X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=include%2Fdynamic.h;h=727ed11e1576b37856426e0f35840010aea97358;hb=c84ad4cc16452b86bb444a22a55203afa4fa5454;hp=0382324ce435774e1cfe3eebff1666495033507e;hpb=e81bad456aa55af8b0cb31d2ffeb0672ff0c6bbf;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/include/dynamic.h b/include/dynamic.h index 0382324ce..727ed11e1 100644 --- a/include/dynamic.h +++ b/include/dynamic.h @@ -1,105 +1,159 @@ +/* +------------------------------------+ + * | Inspire Internet Relay Chat Daemon | + * +------------------------------------+ + * + * InspIRCd: (C) 2002-2008 InspIRCd Development Team + * See: http://www.inspircd.org/wiki/index.php/Credits + * + * This program is free but copyrighted software; see + * the file COPYING for details. + * + * --------------------------------------------------- + */ + #ifndef __DLL_H #define __DLL_H -// -// class DLLManager is the simple ELF C++ Library manager. -// -// It tries to dynamically load the specified shared library -// when it is construted. -// -// You should call LastError() before doing anything. If it -// returns NULL there is no error. -// - - -class DLLManager +/** The DLLManager class is able to load a module file by filename, + * and locate its init_module symbol. + */ +class CoreExport DLLManager { + protected: + + /** The last error string, or NULL + */ + const char *err; + public: - DLLManager( const char *fname ); + /** This constructor loads the module using dlopen() + * @param ServerInstance The creator class of this object + * @param fname The filename to load. This should be within + * the modules dir. + */ + DLLManager(InspIRCd* ServerInstance, const char *fname); virtual ~DLLManager(); - - bool GetSymbol( void **, const char *sym_name ); - - const char *LastError() + /** Get a symbol using dynamic linking. + * @param v A function pointer, pointing at an init_module function + * @param sym_name The symbol name to find, usually "init_module" + * @return true if the symbol can be found, also the symbol will be put into v. + */ + bool GetSymbol(void **v, const char *sym_name); + + /** Get the last error from dlopen() or dlsym(). + * @return The last error string, or NULL if no error has occured. + */ + const char* LastError() { return err; } - - protected: + + /** The module handle. + * This is OS dependent, on POSIX platforms it is a pointer to a function + * pointer (yes, really!) and on windows it is a library handle. + */ void *h; - const char *err; }; - -// -// class DLLFactoryBase is the base class used for the DLLFactory -// template class. -// -// It inherits from the DLLManager class and must be constructed with -// the file name of the shared library and the function name within that -// library which will create the desired C++ factory class. -// If you do not provide func_name to the constructor, it defaults to -// the undecorated "C" symbol "factory0" -// -// factory_func will be set to a pointer to the requested factory creator -// function. If there was an error linking to the shared library, -// factory_func will be 0. -// -// You can call 'LastError()' to find the error message that occurred. -// -// - -class DLLFactoryBase : public DLLManager +class CoreExport LoadModuleException : public CoreException { public: - DLLFactoryBase(const char *fname, const char *func_name = 0); - virtual ~DLLFactoryBase(); - void * (*factory_func)(void); + /** This constructor can be used to specify an error message before throwing. + */ + LoadModuleException(const std::string &message) + : CoreException(message, "the core") + { + } + + /** This destructor solves world hunger, cancels the world debt, and causes the world to end. + * Actually no, it does nothing. Never mind. + * @throws Nothing! + */ + virtual ~LoadModuleException() throw() {}; }; +class CoreExport FindSymbolException : public CoreException +{ + public: + /** This constructor can be used to specify an error message before throwing. + */ + FindSymbolException(const std::string &message) + : CoreException(message, "the core") + { + } + + /** This destructor solves world hunger, cancels the world debt, and causes the world to end. + * Actually no, it does nothing. Never mind. + * @throws Nothing! + */ + virtual ~FindSymbolException() throw() {}; +}; -// -// The DLLFactory template class inherits from DLLFactoryBase. -// The constructor takes the file name of the shared library -// and the undecorated "C" symbol name of the factory creator -// function. The factory creator function in your shared library -// MUST either return a pointer to an object that is a subclass -// of 'T' or it must return 0. -// -// If everything is cool, then 'factory' will point to the -// requested factory class. If not, it will be 0. -// -// Since the DLLFactory template ultimately inherits DLLManager, -// you can call LastError() to get any error code information -// -// The created factory is OWNED by the DLLFactory class. -// The created factory will get deleted when the DLLFactory class -// is deleted, because the DLL will get unloaded as well. -// - -template class DLLFactory : public DLLFactoryBase +/** This is the highest-level class of the DLLFactory system used to load InspIRCd modules and commands. + * All the dirty mucking around with dl*() is done by DLLManager, all this does it put a pretty shell on + * it and make it nice to use to load modules and core commands. This class is quite specialised for these + * two uses and it may not be useful more generally -- use DLLManager directly for that. + */ +template class CoreExport DLLFactory : public DLLManager { + protected: + /** This typedef represents the init_* function within each module or command. + * The init_module function is the only exported extern "C" declaration + * in any module file. In a cmd_*.cpp file the equivilant is init_command + */ + typedef ReturnType * (initfunctype) (InspIRCd*); + + /** Pointer to the init function. + */ + initfunctype* init_func; + + /** Instance pointer to be passed to init_*() when it is called. + */ + InspIRCd* ServerInstance; + public: - DLLFactory(const char *fname, const char *func_name=0) : DLLFactoryBase(fname,func_name) + /** Default constructor. + * This constructor passes its paramerers down through DLLFactoryBase and then DLLManager + * to load the module, then calls the factory function to retrieve a pointer to a ModuleFactory + * class. It is then down to the core to call the ModuleFactory::CreateModule() method and + * receive a Module* which it can insert into its module lists. + */ + DLLFactory(InspIRCd* Instance, const char *fname, const char *func_name) + : DLLManager(Instance, fname), init_func(NULL), ServerInstance(Instance) + { + const char* error = LastError(); + + if(!error) + { + if(!GetSymbol((void **)&init_func, func_name)) + { + throw FindSymbolException("Missing " + std::string(func_name) + "() entrypoint!"); + } + } + else + { + throw LoadModuleException(error); + } + } + + ReturnType* CallInit() { - if (factory_func) - factory = (T*)factory_func(); + if(init_func) + { + return init_func(ServerInstance); + } else - factory = 0; + { + return NULL; + } } + /** The destructor deletes the ModuleFactory pointer. + */ ~DLLFactory() { - delete factory; } - - T *factory; }; - - - - - #endif