Support state saving and serialisation for FMI2

Closes #4.

cppfmu_common.hpp

@@ -43,13 +43,15 @@ namespace cppfmu
     typedef fmiInteger FMIInteger;
     typedef fmiBoolean FMIBoolean;
     typedef fmiString FMIString;
+    typedef char FMIByte; // doesn't exist in FMI 1
     typedef fmiCallbackFunctions FMICallbackFunctions;
     typedef fmiCallbackAllocateMemory FMICallbackAllocateMemory;
     typedef fmiCallbackFreeMemory FMICallbackFreeMemory;
     typedef fmiCallbackLogger FMICallbackLogger;
     typedef fmiComponent FMIComponent;
     typedef fmiComponent FMIComponentEnvironment;
     typedef fmiStatus FMIStatus;
+    typedef void* FMIFMUState; // doesn't exist in FMI 1
     typedef fmiValueReference FMIValueReference;
 
     const FMIBoolean FMIFalse = fmiFalse;
@@ -66,12 +68,14 @@ namespace cppfmu
     typedef fmi2Integer FMIInteger;
     typedef fmi2Boolean FMIBoolean;
     typedef fmi2String FMIString;
+    typedef fmi2Byte FMIByte;
     typedef fmi2CallbackFunctions FMICallbackFunctions;
     typedef fmi2CallbackAllocateMemory FMICallbackAllocateMemory;
     typedef fmi2CallbackFreeMemory FMICallbackFreeMemory;
     typedef fmi2CallbackLogger FMICallbackLogger;
     typedef fmi2Component FMIComponent;
     typedef fmi2ComponentEnvironment FMIComponentEnvironment;
+    typedef fmi2FMUstate FMIFMUState;
     typedef fmi2Status FMIStatus;
     typedef fmi2ValueReference FMIValueReference;
 

cppfmu_cs.cpp

@@ -139,6 +139,48 @@ void SlaveInstance::GetString(
 }
 
 
+void SlaveInstance::GetFMUState(FMIFMUState* state)
+{
+    throw std::logic_error("Operation not supported: get FMU state");
+}
+
+
+void SlaveInstance::SetFMUState(FMIFMUState state)
+{
+    throw std::logic_error("Operation not supported: set FMU state");
+}
+
+
+void SlaveInstance::FreeFMUState(FMIFMUState state)
+{
+    throw std::logic_error("Operation not supported: free FMU state");
+}
+
+
+std::size_t SlaveInstance::SerializedFMUStateSize(FMIFMUState state)
+{
+    throw std::logic_error("Operation not supported: get serialized FMU state size");
+}
+
+
+void SlaveInstance::SerializeFMUState(
+    FMIFMUState state,
+    FMIByte data[],
+    std::size_t size)
+{
+    throw std::logic_error("Operation not supported: serialize FMU state");
+}
+
+
+FMIFMUState SlaveInstance::DeserializeFMUState(
+    const FMIByte data[],
+    std::size_t size)
+{
+    throw std::logic_error("Operation not supported: deserialize FMU state");
+}
+
+
+
 SlaveInstance::~SlaveInstance() CPPFMU_NOEXCEPT
 {
     // Do nothing

cppfmu_cs.hpp

@@ -103,6 +103,47 @@ class SlaveInstance
         std::size_t nvr,
         FMIString value[]) const;
 
+    /* Called from fmi2GetFMUState().
+     * Never called with FMI 1.x.
+     * Throws std::logic_error by default.
+     */
+    virtual void GetFMUState(FMIFMUState* state);
+
+    /* Called from fmi2SetFMUstate().
+     * Never called with FMI 1.x.
+     * Throws std::logic_error by default.
+     */
+    virtual void SetFMUState(FMIFMUState state);
+
+    /* Called from fmi2FreeFMUstate().
+     * Never called with FMI 1.x.
+     * Throws std::logic_error by default.
+     */
+    virtual void FreeFMUState(FMIFMUState state);
+
+    /* Called from fmi2SerializedFMUstateSize().
+     * Never called with FMI 1.x.
+     * Throws std::logic_error by default.
+     */
+    virtual std::size_t SerializedFMUStateSize(FMIFMUState state);
+
+    /* Called from fmi2SerializeFMUstate().
+     * Never called with FMI 1.x.
+     * Throws std::logic_error by default.
+     */
+    virtual void SerializeFMUState(
+        FMIFMUState state,
+        FMIByte data[],
+        std::size_t size);
+
+    /* Called from fmi2DeSerializeFMUstate().
+     * Never called with FMI 1.x.
+     * Throws std::logic_error by default.
+     */
+    virtual FMIFMUState DeserializeFMUState(
+        const FMIByte data[],
+        std::size_t size);
+
     // Called from fmi2DoStep()/fmiDoStep(). Must be implemented in model code.
     virtual bool DoStep(
         FMIReal currentCommunicationPoint,

fmi_functions.cpp

@@ -1,4 +1,4 @@
-/* Copyright 2016-2019, SINTEF Ocean.
+/* Copyright 2016-2024, SINTEF Ocean.
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
@@ -798,73 +798,111 @@ fmi2Status fmi2SetString(
 
 fmi2Status fmi2GetFMUstate(
     fmi2Component c,
-    fmi2FMUstate*)
+    fmi2FMUstate* state)
 {
-    reinterpret_cast<Component*>(c)->logger.Log(
-        fmi2Error,
-        "cppfmu",
-        "FMI function not supported: fmi2GetFMUstate");
-    return fmi2Error;
+    const auto component = reinterpret_cast<Component*>(c);
+    try {
+        component->slave->GetFMUState(state);
+        return fmi2OK;
+    } catch (const cppfmu::FatalError& e) {
+        component->logger.Log(fmi2Fatal, "", e.what());
+        return fmi2Fatal;
+    } catch (const std::exception& e) {
+        component->logger.Log(fmi2Error, "", e.what());
+        return fmi2Error;
+    }
 }
 
 fmi2Status fmi2SetFMUstate(
     fmi2Component c,
-    fmi2FMUstate)
+    fmi2FMUstate state)
 {
-    reinterpret_cast<Component*>(c)->logger.Log(
-        fmi2Error,
-        "cppfmu",
-        "FMI function not supported: fmi2SetFMUstate");
-    return fmi2Error;
+    const auto component = reinterpret_cast<Component*>(c);
+    try {
+        component->slave->SetFMUState(state);
+        return fmi2OK;
+    } catch (const cppfmu::FatalError& e) {
+        component->logger.Log(fmi2Fatal, "", e.what());
+        return fmi2Fatal;
+    } catch (const std::exception& e) {
+        component->logger.Log(fmi2Error, "", e.what());
+        return fmi2Error;
+    }
 }
 
 fmi2Status fmi2FreeFMUstate(
     fmi2Component c,
-    fmi2FMUstate*)
+    fmi2FMUstate* state)
 {
-    reinterpret_cast<Component*>(c)->logger.Log(
-        fmi2Error,
-        "cppfmu",
-        "FMI function not supported: fmi2FreeFMUstate");
-    return fmi2Error;
+    if (state == nullptr) return fmi2OK;
+    const auto component = reinterpret_cast<Component*>(c);
+    try {
+        component->slave->FreeFMUState(*state);
+        *state = nullptr;
+        return fmi2OK;
+    } catch (const cppfmu::FatalError& e) {
+        component->logger.Log(fmi2Fatal, "", e.what());
+        return fmi2Fatal;
+    } catch (const std::exception& e) {
+        component->logger.Log(fmi2Error, "", e.what());
+        return fmi2Error;
+    }
 }
 
 fmi2Status fmi2SerializedFMUstateSize(
     fmi2Component c,
-    fmi2FMUstate,
-    size_t*)
+    fmi2FMUstate state,
+    size_t* size)
 {
-    reinterpret_cast<Component*>(c)->logger.Log(
-        fmi2Error,
-        "cppfmu",
-        "FMI function not supported: fmi2SerializedFMUstateSize");
-    return fmi2Error;
+    const auto component = reinterpret_cast<Component*>(c);
+    try {
+        *size = component->slave->SerializedFMUStateSize(state);
+        return fmi2OK;
+    } catch (const cppfmu::FatalError& e) {
+        component->logger.Log(fmi2Fatal, "", e.what());
+        return fmi2Fatal;
+    } catch (const std::exception& e) {
+        component->logger.Log(fmi2Error, "", e.what());
+        return fmi2Error;
+    }
 }
 
 fmi2Status fmi2SerializeFMUstate(
     fmi2Component c,
-    fmi2FMUstate,
-    fmi2Byte[],
-    size_t)
+    fmi2FMUstate state,
+    fmi2Byte data[],
+    size_t size)
 {
-    reinterpret_cast<Component*>(c)->logger.Log(
-        fmi2Error,
-        "cppfmu",
-        "FMI function not supported: fmi2SerializeFMUstate");
-    return fmi2Error;
+    const auto component = reinterpret_cast<Component*>(c);
+    try {
+        component->slave->SerializeFMUState(state, data, size);
+        return fmi2OK;
+    } catch (const cppfmu::FatalError& e) {
+        component->logger.Log(fmi2Fatal, "", e.what());
+        return fmi2Fatal;
+    } catch (const std::exception& e) {
+        component->logger.Log(fmi2Error, "", e.what());
+        return fmi2Error;
+    }
 }
 
 fmi2Status fmi2DeSerializeFMUstate(
     fmi2Component c,
-    const fmi2Byte[],
-    size_t,
-    fmi2FMUstate*)
+    const fmi2Byte data[],
+    size_t size,
+    fmi2FMUstate* state)
 {
-    reinterpret_cast<Component*>(c)->logger.Log(
-        fmi2Error,
-        "cppfmu",
-        "FMI function not supported: fmi2DeSerializeFMUstate");
-    return fmi2Error;
+    const auto component = reinterpret_cast<Component*>(c);
+    try {
+        *state = component->slave->DeserializeFMUState(data, size);
+        return fmi2OK;
+    } catch (const cppfmu::FatalError& e) {
+        component->logger.Log(fmi2Fatal, "", e.what());
+        return fmi2Fatal;
+    } catch (const std::exception& e) {
+        component->logger.Log(fmi2Error, "", e.what());
+        return fmi2Error;
+    }
 }
 
 

tests/cs_slave.cpp

@@ -1,11 +1,17 @@
 #include <cppfmu_cs.hpp>
 
+#include <cstring>
 #include <stdexcept>
 
 
 class TestSlave : public cppfmu::SlaveInstance
 {
 public:
+    explicit TestSlave(cppfmu::Memory memory)
+        : memory_(memory)
+    {
+    }
+
     void SetReal(
         const cppfmu::FMIValueReference vr[],
         std::size_t nvr,
@@ -34,6 +40,50 @@ class TestSlave : public cppfmu::SlaveInstance
         }
     }
 
+    void GetFMUState(cppfmu::FMIFMUState* state) override
+    {
+        auto s = (*state == nullptr)
+            ? cppfmu::New<cppfmu::FMIReal>(memory_)
+            : static_cast<cppfmu::FMIReal*>(*state);
+        *s = value_;
+        *state = s;
+    }
+
+    void SetFMUState(cppfmu::FMIFMUState state) override
+    {
+        auto s = static_cast<cppfmu::FMIReal*>(state);
+        value_ = *s;
+    }
+
+    void FreeFMUState(cppfmu::FMIFMUState state) override
+    {
+        auto s = static_cast<cppfmu::FMIReal*>(state);
+        cppfmu::Delete(memory_, s);
+    }
+
+    std::size_t SerializedFMUStateSize(cppfmu::FMIFMUState) override
+    {
+        return sizeof(cppfmu::FMIReal);
+    }
+
+    void SerializeFMUState(
+        cppfmu::FMIFMUState state,
+        cppfmu::FMIByte data[],
+        std::size_t size) override
+    {
+        auto s = static_cast<cppfmu::FMIReal*>(state);
+        std::memcpy(data, s, sizeof *s);
+    }
+
+    cppfmu::FMIFMUState DeserializeFMUState(
+        const cppfmu::FMIByte data[],
+        std::size_t size) override
+    {
+        auto s = cppfmu::New<cppfmu::FMIReal>(memory_);
+        std::memcpy(s, data, sizeof *s);
+        return s;
+    }
+
     bool DoStep(
         cppfmu::FMIReal currentCommunicationPoint,
         cppfmu::FMIReal communicationStepSize,
@@ -44,6 +94,7 @@ class TestSlave : public cppfmu::SlaveInstance
     }
 
 private:
+    cppfmu::Memory memory_;
     cppfmu::FMIReal value_ = 0.0;
 };
 
@@ -59,6 +110,6 @@ cppfmu::UniquePtr<cppfmu::SlaveInstance> CppfmuInstantiateSlave(
     cppfmu::Memory memory,
     cppfmu::Logger logger)
 {
-    return cppfmu::AllocateUnique<TestSlave>(memory);
+    return cppfmu::AllocateUnique<TestSlave>(memory, memory);
 }