Skip to content

refactor: update bitarray directly instead of building a string first #180

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
M0r13n wants to merge 1 commit into from
Closed

refactor: update bitarray directly instead of building a string first #180

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 14 additions & 6 deletions pyais/util.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -29,9 +29,9 @@ def decode_into_bit_array(data: bytes, fill_bits: int = 0) -> bitarray:
:param fill_bits: Number of trailing fill bits to be ignored
:return:
"""
bit_str = ''
length = len(data)

bits = bitarray(len(data) * 6 - fill_bits)
bit_pos = 0
for i, c in enumerate(data):
if not 0x20 <= c <= 0x7e:
raise NonPrintableCharacterException(f"Non printable character: '{hex(c)}'")
Expand All @@ -43,12 +43,20 @@ def decode_into_bit_array(data: bytes, fill_bits: int = 0) -> bitarray:
if i == length - 1 and fill_bits:
# The last part be shorter than 6 bits and contain fill bits
c = c >> fill_bits
bit_str += f'{c:b}'.zfill(6 - fill_bits)
bits_to_write = 6 - fill_bits
for bit_idx in range(bits_to_write - 1, -1, -1):
bits[bit_pos] = (c & (1 << bit_idx)) > 0
bit_pos += 1
else:
bit_str += f'{c:06b}'
bits[bit_pos] = (c & (1 << 5)) > 0
bits[bit_pos + 1] = (c & (1 << 4)) > 0
bits[bit_pos + 2] = (c & (1 << 3)) > 0
bits[bit_pos + 3] = (c & (1 << 2)) > 0
bits[bit_pos + 4] = (c & (1 << 1)) > 0
bits[bit_pos + 5] = (c & 1) > 0
bit_pos += 6

bit_arr = bitarray(bit_str)
return bit_arr
return bits


def chunks(sequence: typing.Sequence[T], n: int) -> Generator[typing.Sequence[T], None, None]:
Expand Down