1 / 17

C++ Toolbox for Efficient TANGO Device Implementation

The ADTB Library by N. Leclercq & J. Malik offers a threading support system, message handling features, mutex classes, and bit fields support for harmonized maintenance of TANGO device implementations. The library provides code factorization to prevent reinventing the wheel and aggregation of tools for recurrent needs.

cybil
Download Presentation

C++ Toolbox for Efficient TANGO Device Implementation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The ADTB Library N.Leclercq – J.Malik – INF/ICA

  2. ADTB – What is this? • C++ toolbox for TANGO device impl. • dependencies: Tango.lib & omnithread.lib • but… should be independent • Aggregation of software tools • recurrent needs >> ! reinvent the wheel • code factorization >> maintenance • impl. harmonization >> maintenance

  3. ADTB – Features • Threading support • La classe adtb::DeviceTask • a task = a thread + messageQ • consumes messages [passive approach] • periodic activity and/or stimulated by “external” messages • interface… • go (size_t tmo_ms) [sync.] [!!! no auto start !!!] • post (Message * m) [async.] • wait_msg_handled (Message * m, size_t tmo_ms) [sync.] • abort (bool join, size_t tmo_ms) [sync.] [!!! self delete !!!]

  4. ADTB – Features • Threading support • The adtb::Message class • inherits from adtb::SharedObject • a message can be posted to several tasks • reference counter (release - not delete) • message has a type [user defined] • can carry any kind of data • user : msg->attach_data(any_data_type[& ou *]) • task : ExpectedDataType* d = msg->dettach_data();…; delete msg; • hidden generic container + template method • runtime error on data extraction [!!! programming error !!!] • dynamic_cast >> std::bad_cast

  5. ADTB – Feature • Threading support • go back to adtb::DeviceTask • message handling : predefined messages class MyTask : public adtb::DeviceTask { protected: ... void handle_message (const adtb::Message& _msg) throw (Tango::DevFailed) { //- !!! you may be under critical section !!! switch ( _msg.type() ) { //- THREAD_INIT ---------------------- case adtb::THREAD_INIT: //- "initialization" code goes here break; //- THREAD_EXIT ---------------------- case adtb::THREAD_EXIT: //- "release" code goes here break;

  6. ADTB – Feature • Threading support • go back to adtb::DeviceTask • message handling : periodic & user defined messages //- THREAD_PERIODIC ------------------ case adtb::THREAD_PERIODIC: //- task's periodic job break; //- USER_DEFINED_MSG ----------------- case kMY_DOUBLE_MSG: //- get msg data... double * double_value = 0; _msg.dettach_data(double_value); //- do somthing with double_value then... delete double_value; break; } // - switch } // - handle_message }; // class MyTask

  7. ADTB – Feature • Threading support • The adtb::DeviceMutex class • omni_mutex interface + … • int try_lock (DeviceMutexStatus & status); • return 0 : ok, locked (status = MTX_LOCKED) • return -1 : ko, could not be locked (status = MTX_BUSY or MTX_ERROR) • may be helpful to avoid deadlock • The adtb::DummyMutex class • empty/do nothing impl. of the DeviceMutex interface • optional ‘ThreadSafety’ [locking overhead] • template <typename LOCK> class MyClass • exemple : galil::HwIO [1 shared connection + 1 private] • The adtb::DeviceMutexLock<LOCK> class • omni_mutex_lock interface • default template arg. = DeviceMutex • The adtb::DeviceCondition class • same as omni_condition but… • maintains «signaled» state [alarm clock rings before sleeping syndrom] • required for DeviceTask impl. • may not be adapted to any situation >> an other class required?

  8. ADTB – Features • Bit fields support [adtb::BitsStream] • Application fields… • management of composite data structures in which the data is coded on 1 to 32 bits (*) • mostly hardware I/O • Principle… • using the provided “user description”, the BitsStream extracts each field, does some byte-swapping (if required) then stores the value into the “explicitly associated” C++ data type • Example… (*) could support >32 bits fields

  9. ADTB – Features • adtb::BitsStream : struct description BEGIN_BITS_RECORD(BR_MotorState) MEMBER(moving,1, bool); IGNORE_MEMBER(reserved_1, 1, bool); MEMBER(forward_ls, 1, bool); MEMBER(backward_ls, 1, bool); IGNORE_MEMBER(reserved_2, 4, unsigned char); MEMBER(error_code, 8, unsigned char); END_BITS_RECORD(BR_MotorState)

  10. ADTB – Features • adtb::BitsStream : data extractor • discribes how to extract the data • BEGIN_BITS_RECORD_EXTRACTOR(BR_MotorState) • EXTRACT_MEMBER(moving); • SKIP_BITS(1); • EXTRACT_MEMBER(forward_ls); • EXTRACT_MEMBER(backward_ls); • SKIP_BITS(4); • EXTRACT_MEMBER(error_code); • END_BITS_RECORD_EXTRACTOR(BR_MotorState)

  11. ADTB – Features • adtb::BitsStream : logging… • useful for debugging… BEGIN_BITS_RECORD_DUMP(BR_MotorState) DUMP_MEMBER(moving); DUMP_SKIP_BITS(1); DUMP_MEMBER(forward_ls); DUMP_MEMBER(backward_ls); DUMP_SKIP_BITS(4); DUMP_MEMBER(error_code); END_BITS_RECORD_DUMP(BR_MotorState)

  12. ADTB – Features • adtb::BitsStream :class specialization… • providing semantically powerful interface • note the () operator class MotorState : public BR_MotorState { public: inline bool any_limit_switch_detected () { return this->forward_ls() || this->backward_ls(); } }

  13. ADTB – Features • Data buffers… (generic containers) • adtb::DataBuffer • template: generic container • adtb::SharedBuffer • : public Buffer<T>, private SharedObject • adtb::CircularBuffer • data historic [ex : post mortem] • const adtb::Buffer<T> & ordered_data (void) const

  14. ADTB – Features • Other classes… • adtb::ThreadSafeDeviceProxy • should be provided by the Tango core lib! • adtb::ThreadSafeDeviceProxyHelper • thread safe version of DeviceProxyHelper • adtb::XString • bidirectional numeric to string conversion • adtb::PluginManager & related classes • provided the basics for plugin support • ultimate hardware abstraction behind a Tango dev. Interface • ex.: SOLEIL image grabber

  15. ADTB – Features • Other classes… • adtb::Work & Workers (in progress – 90% done) • data stream model impl. • each node is a Worker having a Work to do • uses the adtb::DeviceTask from data propagation

  16. ADTB – Features • Other small stuffs… • Inline • inline control: release but not for debug • Developer logging • DEBUG_TRACE • DEBUG_LOG • generates logs in DEBUG mode only

  17. ADTB – Near Future • Client socket class • platform abstraction • Criteria & Filter • generic [composite] filters for data treatment

More Related