gecko-dev/js/xpconnect/loader/script_cache.py

82 строки
2.0 KiB
Python
Executable File

#!/usr/bin/env python
import io
import os
import struct
import sys
MAGIC = b'mozXDRcachev001\0'
def usage():
print("""Usage: script_cache.py <file.bin> ...
Decodes and prints out the contents of a startup script cache file
(e.g., startupCache/scriptCache.bin) in human-readable form.""")
sys.exit(1)
class ProcessTypes:
Default = 0
Web = 1
Extension = 2
def __init__(self, val):
self.val = val
def __str__(self):
res = []
if self.val & (1 << self.Default):
res.append('Parent')
if self.val & (1 << self.Web):
res.append('Web')
if self.val & (1 << self.Extension):
res.append('Extension')
return '|'.join(res)
class InputBuffer(object):
def __init__(self, data):
self.data = data
self.offset = 0
@property
def remaining(self):
return len(self.data) - self.offset
def unpack(self, fmt):
res = struct.unpack_from(fmt, self.data, self.offset)
self.offset += struct.calcsize(fmt)
return res
def unpack_str(self):
size, = self.unpack('<H')
res = self.data[self.offset:self.offset + size].decode('utf-8')
self.offset += size
return res
if len(sys.argv) < 2 or not os.path.exists(sys.argv[1]):
usage()
for filename in sys.argv[1:]:
with io.open(filename, 'rb') as f:
magic = f.read(len(MAGIC))
if magic != MAGIC:
raise Exception('Bad magic number')
hdrSize, = struct.unpack('<I', f.read(4))
hdr = InputBuffer(f.read(hdrSize))
i = 0
while hdr.remaining:
i += 1
print('{}: {}'.format(i, hdr.unpack_str()))
print(' Key: {}'.format(hdr.unpack_str()))
print(' Offset: {:>9,}'.format(*hdr.unpack('<I')))
print(' Size: {:>9,}'.format(*hdr.unpack('<I')))
print(' Processes: {}'.format(ProcessTypes(*hdr.unpack('B'))))
print('')