// This function walks all watched files, collects changes, and updates state
private FileChangeList ComputeChangesAndUpdateState()
{
_version++;
var changes = new FileChangeList();
WIN32_FIND_DATAW fileData = new WIN32_FIND_DATAW();
unsafe
{
WIN32_FIND_DATAW* pFileData = &fileData;
for(int index=0; index < _directories.Count; index++) {
var directory = _directories[index];
var handle = DllImports.FindFirstFileExW(directory, FINDEX_INFO_LEVELS.FindExInfoBasic, pFileData, FINDEX_SEARCH_OPS.FindExSearchNameMatch, IntPtr.Zero, DllImports.FIND_FIRST_EX_LARGE_FETCH);
if (handle == DllImports.INVALID_HANDLE_VALUE) { // directory got deleted
if (Tracing.Switch.ShouldTrace(TraceEventType.Information))
{
Tracing.TraceEvent(TraceEventType.Warning, 2, "Directory could not be opened {0}", directory);
}
_directories.Remove(directory);
continue;
}
try
{
do
{
if (IsSpecial(fileData.cFileName)) continue;
if (!IsWatched(fileData.cFileName)) continue;
UpdateState(directory, ref changes, ref fileData, fileData.cFileName);
}
while (DllImports.FindNextFileW(handle, pFileData));
}
finally
{
DllImports.FindClose(handle);
}
}
}
foreach (var value in _state) {
if (value._version != _version) {
changes.AddRemoved(value.Directory, value.Path);
_state.Remove(value.Directory, value.Path);
}
}
return changes;
}
private unsafe void UpdateState(string directory, ref FileChangeList changes, ref WIN32_FIND_DATAW file, char* filename)
{
int index = _state.IndexOf(directory, filename);
if (index == -1) // file added
{
string path = new string(filename);
if (file.IsDirectory) {
if (_includeSubdirectories) {
_directories.Add(Path.Combine(directory.TrimEnd('*'), path, "*"));
}
}
changes.AddAdded(directory, path);
var newFileState = new FileState(directory, path);
newFileState.LastWrite = file.LastWrite;
newFileState.FileSize = file.FileSize;
newFileState._version = _version;
_state.Add(directory, path, newFileState);
return;
}
_state.Values[index]._version = _version;
if (file.IsDirectory) {
return;
}
var previousState = _state.Values[index];
if (file.LastWrite != previousState.LastWrite || file.FileSize != previousState.FileSize) {
changes.AddChanged(directory, previousState.Path);
_state.Values[index].LastWrite = file.LastWrite;
_state.Values[index].FileSize = file.FileSize;
}
}
