Implement binhex protocol.
Note: binhex works, hexbin does not work yet.
This commit is contained in:
Jack Jansen
parent
cf6369394e
commit
fcdffeaaa1
|
|
@ -0,0 +1,485 @@
|
|||
"""binhex - Macintosh binhex compression/decompression
|
||||
easy interface:
|
||||
binhex(inputfilename, outputfilename)
|
||||
hexbin(inputfilename, outputfilename)
|
||||
"""
|
||||
|
||||
#
|
||||
# Jack Jansen, CWI, August 1995.
|
||||
#
|
||||
# The module is supposed to be as compatible as possible. Especially the
|
||||
# easy interface should work "as expected" on any platform.
|
||||
# XXXX Note: currently, textfiles appear in mac-form on all platforms.
|
||||
# We seem to lack a simple character-translate in python.
|
||||
# (we should probably use ISO-Latin-1 on all but the mac platform).
|
||||
# XXXX The simeple routines are too simple: they expect to hold the complete
|
||||
# files in-core. Should be fixed.
|
||||
# XXXX It would be nice to handle AppleDouble format on unix (for servers serving
|
||||
# macs).
|
||||
# XXXX I don't understand what happens when you get 0x90 times the same byte on
|
||||
# input. The resulting code (xx 90 90) would appear to be interpreted as an
|
||||
# escaped *value* of 0x90. All coders I've seen appear to ignore this nicety...
|
||||
#
|
||||
import sys
|
||||
import os
|
||||
import struct
|
||||
import string
|
||||
import binascii
|
||||
|
||||
DEBUG=1
|
||||
|
||||
testf = open('@xx', 'w') # XXXX
|
||||
|
||||
Error = 'binhex.Error'
|
||||
|
||||
# States (what have we written)
|
||||
[_DID_HEADER, _DID_DATA, _DID_RSRC] = range(3)
|
||||
|
||||
# Various constants
|
||||
REASONABLY_LARGE=32768 # Minimal amount we pass the rle-coder
|
||||
LINELEN=48 # What we pass to hqx-coder at once
|
||||
# *NOTE* Must be divisible by 3!
|
||||
RUNCHAR=chr(0x90) # run-length introducer
|
||||
|
||||
#
|
||||
# The code is currently byte-order dependent
|
||||
if struct.pack('i', 0177) != '\0\0\0\177':
|
||||
raise ImportError, 'Module binhex is big-endian only'
|
||||
|
||||
#
|
||||
# Workarounds for non-mac machines.
|
||||
if os.name == 'mac':
|
||||
import macfs
|
||||
|
||||
def FInfo():
|
||||
return macfs.FInfo()
|
||||
|
||||
def getfileinfo(name):
|
||||
finfo = macfs.FSSpec(name).GetFInfo()
|
||||
dir, file = os.path.split(name)
|
||||
# XXXX Get resource/data sizes
|
||||
fp = open(name, 'rb')
|
||||
fp.seek(0, 2)
|
||||
dlen = fp.tell()
|
||||
fp = open(name, '*rb')
|
||||
fp.seek(0, 2)
|
||||
rlen = fp.tell()
|
||||
return file, finfo, dlen, rlen
|
||||
|
||||
def openrsrc(name, *mode):
|
||||
if mode:
|
||||
mode = mode[0]
|
||||
else:
|
||||
mode = 'rb'
|
||||
mode = '*' + mode
|
||||
return open(name, mode)
|
||||
|
||||
else:
|
||||
#
|
||||
# Glue code for non-macintosh useage
|
||||
#
|
||||
import regsub
|
||||
|
||||
class FInfo:
|
||||
def __init__(self):
|
||||
self.Type = '????'
|
||||
self.Creator = '????'
|
||||
self.Flags = 0
|
||||
|
||||
def getfileinfo(name):
|
||||
finfo = FInfo()
|
||||
# Quick check for textfile
|
||||
fp = open(name)
|
||||
data = open(name).read(256)
|
||||
for c in data:
|
||||
if not c in string.whitespace and (c<' ' or ord(c) > 0177):
|
||||
break
|
||||
else:
|
||||
finfo.Type = 'TEXT'
|
||||
fp.seek(0, 2)
|
||||
dsize = fp.tell()
|
||||
fp.close()
|
||||
dir, file = os.path.split(name)
|
||||
file = regsub.sub(':', '-', file)
|
||||
return file, finfo, dsize, 0
|
||||
|
||||
class openrsrc:
|
||||
def __init__(self, *args):
|
||||
pass
|
||||
|
||||
def read(self, *args):
|
||||
return ''
|
||||
|
||||
def write(self, *args):
|
||||
pass
|
||||
|
||||
def close(self):
|
||||
pass
|
||||
|
||||
class _Hqxcoderengine:
|
||||
"""Write data to the coder in 3-byte chunks"""
|
||||
|
||||
def __init__(self, ofp):
|
||||
self.ofp = ofp
|
||||
self.data = ''
|
||||
|
||||
def write(self, data):
|
||||
self.data = self.data + data
|
||||
while len(self.data) > LINELEN:
|
||||
hqxdata = binascii.b2a_hqx(self.data[:LINELEN])
|
||||
self.ofp.write(hqxdata+'\n')
|
||||
self.data = self.data[LINELEN:]
|
||||
|
||||
def close(self):
|
||||
if self.data:
|
||||
self.ofp.write(binascii.b2a_hqx(self.data))
|
||||
self.ofp.write(':\n')
|
||||
self.ofp.close()
|
||||
|
||||
class _Rlecoderengine:
|
||||
"""Write data to the RLE-coder in suitably large chunks"""
|
||||
|
||||
def __init__(self, ofp):
|
||||
self.ofp = ofp
|
||||
self.data = ''
|
||||
|
||||
def write(self, data):
|
||||
testf.write(data) # XXXX
|
||||
self.data = self.data + data
|
||||
if len(self.data) < REASONABLY_LARGE:
|
||||
return
|
||||
rledata = binascii.rlecode_hqx(self.data)
|
||||
self.ofp.write(rledata)
|
||||
self.data = ''
|
||||
|
||||
def close(self):
|
||||
if self.data:
|
||||
rledata = binascii.rlecode_hqx(self.data)
|
||||
self.ofp.write(rledata)
|
||||
self.ofp.close()
|
||||
|
||||
class BinHex:
|
||||
def __init__(self, (name, finfo, dlen, rlen), ofp):
|
||||
if type(ofp) == type(''):
|
||||
ofname = ofp
|
||||
ofp = open(ofname, 'w')
|
||||
if os.name == 'mac':
|
||||
fss = macfs.FSSpec(ofname)
|
||||
fss.SetCreatorType('BnHq', 'TEXT')
|
||||
ofp.write('(This file may be decompressed with BinHex 4.0)\n\n:')
|
||||
hqxer = _Hqxcoderengine(ofp)
|
||||
self.ofp = _Rlecoderengine(hqxer)
|
||||
self.crc = 0
|
||||
if finfo == None:
|
||||
finfo = FInfo()
|
||||
self.dlen = dlen
|
||||
self.rlen = rlen
|
||||
self._writeinfo(name, finfo)
|
||||
self.state = _DID_HEADER
|
||||
|
||||
def _writeinfo(self, name, finfo):
|
||||
if DEBUG:
|
||||
print 'binhex info:', name, finfo.Type, finfo.Creator, self.dlen, self.rlen
|
||||
name = name
|
||||
nl = len(name)
|
||||
if nl > 63:
|
||||
raise Error, 'Filename too long'
|
||||
d = chr(nl) + name + '\0'
|
||||
d2 = finfo.Type + finfo.Creator
|
||||
d3 = struct.pack('h', finfo.Flags)
|
||||
d4 = struct.pack('ii', self.dlen, self.rlen)
|
||||
info = d + d2 + d3 + d4
|
||||
self._write(info)
|
||||
self._writecrc()
|
||||
|
||||
def _write(self, data):
|
||||
self.crc = binascii.crc_hqx(data, self.crc)
|
||||
self.ofp.write(data)
|
||||
|
||||
def _writecrc(self):
|
||||
self.ofp.write(struct.pack('h', self.crc))
|
||||
self.crc = 0
|
||||
|
||||
def write(self, data):
|
||||
if self.state != _DID_HEADER:
|
||||
raise Error, 'Writing data at the wrong time'
|
||||
self.dlen = self.dlen - len(data)
|
||||
self._write(data)
|
||||
|
||||
def close_data(self):
|
||||
if self.dlen <> 0:
|
||||
raise Error, 'Incorrect data size, diff='+`self.rlen`
|
||||
self._writecrc()
|
||||
self.state = _DID_DATA
|
||||
|
||||
def write_rsrc(self, data):
|
||||
if self.state < _DID_DATA:
|
||||
self.close_data()
|
||||
if self.state != _DID_DATA:
|
||||
raise Error, 'Writing resource data at the wrong time'
|
||||
self.rlen = self.rlen - len(data)
|
||||
self._write(data)
|
||||
|
||||
def close(self):
|
||||
if self.state < _DID_DATA:
|
||||
self.close_data()
|
||||
if self.state != _DID_DATA:
|
||||
raise Error, 'Close at the wrong time'
|
||||
if self.rlen <> 0:
|
||||
raise Error, "Incorrect resource-datasize, diff="+`self.rlen`
|
||||
self._writecrc()
|
||||
self.ofp.close()
|
||||
self.state = None
|
||||
|
||||
def binhex(inp, out):
|
||||
"""(infilename, outfilename) - Create binhex-encoded copy of a file"""
|
||||
finfo = getfileinfo(inp)
|
||||
ofp = BinHex(finfo, out)
|
||||
|
||||
ifp = open(inp, 'rb')
|
||||
# XXXX Do textfile translation on non-mac systems
|
||||
d = ifp.read()
|
||||
ofp.write(d)
|
||||
ofp.close_data()
|
||||
ifp.close()
|
||||
|
||||
ifp = openrsrc(inp, 'rb')
|
||||
d = ifp.read()
|
||||
ofp.write_rsrc(d)
|
||||
ofp.close()
|
||||
ifp.close()
|
||||
|
||||
class _Hqxdecoderengine:
|
||||
"""Read data via the decoder in 4-byte chunks"""
|
||||
|
||||
def __init__(self, ifp):
|
||||
self.ifp = ifp
|
||||
self.eof = 0
|
||||
|
||||
def read(self, wtd):
|
||||
"""Read at least wtd bytes (or until EOF)"""
|
||||
decdata = ''
|
||||
#
|
||||
# The loop here is convoluted, since we don't really now how much
|
||||
# to decode: there may be newlines in the incoming data.
|
||||
while wtd > 0:
|
||||
if self.eof: return decdata
|
||||
wtd = ((wtd+2)/3)*4
|
||||
data = self.ifp.read(wtd)
|
||||
#
|
||||
# Next problem: there may not be a complete number of bytes in what we
|
||||
# pass to a2b. Solve by yet another loop.
|
||||
#
|
||||
while 1:
|
||||
try:
|
||||
decdatacur, self.eof = binascii.a2b_hqx(data)
|
||||
if self.eof: print 'EOF'
|
||||
break
|
||||
except binascii.Incomplete:
|
||||
pass
|
||||
newdata = self.ifp.read(1)
|
||||
if not newdata:
|
||||
raise Error, 'Premature EOF on binhex file'
|
||||
data = data + newdata
|
||||
decdata = decdata + decdatacur
|
||||
wtd = wtd - len(decdata)
|
||||
if not decdata and not self.eof:
|
||||
raise Error, 'Premature EOF on binhex file'
|
||||
return decdata
|
||||
|
||||
def close(self):
|
||||
self.ifp.close()
|
||||
|
||||
class _Rledecoderengine:
|
||||
"""Read data via the RLE-coder"""
|
||||
|
||||
def __init__(self, ifp):
|
||||
self.ifp = ifp
|
||||
self.pre_buffer = ''
|
||||
self.post_buffer = ''
|
||||
self.eof = 0
|
||||
|
||||
def read(self, wtd):
|
||||
if wtd > len(self.post_buffer):
|
||||
self._fill(wtd-len(self.post_buffer))
|
||||
rv = self.post_buffer[:wtd]
|
||||
self.post_buffer = self.post_buffer[wtd:]
|
||||
print 'WTD', wtd, 'GOT', len(rv)
|
||||
return rv
|
||||
|
||||
def _fill(self, wtd):
|
||||
#
|
||||
# Obfuscated code ahead. We keep at least one byte in the pre_buffer,
|
||||
# so we don't stumble over an orphaned RUNCHAR later on. If the
|
||||
# last or second-last char is a RUNCHAR we keep more bytes.
|
||||
#
|
||||
self.pre_buffer = self.pre_buffer + self.ifp.read(wtd+2)
|
||||
if self.ifp.eof:
|
||||
self.post_buffer = self.post_buffer + \
|
||||
binascii.rledecode_hqx(self.pre_buffer)
|
||||
self.pre_buffer = ''
|
||||
return
|
||||
|
||||
lastrle = string.rfind(self.pre_buffer, RUNCHAR)
|
||||
if lastrle > 0 and lastrle == len(self.pre_buffer)-1:
|
||||
# Last byte is an RLE, keep two bytes
|
||||
mark = len(self.pre_buffer)-2
|
||||
elif lastrle > 0 and lastrle == len(self.pre_buffer)-2:
|
||||
# second-last byte is an RLE. Decode all.
|
||||
mark = len(self.pre_buffer)
|
||||
else:
|
||||
mark = len(self.pre_buffer)-1
|
||||
self.post_buffer = self.post_buffer + \
|
||||
binascii.rledecode_hqx(self.pre_buffer[:mark])
|
||||
self.pre_buffer = self.pre_buffer[mark:]
|
||||
|
||||
def close(self):
|
||||
self.ifp.close()
|
||||
|
||||
class HexBin:
|
||||
def __init__(self, ifp):
|
||||
if type(ifp) == type(''):
|
||||
ifp = open(ifp)
|
||||
#
|
||||
# Find initial colon.
|
||||
#
|
||||
while 1:
|
||||
ch = ifp.read(1)
|
||||
if not ch:
|
||||
raise Error, "No binhex data found"
|
||||
if ch == ':':
|
||||
break
|
||||
if ch != '\n':
|
||||
dummy = ifp.readline()
|
||||
if DEBUG:
|
||||
print 'SKIP:', ch+dummy
|
||||
|
||||
hqxifp = _Hqxdecoderengine(ifp)
|
||||
self.ifp = _Rledecoderengine(hqxifp)
|
||||
self.crc = 0
|
||||
self._readheader()
|
||||
|
||||
def _read(self, len):
|
||||
data = self.ifp.read(len)
|
||||
self.crc = binascii.crc_hqx(data, self.crc)
|
||||
return data
|
||||
|
||||
def _checkcrc(self):
|
||||
filecrc = struct.unpack('h', self.ifp.read(2))[0] & 0xffff
|
||||
self.crc = self.crc & 0xffff
|
||||
if DEBUG:
|
||||
print 'DBG CRC %x %x'%(self.crc, filecrc)
|
||||
#if filecrc != self.crc:
|
||||
# raise Error, 'CRC error, computed %x, read %x'%(self.crc, filecrc)
|
||||
self.crc = 0
|
||||
|
||||
def _readheader(self):
|
||||
len = self._read(1)
|
||||
fname = self._read(ord(len))
|
||||
rest = self._read(1+4+4+2+4+4)
|
||||
self._checkcrc()
|
||||
|
||||
type = rest[1:5]
|
||||
creator = rest[5:9]
|
||||
flags = struct.unpack('h', rest[9:11])[0]
|
||||
self.dlen = struct.unpack('l', rest[11:15])[0]
|
||||
self.rlen = struct.unpack('l', rest[15:19])[0]
|
||||
|
||||
if DEBUG:
|
||||
print 'DATA, RLEN', self.dlen, self.rlen
|
||||
|
||||
self.FName = fname
|
||||
self.FInfo = FInfo()
|
||||
self.FInfo.Creator = creator
|
||||
self.FInfo.Type = type
|
||||
self.FInfo.Flags = flags
|
||||
|
||||
self.state = _DID_HEADER
|
||||
|
||||
def read(self, *n):
|
||||
if self.state != _DID_HEADER:
|
||||
raise Error, 'Read data at wrong time'
|
||||
if n:
|
||||
n = n[0]
|
||||
n = min(n, self.dlen)
|
||||
else:
|
||||
n = self.dlen
|
||||
self.dlen = self.dlen - n
|
||||
return self._read(n)
|
||||
|
||||
def close_data(self):
|
||||
if self.state != _DID_HEADER:
|
||||
raise Error, 'close_data at wrong time'
|
||||
if self.dlen:
|
||||
dummy = self._read(self.dlen)
|
||||
self._checkcrc()
|
||||
self.state = _DID_DATA
|
||||
|
||||
def read_rsrc(self, *n):
|
||||
if self.state == _DID_HEADER:
|
||||
self.close_data()
|
||||
if self.state != _DID_DATA:
|
||||
raise Error, 'Read resource data at wrong time'
|
||||
if n:
|
||||
n = n[0]
|
||||
n = min(n, self.rlen)
|
||||
else:
|
||||
n = self.rlen
|
||||
self.rlen = self.rlen - n
|
||||
return self._read(n)
|
||||
|
||||
def close(self):
|
||||
if self.rlen:
|
||||
dummy = self.read_rsrc(self.rlen)
|
||||
self._checkcrc()
|
||||
self.state = _DID_RSRC
|
||||
self.ifp.close()
|
||||
|
||||
def hexbin(inp, out):
|
||||
"""(infilename, outfilename) - Decode binhexed file"""
|
||||
ifp = HexBin(inp)
|
||||
finfo = ifp.FInfo
|
||||
if not out:
|
||||
out = ifp.FName
|
||||
if os.name == 'mac':
|
||||
ofss = macfs.FSSpec(out)
|
||||
out = ofss.as_pathname()
|
||||
|
||||
ofp = open(out, 'wb')
|
||||
# XXXX Do translation on non-mac systems
|
||||
d = ifp.read()
|
||||
ofp.write(d)
|
||||
ofp.close()
|
||||
ifp.close_data()
|
||||
|
||||
d = ifp.read_rsrc()
|
||||
if d:
|
||||
ofp = openrsrc(out, 'wb')
|
||||
ofp.write(d)
|
||||
ofp.close()
|
||||
|
||||
if os.name == 'mac':
|
||||
nfinfo = ofss.GetFInfo()
|
||||
nfinfo.Creator = finfo.Creator
|
||||
nfinfo.Type = finfo.Type
|
||||
nfinfo.Flags = finfo.Flags
|
||||
ofss.SetFInfo(nfinfo)
|
||||
|
||||
ifp.close()
|
||||
|
||||
def _test():
|
||||
if os.name == 'mac':
|
||||
fss, ok = macfs.StandardGetFile()
|
||||
if not ok:
|
||||
sys.exit(0)
|
||||
fname = fss.as_pathname()
|
||||
else:
|
||||
fname = sys.argv[1]
|
||||
#binhex(fname, fname+'.hqx')
|
||||
#hexbin(fname+'.hqx', fname+'.viahqx')
|
||||
hexbin(fname, fname+'.unpacked')
|
||||
sys.exit(1)
|
||||
|
||||
if __name__ == '__main__':
|
||||
_test()
|
||||
|
||||
Loading…
Reference in New Issue