Imported 2.1.2-dfsgupstream/2.1.2-dfsg

1 files changed, 180 insertions, 0 deletions

diff --git a/src/VBox/Runtime/r3/os2/filelock-os2.cpp b/src/VBox/Runtime/r3/os2/filelock-os2.cpp
new file mode 100644
index 000000000..b6e33cfce
--- /dev/null
+++ b/src/VBox/Runtime/r3/os2/filelock-os2.cpp
@@ -0,0 +1,180 @@
+/* $Id: filelock-os2.cpp 8245 2008-04-21 17:24:28Z vboxsync $ */
+/** @file
+ * IPRT - File Locking, OS/2.
+ */
+
+/*
+ * Copyright (C) 2008 Sun Microsystems, Inc.
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
+ * Clara, CA 95054 USA or visit http://www.sun.com if you need
+ * additional information or have any questions.
+ */
+
+
+/*******************************************************************************
+*   Header Files                                                               *
+*******************************************************************************/
+#define LOG_GROUP RTLOGGROUP_FILE
+
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/fcntl.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+#include <iprt/file.h>
+#include <iprt/assert.h>
+#include <iprt/string.h>
+#include <iprt/err.h>
+#include <iprt/log.h>
+#include "internal/file.h"
+#include "internal/fs.h"
+
+
+
+
+RTR3DECL(int)  RTFileLock(RTFILE File, unsigned fLock, int64_t offLock, uint64_t cbLock)
+{
+    Assert(offLock >= 0);
+
+    /* Check arguments. */
+    if (fLock & ~RTFILE_LOCK_MASK)
+    {
+        AssertMsgFailed(("Invalid fLock=%08X\n", fLock));
+        return VERR_INVALID_PARAMETER;
+    }
+
+    /*
+     * Validate offset.
+     */
+    if (    sizeof(off_t) < sizeof(cbLock)
+        &&  (    (offLock >> 32) != 0
+             ||  (cbLock >> 32) != 0
+             ||  ((offLock + cbLock) >> 32) != 0))
+    {
+        AssertMsgFailed(("64-bit file i/o not supported! offLock=%lld cbLock=%lld\n", offLock, cbLock));
+        return VERR_NOT_SUPPORTED;
+    }
+
+    /* Prepare flock structure. */
+    struct flock fl;
+    Assert(RTFILE_LOCK_WRITE);
+    fl.l_type   = (fLock & RTFILE_LOCK_WRITE) ? F_WRLCK : F_RDLCK;
+    fl.l_whence = SEEK_SET;
+    fl.l_start  = (off_t)offLock;
+    fl.l_len    = (off_t)cbLock;
+    fl.l_pid    = 0;
+
+    Assert(RTFILE_LOCK_WAIT);
+    if (fcntl(File, (fLock & RTFILE_LOCK_WAIT) ? F_SETLKW : F_SETLK, &fl) >= 0)
+        return VINF_SUCCESS;
+
+    int iErr = errno;
+    if (    iErr == EAGAIN
+        ||  iErr == EACCES)
+        return VERR_FILE_LOCK_VIOLATION;
+
+    return RTErrConvertFromErrno(iErr);
+}
+
+
+RTR3DECL(int)  RTFileChangeLock(RTFILE File, unsigned fLock, int64_t offLock, uint64_t cbLock)
+{
+    /** @todo copied from ../win/fileio-win.cpp for now but a proper solution
+     * would probably be to modify kLIBC so that __fcntl_locking() first
+     * assmues a change lock request is made (e.g. the same region was
+     * previously F_RDLCK'ed and now needs to be F_WRLCK'ed or vice versa) and
+     * tries to use atomic locking, and only if it fails, it does the regular
+     * lock procedure. The alternative is to use DosSetFileLocks directly here
+     * which basically means copy-pasting the __fcntl_locking() source
+     * code :) Note that the first attempt to call RTFileLock() below assumes
+     * that kLIBC is patched as described above one day and gives it a chance;
+     * on failure, we fall back to the Win-like unlock-then-lock approach. */
+
+    int rc = RTFileLock(File, fLock, offLock, cbLock);
+    if (RT_FAILURE(rc) && rc != VERR_FILE_LOCK_VIOLATION)
+        return rc;
+
+    /* Check arguments. */
+    if (fLock & ~RTFILE_LOCK_MASK)
+    {
+        AssertMsgFailed(("Invalid fLock=%08X\n", fLock));
+        return VERR_INVALID_PARAMETER;
+    }
+
+    /* Remove old lock. */
+    rc = RTFileUnlock(File, offLock, cbLock);
+    if (RT_FAILURE(rc))
+        return rc;
+
+    /* Set new lock. */
+    rc = RTFileLock(File, fLock, offLock, cbLock);
+    if (RT_SUCCESS(rc))
+        return rc;
+
+    /* Try to restore old lock. */
+    unsigned fLockOld = (fLock & RTFILE_LOCK_WRITE) ? fLock & ~RTFILE_LOCK_WRITE : fLock | RTFILE_LOCK_WRITE;
+    rc = RTFileLock(File, fLockOld, offLock, cbLock);
+    if (RT_SUCCESS(rc))
+        return VERR_FILE_LOCK_VIOLATION;
+    else
+        return VERR_FILE_LOCK_LOST;
+}
+
+
+RTR3DECL(int)  RTFileUnlock(RTFILE File, int64_t offLock, uint64_t cbLock)
+{
+    Assert(offLock >= 0);
+
+    /*
+     * Validate offset.
+     */
+    if (    sizeof(off_t) < sizeof(cbLock)
+        &&  (    (offLock >> 32) != 0
+             ||  (cbLock >> 32) != 0
+             ||  ((offLock + cbLock) >> 32) != 0))
+    {
+        AssertMsgFailed(("64-bit file i/o not supported! offLock=%lld cbLock=%lld\n", offLock, cbLock));
+        return VERR_NOT_SUPPORTED;
+    }
+
+    /* Prepare flock structure. */
+    struct flock fl;
+    fl.l_type   = F_UNLCK;
+    fl.l_whence = SEEK_SET;
+    fl.l_start  = (off_t)offLock;
+    fl.l_len    = (off_t)cbLock;
+    fl.l_pid    = 0;
+
+    if (fcntl(File, F_SETLK, &fl) >= 0)
+        return VINF_SUCCESS;
+
+    /** @todo check error codes for non existing lock. */
+    int iErr = errno;
+    if (    iErr == EAGAIN
+        ||  iErr == EACCES)
+        return VERR_FILE_LOCK_VIOLATION;
+
+    return RTErrConvertFromErrno(iErr);
+}
+