.. _program_listing_file_falcon_istreamports.hpp:

Program Listing for File istreamports.hpp
=========================================

|exhale_lsh| :ref:`Return to documentation for file <file_falcon_istreamports.hpp>` (``falcon/istreamports.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // ---------------------------------------------------------------------
   // This file is part of falcon-core.
   //
   // Copyright (C) 2015, 2016, 2017 Neuro-Electronics Research Flanders
   //
   // Falcon-server is free software: you can redistribute it and/or modify
   // it under the terms of the GNU General Public License as published by
   // the Free Software Foundation, either version 3 of the License, or
   // (at your option) any later version.
   //
   // Falcon-server is distributed in the hope that it will be useful,
   // but WITHOUT ANY WARRANTY; without even the implied warranty of
   // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   // GNU General Public License for more details.
   //
   // You should have received a copy of the GNU General Public License
   // along with falcon-core. If not, see <http://www.gnu.org/licenses/>.
   // ---------------------------------------------------------------------
   
   #pragma once
   
   #include <memory>
   #include <set>
   #include <string>
   #include <vector>
   
   #include "connections.hpp"
   #include "idata.hpp"
   #include "portpolicy.hpp"
   #include "streaminfo.hpp"
   
   #include "yaml-cpp/yaml.h"
   
   class IPortOut;
   class ISlotOut;
   class IPortIn;
   class ISlotIn;
   class IProcessor;
   
   class ISlotOut {
     friend class ISlotIn;
     template <typename DATATYPE> friend class SlotIn;
     friend class IPortOut;
   
    public:
     ISlotOut(IPortOut *parent, const SlotAddress &address)
         : ring_batch_(1), buffer_size_(-1), parent_(parent), address_(address) {}
   
     virtual ~ISlotOut(){}
   
     const SlotAddress &address() const { return address_; }
     IPortOut *parent() { return parent_; }
     bool connected() const { return downstream_slots_.size() > 0; }
     int nconnected() const { return downstream_slots_.size(); }
     virtual IStreamInfo &streaminfo() = 0;
     int buffer_size() const { return buffer_size_; }
   
    protected:
     // called by IPortOut
     void Connect(ISlotIn *downstream);
   
     // called by SlotIn
     int64_t WaitFor(int64_t sequence) const {
       return barrier_->WaitFor(sequence);
     }
     int64_t WaitFor(int64_t sequence, int64_t time_out) const {
       return barrier_->WaitFor(sequence, time_out);
     }
   
     virtual typename AnyType::Data *DataAt(int64_t sequence) const = 0;
     std::vector<RingSequence *> gating_sequences();
   
    protected:
     RingBatch ring_batch_;
     bool has_publishable_data_ = false;
   
     // need to go through base class, since we don't know
     // the exact datatype of downstream slots
     std::set<ISlotIn *> downstream_slots_;
   
     std::unique_ptr<RingBarrier> barrier_ = nullptr;
     int buffer_size_;
   
     IPortOut *parent_;   // observing pointer
     SlotAddress address_;
   };
   
   class IPortOut {
     friend class ProcessorEngine;
     friend class IProcessor;
   
    public:
     IPortOut(IProcessor *parent, const PortAddress &address, PortOutPolicy policy)
         : parent_(parent), address_(address), policy_(policy) {}
   
     virtual ~IPortOut(){}
     const PortAddress &address() const { return address_; }
     const PortOutPolicy &policy() const { return policy_; }
     IProcessor *parent() { return parent_; }
   
     virtual std::string datatype() const = 0;
     virtual ISlotOut *slot(std::size_t index) = 0;
     virtual SlotType number_of_slots() const = 0;
     virtual const typename AnyType::Capabilities &capabilities() const = 0;
   
     YAML::Node ExportYAML() const;
     std::string name() const { return address_.port(); }
   
    protected:
     // called by StreamOutConnector
     virtual void Connect(int slot, ISlotIn *downstream) = 0;
     virtual int ReserveSlot(int slot) = 0;
     virtual void CreateRingBuffers() = 0;
     virtual void UnlockSlots() = 0;
     virtual void PrepareProcessing() = 0;
     virtual void NewSlot(int n = 1) = 0;
   
     void set_buffer_size(int sz) { policy_.set_buffer_size(sz); }
   
     IProcessor *parent_;   // observing pointer
     PortAddress address_;
   
    private:
     std::string name_;
     PortOutPolicy policy_;
   };
   
   class ISlotIn {
     friend class IPortIn;
     template <typename DATATYPE> friend class PortIn;
     friend class ISlotOut;
   
    public:
     ISlotIn(IPortIn *parent, const SlotAddress &address, int64_t time_out = -1,
             bool cache = false)
         : time_out_(time_out), cache_enabled_(cache), parent_(parent),
           address_(address) {}
   
     virtual ~ISlotIn(){}
   
     const SlotAddress &address() const { return address_; }
     IPortIn *parent() { return parent_; }
   
     void NegotiateUpstream();
     bool connected() const { return upstream_ != nullptr; }
     void ReleaseData();
   
     const SlotAddress &upstream_address() {
       if (upstream_ == nullptr) {
         throw std::runtime_error(
             "Cannot get upstream address: slot is not connected.");
       }
       return upstream_->address();
     }
   
     const PortOutPolicy &upstream_policy() const {
       if (upstream_ == nullptr) {
         throw std::runtime_error(
             "Cannot get upstream policy: slot is not connected.");
       }
       return upstream_->parent()->policy();
     }
   
     virtual void Validate() = 0;
   
    protected:
     // called by upstream ISlotOut
     RingSequence *sequence() { return &sequence_; }
   
     // called by IPortIn
     void Connect(ISlotOut *upstream);
     void PrepareProcessing();
   
    protected:
     int64_t time_out_;
     bool cache_enabled_;
     int64_t ncached_ = 0;
     int64_t nretrieved_ = 0;
   
     typename AnyType::Data *cache_ = nullptr;
     // access to upstream slot needs to go through base pointer
     // (since we don't know the exact datatype)
     ISlotOut *upstream_ = nullptr;
   
     RingSequence sequence_;   // the input slot's read cursor into the buffer
     IPortIn *parent_;   // observing pointer
     SlotAddress address_;
   };
   
   class IPortIn {
     friend class ProcessorEngine;
     friend class IProcessor;
   
    public:
     IPortIn(IProcessor *parent, const PortAddress &address, PortInPolicy policy)
         : parent_(parent), address_(address), policy_(policy) {}
   
     virtual ~IPortIn(){}
   
     const PortAddress &address() const { return address_; }
     const PortInPolicy &policy() const { return policy_; }
     IProcessor *parent() { return parent_; }
   
     virtual std::string datatype() const = 0;
     virtual SlotType number_of_slots() const = 0;
     virtual ISlotIn *slot(std::size_t index) = 0;
   
     YAML::Node ExportYAML() const;
     std::string name() const { return address_.port(); }
   
    protected:
     // called by StreamInConnector
     virtual void Connect(int slot, ISlotOut *upstream) = 0;
     virtual int ReserveSlot(int slot) = 0;
     virtual void VerifyCompatibility(IPortOut *upstream) = 0;
     // called by ...
     virtual void PrepareProcessing() = 0;
     virtual void UnlockSlots() = 0;
   
     IProcessor *parent_;  // observing pointer
     PortAddress address_;
   
    private:
     std::string name_;
     PortInPolicy policy_;
   
   };