_FILE_LOCK_VIOLATION;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return RTErrConvertFromErrno(iErr);
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync}
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
cae3b8810c39392e70dfb12b951431018a80fcbavboxsyncRTR3DECL(int) RTFileChangeLock(RTFILE hFile, unsigned fLock, int64_t offLock, uint64_t cbLock)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync{
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync /** @todo We never returns VERR_FILE_NOT_LOCKED for now. */
cae3b8810c39392e70dfb12b951431018a80fcbavboxsync return RTFileLock(hFile, fLock, offLock, cbLock);
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync}
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
cae3b8810c39392e70dfb12b951431018a80fcbavboxsyncRTR3DECL(int) RTFileUnlock(RTFILE hFile, int64_t offLock, uint64_t cbLock)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync{
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync Assert(offLock >= 0);
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync /*
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync * Validate offset.
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync if ( sizeof(off_t) < sizeof(cbLock)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync && ( (offLock >> 32) != 0
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync || (cbLock >> 32) != 0
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync || ((offLock + cbLock) >> 32) != 0))
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync {
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync AssertMsgFailed(("64-bit file i/o not supported! offLock=%lld cbLock=%lld\n", offLock, cbLock));
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VERR_NOT_SUPPORTED;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync }
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync /* Prepare flock structure. */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync struct flock fl;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_type = F_UNLCK;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_whence = SEEK_SET;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_start = (off_t)offLock;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_len = (off_t)cbLock;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync fl.l_pid = 0;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
cae3b8810c39392e70dfb12b951431018a80fcbavboxsync if (fcntl(RTFileToNative(hFile), F_SETLK, &fl) >= 0)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VINF_SUCCESS;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync int iErr = errno;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync if (iErr == ENOTSUP)
611992ec6994e6050e4970a973d2f549f823a3eavboxsync {
611992ec6994e6050e4970a973d2f549f823a3eavboxsync /* A SMB hack, see RTFileLock. */
cae3b8810c39392e70dfb12b951431018a80fcbavboxsync if (!flock(RTFileToNative(hFile), LOCK_UN))
611992ec6994e6050e4970a973d2f549f823a3eavboxsync return VINF_SUCCESS;
611992ec6994e6050e4970a973d2f549f823a3eavboxsync }
611992ec6994e6050e4970a973d2f549f823a3eavboxsync
611992ec6994e6050e4970a973d2f549f823a3eavboxsync /** @todo check error codes for non existing lock. */
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync if ( iErr == EAGAIN
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync || iErr == EACCES)
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return VERR_FILE_LOCK_VIOLATION;
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync return RTErrConvertFromErrno(iErr);
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync}
c7945191b700920f0ab9b951ce92cc69cb48ffb4vboxsync