home *** CD-ROM | disk | FTP | other *** search
- """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
-
- 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=64
- RUNCHAR=chr(0x90) # run-length introducer
-
- #
- # This code is no longer byte-order dependent
-
- #
- # Workarounds for non-mac machines.
- if os.name == 'mac':
- import macfs
- import MacOS
- try:
- openrf = MacOS.openrf
- except AttributeError:
- # Backward compatability
- openrf = open
-
- 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 = openrf(name, '*rb')
- fp.seek(0, 2)
- rlen = fp.tell()
- return file, finfo, dlen, rlen
-
- def openrsrc(name, *mode):
- if not mode:
- mode = '*rb'
- else:
- mode = '*' + mode[0]
- return openrf(name, mode)
-
- else:
- #
- # Glue code for non-macintosh useage
- #
-
- 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 = string.replace(file, ':', '-', 1)
- 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 = ''
- self.hqxdata = ''
- self.linelen = LINELEN-1
-
- def write(self, data):
- self.data = self.data + data
- datalen = len(self.data)
- todo = (datalen/3)*3
- data = self.data[:todo]
- self.data = self.data[todo:]
- if not data:
- return
- self.hqxdata = self.hqxdata + binascii.b2a_hqx(data)
- self._flush(0)
-
- def _flush(self, force):
- first = 0
- while first <= len(self.hqxdata)-self.linelen:
- last = first + self.linelen
- self.ofp.write(self.hqxdata[first:last]+'\n')
- self.linelen = LINELEN
- first = last
- self.hqxdata = self.hqxdata[first:]
- if force:
- self.ofp.write(self.hqxdata + ':\n')
-
- def close(self):
- if self.data:
- self.hqxdata = \
- self.hqxdata + binascii.b2a_hqx(self.data)
- self._flush(1)
- self.ofp.close()
- del self.ofp
-
- 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):
- 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()
- del self.ofp
-
- 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 must be converted 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):
- name = name
- nl = len(name)
- if nl > 63:
- raise Error, 'Filename too long'
- d = chr(nl) + name + '\0'
- d2 = finfo.Type + finfo.Creator
-
- # Force all structs to be packed with big-endian
- 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):
- # XXXX Should this be here??
- # self.crc = binascii.crc_hqx('\0\0', self.crc)
- 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
- del self.ofp
-
- 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
- while 1:
- d = ifp.read(128000)
- if not d: break
- ofp.write(d)
- ofp.close_data()
- ifp.close()
-
- ifp = openrsrc(inp, 'rb')
- while 1:
- d = ifp.read(128000)
- if not d: break
- 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, totalwtd):
- """Read at least wtd bytes (or until EOF)"""
- decdata = ''
- wtd = totalwtd
- #
- # 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)
- 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 = totalwtd - 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:]
- return rv
-
- def _fill(self, wtd):
- self.pre_buffer = self.pre_buffer + self.ifp.read(wtd+4)
- if self.ifp.eof:
- self.post_buffer = self.post_buffer + \
- binascii.rledecode_hqx(self.pre_buffer)
- self.pre_buffer = ''
- return
-
- #
- # Obfuscated code ahead. We have to take care that we don't
- # end up with an orphaned RUNCHAR later on. So, we keep a couple
- # of bytes in the buffer, depending on what the end of
- # the buffer looks like:
- # '\220\0\220' - Keep 3 bytes: repeated \220 (escaped as \220\0)
- # '?\220' - Keep 2 bytes: repeated something-else
- # '\220\0' - Escaped \220: Keep 2 bytes.
- # '?\220?' - Complete repeat sequence: decode all
- # otherwise: keep 1 byte.
- #
- mark = len(self.pre_buffer)
- if self.pre_buffer[-3:] == RUNCHAR + '\0' + RUNCHAR:
- mark = mark - 3
- elif self.pre_buffer[-1] == RUNCHAR:
- mark = mark - 2
- elif self.pre_buffer[-2:] == RUNCHAR + '\0':
- mark = mark - 2
- elif self.pre_buffer[-2] == RUNCHAR:
- pass # Decode all
- else:
- mark = mark - 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"
- # Cater for \r\n terminated lines (which show up as \n\r, hence
- # all lines start with \r)
- if ch == '\r':
- continue
- if ch == ':':
- break
- if ch != '\n':
- dummy = ifp.readline()
-
- 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 = binascii.crc_hqx('\0\0', self.crc)
- # XXXX Is this needed??
- self.crc = self.crc & 0xffff
- 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]
-
- 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
- rv = ''
- while len(rv) < n:
- rv = rv + self._read(n-len(rv))
- self.dlen = self.dlen - n
- return rv
-
- 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
- while 1:
- d = ifp.read(128000)
- if not d: break
- ofp.write(d)
- ofp.close()
- ifp.close_data()
-
- d = ifp.read_rsrc(128000)
- if d:
- ofp = openrsrc(out, 'wb')
- ofp.write(d)
- while 1:
- d = ifp.read_rsrc(128000)
- if not d: break
- 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.PromptGetFile('File to convert:')
- 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()
-