[SHELL32] SHUpdateRecycleBinIcon() part 1

dll/win32/shell32/folders/CRecycleBin.cpp

@@ -1076,6 +1076,70 @@ static void TRASH_PlayEmptyRecycleBinSound()
  */
 EXTERN_C HRESULT WINAPI SHUpdateRecycleBinIcon(void)
 {
+ /*
+ * SHUpdateRecycleBinIcon's logic of updating the trash bin icon is like so, in the following order:
+ *
+ * 1. Determine if the trash bin is empty or not. It first iterates all the drive partitions and
+ * check each of them that one has the location path of the bucket that is associated as the
+ * default bin of the system. Afterwards it loops the bucket of potential remaining files using
+ * the traditional fashion of FindFirstFileW ... FindNextFileW API calls. If the file in question
+ * is a directory (pointed by the FILE_ATTRIBUTE_DIRECTORY attribute) then it iterates over that
+ * directory as well. If at least one or more files have been found (empty directories are taken
+ * into account as well) then the bin is NOT empty.
+ * 2. Query/Set the Registry SHELL32 data. Presumably it queries some information in regard of the
+ * trash bin icons and sets the default value as either "Empty" or "Full" depending on the state
+ * of the bin, I haven't looked much deeper into that.
+ * 3. Expand the environment strings with SHExpandEnvironmentStringsW.
+ * 4. Update the icon image with SHUpdateImageW.
+ * 5. Invoke a notification with SHChangeNotify.
+ */
+
+ BOOL recycleBinEmpty = true, recycleBinEmptySet = false;
+
+ /* First, check to see if the Recycle Bin on any drive has anything in it.*/
+
+ // I do not want to use CString here because this API returns a LPWZZSTR.
+ CHeapPtr<WCHAR> logicalDrivesBuffer;
+ DWORD logicalDrivesBufferLength;
+ logicalDrivesBufferLength = GetLogicalDriveStringsW(0, NULL);
+ logicalDrivesBuffer.Allocate(logicalDrivesBufferLength / sizeof(WCHAR));
+ GetLogicalDriveStringsW(logicalDrivesBufferLength, (LPWSTR)&logicalDrivesBuffer);
+
+ /* For every drive in the system: */
+ LPWSTR logicalDrivesPtr = (LPWSTR)logicalDrivesBuffer.m_pData;
+ while (*logicalDrivesPtr != L'\0')
+ {
+ LPWSTR logicalDrive = logicalDrivesPtr;
+ logicalDrivesPtr += strlenW(logicalDrive) + 1; // count the trailing NUL
+
+ /* Get its recycle bin... */
+ CComPtr<IRecycleBin> recycleBin;
+ HRESULT hr = GetDefaultRecycleBin(logicalDrive, &recycleBin);
+ if (FAILED(hr)) continue;
+
+ /* ...and check if there is anything in it. */
+ CComPtr<IRecycleBinEnumList> recycleBinEnum;
+ hr = recycleBin->EnumObjects(&recycleBinEnum);
+
+ // If the rgelt parameter is NULL, then IRecycleBinEnum::Next() will return an error.
+ CComPtr<IRecycleBinFile> dontCare;
+ hr = recycleBinEnum->Next(1, &dontCare, NULL);
+ if (FAILED(hr)) continue;
+
+ if (hr == S_FALSE)
+ {
+ // The recycle bin is empty. Continue.
+ }
+ else
+ {
+ // There is at least one item in the recycle bin for this drive.
+ // Since we know that the recycle bin is not empty, we can stop now.
+ recycleBinEmpty = false;
+ recycleBinEmptySet = true;
+ break;
+ }
+ }
+
  FIXME("stub\n");
 
  return S_OK;