LLVM  3.7.0
Public Member Functions | Static Public Member Functions | List of all members
llvm::sys::DynamicLibrary Class Reference

This class provides a portable interface to dynamic libraries which also might be known as shared libraries, shared objects, dynamic shared objects, or dynamic link libraries. More...

#include <DynamicLibrary.h>

Public Member Functions

 DynamicLibrary (void *data=&Invalid)
 
bool isValid () const
 Returns true if the object refers to a valid library. More...
 
void * getAddressOfSymbol (const char *symbolName)
 Searches through the library for the symbol symbolName. More...
 

Static Public Member Functions

static DynamicLibrary getPermanentLibrary (const char *filename, std::string *errMsg=nullptr)
 This function permanently loads the dynamic library at the given path. More...
 
static bool LoadLibraryPermanently (const char *Filename, std::string *ErrMsg=nullptr)
 This function permanently loads the dynamic library at the given path. More...
 
static void * SearchForAddressOfSymbol (const char *symbolName)
 This function will search through all previously loaded dynamic libraries for the symbol symbolName. More...
 
static void * SearchForAddressOfSymbol (const std::string &symbolName)
 Convenience function for C++ophiles. More...
 
static void AddSymbol (StringRef symbolName, void *symbolValue)
 This functions permanently adds the symbol symbolName with the value symbolValue. More...
 

Detailed Description

This class provides a portable interface to dynamic libraries which also might be known as shared libraries, shared objects, dynamic shared objects, or dynamic link libraries.

Regardless of the terminology or the operating system interface, this class provides a portable interface that allows dynamic libraries to be loaded and searched for externally defined symbols. This is typically used to provide "plug-in" support. It also allows for symbols to be defined which don't live in any library, but rather the main program itself, useful on Windows where the main executable cannot be searched.

Note: there is currently no interface for temporarily loading a library, or for unloading libraries when the LLVM library is unloaded.

Definition at line 37 of file DynamicLibrary.h.

Constructor & Destructor Documentation

llvm::sys::DynamicLibrary::DynamicLibrary ( void *  data = &Invalid)
inlineexplicit

Definition at line 47 of file DynamicLibrary.h.

Member Function Documentation

void llvm::sys::DynamicLibrary::AddSymbol ( StringRef  symbolName,
void *  symbolValue 
)
static

This functions permanently adds the symbol symbolName with the value symbolValue.

These symbols are searched before any libraries. Add searchable symbol/value pair.

Definition at line 30 of file DynamicLibrary.cpp.

Referenced by LLVMAddSymbol().

void * DynamicLibrary::getAddressOfSymbol ( const char *  symbolName)

Searches through the library for the symbol symbolName.

If it is found, the address of that symbol is returned. If not, NULL is returned. Note that NULL will also be returned if the library failed to load. Use isValid() to distinguish these cases if it is important. Note that this will not search symbols explicitly registered by AddSymbol().

Definition at line 84 of file DynamicLibrary.cpp.

References llvm::Data.

DynamicLibrary DynamicLibrary::getPermanentLibrary ( const char *  filename,
std::string *  errMsg = nullptr 
)
static

This function permanently loads the dynamic library at the given path.

The library will only be unloaded when the program terminates. This returns a valid DynamicLibrary instance on success and an invalid instance on failure (see isValid()). *errMsg will only be modified if the library fails to load.

It is safe to call this function multiple times for the same library. Open a dynamic library permanently.

Definition at line 56 of file DynamicLibrary.cpp.

References OpenedHandles.

Referenced by LoadLibraryPermanently().

bool llvm::sys::DynamicLibrary::isValid ( ) const
inline

Returns true if the object refers to a valid library.

Definition at line 50 of file DynamicLibrary.h.

Referenced by LoadLibraryPermanently().

static bool llvm::sys::DynamicLibrary::LoadLibraryPermanently ( const char *  Filename,
std::string *  ErrMsg = nullptr 
)
inlinestatic

This function permanently loads the dynamic library at the given path.

Use this instead of getPermanentLibrary() when you won't need to get symbols from the library itself.

It is safe to call this function multiple times for the same library.

Definition at line 76 of file DynamicLibrary.h.

References getPermanentLibrary(), and isValid().

Referenced by llvm::EngineBuilder::create(), llvm::MCJIT::createJIT(), LLVMLoadLibraryPermanently(), and llvm::PluginLoader::operator=().

void * DynamicLibrary::SearchForAddressOfSymbol ( const char *  symbolName)
static

This function will search through all previously loaded dynamic libraries for the symbol symbolName.

If it is found, the address of that symbol is returned. If not, null is returned. Note that this will search permanently loaded libraries (getPermanentLibrary()) as well as explicitly registered symbols (AddSymbol()).

Exceptions
std::stringon error. Search through libraries for address of a symbol

Definition at line 111 of file DynamicLibrary.cpp.

References EXPLICIT_SYMBOL, I, llvm::ManagedStaticBase::isConstructed(), Lock, OpenedHandles, and llvm::SearchForAddressOfSpecialSymbol().

Referenced by llvm::__deregister_frame(), llvm::__register_frame(), llvm::Interpreter::callExternalFunction(), llvm::ExecutionEngine::emitGlobals(), llvm::RTDyldMemoryManager::getSymbolAddressInProcess(), LLVMSearchForAddressOfSymbol(), lookupFunction(), and SearchForAddressOfSymbol().

static void* llvm::sys::DynamicLibrary::SearchForAddressOfSymbol ( const std::string &  symbolName)
inlinestatic

Convenience function for C++ophiles.

Definition at line 91 of file DynamicLibrary.h.

References SearchForAddressOfSymbol().


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