]> git.ipfire.org Git - thirdparty/Python/cpython.git/commitdiff
Implement binhex protocol.
authorJack Jansen <jack.jansen@cwi.nl>
Mon, 7 Aug 1995 14:36:51 +0000 (14:36 +0000)
committerJack Jansen <jack.jansen@cwi.nl>
Mon, 7 Aug 1995 14:36:51 +0000 (14:36 +0000)
Note: binhex works, hexbin does not work yet.

Lib/binhex.py [new file with mode: 0644]

diff --git a/Lib/binhex.py b/Lib/binhex.py
new file mode 100644 (file)
index 0000000..ac7dcfc
--- /dev/null
@@ -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()
+