Added an API to load model from memory

Source/CNTKv2LibraryDll/API/CNTKLibraryC.h

@@ -109,6 +109,22 @@ CNTK_API CNTK_StatusCode CNTK_LoadModel(
     /*[in]*/ const CNTK_DeviceDescriptor* device,
     /*[out]*/ CNTK_ModelHandle* model);
 
+//
+// Loads a model from the specified buffer and returns an opaque handle to the model
+// that should be passed to further operations.
+//
+// Parameters:
+//     modelData [in]: a buffer that holds the CNTK model
+//     modelDataLen [in]: the length of the buffer
+//     device [in]: device descriptor.
+//     model [out]: the resulting loaded model
+//
+CNTK_StatusCode CNTKModelCompiler_LoadModel_FromArray(
+    /*[in]*/ const void* modelData,
+    /*[in]*/ int modelDataLen,
+    /*[in]*/ const CNTK_DeviceDescriptor* device,
+    /*[out]*/ CNTK_ModelHandle* model);
+
 enum CNTK_ParameterCloningMethod
 {
     ///

Source/CNTKv2LibraryDll/API/Internals/EvaluatorWrapper.h

@@ -152,6 +152,8 @@ namespace CNTK
     public:
         CNTKEvaluatorWrapper(const char* modelFilePath, const CNTK_DeviceDescriptor* device);
         CNTKEvaluatorWrapper(const char* modelFilePath, DeviceDescriptor device);
+        CNTKEvaluatorWrapper(const void* modelData, int modelDataLen, const CNTK_DeviceDescriptor* device);
+        CNTKEvaluatorWrapper(const void* modelData, int modelDataLen, DeviceDescriptor device);
         CNTKEvaluatorWrapper(FunctionPtr model, DeviceDescriptor device);
 
         void GetModelArgumentsInfo(CNTK_Variable** inputs, uint32_t* numInputs) override;

Source/CNTKv2LibraryDll/CNTKLibraryC.cpp

@@ -104,6 +104,22 @@ CNTK_StatusCode CNTK_LoadModel(const char* modelFilePath, const CNTK_DeviceDescr
     return ExceptionCatcher::Call([&]() { *handle = new CNTKEvaluatorWrapper(modelFilePath, device); });
 }
 
+CNTK_StatusCode CNTKModelCompiler_LoadModel_FromArray(const void* modelData, int modelDataLen,
+                                                      const CNTK_DeviceDescriptor* device, CNTK_ModelHandle* handle)
+{
+    if (!handle)
+        return StatusCode(CNTK_ERROR_NULL_POINTER, "'handle' parameter is not allowed to be null");
+
+    if (!modelData)
+        return StatusCode(CNTK_ERROR_NULL_POINTER, "'modelData' parameter is not allowed to be null");
+
+    if (modelDataLen <= 0)
+        return StatusCode(CNTK_ERROR_INVALID_INPUT, "'modelDataLen' parameter must be greater than zero");
+
+    *handle = nullptr;
+    return ExceptionCatcher::Call([&]() { *handle = new CNTKEvaluatorWrapper(modelData, modelDataLen, device); });
+}
+
 CNTK_StatusCode CNTK_CloneModel(CNTK_ModelHandle model, CNTK_ParameterCloningMethod method, bool flatten, CNTK_ModelHandle* cloned)
 {
     if (model == CNTK_INVALID_MODEL_HANDLE)

Source/CNTKv2LibraryDll/EvaluatorWrapper.cpp

@@ -32,6 +32,14 @@ namespace CNTK
         CNTKEvaluatorWrapper(modelFilePath, GetDeviceDescriptor(device))
     {}
 
+    CNTKEvaluatorWrapper::CNTKEvaluatorWrapper(const void* modelData, int modelDataLen, DeviceDescriptor device) :
+        CNTKEvaluatorWrapper(Function::Load(static_cast<const char*>(modelData), modelDataLen, device), device)
+    {}
+
+    CNTKEvaluatorWrapper::CNTKEvaluatorWrapper(const void* modelData, int modelDataLen, const CNTK_DeviceDescriptor* device) :
+        CNTKEvaluatorWrapper(modelData, modelDataLen, GetDeviceDescriptor(device))
+    {}
+
     void CNTKEvaluatorWrapper::GetModelArgumentsInfo(CNTK_Variable** inputs, uint32_t* numInputs)
     {
         assert(inputs != nullptr);