Gadgetbridge/external/pack.py

125 lines
4.0 KiB
Python

# File downloaded from https://github.com/dakhnod/Fossil-HR-SDK/
import sys
import os
import json
import crc32c
import getopt
class Packer:
def __init__(self):
self.file_block = bytearray()
def put_int(self, content, length=4):
self.file_block.extend(content.to_bytes(length, 'little'))
def pack(self, input_dir_path, output_file_path):
start_path = os.getcwd()
if not os.path.isdir(input_dir_path):
print('cannot find dir %s' % input_dir_path)
exit()
os.chdir(input_dir_path)
with open('app.json', 'r') as json_file:
app_meta = json.load(json_file)
os.chdir('files')
all_files = []
dir_sizes = {}
for files_dir_list in [('code', False), ('icons', False), ('layout', True), ('display_name', True), ('config', True)]:
dir_size = 0
files_dir = files_dir_list[0]
append_null = files_dir_list[1]
files = os.listdir(files_dir)
os.chdir(files_dir)
for file in sorted(files):
print(f'packing {file}')
with open(file, 'rb')as f:
contents = bytearray(f.read())
if append_null:
contents.append(0)
file_size = contents.__len__()
all_files.append({
'filename': file,
'contents': contents,
'size': file_size
})
dir_size = dir_size + file_size + file.__len__() + 4 # null byte + size bytes
os.chdir(os.pardir)
dir_sizes[files_dir] = dir_size
offset_code = 88
offset_icons = offset_code + dir_sizes['code']
offset_layout = offset_icons + dir_sizes['icons']
offset_display_name = offset_layout + dir_sizes['layout']
offset_config = offset_display_name + dir_sizes['display_name']
offset_file_end = offset_config + dir_sizes['config']
self.file_block.extend([int(octet) for octet in app_meta['version'].split('.')])
self.put_int(0)
self.put_int(0)
self.put_int(offset_code)
self.put_int(offset_icons)
self.put_int(offset_layout)
self.put_int(offset_display_name)
self.put_int(offset_display_name)
self.put_int(offset_config)
self.put_int(offset_file_end)
self.put_int(0)
self.put_int(0)
self.put_int(0)
self.put_int(0)
self.put_int(0)
self.put_int(0)
self.put_int(0)
self.put_int(0)
self.put_int(0)
for file in all_files:
filename = file['filename']
self.put_int(filename.__len__() + 1, 1)
self.file_block.extend(filename.encode('utf-8'))
self.put_int(0, 1) # null byte ending
self.put_int(file['size'], 2)
self.file_block.extend(file['contents'])
os.chdir(start_path)
identifier = all_files[0]['filename']
full_file = bytearray()
full_file.extend([0xFE, 0x15]) # file handle
full_file.extend([0x03, 0x00]) # file version
full_file.extend(int(0).to_bytes(4, 'little')) # file offset
full_file.extend(self.file_block.__len__().to_bytes(4, 'little')) # file size
full_file.extend(self.file_block)
full_file.extend(crc32c.crc32c(self.file_block).to_bytes(4, 'little'))
if output_file_path is None:
output_file_path = identifier
with open(output_file_path, 'wb') as output_file:
output_file.write(full_file)
def main():
packer = Packer()
input_dir_path = None
output_file_path = None
args, remainder = getopt.getopt(sys.argv[1:], 'i:o:', ['input=', 'output='])
for key, value in args:
if key in ['-i', '--input']:
input_dir_path = value
elif key in ['-o', '--output']:
output_file_path = value
packer.pack(input_dir_path, output_file_path)
if __name__ == '__main__':
main()