// Support back to Vista
#define _WIN32_WINNT _WIN32_WINNT_VISTA
#include <sdkddkver.h>
// Use WRL to define a classic COM class
#define __WRL_CLASSIC_COM__
#include <wrl.h>
#include <windows.h>
#include <shlobj.h>
#include <shlwapi.h>
#include <olectl.h>
#include <strsafe.h>
#include "pyshellext_h.h"
#define DDWM_UPDATEWINDOW (WM_USER+3)
static HINSTANCE hModule;
static CLIPFORMAT cfDropDescription;
static CLIPFORMAT cfDragWindow;
static const LPCWSTR CLASS_SUBKEY = L"Software\\Classes\\CLSID\\{BEA218D2-6950-497B-9434-61683EC065FE}";
static const LPCWSTR DRAG_MESSAGE = L"Open with %1";
using namespace Microsoft::WRL;
HRESULT FilenameListCchLengthA(LPCSTR pszSource, size_t cchMax, size_t *pcchLength, size_t *pcchCount) {
HRESULT hr = S_OK;
size_t count = 0;
size_t length = 0;
while (pszSource && pszSource[0]) {
size_t oneLength;
hr = StringCchLengthA(pszSource, cchMax - length, &oneLength);
if (FAILED(hr)) {
return hr;
}
count += 1;
length += oneLength + (strchr(pszSource, ' ') ? 3 : 1);
pszSource = &pszSource[oneLength + 1];
}
*pcchCount = count;
*pcchLength = length;
return hr;
}
HRESULT FilenameListCchLengthW(LPCWSTR pszSource, size_t cchMax, size_t *pcchLength, size_t *pcchCount) {
HRESULT hr = S_OK;
size_t count = 0;
size_t length = 0;
while (pszSource && pszSource[0]) {
size_t oneLength;
hr = StringCchLengthW(pszSource, cchMax - length, &oneLength);
if (FAILED(hr)) {
return hr;
}
count += 1;
length += oneLength + (wcschr(pszSource, ' ') ? 3 : 1);
pszSource = &pszSource[oneLength + 1];
}
*pcchCount = count;
*pcchLength = length;
return hr;
}
HRESULT FilenameListCchCopyA(STRSAFE_LPSTR pszDest, size_t cchDest, LPCSTR pszSource, LPCSTR pszSeparator) {
HRESULT hr = S_OK;
size_t count = 0;
size_t length = 0;
while (pszSource[0]) {
STRSAFE_LPSTR newDest;
hr = StringCchCopyExA(pszDest, cchDest, pszSource, &newDest, &cchDest, 0);
if (FAILED(hr)) {
return hr;
}
pszSource += (newDest - pszDest) + 1;
pszDest = PathQuoteSpacesA(pszDest) ? newDest + 2 : newDest;
if (pszSource[0]) {
hr = StringCchCopyExA(pszDest, cchDest, pszSeparator, &newDest, &cchDest, 0);
if (FAILED(hr)) {
return hr;
}
pszDest = newDest;
}
}
return hr;
}
HRESULT FilenameListCchCopyW(STRSAFE_LPWSTR pszDest, size_t cchDest, LPCWSTR pszSource, LPCWSTR pszSeparator) {
HRESULT hr = S_OK;
size_t count = 0;
size_t length = 0;
while (pszSource[0]) {
STRSAFE_LPWSTR newDest;
hr = StringCchCopyExW(pszDest, cchDest, pszSource, &newDest, &cchDest, 0);
if (FAILED(hr)) {
return hr;
}
pszSource += (newDest - pszDest) + 1;
pszDest = PathQuoteSpacesW(pszDest) ? newDest + 2 : newDest;
if (pszSource[0]) {
hr = StringCchCopyExW(pszDest, cchDest, pszSeparator, &newDest, &cchDest, 0);
if (FAILED(hr)) {
return hr;
}
pszDest = newDest;
}
}
return hr;
}
class PyShellExt : public RuntimeClass<
RuntimeClassFlags<ClassicCom>,
IDropTarget,
IPersistFile
>
{
LPOLESTR target, target_dir;
DWORD target_mode;
IDataObject *data_obj;
public:
PyShellExt() : target(NULL), target_dir(NULL), target_mode(0), data_obj(NULL) {
OutputDebugString(L"PyShellExt::PyShellExt");
}
~PyShellExt() {
if (target) {
CoTaskMemFree(target);
}
if (target_dir) {
CoTaskMemFree(target_dir);
}
if (data_obj) {
data_obj->Release();
}
}
private:
HRESULT UpdateDropDescription(IDataObject *pDataObj) {
STGMEDIUM medium;
FORMATETC fmt = {
cfDropDescription,
NULL,
DVASPECT_CONTENT,
-1,
TYMED_HGLOBAL
};
auto hr = pDataObj->GetData(&fmt, &medium);
if (FAILED(hr)) {
OutputDebugString(L"PyShellExt::UpdateDropDescription - failed to get DROPDESCRIPTION format");
return hr;
}
if (!medium.hGlobal) {
OutputDebugString(L"PyShellExt::UpdateDropDescription - DROPDESCRIPTION format had NULL hGlobal");
ReleaseStgMedium(&medium);
return E_FAIL;
}
auto dd = (DROPDESCRIPTION*)GlobalLock(medium.hGlobal);
StringCchCopy(dd->szMessage, sizeof(dd->szMessage) / sizeof(dd->szMessage[0]), DRAG_MESSAGE);
StringCchCopy(dd->szInsert, sizeof(dd->szInsert) / sizeof(dd->szInsert[0]), PathFindFileNameW(target));
dd->type = DROPIMAGE_MOVE;
GlobalUnlock(medium.hGlobal);
ReleaseStgMedium(&medium);
return S_OK;
}
HRESULT GetDragWindow(IDataObject *pDataObj, HWND *phWnd) {
HRESULT hr;
HWND *pMem;
STGMEDIUM medium;
FORMATETC fmt = {
cfDragWindow,
NULL,
DVASPECT_CONTENT,
-1,
TYMED_HGLOBAL
};
hr = pDataObj->GetData(&fmt, &medium);
if (FAILED(hr)) {
OutputDebugString(L"PyShellExt::GetDragWindow - failed to get DragWindow format");
return hr;
}
if (!medium.hGlobal) {
OutputDebugString(L"PyShellExt::GetDragWindow - DragWindow format had NULL hGlobal");
ReleaseStgMedium(&medium);
return E_FAIL;
}
pMem = (HWND*)GlobalLock(medium.hGlobal);
if (!pMem) {
OutputDebugString(L"PyShellExt::GetDragWindow - failed to lock DragWindow hGlobal");
ReleaseStgMedium(&medium);
return E_FAIL;
}
*phWnd = *pMem;
GlobalUnlock(medium.hGlobal);
ReleaseStgMedium(&medium);
return S_OK;
}
HRESULT GetArguments(IDataObject *pDataObj, LPCWSTR *pArguments) {
HRESULT hr;
DROPFILES *pdropfiles;
STGMEDIUM medium;
FORMATETC fmt = {
CF_HDROP,
NULL,
DVASPECT_CONTENT,
-1,
TYMED_HGLOBAL
};
hr = pDataObj->GetData(&fmt, &medium);
if (FAILED(hr)) {
OutputDebugString(L"PyShellExt::GetArguments - failed to get CF_HDROP format");
return hr;
}
if (!medium.hGlobal) {
OutputDebugString(L"PyShellExt::GetArguments - CF_HDROP format had NULL hGlobal");
ReleaseStgMedium(&medium);
return E_FAIL;
}
pdropfiles = (DROPFILES*)GlobalLock(medium.hGlobal);
if (!pdropfiles) {
OutputDebugString(L"PyShellExt::GetArguments - failed to lock CF_HDROP hGlobal");
ReleaseStgMedium(&medium);
return E_FAIL;
}
if (pdropfiles->fWide) {
LPCWSTR files = (LPCWSTR)((char*)pdropfiles + pdropfiles->pFiles);
size_t len, count;
hr = FilenameListCchLengthW(files, 32767, &len, &count);
if (SUCCEEDED(hr)) {
LPWSTR args = (LPWSTR)CoTaskMemAlloc(sizeof(WCHAR) * (len + 1));
if (args) {
hr = FilenameListCchCopyW(args, 32767, files, L" ");
if (SUCCEEDED(hr)) {
*pArguments = args;
} else {
CoTaskMemFree(args);
}
} else {
hr = E_OUTOFMEMORY;
}
}
} else {
LPCSTR files = (LPCSTR)((char*)pdropfiles + pdropfiles->pFiles);
size_t len, count;
hr = FilenameListCchLengthA(files, 32767, &len, &count);
if (SUCCEEDED(hr)) {
LPSTR temp = (LPSTR)CoTaskMemAlloc(sizeof(CHAR) * (len + 1));
if (temp) {
hr = FilenameListCchCopyA(temp, 32767, files, " ");
if (SUCCEEDED(hr)) {
int wlen = MultiByteToWideChar(CP_ACP, 0, temp, (int)len, NULL, 0);
if (wlen) {
LPWSTR args = (LPWSTR)CoTaskMemAlloc(sizeof(WCHAR) * (wlen + 1));
if (MultiByteToWideChar(CP_ACP, 0, temp, (int)len, args, wlen + 1)) {
*pArguments = args;
} else {
OutputDebugString(L"PyShellExt::GetArguments - failed to convert multi-byte to wide-char path");
CoTaskMemFree(args);
hr = E_FAIL;
}
} else {
OutputDebugString(L"PyShellExt::GetArguments - failed to get length of wide-char path");
hr = E_FAIL;
}
}
CoTaskMemFree(temp);
} else {
hr = E_OUTOFMEMORY;
}
}
}
GlobalUnlock(medium.hGlobal);
ReleaseStgMedium(&medium);
return hr;
}
HRESULT NotifyDragWindow(HWND hwnd) {
LRESULT res;
if (!hwnd) {
return S_FALSE;
}
res = SendMessage(hwnd, DDWM_UPDATEWINDOW, 0, NULL);
if (res) {
OutputDebugString(L"PyShellExt::NotifyDragWindow - failed to post DDWM_UPDATEWINDOW");
return E_FAIL;
}
return S_OK;
}
public:
// IDropTarget implementation
STDMETHODIMP DragEnter(IDataObject *pDataObj, DWORD grfKeyState, POINTL pt, DWORD *pdwEffect) {
HWND hwnd;
OutputDebugString(L"PyShellExt::DragEnter");
pDataObj->AddRef();
data_obj = pDataObj;
*pdwEffect = DROPEFFECT_MOVE;
if (FAILED(UpdateDropDescription(data_obj))) {
OutputDebugString(L"PyShellExt::DragEnter - failed to update drop description");
}
if (FAILED(GetDragWindow(data_obj, &hwnd))) {
OutputDebugString(L"PyShellExt::DragEnter - failed to get drag window");
}
if (FAILED(NotifyDragWindow(hwnd))) {
OutputDebugString(L"PyShellExt::DragEnter - failed to notify drag window");
}
return S_OK;
}
STDMETHODIMP DragLeave() {
return S_OK;
}
STDMETHODIMP DragOver(DWORD grfKeyState, POINTL pt, DWORD *pdwEffect) {
return S_OK;
}
STDMETHODIMP Drop(IDataObject *pDataObj, DWORD grfKeyState, POINTL pt, DWORD *pdwEffect) {
LPCWSTR args;
OutputDebugString(L"PyShellExt::Drop");
*pdwEffect = DROPEFFECT_NONE;
if (pDataObj != data_obj) {
OutputDebugString(L"PyShellExt::Drop - unexpected data object");
return E_FAIL;
}
data_obj->Release();
data_obj = NULL;
if (SUCCEEDED(GetArguments(pDataObj, &args))) {
OutputDebugString(args);
ShellExecute(NULL, NULL, target, args, target_dir, SW_NORMAL);
CoTaskMemFree((LPVOID)args);
} else {
OutputDebugString(L"PyShellExt::Drop - failed to get launch arguments");
}
return S_OK;
}
// IPersistFile implementation
STDMETHODIMP GetCurFile(LPOLESTR *ppszFileName) {
HRESULT hr;
size_t len;
if (!ppszFileName) {
return E_POINTER;
}
hr = StringCchLength(target, STRSAFE_MAX_CCH - 1, &len);
if (FAILED(hr)) {
return E_FAIL;
}
*ppszFileName = (LPOLESTR)CoTaskMemAlloc(sizeof(WCHAR) * (len + 1));
if (!*ppszFileName) {
return E_OUTOFMEMORY;
}
hr = StringCchCopy(*ppszFileName, len + 1, target);
if (FAILED(hr)) {
CoTaskMemFree(*ppszFileName);
*ppszFileName = NULL;
return E_FAIL;
}
return S_OK;
}
STDMETHODIMP IsDirty() {
return S_FALSE;
}
STDMETHODIMP Load(LPCOLESTR pszFileName, DWORD dwMode) {
HRESULT hr;
size_t len;
OutputDebugString(L"PyShellExt::Load");
OutputDebugString(pszFileName);
hr = StringCchLength(pszFileName, STRSAFE_MAX_CCH - 1, &len);
if (FAILED(hr)) {
OutputDebugString(L"PyShellExt::Load - failed to get string length");
return hr;
}
if (target) {
CoTaskMemFree(target);
}
if (target_dir) {
CoTaskMemFree(target_dir);
}
target = (LPOLESTR)CoTaskMemAlloc(sizeof(WCHAR) * (len + 1));
if (!target) {
OutputDebugString(L"PyShellExt::Load - E_OUTOFMEMORY");
return E_OUTOFMEMORY;
}
target_dir = (LPOLESTR)CoTaskMemAlloc(sizeof(WCHAR) * (len + 1));
if (!target_dir) {
OutputDebugString(L"PyShellExt::Load - E_OUTOFMEMORY");
return E_OUTOFMEMORY;
}
hr = StringCchCopy(target, len + 1, pszFileName);
if (FAILED(hr)) {
OutputDebugString(L"PyShellExt::Load - failed to copy string");
return hr;
}
hr = StringCchCopy(target_dir, len + 1, pszFileName);
if (FAILED(hr)) {
OutputDebugString(L"PyShellExt::Load - failed to copy string");
return hr;
}
if (!PathRemoveFileSpecW(target_dir)) {
OutputDebugStringW(L"PyShellExt::Load - failed to remove filespec from target");
return E_FAIL;
}
OutputDebugString(target);
target_mode = dwMode;
OutputDebugString(L"PyShellExt::Load - S_OK");
return S_OK;
}
STDMETHODIMP Save(LPCOLESTR pszFileName, BOOL fRemember) {
return E_NOTIMPL;
}
STDMETHODIMP SaveCompleted(LPCOLESTR pszFileName) {
return E_NOTIMPL;
}
STDMETHODIMP GetClassID(CLSID *pClassID) {
*pClassID = CLSID_PyShellExt;
return S_OK;
}
};
CoCreatableClass(PyShellExt);
STDAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, _COM_Outptr_ void** ppv) {
return Module<InProc>::GetModule().GetClassObject(rclsid, riid, ppv);
}
STDAPI DllCanUnloadNow() {
return Module<InProc>::GetModule().Terminate() ? S_OK : S_FALSE;
}
STDAPI DllRegisterServer() {
LONG res;
SECURITY_ATTRIBUTES secattr = { sizeof(SECURITY_ATTRIBUTES), NULL, FALSE };
LPSECURITY_ATTRIBUTES psecattr = NULL;
HKEY key, ipsKey;
WCHAR modname[MAX_PATH];
DWORD modname_len;
OutputDebugString(L"PyShellExt::DllRegisterServer");
if (!hModule) {
OutputDebugString(L"PyShellExt::DllRegisterServer - module handle was not set");
return SELFREG_E_CLASS;
}
modname_len = GetModuleFileName(hModule, modname, MAX_PATH);
if (modname_len == 0 ||
(modname_len == MAX_PATH && GetLastError() == ERROR_INSUFFICIENT_BUFFER)) {
OutputDebugString(L"PyShellExt::DllRegisterServer - failed to get module file name");
return SELFREG_E_CLASS;
}
DWORD disp;
res = RegCreateKeyEx(HKEY_LOCAL_MACHINE, CLASS_SUBKEY, 0, NULL, 0,
KEY_ALL_ACCESS, psecattr, &key, &disp);
if (res == ERROR_ACCESS_DENIED) {
OutputDebugString(L"PyShellExt::DllRegisterServer - failed to write per-machine registration. Attempting per-user instead.");
res = RegCreateKeyEx(HKEY_CURRENT_USER, CLASS_SUBKEY, 0, NULL, 0,
KEY_ALL_ACCESS, psecattr, &key, &disp);
}
if (res != ERROR_SUCCESS) {
OutputDebugString(L"PyShellExt::DllRegisterServer - failed to create class key");
return SELFREG_E_CLASS;
}
res = RegCreateKeyEx(key, L"InProcServer32", 0, NULL, 0,
KEY_ALL_ACCESS, psecattr, &ipsKey, NULL);
if (res != ERROR_SUCCESS) {
RegCloseKey(key);
OutputDebugString(L"PyShellExt::DllRegisterServer - failed to create InProcServer32 key");
return SELFREG_E_CLASS;
}
res = RegSetValueEx(ipsKey, NULL, 0,
REG_SZ, (LPBYTE)modname, modname_len * sizeof(modname[0]));
if (res != ERROR_SUCCESS) {
RegCloseKey(ipsKey);
RegCloseKey(key);
OutputDebugString(L"PyShellExt::DllRegisterServer - failed to set server path");
return SELFREG_E_CLASS;
}
res = RegSetValueEx(ipsKey, L"ThreadingModel", 0,
REG_SZ, (LPBYTE)(L"Apartment"), sizeof(L"Apartment"));
RegCloseKey(ipsKey);
RegCloseKey(key);
if (res != ERROR_SUCCESS) {
OutputDebugString(L"PyShellExt::DllRegisterServer - failed to set threading model");
return SELFREG_E_CLASS;
}
SHChangeNotify(SHCNE_ASSOCCHANGED, SHCNF_IDLIST, NULL, NULL);
OutputDebugString(L"PyShellExt::DllRegisterServer - S_OK");
return S_OK;
}
STDAPI DllUnregisterServer() {
LONG res_lm, res_cu;
res_lm = RegDeleteTree(HKEY_LOCAL_MACHINE, CLASS_SUBKEY);
if (res_lm != ERROR_SUCCESS && res_lm != ERROR_FILE_NOT_FOUND) {
OutputDebugString(L"PyShellExt::DllUnregisterServer - failed to delete per-machine registration");
return SELFREG_E_CLASS;
}
res_cu = RegDeleteTree(HKEY_CURRENT_USER, CLASS_SUBKEY);
if (res_cu != ERROR_SUCCESS && res_cu != ERROR_FILE_NOT_FOUND) {
OutputDebugString(L"PyShellExt::DllUnregisterServer - failed to delete per-user registration");
return SELFREG_E_CLASS;
}
if (res_lm == ERROR_FILE_NOT_FOUND && res_cu == ERROR_FILE_NOT_FOUND) {
OutputDebugString(L"PyShellExt::DllUnregisterServer - extension was not registered");
return SELFREG_E_CLASS;
}
SHChangeNotify(SHCNE_ASSOCCHANGED, SHCNF_IDLIST, NULL, NULL);
OutputDebugString(L"PyShellExt::DllUnregisterServer - S_OK");
return S_OK;
}
STDAPI_(BOOL) DllMain(_In_opt_ HINSTANCE hinst, DWORD reason, _In_opt_ void*) {
if (reason == DLL_PROCESS_ATTACH) {
hModule = hinst;
cfDropDescription = RegisterClipboardFormat(CFSTR_DROPDESCRIPTION);
if (!cfDropDescription) {
OutputDebugString(L"PyShellExt::DllMain - failed to get CFSTR_DROPDESCRIPTION format");
}
cfDragWindow = RegisterClipboardFormat(L"DragWindow");
if (!cfDragWindow) {
OutputDebugString(L"PyShellExt::DllMain - failed to get DragWindow format");
}
DisableThreadLibraryCalls(hinst);
}
return TRUE;
}