Method PerformLoopReadFile

source/script.cpp:11579–11636

ResultType Line::PerformLoopReadFile(ResultToken *aResultToken, Line *&aJumpToLine, Line *aUntil
	, LPTSTR aReadFileName, LPTSTR aWriteFileName)
{
	TextFile tfile;
	bool file_is_open = tfile.Open(aReadFileName, DEFAULT_READ_FLAGS, g->Encoding & CP_AHKCP);
	if (!file_is_open)
	{
		// Failed to open the input file.  If an ELSE is present, executing it if the file wasn't found
		// seems much more useful than executing ELSE only for empty files; but if there's no ELSE, it's
		// probably best to throw an error.
		DWORD error = GetLastError();
		if (  !(mRelatedLine->mActionType == ACT_ELSE && (error == ERROR_FILE_NOT_FOUND || error == ERROR_PATH_NOT_FOUND))  )
			return g_script.Win32Error(error);
		// Otherwise, execute the ELSE below.
	}

	// Make a persistent copy in case aWriteFileName's contents are in the deref buffer:
	if (  !(aWriteFileName = _tcsdup(aWriteFileName))  )
		return MemoryError();

	LoopReadFileStruct loop_info { aWriteFileName };
	size_t line_length;
	ResultType result = CONDITION_FALSE;
	Line *jump_to_line = nullptr;
	global_struct &g = *::g; // Primarily for performance in this case.
	g.mLoopReadFile = &loop_info;

	if (file_is_open)
	for (;; ++g.mLoopIteration)
	{ 
		if (  !(line_length = tfile.ReadLine(loop_info.mCurrentLine, _countof(loop_info.mCurrentLine) - 1))  ) // -1 to ensure there's room for a null-terminator.
			break;
		if (loop_info.mCurrentLine[line_length - 1] == '\n') // Remove end-of-line character.
			--line_length;
		loop_info.mCurrentLine[line_length] = '\0';

		PERFORMLOOP_EXECUTE_BODY
		PERFORMLOOP_EVALUATE_UNTIL
	}

	if (result == CONDITION_FALSE)
	{
		// No lines were read, so execute this loop's ELSE if present.  It's done here rather than
		// in ExecUntil so that FileAppend can be used within the ELSE to write to mWriteFile.
		if (mRelatedLine->mActionType == ACT_ELSE)
			result = mRelatedLine->mNextLine->ExecUntil(ONLY_ONE_LINE, aResultToken, &aJumpToLine);
		else
			result = OK; // Never return CONDITION_FALSE, otherwise ExecUntil() will execute the ELSE a second time.
	}

	if (loop_info.mWriteFile)
	{
		loop_info.mWriteFile->Close();
		delete loop_info.mWriteFile;
	}

	return result;
}