// @(#) $Id$ #ifndef ALIHLTDATABUFFER_H #define ALIHLTDATABUFFER_H /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * * See cxx source for full Copyright notice */ /** @file AliHLTDataBuffer.h @author Matthias Richter @date @brief Handling of Data Buffers for HLT components. @note The class is used in Offline (AliRoot) context */ // see below for class documentation // or // refer to README to build package // or // visit http://web.ift.uib.no/~kjeks/doc/alice-hlt #include #include "AliHLTLogging.h" #include "AliHLTDataTypes.h" #include "TObject.h" class AliHLTComponent; class AliHLTConsumerDescriptor; /** * @class AliHLTDataBuffer * @brief Handling of data buffers for the HLT. * * The class provides handling of data buffers for HLT tasks. Each task gets * its own Data Buffer instance. The buffer is grouped into different data * segments according to the output of the component.
* The Data Buffer keeps control over the data requests of the 'child' * components. Each component can subscribe to a certain segment of the data * buffer. It's state is then changed from 'reserved' to 'active'. After the * data processing, the component has to release the segment and it's state is * set to 'processed'. If all components have requested and released their data, * the Raw Buffer is released and pushed back in the list of available buffers. * * @note This class is only used for the @ref alihlt_system. * * @ingroup alihlt_system */ class AliHLTDataBuffer : public TObject, public AliHLTLogging { public: ////////////////////////////////////////////////////////////////////////////// // constructors and destructors /* standard constructor */ AliHLTDataBuffer(); /** destructor */ virtual ~AliHLTDataBuffer(); ////////////////////////////////////////////////////////////////////////////// // initialization /** * Add component to the list of consumers * @param pConsumer - a consumer of type AliHLTComponent */ int SetConsumer(AliHLTComponent* pConsumer); ////////////////////////////////////////////////////////////////////////////// // component to component communication /** * Determine the number of matching data blocks for the component and a * consumer component.
* The first approach will support only one output data type for processing * components. * @param pConsumer the component which subscribes to the buffer * @param tgtList (optional) the list to receive the data types * @return: number of data blocks which match the input data types * of the consumer, neg. error code if failed
* -EINVAL invalid parameter
*/ int FindMatchingDataBlocks(const AliHLTComponent* pConsumer, vector* tgtList=NULL); /** * Subscribe to a segment of the data buffer. * The function prepares the block descriptor for subsequent use with the * AliHLTComponent::ProcessEvent method, the method can prepare several block * descriptors up to the array size specified by iArraySize. The return value * is independent from the array size the number of block descriptors which * would have been prepared if there was enough space in the array
* The method is used by the consumer component. * @param pConsumer the component which subscribes to the buffer * @param arrayBlockDesc pointer to block descriptor to be filled * @param iArraySize size of the block descriptor array * @return: number of matching data blocks, neg. error code if failed
* -EACCESS the consumer state can't be changed (activated) * -EBADF unresolved data segments
* -ENOENT consumer component not found
* -ENODATA data buffer does not have raw data
* -EINVAL invalid parameter
*/ int Subscribe(const AliHLTComponent* pConsumer, AliHLTComponentBlockData* arrayBlockDesc, int iArraySize); /** * Release an instance of the data buffer. * Resets the variables of the block descriptor. * If all buffer segments are released, the Data Buffer is reseted * and the Raw Buffer released.
* The method is used by the consumer component. * @param pBlockDesc descriptor of the data segment * @param pConsumer the component which subscribes to the buffer * @return: >0 if success, negative error code if failed
* -EACCESS the consumer state can not be changed (de-activated) * -ENOENT consumer has not subscribed to the buffer
* -EINVAL invalid parameter
*/ int Release(AliHLTComponentBlockData* pBlockDesc, const AliHLTComponent* pConsumer); /** * Get a target buffer of minimum size iMinSize. * The method is used by the component which owns the Data Buffer to * allocate a buffer for the data it is going to produce. * @param iMinSize minumum size of the requested buffer * @return: pointer to target buffer if */ AliHLTUInt8_t* GetTargetBuffer(int iMinSize); /** * Set the segments for the data buffer. * This is usually done after the component has written the data to the buffer, * which was requested by the @ref GetTargetBuffer method. The component might * produce different types of data, for each type a segment has to be defined * which describes the data inside the buffer.
* The @ref AliHLTComponentBlockData segment descriptor comes directly from * the @ref AliHLTComponent::ProcessEvent method. * @param pTgt the target buffer which the segments refer to * @param arraySegments the output block descriptors of the component * @param iSize size of the array */ int SetSegments(AliHLTUInt8_t* pTgt, AliHLTComponentBlockData* arraySegments, int iSize); /** * Check if the data buffer is empty. * @return 1 if empty, 0 if not */ int IsEmpty(); /** * Get the total and maximum size of the buffer. * Lets see if this is needed later */ //int GetTotalSize(); /** * Get the number of segments * @return number of segments */ int GetNofSegments(); /** * Get the total number of consumers. * This gives the number of consumers regardless of their state. * @return number of consumers */ int GetNofConsumers(); /** * Get the number of consumers which still need to be processed during * the current event. * @return number of consumers */ int GetNofPendingConsumers(); /** * Get the number of consumers currently under processing. * @return number of active consumers */ int GetNofActiveConsumers(); /** * Check if a consumer is already in the list * @param pConsumer pointer to consumer component * @param bAllLists search in all lists if 1 * search only in fConsumer list if 0 * @return 1 if found, 0 if not */ int FindConsumer(AliHLTComponent* pConsumer, int bAllLists=1); /** * Public method to reset the buffer. * Eventually with some additional checks. In normal operation, * an external reset should not be necessary. */ int Reset(); /** * @class AliHLTDataSegment * @brief Descriptor of a data segment within the buffer. */ class AliHLTDataSegment { friend class AliHLTDataBuffer; friend class AliHLTConsumerDescriptor; public: AliHLTDataSegment() : fDataType(), fSegmentOffset(0), fSegmentSize(0), fSpecification(0) { memset(&fDataType, 0, sizeof(AliHLTComponentDataType)); } AliHLTDataSegment(AliHLTUInt32_t offset, AliHLTUInt32_t size) : fDataType(), fSegmentOffset(offset), fSegmentSize(size), fSpecification(0) { memset(&fDataType, 0, sizeof(AliHLTComponentDataType)); } private: /** the data type of this segment */ AliHLTComponentDataType fDataType; // see above /** offset in byte within the data buffer */ AliHLTUInt32_t fSegmentOffset; // see above /** size of the actual content */ AliHLTUInt32_t fSegmentSize; // see above /** data specification */ AliHLTUInt32_t fSpecification; // see above }; /** * @class AliHLTRawBuffer * @brief Descriptor of the raw data buffer which can host several segments. */ class AliHLTRawBuffer { friend class AliHLTDataBuffer; public: /** standard constructor */ AliHLTRawBuffer() : fSize(0), fTotalSize(0), fPtr(NULL) {} /** not a valid copy constructor, defined according to effective C++ style */ AliHLTRawBuffer(const AliHLTRawBuffer&) : fSize(0), fTotalSize(0), fPtr(NULL) {} /** not a valid assignment op, but defined according to effective C++ style */ AliHLTRawBuffer& operator=(const AliHLTRawBuffer&) {return *this;} /** standard destructor */ virtual ~AliHLTRawBuffer() {} int operator==(void*) const; int operator==(AliHLTUInt8_t* ptr) const {return fPtr==ptr;} int operator<=(void*) const; int operator>(void*) const; int operator-(void*) const; operator void*() const {return fPtr;} operator AliHLTUInt8_t*() const {return fPtr;} private: /** size of the currently occupied partition of the buffer */ AliHLTUInt32_t fSize; // see above /** total size of the buffer, including safety margin */ AliHLTUInt32_t fTotalSize; // see above /** the buffer */ AliHLTUInt8_t* fPtr; //! transient }; private: /** copy constructor prohibited */ AliHLTDataBuffer(const AliHLTDataBuffer&); /** assignment operator prohibited */ AliHLTDataBuffer& operator=(const AliHLTDataBuffer&); /* lets see if this is needed AliHLTDataSegment* FindDataSegment(AliHLTComponentDataType datatype); */ /** * Find those data segments which match the input types of a component. * @param pConsumer the component which subscribes to the buffer * @param tgtList the list to receive the data segment descriptors * @return: number of data blocks which match the input data types * of the consumer, neg. error code if failed
* -EINVAL invalid parameter
*/ int FindMatchingDataSegments(const AliHLTComponent* pConsumer, vector& tgtList); /** * Reset the data buffer. * Removes all consumers back to the @ref fConsumers list, deletes * segments and releases the Raw Buffer. */ int ResetDataBuffer(); ////////////////////////////////////////////////////////////////////////////// // the data description // the data segments within this buffer vector fSegments; // see above // the list of all consumers which are going to subscribe to the buffer vector fConsumers; // see above // the list of all consumers which are currently subscribed to the buffer vector fActiveConsumers; // see above // the list of all consumers which are already released for the current event vector fReleasedConsumers; // see above // the buffer instance AliHLTRawBuffer* fpBuffer; //! transient // flags indicating the state of the buffer AliHLTUInt32_t fFlags; // see above ////////////////////////////////////////////////////////////////////////////// // global buffer handling, internal use only /** * Create a raw buffer of a certain size. * The function tries to find a buffer of the given size (or a bit bigger by a * certain margin @ref fgMargin) from the list of free buffers. * If no buffer is available, a new one is created and added to the buffer handling. * @param size min. size of the requested buffer * @return pointer to raw buffer */ static AliHLTRawBuffer* CreateRawBuffer(AliHLTUInt32_t size); /** * Mark a buffer as free. * After the Data Buffer has finnished using the raw buffer, it is released * and added to the list of available buffers. * @param pBuffer the raw buffer to release * @return >=0 if succeeded, neg. error code if failed */ static int ReleaseRawBuffer(AliHLTRawBuffer* pBuffer); /** * Deletes all the raw buffers. * When the last Data Buffer object is destructed, all raw data buffers are * relesed. */ static int DeleteRawBuffers(); /** * Number of instances of AliHLTDataBuffer. * The statice variable is incremented and decremented in the constructor/ * destructor. All internal data structures are cleaned up when the last * instance is exiting. */ static int fgNofInstances; // see above /** global list of free raw buffers */ static vector fgFreeBuffers; // see above /** global list of currently active raw buffers */ static vector fgActiveBuffers; // see above /** determines the raw buffer size margin at buffer requests */ static AliHLTUInt32_t fgMargin; // see above /** global instance to HLT logging class for static methods */ static AliHLTLogging fgLogging; // see above /** size of the safety pattern */ static const Int_t fgkSafetyPatternSize; // see above /** the safety pattern */ static const char fgkSafetyPattern[]; //!transient ////////////////////////////////////////////////////////////////////////////// // internal helper functions /** * Find the consumer descriptor for a certain component and data type in * a list of consumers.
* Note: There are three lists which contain the consumers in the * different states. * @param pConsumer pointer to consumer component * @param list list where to search for the consumer */ AliHLTConsumerDescriptor* FindConsumer(const AliHLTComponent* pConsumer, vector &list) const; /** * Change the state of a consumer. * The state of a consumer is determined by the list it is strored in, the * method moves a consumer from the source to the target list. * @param pDesc pointer to consumer descriptor * @param srcList list where the consumer is currently to be found * @param tgtList list where to move the consumer */ int ChangeConsumerState(AliHLTConsumerDescriptor* pDesc, vector &srcList, vector &tgtList); /** * Cleanup a consumer list. * Release all allocated data structures. Note: Not the component itself! */ int CleanupConsumerList(); ClassDef(AliHLTDataBuffer, 0) }; #endif // ALIHLTDATABUFFER_H