[Python-checkins] python/dist/src/Tools/unicode gencodec.py, NONE, 1.1

Fri Oct 21 15:45:21 CEST 2005

Update of /cvsroot/python/python/dist/src/Tools/unicode
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv13659/Tools/unicode
Added Files:
	gencodec.py 
Log Message:
Moved gencodec.py to the Tools/unicode/ directory.
Added new support for decoding tables.
Cleaned up the implementation a bit.
--- NEW FILE: gencodec.py ---
""" Unicode Mapping Parser and Codec Generator.
This script parses Unicode mapping files as available from the Unicode
site (ftp://ftp.unicode.org/Public/MAPPINGS/) and creates Python codec
modules from them. The codecs use the standard character mapping codec
to actually apply the mapping.
Synopsis: gencodec.py dir codec_prefix
All files in dir are scanned and those producing non-empty mappings
will be written to <codec_prefix><mapname>.py with <mapname> being the
first part of the map's filename ('a' in a.b.c.txt) converted to
lowercase with hyphens replaced by underscores.
The tool also writes marshalled versions of the mapping tables to the
same location (with .mapping extension).
Written by Marc-Andre Lemburg (mal at lemburg.com). Modified to generate
Unicode table maps for decoding.
(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
(c) Copyright Guido van Rossum, 2000.
(c) Copyright Marc-Andre Lemburg, 2005.
"""#"
import re, os, time, marshal, codecs
# Maximum allowed size of charmap tables
MAX_TABLE_SIZE = 8192
# Standard undefined Unicode code point
UNI_UNDEFINED = unichr(0xFFFE)
mapRE = re.compile('((?:0x[0-9a-fA-F]+\+?)+)'
 '\s+'
 '((?:(?:0x[0-9a-fA-Z]+|<[A-Za-z]+>)\+?)*)'
 '\s*'
 '(#.+)?')
def parsecodes(codes,
 len=len, filter=filter,range=range):
 """ Converts code combinations to either a single code integer
 or a tuple of integers.
 meta-codes (in angular brackets, e.g. <LR> and <RL>) are
 ignored.
 Empty codes or illegal ones are returned as None.
 """
 if not codes:
 return None
 l = codes.split('+')
 if len(l) == 1:
 return int(l[0],16)
 for i in range(len(l)):
 try:
 l[i] = int(l[i],16)
 except ValueError:
 l[i] = None
 l = filter(lambda x: x is not None, l)
 if len(l) == 1:
 return l[0]
 else:
 return tuple(l)
def readmap(filename):
 f = open(filename,'r')
 lines = f.readlines()
 f.close()
 enc2uni = {}
 identity = []
 unmapped = range(256)
 # UTC mapping tables per convention don't include the identity
 # mappings for code points 0x00 - 0x1F and 0x7F, unless these are
 # explicitly mapped to different characters or undefined
 for i in range(32) + [127]:
 identity.append(i)
 unmapped.remove(i)
 enc2uni[i] = (i, 'CONTROL CHARACTER')
 for line in lines:
 line = line.strip()
 if not line or line[0] == '#':
 continue
 m = mapRE.match(line)
 if not m:
 #print '* not matched: %s' % repr(line)
 continue
 enc,uni,comment = m.groups()
 enc = parsecodes(enc)
 uni = parsecodes(uni)
 if comment is None:
 comment = ''
 else:
 comment = comment[1:].strip()
 if enc < 256:
 if enc in unmapped:
 unmapped.remove(enc)
 if enc == uni:
 identity.append(enc)
 enc2uni[enc] = (uni,comment)
 else:
 enc2uni[enc] = (uni,comment)
 # If there are more identity-mapped entries than unmapped entries,
 # it pays to generate an identity dictionary first, and add explicit
 # mappings to None for the rest
 if len(identity) >= len(unmapped):
 for enc in unmapped:
 enc2uni[enc] = (None, "")
 enc2uni['IDENTITY'] = 256
 return enc2uni
def hexrepr(t):
 if t is None:
 return 'None'
 try:
 len(t)
 except:
 return '0x%04x' % t
 try:
 return '(' + ', '.join(map(lambda t: '0x%04x' % t, t)) + ')'
 except TypeError, why:
 print '* failed to convert %r: %s' % (t, why)
 raise
def python_mapdef_code(varname, map, comments=1):
 l = []
 append = l.append
 if map.has_key("IDENTITY"):
 append("%s = codecs.make_identity_dict(range(%d))" %
 (varname, map["IDENTITY"]))
 append("%s.update({" % varname)
 splits = 1
 del map["IDENTITY"]
 identity = 1
 else:
 append("%s = {" % varname)
 splits = 0
 identity = 0
 mappings = map.items()
 mappings.sort()
 i = 0
 for mapkey, mapvalue in mappings:
 mapcomment = ''
 if isinstance(mapkey, tuple):
 (mapkey, mapcomment) = mapkey
 if isinstance(mapvalue, tuple):
 (mapvalue, mapcomment) = mapvalue
 if mapkey is None:
 continue
 if (identity and
 mapkey == mapvalue and
 mapkey < 256):
 # No need to include identity mappings, since these
 # are already set for the first 256 code points.
 continue
 key = hexrepr(mapkey)
 value = hexrepr(mapvalue)
 if mapcomment and comments:
 append(' %s: %s,\t# %s' % (key, value, mapcomment))
 else:
 append(' %s: %s,' % (key, value))
 i += 1
 if i == 4096:
 # Split the definition into parts to that the Python
 # parser doesn't dump core
 if splits == 0:
 append('}')
 else:
 append('})')
 append('%s.update({' % varname)
 i = 0
 splits = splits + 1
 if splits == 0:
 append('}')
 else:
 append('})')
 return l
def python_tabledef_code(varname, map, comments=1):
 l = []
 append = l.append
 append('%s = (' % varname)
 # Analyze map and create table dict
 mappings = map.items()
 mappings.sort()
 table = {}
 maxkey = 0
 if map.has_key('IDENTITY'):
 for key in range(256):
 table[key] = (key, '')
 maxkey = 255
 del map['IDENTITY']
 for mapkey, mapvalue in mappings:
 mapcomment = ''
 if isinstance(mapkey, tuple):
 (mapkey, mapcomment) = mapkey
 if isinstance(mapvalue, tuple):
 (mapvalue, mapcomment) = mapvalue
 if mapkey is None:
 continue
 table[mapkey] = (mapvalue, mapcomment)
 if mapkey > maxkey:
 maxkey = mapkey
 if maxkey > MAX_TABLE_SIZE:
 # Table too large
 return None
 # Create table code
 for key in range(maxkey + 1):
 if key not in table:
 mapvalue = None
 mapcomment = 'UNDEFINED'
 else:
 mapvalue, mapcomment = table[key]
 if mapvalue is None:
 mapchar = UNI_UNDEFINED
 else:
 if isinstance(mapvalue, tuple):
 # 1-n mappings not supported
 return None
 else:
 mapchar = unichr(mapvalue)
 if mapcomment and comments:
 append(' %r\t# %s -> %s' % (mapchar,
 hexrepr(key),
 mapcomment))
 else:
 append(' %r' % mapchar)
 append(')')
 return l
def codegen(name, map, comments=1):
 """ Returns Python source for the given map.
 Comments are included in the source, if comments is true (default).
 """
 # Generate code
 decoding_map_code = python_mapdef_code(
 'decoding_map',
 map,
 comments=comments)
 decoding_table_code = python_tabledef_code(
 'decoding_table',
 map,
 comments=comments)
 encoding_map_code = python_mapdef_code(
 'encoding_map',
 codecs.make_encoding_map(map),
 comments=comments)
 l = [
 '''\
""" Python Character Mapping Codec generated from '%s' with gencodec.py.
"""#"
import codecs
### Codec APIs
class Codec(codecs.Codec):
 def encode(self,input,errors='strict'):
 return codecs.charmap_encode(input,errors,encoding_map)
 def decode(self,input,errors='strict'):
''' % name
 ]
 if decoding_table_code:
 l.append('''\
 return codecs.charmap_decode(input,errors,decoding_table)''')
 else:
 l.append('''\
 return codecs.charmap_decode(input,errors,decoding_map)''')
 
 l.append(''' 
class StreamWriter(Codec,codecs.StreamWriter):
 pass
class StreamReader(Codec,codecs.StreamReader):
 pass
### encodings module API
def getregentry():
 return (Codec().encode,Codec().decode,StreamReader,StreamWriter)
### Decoding Map
''')
 l.extend(decoding_map_code)
 # Add optional decoding table
 if decoding_table_code:
 l.append('''
### Decoding Table
''')
 l.extend(decoding_table_code)
 l.append('''
### Encoding Map
''')
 l.extend(encoding_map_code)
 
 return '\n'.join(l)
def pymap(name,map,pyfile,comments=1):
 code = codegen(name,map,comments)
 f = open(pyfile,'w')
 f.write(code)
 f.close()
def marshalmap(name,map,marshalfile):
 d = {}
 for e,(u,c) in map.items():
 d[e] = (u,c)
 f = open(marshalfile,'wb')
 marshal.dump(d,f)
 f.close()
def convertdir(dir,prefix='',comments=1):
 mapnames = os.listdir(dir)
 for mapname in mapnames:
 mappathname = os.path.join(dir, mapname)
 name = os.path.split(mapname)[1]
 name = name.replace('-','_')
 name = name.split('.')[0]
 name = name.lower()
 codefile = name + '.py'
 marshalfile = name + '.mapping'
 print 'converting %s to %s and %s' % (mapname,
 prefix + codefile,
 prefix + marshalfile)
 try:
 map = readmap(os.path.join(dir,mapname))
 if not map:
 print '* map is empty; skipping'
 else:
 pymap(mappathname, map, prefix + codefile,comments)
 marshalmap(mappathname, map, prefix + marshalfile)
 except ValueError, why:
 print '* conversion failed: %s' % why
 raise
def rewritepythondir(dir,prefix='',comments=1):
 mapnames = os.listdir(dir)
 for mapname in mapnames:
 if not mapname.endswith('.mapping'):
 continue
 codefile = mapname[:-len('.mapping')] + '.py'
 print 'converting %s to %s' % (mapname,
 prefix + codefile)
 try:
 map = marshal.load(open(os.path.join(dir,mapname),
 'rb'))
 if not map:
 print '* map is empty; skipping'
 else:
 pymap(mapname, map, prefix + codefile,comments)
 except ValueError, why:
 print '* conversion failed: %s' % why
if __name__ == '__main__':
 import sys
 if 1:
 apply(convertdir,tuple(sys.argv[1:]))
 else:
 apply(rewritepythondir,tuple(sys.argv[1:]))