Method _Open

source/TextIO.cpp:592–661

TextFile

// TextFile
//
bool TextFile::_Open(LPCTSTR aFileSpec, DWORD &aFlags)
{
	_Close();
	DWORD dwDesiredAccess, dwShareMode, dwCreationDisposition;
	switch (aFlags & ACCESS_MODE_MASK) {
		case READ:
			dwDesiredAccess = GENERIC_READ;
			dwCreationDisposition = OPEN_EXISTING;
			break;
		case WRITE:
			dwDesiredAccess = GENERIC_WRITE;
			dwCreationDisposition = CREATE_ALWAYS;
			break;
		case APPEND:
		case UPDATE:
			dwDesiredAccess = GENERIC_WRITE | GENERIC_READ;
			dwCreationDisposition = OPEN_ALWAYS;
			break;
		case USEHANDLE:
			if (!GetFileType((HANDLE)aFileSpec))
				return false;
			mFile = (HANDLE)aFileSpec;
			return true;
	}
	dwShareMode = ((aFlags >> 8) & (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE));

	if (*aFileSpec == '*')
	{
		// v1.1.17: Allow FileOpen("*", "r|w") to open stdin/stdout/stderr ("**" for stderr).
		// Can also be used to read script text from stdin, by passing "*" as the filename.
		DWORD nStdHandle = 0;
		switch (aFlags & ACCESS_MODE_MASK)
		{
		case APPEND:
			// Allow FileAppend to write to stdout/stderr via TextStream.
			aFlags = (aFlags & ~ACCESS_MODE_MASK) | READ;
		case WRITE:
			if (!aFileSpec[1])
				nStdHandle = STD_OUTPUT_HANDLE;
			else if (aFileSpec[1] == '*' && !aFileSpec[2])
				nStdHandle = STD_ERROR_HANDLE;
			break;
		case READ:
			if (!aFileSpec[1])
				nStdHandle = STD_INPUT_HANDLE;
			break;
		}
		if (nStdHandle) // It was * or ** and not something invalid like *Somefile.
		{
			HANDLE hstd = GetStdHandle(nStdHandle);
			if (hstd == NULL)// || !DuplicateHandle(GetCurrentProcess(), hstd, GetCurrentProcess(), &hstd, 0, FALSE, DUPLICATE_SAME_ACCESS))
			{
				SetLastError(ERROR_INVALID_HANDLE); // Avoid "The operation completed successfully".
				return false;
			}
			aFlags = (aFlags & ~ACCESS_MODE_MASK) | USEHANDLE; // Avoid calling CloseHandle(), since we don't own it.
			mFile = hstd; // Only now that we know it's not NULL.
			return true;