3 #ifndef ALIHLTCOMPONENTHANDLER_H
4 #define ALIHLTCOMPONENTHANDLER_H
5 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
6 * See cxx source for full Copyright notice */
8 /** @file AliHLTComponentHandler.h
9 @author Matthias Richter, Timm Steinbeck
11 @brief Global handling of HLT processing components
12 @note The handler is part of the interface and both used in the
13 Online (PubSub) and Offline (AliRoot) context.
19 #include "AliHLTDataTypes.h"
20 #include "AliHLTLogging.h"
22 class AliHLTComponent;
23 struct AliHLTComponentEnvironment;
24 struct AliHLTComponentDataType;
27 * @class AliHLTComponentHandler
28 * The component handler controls all the processing components available in
29 * the system. It also controls the component shared libraries.
30 * @ingroup alihlt_component
32 class AliHLTComponentHandler : public AliHLTLogging {
34 /** standard constructor */
35 AliHLTComponentHandler();
37 AliHLTComponentHandler(AliHLTComponentEnvironment* pEnv);
39 virtual ~AliHLTComponentHandler();
42 * Set the environment for the HLT framework.
43 * The environment mainly consists of function pointers for the integration
44 * of the HLT framework into a system like the PubSub online system or
45 * AliRoot offline system.
46 * @param pEnv pointer to @ref AliHLTComponentEnvironment structure
49 void SetEnvironment(AliHLTComponentEnvironment* pEnv);
52 * Load a component shared library.
53 * The component library needs to be loaded from the ComponentHanler in order
54 * to automatically register all components in the library.
55 * Registration is done by passing a sample object of the component to the
56 * handler. The object has to be valid during the whole runtime and should
57 * thus be a global object which is ONLY used for the purpose of registration.
58 * This also ensures automatically registration at library load time.
59 * @param libraryPath const char string containing the library name/path
60 * @return 0 if succeeded, neg. error code if failed
62 int LoadLibrary( const char* libraryPath );
65 * Find a symbol in a dynamically loaded library.
66 * @param library library
67 * @param symbol the symbol to find
68 * @return void pointer to function
70 void* FindSymbol(const char* library, const char* symbol);
73 * Unload a component shared library.
74 * All components will be de-registered when the last instance of the
75 * library was unloaded.
76 * @param libraryPath library name as specified to @ref LoadLibrary
77 * @return 0 if succeeded, neg. error code if failed
79 int UnloadLibrary( const char* libraryPath );
82 * Schedule a component for registration.
83 * Full registration will be done after successfull loading of the shared
85 * @param pSample a sample object of the component
86 * @return neg. error code if failed
88 int ScheduleRegister(AliHLTComponent* pSample );
91 * Register a component.
92 * Registration is done by passing a sample object of the component to the
93 * handler. The object has to be valid during the whole runtime and should
94 * thus be a global object which is ONLY used for the purpose of registration.
95 * @param pSample a sample object of the component
96 * @return neg. error code if failed
98 int RegisterComponent(AliHLTComponent* pSample );
101 * Registers all scheduled components.
103 int RegisterScheduledComponents();
106 * Deregister a component.
107 * @param componentID ID of the component
108 * @return neg. error code if failed
110 int DeregisterComponent( const char* componentID );
113 * Add standard components
114 * The standard components are part of the libHLTbase library and
115 * need therefore a special handling.
117 int AddStandardComponents();
121 int DeleteStandardComponents();
124 * Find the ID of a component with the given output data.
125 * @param dtype data type descriptor
126 * @param prevType can be used to iterate if there are multiple components
127 * with the same output data type.
128 * @return component id
130 //const char* FindComponentType( AliHLTComponentDataType dtype,
131 // const char* prevType = NULL )
135 * Create a component of the given name (ID).
136 * The method tries to find a registerd component of id \em componentID and
137 * calls the \em Spawn method of the template component. After successful
138 * creation of a new object, the Init method is called in order to initialize
139 * the environment and the component arguments. <br>
140 * The environment is the same for all components, but each component can
141 * have an additional private parameter \em pEnvParam.<br>
142 * The component arguments consist of an array of strings and the array size
143 * in the usual manner of the main() function.
144 * @param componentID ID of the component to create
145 * @param pEnvParam environment parameter for the component
146 * @param argc number of arguments in argv
147 * @param argv argument array like in main()
148 * @param component reference to receive the create component instance
149 * @return component pointer in component, neg. error code if failed
151 int CreateComponent( const char* componentID, void* pEnvParam,
152 int argc, const char** argv, AliHLTComponent*& component );
155 * Create a component of the given name (ID).
156 * Introduced for backward compatibility.
157 * @param componentID ID of the component to create
158 * @param pEnvParam environment parameter for the component
159 * @param component reference to receive the create component instance
160 * @return component pointer in component, neg. error code if failed
162 int CreateComponent( const char* componentID, void* pEnvParam,
163 AliHLTComponent*& component )
165 return CreateComponent( componentID, pEnvParam, 0, NULL, component );
169 * Print registered components to stdout.
175 * Announce version and compilation info of the base library.
177 int AnnounceVersion();
184 * @param componentID ID of the component to find
185 * @return index, neg. error code if failed
187 int FindComponentIndex(const char* componentID);
191 * @param componentID ID of the component to find
194 AliHLTComponent* FindComponent(const char* componentID);
197 * Insert component to the list
198 * @param pSample sample object of the component
199 * @return neg. error code if failed
201 int InsertComponent(AliHLTComponent* pSample);
204 * Close all libraries.
205 * @return neg. error code if failed
207 int UnloadLibraries();
210 * Compount descriptor for component libraries
212 struct AliHLTLibHandle {
213 AliHLTLibHandle() : handle(NULL), name(NULL) {}
215 void* handle; //! transient
216 /** name of the library, casted to TString* before use */
217 void* name; //! transient
221 * Find a specific library among the loaded libraries.
222 * @param library library name/path
223 * @return pointer to AliHLTLibHandle
225 AliHLTLibHandle* FindLibrary(const char* library);
228 * Unload a component shared library.
229 * All components will be de-registered when the last instance of the
230 * library was unloaded.
231 * @param handle handle to the library to unload
232 * @return 0 if succeeded, neg. error code if failed
234 int UnloadLibrary(AliHLTComponentHandler::AliHLTLibHandle &handle);
236 /** list of registered components */
237 vector<AliHLTComponent*> fComponentList; // see above
238 /** list of scheduled components */
239 vector<AliHLTComponent*> fScheduleList; // see above
240 /** list of libraries */
241 vector<AliHLTLibHandle> fLibraryList; // see above
242 /** running environment for the component */
243 AliHLTComponentEnvironment fEnvironment; // see above
244 /** list of standard components */
245 vector<AliHLTComponent*> fStandardList; // see above
247 ClassDef(AliHLTComponentHandler, 0);