1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd: (C) 2002-2008 InspIRCd Development Team
6 * See: http://www.inspircd.org/wiki/index.php/Credits
8 * This program is free but copyrighted software; see
9 * the file COPYING for details.
11 * ---------------------------------------------------
17 /** The DLLManager class is able to load a module file by filename,
18 * and locate its init_module symbol.
20 class CoreExport DLLManager
24 /** The last error string, or NULL
29 /** This constructor loads the module using dlopen()
30 * @param ServerInstance The creator class of this object
31 * @param fname The filename to load. This should be within
34 DLLManager(InspIRCd* ServerInstance, const char *fname);
35 virtual ~DLLManager();
37 /** Get a symbol using dynamic linking.
38 * @param v A function pointer, pointing at an init_module function
39 * @param sym_name The symbol name to find, usually "init_module"
40 * @return true if the symbol can be found, also the symbol will be put into v.
42 bool GetSymbol(void **v, const char *sym_name);
44 /** Get the last error from dlopen() or dlsym().
45 * @return The last error string, or NULL if no error has occured.
47 const char* LastError()
52 /** The module handle.
53 * This is OS dependent, on POSIX platforms it is a pointer to a function
54 * pointer (yes, really!) and on windows it is a library handle.
59 class CoreExport LoadModuleException : public CoreException
62 /** This constructor can be used to specify an error message before throwing.
64 LoadModuleException(const std::string &message)
65 : CoreException(message, "the core")
69 /** This destructor solves world hunger, cancels the world debt, and causes the world to end.
70 * Actually no, it does nothing. Never mind.
73 virtual ~LoadModuleException() throw() {};
76 class CoreExport FindSymbolException : public CoreException
79 /** This constructor can be used to specify an error message before throwing.
81 FindSymbolException(const std::string &message)
82 : CoreException(message, "the core")
86 /** This destructor solves world hunger, cancels the world debt, and causes the world to end.
87 * Actually no, it does nothing. Never mind.
90 virtual ~FindSymbolException() throw() {};
93 /** This is the highest-level class of the DLLFactory system used to load InspIRCd modules and commands.
94 * All the dirty mucking around with dl*() is done by DLLManager, all this does it put a pretty shell on
95 * it and make it nice to use to load modules and core commands. This class is quite specialised for these
96 * two uses and it may not be useful more generally -- use DLLManager directly for that.
98 template <typename ReturnType> class CoreExport DLLFactory : public DLLManager
101 /** This typedef represents the init_* function within each module or command.
102 * The init_module function is the only exported extern "C" declaration
103 * in any module file. In a cmd_*.cpp file the equivilant is init_command
105 typedef ReturnType * (initfunctype) (InspIRCd*);
107 /** Pointer to the init function.
109 initfunctype* init_func;
111 /** Instance pointer to be passed to init_*() when it is called.
113 InspIRCd* ServerInstance;
116 /** Default constructor.
117 * This constructor passes its paramerers down through DLLFactoryBase and then DLLManager
118 * to load the module, then calls the factory function to retrieve a pointer to a ModuleFactory
119 * class. It is then down to the core to call the ModuleFactory::CreateModule() method and
120 * receive a Module* which it can insert into its module lists.
122 DLLFactory(InspIRCd* Instance, const char *fname, const char *func_name)
123 : DLLManager(Instance, fname), init_func(NULL), ServerInstance(Instance)
125 const char* error = LastError();
129 if(!GetSymbol((void **)&init_func, func_name))
131 throw FindSymbolException("Missing " + std::string(func_name) + "() entrypoint!");
136 throw LoadModuleException(error);
140 /** Calls the 'init_module' C exported function within a module, which
141 * returns a pointer to a Module derived object.
143 ReturnType* CallInit()
147 return init_func(ServerInstance);
155 /** The destructor deletes the ModuleFactory pointer.