VBoxXPCOMCGlue.c revision 5c65eaa08f2ec993a19c9bef6e5463918e40e0eb
/* $Revision$ */
/** @file
* Glue code for dynamically linking to VBoxXPCOMC.
*/
/*
* Copyright (C) 2008-2010 Oracle Corporation
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdint.h>
#include <dlfcn.h>
#include "VBoxXPCOMCGlue.h"
/*******************************************************************************
* Defined Constants And Macros *
*******************************************************************************/
#if defined(__linux__) || defined(__linux_gnu__) || defined(__sun__) || defined(__FreeBSD__)
# define DYNLIB_NAME "VBoxXPCOMC.so"
#elif defined(__APPLE__)
# define DYNLIB_NAME "VBoxXPCOMC.dylib"
#elif defined(_MSC_VER) || defined(__OS2__)
# define DYNLIB_NAME "VBoxXPCOMC.dll"
#else
# error "Port me"
#endif
/*******************************************************************************
* Global Variables *
*******************************************************************************/
/** The dlopen handle for VBoxXPCOMC. */
void *g_hVBoxXPCOMC = NULL;
/** The last load error. */
char g_szVBoxErrMsg[256];
/** Pointer to the VBoxXPCOMC function table. */
PCVBOXXPCOM g_pVBoxFuncs = NULL;
/** Pointer to VBoxGetXPCOMCFunctions for the loaded VBoxXPCOMC so/dylib/dll. */
PFNVBOXGETXPCOMCFUNCTIONS g_pfnGetFunctions = NULL;
/**
* Wrapper for setting g_szVBoxErrMsg. Can be an empty stub.
*
* @param fAlways When 0 the g_szVBoxErrMsg is only set if empty.
* @param pszFormat The format string.
* @param ... The arguments.
*/
static void setErrMsg(int fAlways, const char *pszFormat, ...)
{
if ( fAlways
|| !g_szVBoxErrMsg[0])
{
va_list va;
va_start(va, pszFormat);
vsnprintf(g_szVBoxErrMsg, sizeof(g_szVBoxErrMsg), pszFormat, va);
va_end(va);
}
}
/**
* Try load VBoxXPCOMC.so/dylib/dll from the specified location and resolve all
* the symbols we need.
*
* @returns 0 on success, -1 on failure.
* @param pszHome The director where to try load VBoxXPCOMC from. Can
* be NULL.
* @param fSetAppHome Whether to set the VBOX_APP_HOME env.var. or not
* (boolean).
*/
static int tryLoadOne(const char *pszHome, int fSetAppHome)
{
size_t cchHome = pszHome ? strlen(pszHome) : 0;
size_t cbBufNeeded;
char szName[4096];
int rc = -1;
/*
* Construct the full name.
*/
cbBufNeeded = cchHome + sizeof("/" DYNLIB_NAME);
if (cbBufNeeded > sizeof(szName))
{
setErrMsg(1, "path buffer too small: %u bytes needed",
(unsigned)cbBufNeeded);
return -1;
}
if (cchHome)
{
memcpy(szName, pszHome, cchHome);
szName[cchHome] = '/';
cchHome++;
}
memcpy(&szName[cchHome], DYNLIB_NAME, sizeof(DYNLIB_NAME));
/*
* Try load it by that name, setting the VBOX_APP_HOME first (for now).
* Then resolve and call the function table getter.
*/
if (fSetAppHome)
{
if (pszHome)
setenv("VBOX_APP_HOME", pszHome, 1 /* always override */);
else
unsetenv("VBOX_APP_HOME");
}
g_hVBoxXPCOMC = dlopen(szName, RTLD_NOW | RTLD_LOCAL);
if (g_hVBoxXPCOMC)
{
PFNVBOXGETXPCOMCFUNCTIONS pfnGetFunctions;
pfnGetFunctions = (PFNVBOXGETXPCOMCFUNCTIONS)(uintptr_t)
dlsym(g_hVBoxXPCOMC, VBOX_GET_XPCOMC_FUNCTIONS_SYMBOL_NAME);
if (pfnGetFunctions)
{
g_pVBoxFuncs = pfnGetFunctions(VBOX_XPCOMC_VERSION);
if (g_pVBoxFuncs)
{
g_pfnGetFunctions = pfnGetFunctions;
return 0;
}
/* bail out */
setErrMsg(1, "%.80s: pfnGetFunctions(%#x) failed",
szName, VBOX_XPCOMC_VERSION);
}
else
setErrMsg(1, "dlsym(%.80s/%.32s): %.128s",
szName, VBOX_GET_XPCOMC_FUNCTIONS_SYMBOL_NAME, dlerror());
dlclose(g_hVBoxXPCOMC);
g_hVBoxXPCOMC = NULL;
}
else
setErrMsg(0, "dlopen(%.80s): %.160s", szName, dlerror());
return rc;
}
/**
* Tries to locate and load VBoxXPCOMC.so/dylib/dll, resolving all the related
* function pointers.
*
* @returns 0 on success, -1 on failure.
*
* @remark This should be considered moved into a separate glue library since
* its its going to be pretty much the same for any user of VBoxXPCOMC
* and it will just cause trouble to have duplicate versions of this
* source code all around the place.
*/
int VBoxCGlueInit(void)
{
/*
* If the user specifies the location, try only that.
*/
const char *pszHome = getenv("VBOX_APP_HOME");
if (pszHome)
return tryLoadOne(pszHome, 0);
/*
* Try the known standard locations.
*/
g_szVBoxErrMsg[0] = '\0';
#if defined(__gnu__linux__) || defined(__linux__)
if (tryLoadOne("/opt/VirtualBox", 1) == 0)
return 0;
if (tryLoadOne("/usr/lib/virtualbox", 1) == 0)
return 0;
#elif defined(__sun__)
if (tryLoadOne("/opt/VirtualBox/amd64", 1) == 0)
return 0;
if (tryLoadOne("/opt/VirtualBox/i386", 1) == 0)
return 0;
#elif defined(__APPLE__)
if (tryLoadOne("/Application/VirtualBox.app/Contents/MacOS", 1) == 0)
return 0;
#elif defined(__FreeBSD__)
if (tryLoadOne("/usr/local/lib/virtualbox", 1) == 0)
return 0;
#else
# error "port me"
#endif
/*
* Finally try the dynamic linker search path.
*/
if (tryLoadOne(NULL, 1) == 0)
return 0;
/* No luck, return failure. */
return -1;
}
/**
* Terminate the C glue library.
*/
void VBoxCGlueTerm(void)
{
if (g_hVBoxXPCOMC)
{
#if 0 /* VBoxRT.so doesn't like being reloaded. See @bugref{3725}. */
dlclose(g_hVBoxXPCOMC);
#endif
g_hVBoxXPCOMC = NULL;
}
g_pVBoxFuncs = NULL;
g_pfnGetFunctions = NULL;
memset(g_szVBoxErrMsg, 0, sizeof(g_szVBoxErrMsg));
}