Function DoesFilePatternExist

source/util.cpp:1454–1496

bool DoesFilePatternExist(LPTSTR aFilePattern, DWORD *aFileAttr, DWORD aRequiredAttr)
// Returns true if the file/folder exists or false otherwise.
// If non-NULL, aFileAttr's DWORD is set to the attributes of the file/folder if a match is found.
// If there is no match, its contents are undefined.
{
	if (!aFilePattern || !*aFilePattern) return false;
	// Fix for v1.0.35.12: Don't consider the question mark in "\\?\Volume{GUID}\" to be a wildcard.
	// Such volume names are obtained from GetVolumeNameForVolumeMountPoint() and perhaps other functions.
	// However, testing shows that wildcards beyond that first one should be seen as real wildcards
	// because the wildcard match-method below does work for such volume names.
	LPTSTR cp = _tcsncmp(aFilePattern, _T("\\\\?\\"), 4) ? aFilePattern : aFilePattern + 4;
	if (StrChrAny(cp, _T("?*")))
	{
		WIN32_FIND_DATA wfd;
		HANDLE hFile = FindFirstFile(aFilePattern, &wfd);
		if (hFile == INVALID_HANDLE_VALUE)
			return false;
		// Skip . and .., which appear to always be listed first (for dir\* and dir\*.*).
		while (wfd.cFileName[0] == '.' && (!wfd.cFileName[1] || wfd.cFileName[1] == '.' && !wfd.cFileName[2]))
			if (!FindNextFile(hFile, &wfd))
				return false;
		if (aRequiredAttr) // Caller wants to check for a file/folder with specific attributes.
		{
			while ((wfd.dwFileAttributes & aRequiredAttr) != aRequiredAttr)
				if (!FindNextFile(hFile, &wfd))
					return false;
			// Since above didn't return, a file/folder with the required attribute was found.
		}
		FindClose(hFile);
		if (aFileAttr)
			*aFileAttr = wfd.dwFileAttributes;
		return true;
	}
    else
	{
		DWORD attr = GetFileAttributes(aFilePattern);
		if (aRequiredAttr && (attr & aRequiredAttr) != aRequiredAttr)
			return false;
		if (aFileAttr)
			*aFileAttr = attr;
		return attr != 0xFFFFFFFF;
	}
}