VBoxGuestR3LibLog.cpp revision e6660f4933111b0649ffa77483102881f4e75c3b
/* $Id$ */
/** @file
* VBoxGuestR3Lib - Ring-3 Support Library for VirtualBox guest additions, Logging.
*/
/*
* Copyright (C) 2007-2010 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 *
*******************************************************************************/
#include <iprt/mem.h>
#include "VBGLR3Internal.h"
/**
* Write to the backdoor logger from ring 3 guest code.
*
* @returns IPRT status code.
*
* @param pch The string to log. Does not need to be terminated.
* @param cch The number of chars (bytes) to log.
*
* @remarks This currently does not accept more than 255 bytes of data at
* one time. It should probably be rewritten to use pass a pointer
* in the IOCtl.
*/
VBGLR3DECL(int) VbglR3WriteLog(const char *pch, size_t cch)
{
/*
* Quietly skip NULL strings.
* (Happens in the RTLogBackdoorPrintf case.)
*/
if (!cch)
return VINF_SUCCESS;
if (!VALID_PTR(pch))
return VERR_INVALID_POINTER;
#ifdef RT_OS_WINDOWS
/*
* Duplicate the string as it may be read only (a C string).
*/
void *pvTmp = RTMemDup(pch, cch);
if (!pvTmp)
return VERR_NO_MEMORY;
int rc = vbglR3DoIOCtl(VBOXGUEST_IOCTL_LOG(cch), pvTmp, cch);
RTMemFree(pvTmp);
return rc;
#elif 0 /** @todo Several OSes could take this route (solaris and freebsd for instance). */
/*
* Handle the entire request in one go.
*/
return vbglR3DoIOCtl(VBOXGUEST_IOCTL_LOG(cch), pvTmp, cch);
#else
/*
* *BSD does not accept more than 4KB per ioctl request, while
* Linux can't express sizes above 8KB, so, split it up into 2KB chunks.
*/
# define STEP 2048
int rc = VINF_SUCCESS;
for (size_t off = 0; off < cch && RT_SUCCESS(rc); off += STEP)
{
size_t cbStep = RT_MIN(cch - off, STEP);
rc = vbglR3DoIOCtl(VBOXGUEST_IOCTL_LOG(cbStep), (char *)pch + off, cbStep);
}
# undef STEP
return rc;
#endif
}