+/* +------------------------------------+
+ * | 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 T> 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 <typename ReturnType> 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
projects / user / henk / code / inspircd.git / blobdiff