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"""Module with functions which are supposed to be as fast as possible""" from stat import S_ISDIR from git.compat import ( byte_ord, safe_decode, defenc, xrange, text_type, bchr ) __all__ = ('tree_to_stream', 'tree_entries_from_data', 'traverse_trees_recursive', 'traverse_tree_recursive') def tree_to_stream(entries, write): """Write the give list of entries into a stream using its write method :param entries: **sorted** list of tuples with (binsha, mode, name) :param write: write method which takes a data string""" ord_zero = ord('0') bit_mask = 7 # 3 bits set for binsha, mode, name in entries: mode_str = b'' for i in xrange(6): mode_str = bchr(((mode >> (i * 3)) & bit_mask) + ord_zero) + mode_str # END for each 8 octal value # git slices away the first octal if its zero if byte_ord(mode_str[0]) == ord_zero: mode_str = mode_str[1:] # END save a byte # here it comes: if the name is actually unicode, the replacement below # will not work as the binsha is not part of the ascii unicode encoding - # hence we must convert to an utf8 string for it to work properly. # According to my tests, this is exactly what git does, that is it just # takes the input literally, which appears to be utf8 on linux. if isinstance(name, text_type): name = name.encode(defenc) write(b''.join((mode_str, b' ', name, b'\0', binsha))) # END for each item def tree_entries_from_data(data): """Reads the binary representation of a tree and returns tuples of Tree items :param data: data block with tree data (as bytes) :return: list(tuple(binsha, mode, tree_relative_path), ...)""" ord_zero = ord('0') space_ord = ord(' ') len_data = len(data) i = 0 out = [] while i < len_data: mode = 0 # read mode # Some git versions truncate the leading 0, some don't # The type will be extracted from the mode later while byte_ord(data[i]) != space_ord: # move existing mode integer up one level being 3 bits # and add the actual ordinal value of the character mode = (mode