Onionr/src/utils/reconstructhash.py

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'''
Onionr - Private P2P Communication
z-fill (zero fill) a string to a specific length
intended for reconstructing block hashes
'''
from typing import Union
'''
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
'''
def reconstruct_hash(hex_hash: Union[str, bytes],
length: int = 64) -> Union[str, bytes]:
"""Pad hash hex string with zeros, return result"""
return hex_hash.zfill(length)
def deconstruct_hash(hex_hash: Union[str, bytes]) -> Union[str, bytes]:
"""Remove leading zeros from hex hash, return result"""
new_hash = ''
ret_bytes = False
try:
hex_hash = hex_hash.decode()
ret_bytes = True
except AttributeError:
pass
c = 0
for x in hex_hash:
if x == '0':
c += 1
else:
break
new_hash = hex_hash[c:]
if ret_bytes:
new_hash = new_hash.encode()
return new_hash