ultimatepp/bazaar/plugin/gdal/port/cplgetsymbol.cpp
cxl 23ff1e7e82 .gdal moved to bazaar
git-svn-id: svn://ultimatepp.org/upp/trunk@9273 f0d560ea-af0d-0410-9eb7-867de7ffcac7
2015-12-07 13:36:24 +00:00

250 lines
8.8 KiB
C++

/******************************************************************************
* $Id: cplgetsymbol.cpp 27460 2014-06-18 12:36:06Z rouault $
*
* Project: Common Portability Library
* Purpose: Fetch a function pointer from a shared library / DLL.
* Author: Frank Warmerdam, warmerdam@pobox.com
*
******************************************************************************
* Copyright (c) 1999, Frank Warmerdam
* Copyright (c) 2009-2013, Even Rouault <even dot rouault at mines-paris dot org>
*
* 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.
****************************************************************************/
#include "cpl_conv.h"
CPL_CVSID("$Id: cplgetsymbol.cpp 27460 2014-06-18 12:36:06Z rouault $");
/* ==================================================================== */
/* Unix Implementation */
/* ==================================================================== */
/* MinGW32 might define HAVE_DLFCN_H, so skip the unix implementation */
#if defined(HAVE_DLFCN_H) && !defined(WIN32)
#define GOT_GETSYMBOL
#include <dlfcn.h>
/************************************************************************/
/* CPLGetSymbol() */
/************************************************************************/
/**
* Fetch a function pointer from a shared library / DLL.
*
* This function is meant to abstract access to shared libraries and
* DLLs and performs functions similar to dlopen()/dlsym() on Unix and
* LoadLibrary() / GetProcAddress() on Windows.
*
* If no support for loading entry points from a shared library is available
* this function will always return NULL. Rules on when this function
* issues a CPLError() or not are not currently well defined, and will have
* to be resolved in the future.
*
* Currently CPLGetSymbol() doesn't try to:
* <ul>
* <li> prevent the reference count on the library from going up
* for every request, or given any opportunity to unload
* the library.
* <li> Attempt to look for the library in non-standard
* locations.
* <li> Attempt to try variations on the symbol name, like
* pre-prending or post-pending an underscore.
* </ul>
*
* Some of these issues may be worked on in the future.
*
* @param pszLibrary the name of the shared library or DLL containing
* the function. May contain path to file. If not system supplies search
* paths will be used.
* @param pszSymbolName the name of the function to fetch a pointer to.
* @return A pointer to the function if found, or NULL if the function isn't
* found, or the shared library can't be loaded.
*/
void *CPLGetSymbol( const char * pszLibrary, const char * pszSymbolName )
{
void *pLibrary;
void *pSymbol;
pLibrary = dlopen(pszLibrary, RTLD_LAZY);
if( pLibrary == NULL )
{
CPLError( CE_Failure, CPLE_AppDefined,
"%s", dlerror() );
return NULL;
}
pSymbol = dlsym( pLibrary, pszSymbolName );
#if (defined(__APPLE__) && defined(__MACH__))
/* On mach-o systems, C symbols have a leading underscore and depending
* on how dlcompat is configured it may or may not add the leading
* underscore. So if dlsym() fails add an underscore and try again.
*/
if( pSymbol == NULL )
{
char withUnder[strlen(pszSymbolName) + 2];
withUnder[0] = '_'; withUnder[1] = 0;
strcat(withUnder, pszSymbolName);
pSymbol = dlsym( pLibrary, withUnder );
}
#endif
if( pSymbol == NULL )
{
CPLError( CE_Failure, CPLE_AppDefined,
"%s", dlerror() );
return NULL;
}
return( pSymbol );
}
#endif /* def __unix__ && defined(HAVE_DLFCN_H) */
/* ==================================================================== */
/* Windows Implementation */
/* ==================================================================== */
#if defined(WIN32) && !defined(WIN32CE)
#define GOT_GETSYMBOL
#include <windows.h>
/************************************************************************/
/* CPLGetSymbol() */
/************************************************************************/
void *CPLGetSymbol( const char * pszLibrary, const char * pszSymbolName )
{
void *pLibrary;
void *pSymbol;
UINT uOldErrorMode;
/* Avoid error boxes to pop up (#5211, #5525) */
uOldErrorMode = SetErrorMode(SEM_NOOPENFILEERRORBOX | SEM_FAILCRITICALERRORS);
pLibrary = LoadLibrary(pszLibrary);
if( pLibrary <= (void*)HINSTANCE_ERROR )
{
LPVOID lpMsgBuf = NULL;
int nLastError = GetLastError();
/* Restore old error mode */
SetErrorMode(uOldErrorMode);
FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER
| FORMAT_MESSAGE_FROM_SYSTEM
| FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, nLastError,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR) &lpMsgBuf, 0, NULL );
CPLError( CE_Failure, CPLE_AppDefined,
"Can't load requested DLL: %s\n%d: %s",
pszLibrary, nLastError, (const char *) lpMsgBuf );
return NULL;
}
/* Restore old error mode */
SetErrorMode(uOldErrorMode);
pSymbol = (void *) GetProcAddress( (HINSTANCE) pLibrary, pszSymbolName );
if( pSymbol == NULL )
{
CPLError( CE_Failure, CPLE_AppDefined,
"Can't find requested entry point: %s\n", pszSymbolName );
return NULL;
}
return( pSymbol );
}
#endif /* def _WIN32 */
/* ==================================================================== */
/* Windows CE Implementation */
/* ==================================================================== */
#if defined(WIN32CE)
#define GOT_GETSYMBOL
#include "cpl_win32ce_api.h"
/************************************************************************/
/* CPLGetSymbol() */
/************************************************************************/
void *CPLGetSymbol( const char * pszLibrary, const char * pszSymbolName )
{
void *pLibrary;
void *pSymbol;
pLibrary = CE_LoadLibraryA(pszLibrary);
if( pLibrary == NULL )
{
CPLError( CE_Failure, CPLE_AppDefined,
"Can't load requested DLL: %s", pszLibrary );
return NULL;
}
pSymbol = (void *) CE_GetProcAddressA( (HINSTANCE) pLibrary, pszSymbolName );
if( pSymbol == NULL )
{
CPLError( CE_Failure, CPLE_AppDefined,
"Can't find requested entry point: %s\n", pszSymbolName );
return NULL;
}
return( pSymbol );
}
#endif /* def WIN32CE */
/* ==================================================================== */
/* Dummy implementation. */
/* ==================================================================== */
#ifndef GOT_GETSYMBOL
/************************************************************************/
/* CPLGetSymbol() */
/* */
/* Dummy implementation. */
/************************************************************************/
void *CPLGetSymbol(const char *pszLibrary, const char *pszEntryPoint)
{
CPLDebug( "CPL",
"CPLGetSymbol(%s,%s) called. Failed as this is stub"
" implementation.", pszLibrary, pszEntryPoint );
return NULL;
}
#endif