Sample Code
Windows Driver Samples/ WPD service sample driver/ C++/ WpdObjectResources.cpp/
#include "stdafx.h" #include "WpdObjectResources.tmh" WpdObjectResources::WpdObjectResources() : m_pDevice(NULL) { } WpdObjectResources::~WpdObjectResources() { } HRESULT WpdObjectResources::Initialize(_In_ FakeDevice* pDevice) { if (pDevice == NULL) { return E_POINTER; } m_pDevice = pDevice; return S_OK; } HRESULT WpdObjectResources::DispatchWpdMessage( _In_ REFPROPERTYKEY Command, _In_ IPortableDeviceValues* pParams, _In_ IPortableDeviceValues* pResults) { HRESULT hr = S_OK; if (hr == S_OK) { if (Command.fmtid != WPD_CATEGORY_OBJECT_RESOURCES) { hr = E_INVALIDARG; CHECK_HR(hr, "This object does not support this command category %ws",CComBSTR(Command.fmtid)); } } if (hr == S_OK) { if (IsEqualPropertyKey(Command, WPD_COMMAND_OBJECT_RESOURCES_GET_SUPPORTED)) { hr = OnGetSupportedResources(pParams, pResults); CHECK_HR(hr, "Failed to get supported resources"); } else if (IsEqualPropertyKey(Command, WPD_COMMAND_OBJECT_RESOURCES_OPEN)) { hr = OnOpenResource(pParams, pResults); CHECK_HR(hr, "Failed to open resource"); } else if (IsEqualPropertyKey(Command, WPD_COMMAND_OBJECT_RESOURCES_READ)) { hr = OnReadResource(pParams, pResults); CHECK_HR(hr, "Failed to read resource"); } else if (IsEqualPropertyKey(Command, WPD_COMMAND_OBJECT_RESOURCES_CLOSE)) { hr = OnCloseResource(pParams, pResults); CHECK_HR(hr, "Failed to close resource"); } else if (IsEqualPropertyKey(Command, WPD_COMMAND_OBJECT_RESOURCES_GET_ATTRIBUTES)) { hr = OnGetResourceAttributes(pParams, pResults); CHECK_HR(hr, "Failed to get resource attributes"); } else { hr = E_NOTIMPL; CHECK_HR(hr, "This object does not support this command id %d", Command.pid); } } return hr; } /** * This method is called when we receive a WPD_COMMAND_OBJECT_RESOURCES_GET_SUPPORTED * command. * * The parameters sent to us are: * - WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID: identifies the object whose resources we want to return. * * The driver should: * - Return all resources for this object in WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS. */ HRESULT WpdObjectResources::OnGetSupportedResources( _In_ IPortableDeviceValues* pParams, _In_ IPortableDeviceValues* pResults) { HRESULT hr = S_OK; LPWSTR wszObjectID = NULL; CComPtr<IPortableDeviceKeyCollection> pKeys; // Get the Object ID hr = pParams->GetStringValue(WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID, &wszObjectID); if (hr != S_OK) { hr = E_INVALIDARG; CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID"); } // Create the collection to hold the resource keys if (hr == S_OK) { hr = CoCreateInstance(CLSID_PortableDeviceKeyCollection, NULL, CLSCTX_INPROC_SERVER, IID_IPortableDeviceKeyCollection, (VOID**) &pKeys); CHECK_HR(hr, "Failed to CoCreate CLSID_PortableDeviceKeyCollection"); } if (hr == S_OK) { ACCESS_SCOPE Scope = m_pDevice->GetAccessScope(pParams); hr = m_pDevice->GetSupportedResources(Scope, wszObjectID, pKeys); CHECK_HR(hr, "Failed to get supported resources for object '%ws'", wszObjectID); } if (hr == S_OK) { hr = pResults->SetIUnknownValue(WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS, pKeys); CHECK_HR(hr, "Failed to set WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS"); } // Free the memory. CoTaskMemFree ignores NULLs so no need to check. CoTaskMemFree(wszObjectID); return hr; } /** * This method is called when we receive a WPD_COMMAND_OBJECT_RESOURCES_GET_ATTRIBUTES * command. * * The parameters sent to us are: * - WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID: identifies the object whose resource attributes we want to return. * - WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS: a collection of property keys containing a single value, * which is the key identifying the specific resource we are requested to return attributes for. * * The driver should: * - Return the requested property attributes in WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_ATTRIBUTES. * If any resource attributes failed to be retrieved, * the corresponding value should be set to type VT_ERROR with the 'scode' member holding the * HRESULT reason for the failure. * - S_OK should be returned if all resource attributes were read successfully. * - S_FALSE should be returned if any resource attribute failed. * - Any error return indicates that the driver did not fill in any results, and the caller will * not attempt to unpack any property values. * */ HRESULT WpdObjectResources::OnGetResourceAttributes( _In_ IPortableDeviceValues* pParams, _In_ IPortableDeviceValues* pResults) { HRESULT hr = S_OK; LPWSTR wszObjectID = NULL; PROPERTYKEY Key = WPD_PROPERTY_NULL; CComPtr<IPortableDeviceValues> pAttributes; if (hr == S_OK) { hr = pParams->GetStringValue(WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID, &wszObjectID); CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID"); } if (hr == S_OK) { hr = pParams->GetKeyValue(WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS, &Key); CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS"); } if (hr == S_OK) { hr = CoCreateInstance(CLSID_PortableDeviceValues, NULL, CLSCTX_INPROC_SERVER, IID_IPortableDeviceValues, (VOID**) &pAttributes); CHECK_HR(hr, "Failed to CoCreate CLSID_PortableDeviceValues"); } if (hr == S_OK) { ACCESS_SCOPE Scope = m_pDevice->GetAccessScope(pParams); hr = m_pDevice->GetResourceAttributes(Scope, wszObjectID, Key, pAttributes); CHECK_HR(hr, "Failed to get resource attributes"); } if (SUCCEEDED(hr)) { HRESULT hrTemp = S_OK; hrTemp = pResults->SetIPortableDeviceValuesValue(WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_ATTRIBUTES, pAttributes); CHECK_HR(hrTemp, ("Failed to set WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_ATTRIBUTES")); if(FAILED(hrTemp)) { hr = hrTemp; } } // Free the memory. CoTaskMemFree ignores NULLs so no need to check. CoTaskMemFree(wszObjectID); return hr; } /** * This method is called when we receive a WPD_COMMAND_OBJECT_RESOURCES_OPEN * command. * * The parameters sent to us are: * - WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID: the object identifier of the * object which contains the specified resource * * - WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS: the specified resource * to open * * - WPD_PROPERTY_OBJECT_RESOURCES_ACCESS_MODE: the access mode to which to * open the specified resource * * The driver should: * - Create a new context for this resource operation. * - Return an identifier for the context in WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT. * - Set the optimal transfer size in WPD_PROPERTY_OBJECT_RESOURCES_OPTIMAL_TRANSFER_BUFFER_SIZE * */ HRESULT WpdObjectResources::OnOpenResource( _In_ IPortableDeviceValues* pParams, _In_ IPortableDeviceValues* pResults) { HRESULT hr = S_OK; LPWSTR wszObjectID = NULL; PROPERTYKEY Key = WPD_PROPERTY_NULL; DWORD dwMode = STGM_READ; CAtlStringW strStrObjectID; CAtlStringW strResourceContext; ContextMap* pContextMap = NULL; // Get the Object identifier of the object which contains the specified resource hr = pParams->GetStringValue(WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID, &wszObjectID); if (FAILED(hr)) { hr = E_INVALIDARG; CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_OBJECT_ID"); } // Get the resource key if (SUCCEEDED(hr)) { hr = pParams->GetKeyValue(WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS, &Key); CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_RESOURCE_KEYS"); } // Get the access mode if (SUCCEEDED(hr)) { hr = pParams->GetUnsignedIntegerValue(WPD_PROPERTY_OBJECT_RESOURCES_ACCESS_MODE, &dwMode); CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_ACCESS_MODE"); } // Get the context map which the driver stored in pParams for convenience if (SUCCEEDED(hr)) { hr = GetClientContextMap(pParams, &pContextMap); CHECK_HR(hr, "Failed to get the client context map"); } // Create a new resource operation context, initialize it, and add it to the client context map. if (SUCCEEDED(hr)) { WpdObjectResourceContext* pResourceContext = new WpdObjectResourceContext(); if (pResourceContext != NULL) { ACCESS_SCOPE Scope = m_pDevice->GetAccessScope(pParams); hr = m_pDevice->OpenResource(Scope, wszObjectID, Key, dwMode, pResourceContext); CHECK_HR(hr, "Failed to open resource"); if (SUCCEEDED(hr)) { // Add the resource context to the context map, this calls AddRef() on pResourceContext hr = pContextMap->Add(pResourceContext, strResourceContext); CHECK_HR(hr, "Failed to add the resource context"); } } else { hr = E_OUTOFMEMORY; CHECK_HR(hr, "Failed to allocate resource context"); } SAFE_RELEASE(pResourceContext); } if (SUCCEEDED(hr)) { hr = pResults->SetStringValue(WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT, strResourceContext); CHECK_HR(hr, "Failed to set WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT"); } // Set the optimal buffer size if (SUCCEEDED(hr)) { hr = pResults->SetUnsignedIntegerValue(WPD_PROPERTY_OBJECT_RESOURCES_OPTIMAL_TRANSFER_BUFFER_SIZE, FILE_OPTIMAL_READ_BUFFER_SIZE_VALUE); CHECK_HR(hr, "Failed to set WPD_PROPERTY_OBJECT_RESOURCES_OPTIMAL_TRANSFER_BUFFER_SIZE value"); } // Free the memory. CoTaskMemFree ignores NULLs so no need to check. CoTaskMemFree(wszObjectID); SAFE_RELEASE(pContextMap); return hr; } /** * This method is called when we receive a WPD_COMMAND_OBJECT_RESOURCES_READ * command. * * The parameters sent to us are: * - WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT: the context the driver returned to * the client in OnOpenResource. * - WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_TO_READ: the number of bytes to * read from the resource. * * The driver should: * - Read data associated with the resource and return it back to the caller in * WPD_PROPERTY_OBJECT_RESOURCES_DATA. * - Report the number of bytes actually read from the resource in * WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_READ. This number may be smaller * than WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_TO_READ when reading the last * chunk of data from the resource. */ HRESULT WpdObjectResources::OnReadResource( _In_ IPortableDeviceValues* pParams, _In_ IPortableDeviceValues* pResults) { HRESULT hr = S_OK; LPWSTR wszResourceContext = NULL; DWORD dwNumBytesToRead = 0; DWORD dwNumBytesRead = 0; BYTE* pBuffer = NULL; WpdObjectResourceContext* pResourceContext = NULL; // Get the enumeration context identifier for this enumeration operation. We will // need this to lookup the specific enumeration context in the client context map. hr = pParams->GetStringValue(WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT, &wszResourceContext); if (FAILED(hr)) { hr = E_INVALIDARG; CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT"); } // Get the number of bytes to read if (SUCCEEDED(hr)) { hr = pParams->GetUnsignedIntegerValue(WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_TO_READ, &dwNumBytesToRead); CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_TO_READ"); } // Allocate the destination buffer if (SUCCEEDED(hr)) { pBuffer = reinterpret_cast<BYTE *>(CoTaskMemAlloc(dwNumBytesToRead)); if (pBuffer == NULL) { hr = E_OUTOFMEMORY; CHECK_HR(hr, "Failed to allocate the destination buffer"); } } // Get the client context map so we can retrieve the resource context for this resource // operation using the WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT property value obtained above. if (SUCCEEDED(hr)) { hr = GetClientContext(pParams, wszResourceContext, (IUnknown**)&pResourceContext); CHECK_HR(hr, "Failed to get the resource context"); } // Read the next chunk of data for this request if (SUCCEEDED(hr)) { hr = m_pDevice->ReadResourceData(pResourceContext, pBuffer, dwNumBytesToRead, &dwNumBytesRead); CHECK_HR(hr, "Failed to read %d bytes from resource", dwNumBytesToRead); } if (SUCCEEDED(hr)) { pResourceContext->m_BytesTransferred += dwNumBytesRead; hr = pResults->SetBufferValue(WPD_PROPERTY_OBJECT_RESOURCES_DATA, pBuffer, dwNumBytesRead); CHECK_HR(hr, "Failed to set WPD_PROPERTY_OBJECT_RESOURCES_DATA"); } if (SUCCEEDED(hr)) { hr = pResults->SetUnsignedIntegerValue(WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_READ, dwNumBytesRead); CHECK_HR(hr, "Failed to set WPD_PROPERTY_OBJECT_RESOURCES_NUM_BYTES_READ"); } // Free the memory. CoTaskMemFree ignores NULLs so no need to check. CoTaskMemFree(wszResourceContext); // Free the memory. CoTaskMemFree ignores NULLs so no need to check. CoTaskMemFree(pBuffer); return hr; } /** * This method is called when we receive a WPD_COMMAND_OBJECT_RESOURCES_CLOSE * command. * * The parameters sent to us are: * - WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT: the context the driver returned to * the client in OnOpenResource. * * The driver should: * - Destroy any data associated with this context. */ HRESULT WpdObjectResources::OnCloseResource( _In_ IPortableDeviceValues* pParams, _In_ IPortableDeviceValues* pResults) { HRESULT hr = S_OK; LPWSTR wszResourceContext = NULL; ContextMap* pContextMap = NULL; UNREFERENCED_PARAMETER(pResults); // First get ALL parameters for this command. If we cannot get ALL parameters // then E_INVALIDARG should be returned and no further processing should occur. // Get the resource context identifier for this resource operation. We will // need this to lookup the specific resource context in the client context map. hr = pParams->GetStringValue(WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT, &wszResourceContext); if (FAILED(hr)) { hr = E_INVALIDARG; CHECK_HR(hr, "Missing value for WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT"); } // Get the client context map so we can retrieve the resource context for this resource // operation using the WPD_PROPERTY_OBJECT_RESOURCES_CONTEXT property value obtained above. if (SUCCEEDED(hr)) { hr = GetClientContextMap(pParams, &pContextMap); CHECK_HR(hr, "Failed to get the client context map"); } // Destroy any data allocated/associated with the resource context and then remove it from the context map. // We no longer need to keep this context around because the resource operation has been ended. if (SUCCEEDED(hr)) { pContextMap->Remove(wszResourceContext); } // Free the memory. CoTaskMemFree ignores NULLs so no need to check. CoTaskMemFree(wszResourceContext); SAFE_RELEASE(pContextMap); return hr; }
Our Services
-
What our customers say about us?
Read our customer testimonials to find out why our clients keep returning for their projects.
View Testimonials