nidas::core::DynamicLoader Class Reference

Class providing dynamic loader functionality of system functions dlopen() and dlsym() to look up symbols. More...

#include <DynamicLoader.h>

Public Member Functions
void *	lookup (const std::string &name)
	Search the main program itself, and its currently loaded libraries for a symbol.
void *	lookup (const std::string &library, const std::string &name)
	Return a pointer to a symbol from the given library.

Static Public Member Functions
static DynamicLoader *	getInstance ()
	Get a pointer to the singleton instance of DynamicLoader.

Private Member Functions
	DynamicLoader ()
	DynamicLoader (const DynamicLoader &)
	No copy.
DynamicLoader &	operator= (const DynamicLoader &)
	No assignment.
	~DynamicLoader ()

Private Attributes
void *	_defhandle
	Handle, returned by dlopen(), of the program itself, and its linked and dynamically loaded libraries.
std::map< std::string, void * >	_libhandles
	Handles, by library name, returned by dlopen() of libraries that are currently open, because one or more symbols have been found in them.

Static Private Attributes
static DynamicLoader *	_instance = 0
static nidas::util::Mutex	_instanceLock

Detailed Description

Class providing dynamic loader functionality of system functions dlopen() and dlsym() to look up symbols.

Constructor & Destructor Documentation

DynamicLoader() [1/2]

DynamicLoader::DynamicLoader ( )

private

Exceptions

nidas::util::Exception

References _defhandle, _libhandles, and nidas::core::getSample().

Referenced by getInstance().

DynamicLoader() [2/2]

nidas::core::DynamicLoader::DynamicLoader ( const DynamicLoader & )

private

No copy.

~DynamicLoader()

DynamicLoader::~DynamicLoader ( )

private

Member Function Documentation

getInstance()

DynamicLoader * DynamicLoader::getInstance ( )

static

Get a pointer to the singleton instance of DynamicLoader.

Exceptions

nidas::util::Exception

References _instance, _instanceLock, DynamicLoader(), and nidas::core::getSample().

Referenced by nidas::core::DOMObjectFactory::createObject().

lookup() [1/2]

void * DynamicLoader::lookup	(	const std::string &	library,
		const std::string &	name )

Return a pointer to a symbol from the given library.

@ param library: name of the library. @ param name: name of the symbol to look up.

If the library name is an empty string, then the libraries linked with the program, and any currently loaded dynamic libraries will be searched. If the library name is absolute (begins with a forward slash), then it is loaded. Otherwise a search for the library is done, using the program's library directory search path, which is controlled by compile time flags, the LD_LIBRARY_PATH environment variable, and ld.so/ldconfig/ld.so.conf. lookup() throws an exception if the library could not be found and loaded or the symbol could not be found in the library. If the symbol is found, the library will remain loaded, and symbols in that library can then be found via lookup(name), or by specifying an emptry string for the library.

Exceptions

nidas::util::Exception

References _instanceLock, _libhandles, and nidas::core::getSample().

lookup() [2/2]

void * DynamicLoader::lookup

(

const std::string &

name

)

Search the main program itself, and its currently loaded libraries for a symbol.

Throws an exception if the lookup fails.

Exceptions

nidas::util::Exception

References _defhandle, _instanceLock, and nidas::core::getSample().

operator=()

DynamicLoader & nidas::core::DynamicLoader::operator= ( const DynamicLoader & )

private

No assignment.

Member Data Documentation

_defhandle

void* nidas::core::DynamicLoader::_defhandle

private

Handle, returned by dlopen(), of the program itself, and its linked and dynamically loaded libraries.

Referenced by DynamicLoader(), and lookup().

_instance

DynamicLoader * DynamicLoader::_instance = 0

staticprivate

Referenced by getInstance().

_instanceLock

n_u::Mutex DynamicLoader::_instanceLock

staticprivate

Referenced by getInstance(), lookup(), and lookup().

_libhandles

std::map<std::string,void*> nidas::core::DynamicLoader::_libhandles

private

Handles, by library name, returned by dlopen() of libraries that are currently open, because one or more symbols have been found in them.

Referenced by DynamicLoader(), and lookup().

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The documentation for this class was generated from the following files:

• nidas/core/DynamicLoader.h
• nidas/core/DynamicLoader.cc