Author: tgoettlicher Date: Wed May 16 16:32:15 2007 New Revision: 5559 URL: http://svn.opensuse.org/viewcvs/zypp?rev=5559&view=rev Log: first steps in using plugins Added: branches/tmp/tgoettlicher/ branches/tmp/tgoettlicher/updater-gnome-kde/ branches/tmp/tgoettlicher/updater-gnome-kde/Makefile branches/tmp/tgoettlicher/updater-gnome-kde/PlugInFun.cc branches/tmp/tgoettlicher/updater-gnome-kde/PlugInHappy.cc branches/tmp/tgoettlicher/updater-gnome-kde/dll.cc branches/tmp/tgoettlicher/updater-gnome-kde/dll.h branches/tmp/tgoettlicher/updater-gnome-kde/plugin.cc branches/tmp/tgoettlicher/updater-gnome-kde/plugin.h branches/tmp/tgoettlicher/updater-gnome-kde/plugtest.cc Added: branches/tmp/tgoettlicher/updater-gnome-kde/Makefile URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/Makefile?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/Makefile (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/Makefile Wed May 16 16:32:15 2007 @@ -0,0 +1,40 @@ + +# The flags needed to compile all +CXXFLAGS = -fPIC -frtti -O + +# we need to link in the dll handling library + +LDLIBS = -ldl + + +all : plugtest PlugInFun.so PlugInHappy.so + +# the main executable has to be linked with the -rdynamic flag +# so the plug in libraries can call inherited methods and +# access vtables in the main executable. + +plugtest : plugtest.o dll.o plugin.o + $(CXX) -rdynamic $^ -o $@ $(LDLIBS) + +# link the shared libraries with the -shared flag. + +PlugInFun.so : PlugInFun.o + $(CXX) $(CXXFLAGS) -shared $^ -o $@ + +PlugInHappy.so : PlugInHappy.o + $(CXX) $(CXXFLAGS) -shared $^ -o $@ + + +clean : + -rm *.o + +realclean : clean + -rm plugtest *.so + + + + + + + + Added: branches/tmp/tgoettlicher/updater-gnome-kde/PlugInFun.cc URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/PlugInFun.cc?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/PlugInFun.cc (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/PlugInFun.cc Wed May 16 16:32:15 2007 @@ -0,0 +1,65 @@ +#include <typeinfo> +#include <iostream> +#include "plugin.h" + +// Class PlugInFun inherits from PlugIn +// and shows the world when one is created/destroyed +// and supplies a Show() method that announces its name + + +class PlugInFun : public PlugIn +{ + public: + PlugInFun() + { + cout << "PlugInFun created" << endl; + } + + virtual ~PlugInFun() + { + cout << "PlugInFun destroyed" << endl; + } + + virtual void Show() + { + cout << "I am a Fun PlugIn" << endl; + } +}; + +// +// The PlugInFunFactory class inherits from PlugInFactory +// and creates a PlugInFun object when requested. +// + + +class PlugInFunFactory : public PlugInFactory +{ + public: + PlugInFunFactory() + { + } + + ~PlugInFunFactory() + { + } + + virtual PlugIn * CreatePlugIn() + { + return new PlugInFun; + } + +}; + + +// +// The "C" linkage factory0() function creates the PlugInFunFactory +// class for this library +// + + +extern "C" void * factory0( void ) +{ + return new PlugInFunFactory; +} + + Added: branches/tmp/tgoettlicher/updater-gnome-kde/PlugInHappy.cc URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/PlugInHappy.cc?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/PlugInHappy.cc (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/PlugInHappy.cc Wed May 16 16:32:15 2007 @@ -0,0 +1,64 @@ +#include <typeinfo> +#include <iostream> +#include <string> +#include "plugin.h" + + +// Class PlugInHappy inherits from PlugIn +// and shows the world when one is created/destroyed +// and supplies a Show() method that announces its name + +class PlugInHappy : public PlugIn +{ + public: + PlugInHappy() + { + cout << "PlugInHappy() Created" << endl; + } + + virtual ~PlugInHappy() + { + cout << "PlugInHappy() destroyed" << endl; + } + + virtual void Show() + { + cout << "I am a New Happy PlugIn" << endl; + } +}; + + +// +// The PlugInHappyFactory class inherits from PlugInFactory +// and creates a PlugInHappy object when requested. +// + +class PlugInHappyFactory : public PlugInFactory +{ + public: + PlugInHappyFactory() + { + } + + ~PlugInHappyFactory() + { + } + + virtual PlugIn * CreatePlugIn() + { + return new PlugInHappy; + } + +}; + + +// +// The "C" linkage factory0() function creates the PlugInHappyFactory +// class for this library +// + +extern "C" void * factory0( void ) +{ + return new PlugInHappyFactory; +} + Added: branches/tmp/tgoettlicher/updater-gnome-kde/dll.cc URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/dll.cc?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/dll.cc (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/dll.cc Wed May 16 16:32:15 2007 @@ -0,0 +1,73 @@ +#include <typeinfo> +#include <iostream> +#include <string> +#include +#include "dll.h" + + + +DLLManager::DLLManager( const char *fname ) +{ + // Try to open the library now and get any error message. + + h=dlopen( fname, RTLD_NOW ); + err=dlerror(); +} + +DLLManager::~DLLManager() +{ + // close the library if it isn't null + if( h!=0 ) + dlclose(h); +} + + +bool DLLManager::GetSymbol( + void **v, + const char *sym_name + ) +{ + // try extract a symbol from the library + // get any error message is there is any + + if( h!=0 ) + { + *v = dlsym( h, sym_name ); + err=dlerror(); + if( err==0 ) + return true; + else + return false; + } + else + { + return false; + } + +} + + +DLLFactoryBase::DLLFactoryBase( + const char *fname, +// const char *factory=0 + const char *factory + ) : DLLManager(fname) +{ + // try get the factory function if there is no error yet + + factory_func=0; + + if( LastError()==0 ) + { + GetSymbol( (void **)&factory_func, factory ? factory : "factory0" ); + } + +} + + +DLLFactoryBase::~DLLFactoryBase() +{ +} + + + Added: branches/tmp/tgoettlicher/updater-gnome-kde/dll.h URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/dll.h?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/dll.h (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/dll.h Wed May 16 16:32:15 2007 @@ -0,0 +1,115 @@ + +#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 +{ + public: + DLLManager( const char *fname ); + virtual ~DLLManager(); + + + bool GetSymbol( void **, const char *sym_name ); + + const char *LastError() + { + return err; + } + + protected: + 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 +{ + public: + DLLFactoryBase( + const char *fname, + const char *factory=0 + ); + + virtual ~DLLFactoryBase(); + + void * (*factory_func)(void); +}; + + +// +// 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 +{ + public: + DLLFactory( + const char *fname, + const char *func_name=0 + ) : DLLFactoryBase( fname, func_name ) + { + if( factory_func ) + factory = (T *)factory_func(); + else + factory = 0; + } + + ~DLLFactory() + { + delete factory; + } + + T *factory; +}; + + + + + + +#endif Added: branches/tmp/tgoettlicher/updater-gnome-kde/plugin.cc URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/plugin.cc?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/plugin.cc (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/plugin.cc Wed May 16 16:32:15 2007 @@ -0,0 +1,19 @@ +#include <typeinfo> +#include <iostream> +#include "plugin.h" + +// +// Announce to the world that the PlugIn base +// class has been created or destroyed +// + +PlugIn::PlugIn() +{ + cout << "PlugIn Created" << endl; +} + +PlugIn::~PlugIn() +{ + cout << "PlugIn Destroyed" << endl; +} + Added: branches/tmp/tgoettlicher/updater-gnome-kde/plugin.h URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/plugin.h?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/plugin.h (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/plugin.h Wed May 16 16:32:15 2007 @@ -0,0 +1,65 @@ +#ifndef __PLUGIN_H +#define __PLUGIN_H + + +#include "dll.h" + +using namespace std; + + +// +// PlugIn is an abstract class. +// +// This is an example plug in. This plug in only has one method, Show(), +// which we will use to show its name. +// +// + +class PlugIn +{ + public: + PlugIn(); + + virtual ~PlugIn(); + + virtual void Show() = 0; +}; + + +// +// The is an example factory for plug ins. +// +// This example factory only announces when it is created/destroyed and +// has the single abstract method CreatePlugIn() which returns a type +// of plug in. +// +// In the real world, you may have multiple different classes in each +// shared library that are made to work together. All these classes +// must be created by the Factory class. +// +// You may find it useful to have the objects that you create with +// the factory class be given a pointer to the factory class so +// they can create their own objects that they need, using the same +// factory class. Compiler support of covariant return types is +// real useful here. +// + + +class PlugInFactory +{ + public: + PlugInFactory() + { + cout << "PlugInFactory Created" << endl; + } + + virtual ~PlugInFactory() + { + cout << "PlugInFactory Destroy" << endl; + } + + virtual PlugIn * CreatePlugIn() = 0; + +}; + +#endif Added: branches/tmp/tgoettlicher/updater-gnome-kde/plugtest.cc URL: http://svn.opensuse.org/viewcvs/zypp/branches/tmp/tgoettlicher/updater-gnome-kde/plugtest.cc?rev=5559&view=auto ============================================================================== --- branches/tmp/tgoettlicher/updater-gnome-kde/plugtest.cc (added) +++ branches/tmp/tgoettlicher/updater-gnome-kde/plugtest.cc Wed May 16 16:32:15 2007 @@ -0,0 +1,71 @@ +#include <typeinfo> +#include <iostream> +#include <string> +#include "dll.h" +#include "plugin.h" + +using namespace std; + +main() +{ + + // Ask the user for the name of the DLL + + string fname, fname2; + cout << "Type in a full pathname of a dll:"; + cin >> fname; + cin >> fname2; + + + // show it + + cout << endl << "Opening '" << fname << "'" << endl; + + // Now create a DLLFactory for our PlugInFactory attached + // to the requested file + + DLLFactory<PlugInFactory> dll( fname.c_str() ); + DLLFactory<PlugInFactory> dll2( fname2.c_str() ); + + // + // If it worked we should have dll.factory pointing + // to a subclass of PlugInFactory + // + + if( dll.factory ) + { + // + // yes, we have a factory. Ask the factory to create a + // PlugIn object for us. + // + + PlugIn *c=dll.factory->CreatePlugIn(); + PlugIn *d=dll2.factory->CreatePlugIn(); + + // tell it to show itself + + c->Show(); + d->Show(); + + // show the C++ RTTI typeid name to the user + + cout << "type name = " << typeid(*c).name() << endl; + + // kill the plug in. + + delete c; + } + else + { + cout << "Error opening dll!" << endl; + + // show the error message if any + + if( dll.LastError() ) + { + cout << "DLL Error: " << dll.LastError() << endl; + } + + } + +} -- To unsubscribe, e-mail: zypp-commit+unsubscribe@opensuse.org For additional commands, e-mail: zypp-commit+help@opensuse.org