| 1 | /* $Id: filelock-os2.cpp 8245 2008-04-21 17:24:28Z vboxsync $ */
|
|---|
| 2 | /** @file
|
|---|
| 3 | * IPRT - File Locking, OS/2.
|
|---|
| 4 | */
|
|---|
| 5 |
|
|---|
| 6 | /*
|
|---|
| 7 | * Copyright (C) 2008 Sun Microsystems, Inc.
|
|---|
| 8 | *
|
|---|
| 9 | * This file is part of VirtualBox Open Source Edition (OSE), as
|
|---|
| 10 | * available from http://www.virtualbox.org. This file is free software;
|
|---|
| 11 | * you can redistribute it and/or modify it under the terms of the GNU
|
|---|
| 12 | * General Public License (GPL) as published by the Free Software
|
|---|
| 13 | * Foundation, in version 2 as it comes in the "COPYING" file of the
|
|---|
| 14 | * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
|
|---|
| 15 | * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
|
|---|
| 16 | *
|
|---|
| 17 | * The contents of this file may alternatively be used under the terms
|
|---|
| 18 | * of the Common Development and Distribution License Version 1.0
|
|---|
| 19 | * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
|
|---|
| 20 | * VirtualBox OSE distribution, in which case the provisions of the
|
|---|
| 21 | * CDDL are applicable instead of those of the GPL.
|
|---|
| 22 | *
|
|---|
| 23 | * You may elect to license modified versions of this file under the
|
|---|
| 24 | * terms and conditions of either the GPL or the CDDL or both.
|
|---|
| 25 | *
|
|---|
| 26 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
|
|---|
| 27 | * Clara, CA 95054 USA or visit http://www.sun.com if you need
|
|---|
| 28 | * additional information or have any questions.
|
|---|
| 29 | */
|
|---|
| 30 |
|
|---|
| 31 |
|
|---|
| 32 | /*******************************************************************************
|
|---|
| 33 | * Header Files *
|
|---|
| 34 | *******************************************************************************/
|
|---|
| 35 | #define LOG_GROUP RTLOGGROUP_FILE
|
|---|
| 36 |
|
|---|
| 37 | #include <errno.h>
|
|---|
| 38 | #include <sys/types.h>
|
|---|
| 39 | #include <sys/ioctl.h>
|
|---|
| 40 | #include <sys/fcntl.h>
|
|---|
| 41 | #include <fcntl.h>
|
|---|
| 42 | #include <unistd.h>
|
|---|
| 43 | #include <sys/time.h>
|
|---|
| 44 |
|
|---|
| 45 | #include <iprt/file.h>
|
|---|
| 46 | #include <iprt/assert.h>
|
|---|
| 47 | #include <iprt/string.h>
|
|---|
| 48 | #include <iprt/err.h>
|
|---|
| 49 | #include <iprt/log.h>
|
|---|
| 50 | #include "internal/file.h"
|
|---|
| 51 | #include "internal/fs.h"
|
|---|
| 52 |
|
|---|
| 53 |
|
|---|
| 54 |
|
|---|
| 55 |
|
|---|
| 56 | RTR3DECL(int) RTFileLock(RTFILE File, unsigned fLock, int64_t offLock, uint64_t cbLock)
|
|---|
| 57 | {
|
|---|
| 58 | Assert(offLock >= 0);
|
|---|
| 59 |
|
|---|
| 60 | /* Check arguments. */
|
|---|
| 61 | if (fLock & ~RTFILE_LOCK_MASK)
|
|---|
| 62 | {
|
|---|
| 63 | AssertMsgFailed(("Invalid fLock=%08X\n", fLock));
|
|---|
| 64 | return VERR_INVALID_PARAMETER;
|
|---|
| 65 | }
|
|---|
| 66 |
|
|---|
| 67 | /*
|
|---|
| 68 | * Validate offset.
|
|---|
| 69 | */
|
|---|
| 70 | if ( sizeof(off_t) < sizeof(cbLock)
|
|---|
| 71 | && ( (offLock >> 32) != 0
|
|---|
| 72 | || (cbLock >> 32) != 0
|
|---|
| 73 | || ((offLock + cbLock) >> 32) != 0))
|
|---|
| 74 | {
|
|---|
| 75 | AssertMsgFailed(("64-bit file i/o not supported! offLock=%lld cbLock=%lld\n", offLock, cbLock));
|
|---|
| 76 | return VERR_NOT_SUPPORTED;
|
|---|
| 77 | }
|
|---|
| 78 |
|
|---|
| 79 | /* Prepare flock structure. */
|
|---|
| 80 | struct flock fl;
|
|---|
| 81 | Assert(RTFILE_LOCK_WRITE);
|
|---|
| 82 | fl.l_type = (fLock & RTFILE_LOCK_WRITE) ? F_WRLCK : F_RDLCK;
|
|---|
| 83 | fl.l_whence = SEEK_SET;
|
|---|
| 84 | fl.l_start = (off_t)offLock;
|
|---|
| 85 | fl.l_len = (off_t)cbLock;
|
|---|
| 86 | fl.l_pid = 0;
|
|---|
| 87 |
|
|---|
| 88 | Assert(RTFILE_LOCK_WAIT);
|
|---|
| 89 | if (fcntl(File, (fLock & RTFILE_LOCK_WAIT) ? F_SETLKW : F_SETLK, &fl) >= 0)
|
|---|
| 90 | return VINF_SUCCESS;
|
|---|
| 91 |
|
|---|
| 92 | int iErr = errno;
|
|---|
| 93 | if ( iErr == EAGAIN
|
|---|
| 94 | || iErr == EACCES)
|
|---|
| 95 | return VERR_FILE_LOCK_VIOLATION;
|
|---|
| 96 |
|
|---|
| 97 | return RTErrConvertFromErrno(iErr);
|
|---|
| 98 | }
|
|---|
| 99 |
|
|---|
| 100 |
|
|---|
| 101 | RTR3DECL(int) RTFileChangeLock(RTFILE File, unsigned fLock, int64_t offLock, uint64_t cbLock)
|
|---|
| 102 | {
|
|---|
| 103 | /** @todo copied from ../win/fileio-win.cpp for now but a proper solution
|
|---|
| 104 | * would probably be to modify kLIBC so that __fcntl_locking() first
|
|---|
| 105 | * assmues a change lock request is made (e.g. the same region was
|
|---|
| 106 | * previously F_RDLCK'ed and now needs to be F_WRLCK'ed or vice versa) and
|
|---|
| 107 | * tries to use atomic locking, and only if it fails, it does the regular
|
|---|
| 108 | * lock procedure. The alternative is to use DosSetFileLocks directly here
|
|---|
| 109 | * which basically means copy-pasting the __fcntl_locking() source
|
|---|
| 110 | * code :) Note that the first attempt to call RTFileLock() below assumes
|
|---|
| 111 | * that kLIBC is patched as described above one day and gives it a chance;
|
|---|
| 112 | * on failure, we fall back to the Win-like unlock-then-lock approach. */
|
|---|
| 113 |
|
|---|
| 114 | int rc = RTFileLock(File, fLock, offLock, cbLock);
|
|---|
| 115 | if (RT_FAILURE(rc) && rc != VERR_FILE_LOCK_VIOLATION)
|
|---|
| 116 | return rc;
|
|---|
| 117 |
|
|---|
| 118 | /* Check arguments. */
|
|---|
| 119 | if (fLock & ~RTFILE_LOCK_MASK)
|
|---|
| 120 | {
|
|---|
| 121 | AssertMsgFailed(("Invalid fLock=%08X\n", fLock));
|
|---|
| 122 | return VERR_INVALID_PARAMETER;
|
|---|
| 123 | }
|
|---|
| 124 |
|
|---|
| 125 | /* Remove old lock. */
|
|---|
| 126 | rc = RTFileUnlock(File, offLock, cbLock);
|
|---|
| 127 | if (RT_FAILURE(rc))
|
|---|
| 128 | return rc;
|
|---|
| 129 |
|
|---|
| 130 | /* Set new lock. */
|
|---|
| 131 | rc = RTFileLock(File, fLock, offLock, cbLock);
|
|---|
| 132 | if (RT_SUCCESS(rc))
|
|---|
| 133 | return rc;
|
|---|
| 134 |
|
|---|
| 135 | /* Try to restore old lock. */
|
|---|
| 136 | unsigned fLockOld = (fLock & RTFILE_LOCK_WRITE) ? fLock & ~RTFILE_LOCK_WRITE : fLock | RTFILE_LOCK_WRITE;
|
|---|
| 137 | rc = RTFileLock(File, fLockOld, offLock, cbLock);
|
|---|
| 138 | if (RT_SUCCESS(rc))
|
|---|
| 139 | return VERR_FILE_LOCK_VIOLATION;
|
|---|
| 140 | else
|
|---|
| 141 | return VERR_FILE_LOCK_LOST;
|
|---|
| 142 | }
|
|---|
| 143 |
|
|---|
| 144 |
|
|---|
| 145 | RTR3DECL(int) RTFileUnlock(RTFILE File, int64_t offLock, uint64_t cbLock)
|
|---|
| 146 | {
|
|---|
| 147 | Assert(offLock >= 0);
|
|---|
| 148 |
|
|---|
| 149 | /*
|
|---|
| 150 | * Validate offset.
|
|---|
| 151 | */
|
|---|
| 152 | if ( sizeof(off_t) < sizeof(cbLock)
|
|---|
| 153 | && ( (offLock >> 32) != 0
|
|---|
| 154 | || (cbLock >> 32) != 0
|
|---|
| 155 | || ((offLock + cbLock) >> 32) != 0))
|
|---|
| 156 | {
|
|---|
| 157 | AssertMsgFailed(("64-bit file i/o not supported! offLock=%lld cbLock=%lld\n", offLock, cbLock));
|
|---|
| 158 | return VERR_NOT_SUPPORTED;
|
|---|
| 159 | }
|
|---|
| 160 |
|
|---|
| 161 | /* Prepare flock structure. */
|
|---|
| 162 | struct flock fl;
|
|---|
| 163 | fl.l_type = F_UNLCK;
|
|---|
| 164 | fl.l_whence = SEEK_SET;
|
|---|
| 165 | fl.l_start = (off_t)offLock;
|
|---|
| 166 | fl.l_len = (off_t)cbLock;
|
|---|
| 167 | fl.l_pid = 0;
|
|---|
| 168 |
|
|---|
| 169 | if (fcntl(File, F_SETLK, &fl) >= 0)
|
|---|
| 170 | return VINF_SUCCESS;
|
|---|
| 171 |
|
|---|
| 172 | /** @todo check error codes for non existing lock. */
|
|---|
| 173 | int iErr = errno;
|
|---|
| 174 | if ( iErr == EAGAIN
|
|---|
| 175 | || iErr == EACCES)
|
|---|
| 176 | return VERR_FILE_LOCK_VIOLATION;
|
|---|
| 177 |
|
|---|
| 178 | return RTErrConvertFromErrno(iErr);
|
|---|
| 179 | }
|
|---|
| 180 |
|
|---|
